{
 "name": "CombiCert boiler fault codes",
 "publisher": "CombiCert Ltd, Telford, Shropshire (Gas Safe 621146)",
 "url": "https://combicert.co.uk/boiler-fault-codes/",
 "dateModified": "2026-11-01",
 "count": 259,
 "note": "Explanations written by CombiCert from the cited manufacturer manuals. General information, not a diagnosis. If you smell gas call 0800 111 999. Only a Gas Safe registered engineer may work inside a gas boiler.",
 "fields": [
  "id",
  "code",
  "brand",
  "model_range",
  "category",
  "meaning",
  "homeowner_action",
  "when_to_call_engineer",
  "engineer_after_one_reset",
  "page_url",
  "source_manual",
  "source_doc",
  "source_pages",
  "source_url",
  "source_type"
 ],
 "codes": [
  {
   "id": "worcester-fa306",
   "code": "FA 306",
   "brand": "Worcester Bosch",
   "model_range": "Greenstar i ErP (Greenstar 25i / 30i combi)",
   "category": "Ignition / flame",
   "meaning": "A flame (ionisation) signal was detected after the gas valve closed.",
   "homeowner_action": "There is no homeowner check that fixes this code. Write down the full code, press reset once, and if it comes back leave the boiler off.",
   "when_to_call_engineer": "Call a Gas Safe registered engineer if the code comes back after one reset. Ignition and flame faults involve gas, so this is engineer-only.",
   "engineer_after_one_reset": true,
   "page_url": "https://combicert.co.uk/boiler-fault-codes/worcester-bosch/#worcester-fa306",
   "source_manual": "Greenstar i ErP Installation, Commissioning and Servicing Instructions",
   "source_doc": "6 720 806 944 (2016/07)",
   "source_pages": "pp. 65–68, section 8.1.2 Error codes (Table 48)",
   "source_url": "https://www.worcester-bosch.co.uk/support/literature/download/6720806944",
   "source_type": "manufacturer"
  },
  {
   "id": "worcester-ea227",
   "code": "EA 227",
   "brand": "Worcester Bosch",
   "model_range": "Greenstar i ErP (Greenstar 25i / 30i combi)",
   "category": "Ignition / flame",
   "meaning": "No flame was detected after ignition, so the boiler locked out.",
   "homeowner_action": "Check another gas appliance such as the hob works, the gas meter valve is on and, on a prepayment meter, there is credit. In freezing weather, check the plastic condensate pipe outside: if it is frozen, pour warm (not boiling) water along it. Then press reset once. If the code comes back, stop resetting.",
   "when_to_call_engineer": "Call a Gas Safe registered engineer if the gas supply is fine and the code returns after one reset. Ignition and flame faults involve gas, so this is engineer-only.",
   "engineer_after_one_reset": false,
   "page_url": "https://combicert.co.uk/boiler-fault-codes/worcester-bosch/#worcester-ea227",
   "source_manual": "Greenstar i ErP Installation, Commissioning and Servicing Instructions",
   "source_doc": "6 720 806 944 (2016/07)",
   "source_pages": "pp. 65–68, section 8.1.2 Error codes (Table 48)",
   "source_url": "https://www.worcester-bosch.co.uk/support/literature/download/6720806944",
   "source_type": "manufacturer"
  },
  {
   "id": "worcester-f7228",
   "code": "F7 228",
   "brand": "Worcester Bosch",
   "model_range": "Greenstar i ErP (Greenstar 25i / 30i combi)",
   "category": "Ignition / flame",
   "meaning": "A flame signal was detected before the burner started.",
   "homeowner_action": "There is no homeowner check that fixes this code. Write down the full code, press reset once, and if it comes back leave the boiler off.",
   "when_to_call_engineer": "Call a Gas Safe registered engineer if the code comes back after one reset. Ignition and flame faults involve gas, so this is engineer-only.",
   "engineer_after_one_reset": true,
   "page_url": "https://combicert.co.uk/boiler-fault-codes/worcester-bosch/#worcester-f7228",
   "source_manual": "Greenstar i ErP Installation, Commissioning and Servicing Instructions",
   "source_doc": "6 720 806 944 (2016/07)",
   "source_pages": "pp. 65–68, section 8.1.2 Error codes (Table 48)",
   "source_url": "https://www.worcester-bosch.co.uk/support/literature/download/6720806944",
   "source_type": "manufacturer"
  },
  {
   "id": "worcester-ea229",
   "code": "EA 229",
   "brand": "Worcester Bosch",
   "model_range": "Greenstar i ErP (Greenstar 25i / 30i combi)",
   "category": "Ignition / flame",
   "meaning": "The flame signal was lost while the boiler was running.",
   "homeowner_action": "There is no homeowner check that fixes this code. Write down the full code, press reset once, and if it comes back leave the boiler off.",
   "when_to_call_engineer": "Call a Gas Safe registered engineer if the code comes back after one reset. Ignition and flame faults involve gas, so this is engineer-only.",
   "engineer_after_one_reset": true,
   "page_url": "https://combicert.co.uk/boiler-fault-codes/worcester-bosch/#worcester-ea229",
   "source_manual": "Greenstar i ErP Installation, Commissioning and Servicing Instructions",
   "source_doc": "6 720 806 944 (2016/07)",
   "source_pages": "pp. 65–68, section 8.1.2 Error codes (Table 48)",
   "source_url": "https://www.worcester-bosch.co.uk/support/literature/download/6720806944",
   "source_type": "manufacturer"
  },
  {
   "id": "worcester-f0238",
   "code": "F0 238",
   "brand": "Worcester Bosch",
   "model_range": "Greenstar i ErP (Greenstar 25i / 30i combi)",
   "category": "Ignition / flame",
   "meaning": "Gas valve or control box error.",
   "homeowner_action": "There is no homeowner check that fixes this code. Write down the full code, press reset once, and if it comes back leave the boiler off.",
   "when_to_call_engineer": "Call a Gas Safe registered engineer if the code comes back after one reset. Ignition and flame faults involve gas, so this is engineer-only.",
   "engineer_after_one_reset": true,
   "page_url": "https://combicert.co.uk/boiler-fault-codes/worcester-bosch/#worcester-f0238",
   "source_manual": "Greenstar i ErP Installation, Commissioning and Servicing Instructions",
   "source_doc": "6 720 806 944 (2016/07)",
   "source_pages": "pp. 65–68, section 8.1.2 Error codes (Table 48)",
   "source_url": "https://www.worcester-bosch.co.uk/support/literature/download/6720806944",
   "source_type": "manufacturer"
  },
  {
   "id": "worcester-a1281",
   "code": "A1 281",
   "brand": "Worcester Bosch",
   "model_range": "Greenstar i ErP (Greenstar 25i / 30i combi)",
   "category": "Water pressure / circulation",
   "meaning": "The pump appears to be stuck or running dry.",
   "homeowner_action": "There is no homeowner check that fixes this code. Write down the full code, press reset once, and if it comes back leave the boiler off.",
   "when_to_call_engineer": "Call a Gas Safe registered engineer if you have to top up more than once every few months, the gauge goes above about 2.5 bar when hot, water drips from the outside overflow pipe, or the code returns after topping up.",
   "engineer_after_one_reset": true,
   "page_url": "https://combicert.co.uk/boiler-fault-codes/worcester-bosch/#worcester-a1281",
   "source_manual": "Greenstar i ErP Installation, Commissioning and Servicing Instructions",
   "source_doc": "6 720 806 944 (2016/07)",
   "source_pages": "pp. 65–68, section 8.1.2 Error codes (Table 48)",
   "source_url": "https://www.worcester-bosch.co.uk/support/literature/download/6720806944",
   "source_type": "manufacturer"
  },
  {
   "id": "worcester-e9276",
   "code": "E9 276",
   "brand": "Worcester Bosch",
   "model_range": "Greenstar i ErP (Greenstar 25i / 30i combi)",
   "category": "Temperature / overheat",
   "meaning": "The primary flow temperature went above 95 °C.",
   "homeowner_action": "Let the boiler cool for 20 to 30 minutes, then press reset once. If the code comes back, leave the boiler off.",
   "when_to_call_engineer": "Call a Gas Safe registered engineer if the code comes back after one reset. Overheat shut-downs are safety devices doing their job, so this is engineer-only.",
   "engineer_after_one_reset": true,
   "page_url": "https://combicert.co.uk/boiler-fault-codes/worcester-bosch/#worcester-e9276",
   "source_manual": "Greenstar i ErP Installation, Commissioning and Servicing Instructions",
   "source_doc": "6 720 806 944 (2016/07)",
   "source_pages": "pp. 65–68, section 8.1.2 Error codes (Table 48)",
   "source_url": "https://www.worcester-bosch.co.uk/support/literature/download/6720806944",
   "source_type": "manufacturer"
  },
  {
   "id": "worcester-e9224",
   "code": "E9 224",
   "brand": "Worcester Bosch",
   "model_range": "Greenstar i ErP (Greenstar 25i / 30i combi)",
   "category": "Temperature / overheat",
   "meaning": "The flue thermostat or the high-limit (overheat) thermostat has opened.",
   "homeowner_action": "Let the boiler cool for 20 to 30 minutes, then press reset once. If the code comes back, leave the boiler off.",
   "when_to_call_engineer": "Call a Gas Safe registered engineer if the code comes back after one reset. Overheat shut-downs are safety devices doing their job, so this is engineer-only.",
   "engineer_after_one_reset": true,
   "page_url": "https://combicert.co.uk/boiler-fault-codes/worcester-bosch/#worcester-e9224",
   "source_manual": "Greenstar i ErP Installation, Commissioning and Servicing Instructions",
   "source_doc": "6 720 806 944 (2016/07)",
   "source_pages": "pp. 65–68, section 8.1.2 Error codes (Table 48)",
   "source_url": "https://www.worcester-bosch.co.uk/support/literature/download/6720806944",
   "source_type": "manufacturer"
  },
  {
   "id": "worcester-d4341",
   "code": "D4 341",
   "brand": "Worcester Bosch",
   "model_range": "Greenstar i ErP (Greenstar 25i / 30i combi)",
   "category": "Temperature / overheat",
   "meaning": "The primary flow temperature is rising too quickly.",
   "homeowner_action": "Let the boiler cool for 20 to 30 minutes, then press reset once. If the code comes back, leave the boiler off.",
   "when_to_call_engineer": "Call a Gas Safe registered engineer if the code comes back after one reset. Overheat shut-downs are safety devices doing their job, so this is engineer-only.",
   "engineer_after_one_reset": true,
   "page_url": "https://combicert.co.uk/boiler-fault-codes/worcester-bosch/#worcester-d4341",
   "source_manual": "Greenstar i ErP Installation, Commissioning and Servicing Instructions",
   "source_doc": "6 720 806 944 (2016/07)",
   "source_pages": "pp. 65–68, section 8.1.2 Error codes (Table 48)",
   "source_url": "https://www.worcester-bosch.co.uk/support/literature/download/6720806944",
   "source_type": "manufacturer"
  },
  {
   "id": "worcester-c7214",
   "code": "C7 214",
   "brand": "Worcester Bosch",
   "model_range": "Greenstar i ErP (Greenstar 25i / 30i combi)",
   "category": "Flue / fan / air",
   "meaning": "The fan did not run during start-up.",
   "homeowner_action": "There is no homeowner check that fixes this code. Write down the full code, press reset once, and if it comes back leave the boiler off.",
   "when_to_call_engineer": "Call a Gas Safe registered engineer if the terminal looks clear and the code returns. Flue and fan faults can affect how combustion gases leave your home, so this is engineer-only.",
   "engineer_after_one_reset": true,
   "page_url": "https://combicert.co.uk/boiler-fault-codes/worcester-bosch/#worcester-c7214",
   "source_manual": "Greenstar i ErP Installation, Commissioning and Servicing Instructions",
   "source_doc": "6 720 806 944 (2016/07)",
   "source_pages": "pp. 65–68, section 8.1.2 Error codes (Table 48)",
   "source_url": "https://www.worcester-bosch.co.uk/support/literature/download/6720806944",
   "source_type": "manufacturer"
  },
  {
   "id": "worcester-c6215",
   "code": "C6 215",
   "brand": "Worcester Bosch",
   "model_range": "Greenstar i ErP (Greenstar 25i / 30i combi)",
   "category": "Flue / fan / air",
   "meaning": "The fan is running too fast.",
   "homeowner_action": "There is no homeowner check that fixes this code. Write down the full code, press reset once, and if it comes back leave the boiler off.",
   "when_to_call_engineer": "Call a Gas Safe registered engineer if the terminal looks clear and the code returns. Flue and fan faults can affect how combustion gases leave your home, so this is engineer-only.",
   "engineer_after_one_reset": true,
   "page_url": "https://combicert.co.uk/boiler-fault-codes/worcester-bosch/#worcester-c6215",
   "source_manual": "Greenstar i ErP Installation, Commissioning and Servicing Instructions",
   "source_doc": "6 720 806 944 (2016/07)",
   "source_pages": "pp. 65–68, section 8.1.2 Error codes (Table 48)",
   "source_url": "https://www.worcester-bosch.co.uk/support/literature/download/6720806944",
   "source_type": "manufacturer"
  },
  {
   "id": "worcester-c6216",
   "code": "C6 216",
   "brand": "Worcester Bosch",
   "model_range": "Greenstar i ErP (Greenstar 25i / 30i combi)",
   "category": "Flue / fan / air",
   "meaning": "The fan is running too slowly.",
   "homeowner_action": "There is no homeowner check that fixes this code. Write down the full code, press reset once, and if it comes back leave the boiler off.",
   "when_to_call_engineer": "Call a Gas Safe registered engineer if the terminal looks clear and the code returns. Flue and fan faults can affect how combustion gases leave your home, so this is engineer-only.",
   "engineer_after_one_reset": true,
   "page_url": "https://combicert.co.uk/boiler-fault-codes/worcester-bosch/#worcester-c6216",
   "source_manual": "Greenstar i ErP Installation, Commissioning and Servicing Instructions",
   "source_doc": "6 720 806 944 (2016/07)",
   "source_pages": "pp. 65–68, section 8.1.2 Error codes (Table 48)",
   "source_url": "https://www.worcester-bosch.co.uk/support/literature/download/6720806944",
   "source_type": "manufacturer"
  },
  {
   "id": "worcester-c7217",
   "code": "C7 217",
   "brand": "Worcester Bosch",
   "model_range": "Greenstar i ErP (Greenstar 25i / 30i combi)",
   "category": "Flue / fan / air",
   "meaning": "The fan stopped while the boiler was running.",
   "homeowner_action": "There is no homeowner check that fixes this code. Write down the full code, press reset once, and if it comes back leave the boiler off.",
   "when_to_call_engineer": "Call a Gas Safe registered engineer if the terminal looks clear and the code returns. Flue and fan faults can affect how combustion gases leave your home, so this is engineer-only.",
   "engineer_after_one_reset": true,
   "page_url": "https://combicert.co.uk/boiler-fault-codes/worcester-bosch/#worcester-c7217",
   "source_manual": "Greenstar i ErP Installation, Commissioning and Servicing Instructions",
   "source_doc": "6 720 806 944 (2016/07)",
   "source_pages": "pp. 65–68, section 8.1.2 Error codes (Table 48)",
   "source_url": "https://www.worcester-bosch.co.uk/support/literature/download/6720806944",
   "source_type": "manufacturer"
  },
  {
   "id": "worcester-c1264",
   "code": "C1 264",
   "brand": "Worcester Bosch",
   "model_range": "Greenstar i ErP (Greenstar 25i / 30i combi)",
   "category": "Flue / fan / air",
   "meaning": "The fan stopped during operation.",
   "homeowner_action": "There is no homeowner check that fixes this code. Write down the full code, press reset once, and if it comes back leave the boiler off.",
   "when_to_call_engineer": "Call a Gas Safe registered engineer if the terminal looks clear and the code returns. Flue and fan faults can affect how combustion gases leave your home, so this is engineer-only.",
   "engineer_after_one_reset": true,
   "page_url": "https://combicert.co.uk/boiler-fault-codes/worcester-bosch/#worcester-c1264",
   "source_manual": "Greenstar i ErP Installation, Commissioning and Servicing Instructions",
   "source_doc": "6 720 806 944 (2016/07)",
   "source_pages": "pp. 65–68, section 8.1.2 Error codes (Table 48)",
   "source_url": "https://www.worcester-bosch.co.uk/support/literature/download/6720806944",
   "source_type": "manufacturer"
  },
  {
   "id": "worcester-e2222",
   "code": "E2 222",
   "brand": "Worcester Bosch",
   "model_range": "Greenstar i ErP (Greenstar 25i / 30i combi)",
   "category": "Sensors / thermistors",
   "meaning": "The flow temperature sensor reads as a short circuit.",
   "homeowner_action": "Write down the full code. Check the boiler has power, then switch it off and on at its mains switch or press reset once. If the code comes back, leave it there: sensors are inside the casing.",
   "when_to_call_engineer": "Call a Gas Safe registered engineer if the code returns. Testing and replacing sensors means opening the casing, so this is engineer-only.",
   "engineer_after_one_reset": true,
   "page_url": "https://combicert.co.uk/boiler-fault-codes/worcester-bosch/#worcester-e2222",
   "source_manual": "Greenstar i ErP Installation, Commissioning and Servicing Instructions",
   "source_doc": "6 720 806 944 (2016/07)",
   "source_pages": "pp. 65–68, section 8.1.2 Error codes (Table 48)",
   "source_url": "https://www.worcester-bosch.co.uk/support/literature/download/6720806944",
   "source_type": "manufacturer"
  },
  {
   "id": "worcester-e2223",
   "code": "E2 223",
   "brand": "Worcester Bosch",
   "model_range": "Greenstar i ErP (Greenstar 25i / 30i combi)",
   "category": "Sensors / thermistors",
   "meaning": "The flow temperature sensor is disconnected.",
   "homeowner_action": "Write down the full code. Check the boiler has power, then switch it off and on at its mains switch or press reset once. If the code comes back, leave it there: sensors are inside the casing.",
   "when_to_call_engineer": "Call a Gas Safe registered engineer if the code returns. Testing and replacing sensors means opening the casing, so this is engineer-only.",
   "engineer_after_one_reset": true,
   "page_url": "https://combicert.co.uk/boiler-fault-codes/worcester-bosch/#worcester-e2223",
   "source_manual": "Greenstar i ErP Installation, Commissioning and Servicing Instructions",
   "source_doc": "6 720 806 944 (2016/07)",
   "source_pages": "pp. 65–68, section 8.1.2 Error codes (Table 48)",
   "source_url": "https://www.worcester-bosch.co.uk/support/literature/download/6720806944",
   "source_type": "manufacturer"
  },
  {
   "id": "worcester-e2350",
   "code": "E2 350",
   "brand": "Worcester Bosch",
   "model_range": "Greenstar i ErP (Greenstar 25i / 30i combi)",
   "category": "Sensors / thermistors",
   "meaning": "Flow temperature sensor short circuit (second sensor code).",
   "homeowner_action": "Write down the full code. Check the boiler has power, then switch it off and on at its mains switch or press reset once. If the code comes back, leave it there: sensors are inside the casing.",
   "when_to_call_engineer": "Call a Gas Safe registered engineer if the code returns. Testing and replacing sensors means opening the casing, so this is engineer-only.",
   "engineer_after_one_reset": true,
   "page_url": "https://combicert.co.uk/boiler-fault-codes/worcester-bosch/#worcester-e2350",
   "source_manual": "Greenstar i ErP Installation, Commissioning and Servicing Instructions",
   "source_doc": "6 720 806 944 (2016/07)",
   "source_pages": "pp. 65–68, section 8.1.2 Error codes (Table 48)",
   "source_url": "https://www.worcester-bosch.co.uk/support/literature/download/6720806944",
   "source_type": "manufacturer"
  },
  {
   "id": "worcester-e2351",
   "code": "E2 351",
   "brand": "Worcester Bosch",
   "model_range": "Greenstar i ErP (Greenstar 25i / 30i combi)",
   "category": "Sensors / thermistors",
   "meaning": "Flow temperature sensor disconnected (second sensor code).",
   "homeowner_action": "Write down the full code. Check the boiler has power, then switch it off and on at its mains switch or press reset once. If the code comes back, leave it there: sensors are inside the casing.",
   "when_to_call_engineer": "Call a Gas Safe registered engineer if the code returns. Testing and replacing sensors means opening the casing, so this is engineer-only.",
   "engineer_after_one_reset": true,
   "page_url": "https://combicert.co.uk/boiler-fault-codes/worcester-bosch/#worcester-e2351",
   "source_manual": "Greenstar i ErP Installation, Commissioning and Servicing Instructions",
   "source_doc": "6 720 806 944 (2016/07)",
   "source_pages": "pp. 65–68, section 8.1.2 Error codes (Table 48)",
   "source_url": "https://www.worcester-bosch.co.uk/support/literature/download/6720806944",
   "source_type": "manufacturer"
  },
  {
   "id": "worcester-cc800",
   "code": "CC 800",
   "brand": "Worcester Bosch",
   "model_range": "Greenstar i ErP (Greenstar 25i / 30i combi)",
   "category": "Sensors / thermistors",
   "meaning": "Outdoor weather sensor fault (only shown when an outdoor sensor accessory is connected).",
   "homeowner_action": "Nothing urgent: the boiler normally keeps heating without the outdoor sensor, using a fixed setting. Press reset once to see if it clears.",
   "when_to_call_engineer": "Call a Gas Safe registered engineer if the code returns. Testing and replacing sensors means opening the casing, so this is engineer-only.",
   "engineer_after_one_reset": true,
   "page_url": "https://combicert.co.uk/boiler-fault-codes/worcester-bosch/#worcester-cc800",
   "source_manual": "Greenstar i ErP Installation, Commissioning and Servicing Instructions",
   "source_doc": "6 720 806 944 (2016/07)",
   "source_pages": "pp. 65–68, section 8.1.2 Error codes (Table 48)",
   "source_url": "https://www.worcester-bosch.co.uk/support/literature/download/6720806944",
   "source_type": "manufacturer"
  },
  {
   "id": "worcester-a7808",
   "code": "A7 808",
   "brand": "Worcester Bosch",
   "model_range": "Greenstar i ErP (Greenstar 25i / 30i combi)",
   "category": "Sensors / thermistors",
   "meaning": "Hot water temperature sensor fault.",
   "homeowner_action": "Write down the full code. Check the boiler has power, then switch it off and on at its mains switch or press reset once. If the code comes back, leave it there: sensors are inside the casing.",
   "when_to_call_engineer": "Call a Gas Safe registered engineer if the code returns. Testing and replacing sensors means opening the casing, so this is engineer-only.",
   "engineer_after_one_reset": true,
   "page_url": "https://combicert.co.uk/boiler-fault-codes/worcester-bosch/#worcester-a7808",
   "source_manual": "Greenstar i ErP Installation, Commissioning and Servicing Instructions",
   "source_doc": "6 720 806 944 (2016/07)",
   "source_pages": "pp. 65–68, section 8.1.2 Error codes (Table 48)",
   "source_url": "https://www.worcester-bosch.co.uk/support/literature/download/6720806944",
   "source_type": "manufacturer"
  },
  {
   "id": "worcester-fd231",
   "code": "Fd 231",
   "brand": "Worcester Bosch",
   "model_range": "Greenstar i ErP (Greenstar 25i / 30i combi)",
   "category": "PCB / electrical",
   "meaning": "The power was interrupted while the boiler was already locked out. The previous lockout code is the real fault.",
   "homeowner_action": "Look for the code shown before Fd and use that code's advice. If the gas is on and pressure is fine, press reset once.",
   "when_to_call_engineer": "Call a Gas Safe registered engineer if the boiler locks out again, quoting the original code.",
   "engineer_after_one_reset": false,
   "page_url": "https://combicert.co.uk/boiler-fault-codes/worcester-bosch/#worcester-fd231",
   "source_manual": "Greenstar i ErP Installation, Commissioning and Servicing Instructions",
   "source_doc": "6 720 806 944 (2016/07)",
   "source_pages": "pp. 65–68, section 8.1.2 Error codes (Table 48)",
   "source_url": "https://www.worcester-bosch.co.uk/support/literature/download/6720806944",
   "source_type": "manufacturer"
  },
  {
   "id": "worcester-ea261",
   "code": "EA 261",
   "brand": "Worcester Bosch",
   "model_range": "Greenstar i ErP (Greenstar 25i / 30i combi)",
   "category": "PCB / electrical",
   "meaning": "The boiler's code plug (HCM) may be faulty.",
   "homeowner_action": "Write down the full code. Check the boiler has power and nothing else in the house has tripped, then switch the boiler off and on at its mains switch or press reset once. If the code comes back, leave the boiler off.",
   "when_to_call_engineer": "Call a Gas Safe registered engineer if the code returns. Board, wiring and gas valve checks mean opening the casing, so this is engineer-only.",
   "engineer_after_one_reset": true,
   "page_url": "https://combicert.co.uk/boiler-fault-codes/worcester-bosch/#worcester-ea261",
   "source_manual": "Greenstar i ErP Installation, Commissioning and Servicing Instructions",
   "source_doc": "6 720 806 944 (2016/07)",
   "source_pages": "pp. 65–68, section 8.1.2 Error codes (Table 48)",
   "source_url": "https://www.worcester-bosch.co.uk/support/literature/download/6720806944",
   "source_type": "manufacturer"
  },
  {
   "id": "worcester-9u233",
   "code": "9U 233",
   "brand": "Worcester Bosch",
   "model_range": "Greenstar i ErP (Greenstar 25i / 30i combi)",
   "category": "PCB / electrical",
   "meaning": "The control box or the code plug (HCM) is faulty or loose.",
   "homeowner_action": "Write down the full code. Check the boiler has power and nothing else in the house has tripped, then switch the boiler off and on at its mains switch or press reset once. If the code comes back, leave the boiler off.",
   "when_to_call_engineer": "Call a Gas Safe registered engineer if the code returns. Board, wiring and gas valve checks mean opening the casing, so this is engineer-only.",
   "engineer_after_one_reset": true,
   "page_url": "https://combicert.co.uk/boiler-fault-codes/worcester-bosch/#worcester-9u233",
   "source_manual": "Greenstar i ErP Installation, Commissioning and Servicing Instructions",
   "source_doc": "6 720 806 944 (2016/07)",
   "source_pages": "pp. 65–68, section 8.1.2 Error codes (Table 48)",
   "source_url": "https://www.worcester-bosch.co.uk/support/literature/download/6720806944",
   "source_type": "manufacturer"
  },
  {
   "id": "worcester-c4237",
   "code": "C4 237",
   "brand": "Worcester Bosch",
   "model_range": "Greenstar i ErP (Greenstar 25i / 30i combi)",
   "category": "PCB / electrical",
   "meaning": "The control box or code plug (HCM) is faulty.",
   "homeowner_action": "Write down the full code. Check the boiler has power and nothing else in the house has tripped, then switch the boiler off and on at its mains switch or press reset once. If the code comes back, leave the boiler off.",
   "when_to_call_engineer": "Call a Gas Safe registered engineer if the code returns. Board, wiring and gas valve checks mean opening the casing, so this is engineer-only.",
   "engineer_after_one_reset": true,
   "page_url": "https://combicert.co.uk/boiler-fault-codes/worcester-bosch/#worcester-c4237",
   "source_manual": "Greenstar i ErP Installation, Commissioning and Servicing Instructions",
   "source_doc": "6 720 806 944 (2016/07)",
   "source_pages": "pp. 65–68, section 8.1.2 Error codes (Table 48)",
   "source_url": "https://www.worcester-bosch.co.uk/support/literature/download/6720806944",
   "source_type": "manufacturer"
  },
  {
   "id": "worcester-f0239",
   "code": "F0 239",
   "brand": "Worcester Bosch",
   "model_range": "Greenstar i ErP (Greenstar 25i / 30i combi)",
   "category": "PCB / electrical",
   "meaning": "The control box or code plug (HCM) is faulty.",
   "homeowner_action": "Write down the full code. Check the boiler has power and nothing else in the house has tripped, then switch the boiler off and on at its mains switch or press reset once. If the code comes back, leave the boiler off.",
   "when_to_call_engineer": "Call a Gas Safe registered engineer if the code returns. Board, wiring and gas valve checks mean opening the casing, so this is engineer-only.",
   "engineer_after_one_reset": true,
   "page_url": "https://combicert.co.uk/boiler-fault-codes/worcester-bosch/#worcester-f0239",
   "source_manual": "Greenstar i ErP Installation, Commissioning and Servicing Instructions",
   "source_doc": "6 720 806 944 (2016/07)",
   "source_pages": "pp. 65–68, section 8.1.2 Error codes (Table 48)",
   "source_url": "https://www.worcester-bosch.co.uk/support/literature/download/6720806944",
   "source_type": "manufacturer"
  },
  {
   "id": "worcester-f0242",
   "code": "F0 242",
   "brand": "Worcester Bosch",
   "model_range": "Greenstar i ErP (Greenstar 25i / 30i combi)",
   "category": "PCB / electrical",
   "meaning": "The control box or code plug (HCM) is faulty (the manual groups cause codes 242 to 256 together).",
   "homeowner_action": "Write down the full code. Check the boiler has power and nothing else in the house has tripped, then switch the boiler off and on at its mains switch or press reset once. If the code comes back, leave the boiler off.",
   "when_to_call_engineer": "Call a Gas Safe registered engineer if the code returns. Board, wiring and gas valve checks mean opening the casing, so this is engineer-only.",
   "engineer_after_one_reset": true,
   "page_url": "https://combicert.co.uk/boiler-fault-codes/worcester-bosch/#worcester-f0242",
   "source_manual": "Greenstar i ErP Installation, Commissioning and Servicing Instructions",
   "source_doc": "6 720 806 944 (2016/07)",
   "source_pages": "pp. 65–68, section 8.1.2 Error codes (Table 48)",
   "source_url": "https://www.worcester-bosch.co.uk/support/literature/download/6720806944",
   "source_type": "manufacturer"
  },
  {
   "id": "worcester-b7257",
   "code": "b7 257",
   "brand": "Worcester Bosch",
   "model_range": "Greenstar i ErP (Greenstar 25i / 30i combi)",
   "category": "PCB / electrical",
   "meaning": "The control box or code plug (HCM) is faulty.",
   "homeowner_action": "Write down the full code. Check the boiler has power and nothing else in the house has tripped, then switch the boiler off and on at its mains switch or press reset once. If the code comes back, leave the boiler off.",
   "when_to_call_engineer": "Call a Gas Safe registered engineer if the code returns. Board, wiring and gas valve checks mean opening the casing, so this is engineer-only.",
   "engineer_after_one_reset": true,
   "page_url": "https://combicert.co.uk/boiler-fault-codes/worcester-bosch/#worcester-b7257",
   "source_manual": "Greenstar i ErP Installation, Commissioning and Servicing Instructions",
   "source_doc": "6 720 806 944 (2016/07)",
   "source_pages": "pp. 65–68, section 8.1.2 Error codes (Table 48)",
   "source_url": "https://www.worcester-bosch.co.uk/support/literature/download/6720806944",
   "source_type": "manufacturer"
  },
  {
   "id": "worcester-f0258",
   "code": "F0 258",
   "brand": "Worcester Bosch",
   "model_range": "Greenstar i ErP (Greenstar 25i / 30i combi)",
   "category": "PCB / electrical",
   "meaning": "The control box or code plug (HCM) is faulty. The manual also lists this cause with display code EH.",
   "homeowner_action": "Write down the full code. Check the boiler has power and nothing else in the house has tripped, then switch the boiler off and on at its mains switch or press reset once. If the code comes back, leave the boiler off.",
   "when_to_call_engineer": "Call a Gas Safe registered engineer if the code returns. Board, wiring and gas valve checks mean opening the casing, so this is engineer-only.",
   "engineer_after_one_reset": true,
   "page_url": "https://combicert.co.uk/boiler-fault-codes/worcester-bosch/#worcester-f0258",
   "source_manual": "Greenstar i ErP Installation, Commissioning and Servicing Instructions",
   "source_doc": "6 720 806 944 (2016/07)",
   "source_pages": "pp. 65–68, section 8.1.2 Error codes (Table 48)",
   "source_url": "https://www.worcester-bosch.co.uk/support/literature/download/6720806944",
   "source_type": "manufacturer"
  },
  {
   "id": "worcester-f1259",
   "code": "F1 259",
   "brand": "Worcester Bosch",
   "model_range": "Greenstar i ErP (Greenstar 25i / 30i combi)",
   "category": "PCB / electrical",
   "meaning": "The control box or code plug (HCM) is faulty.",
   "homeowner_action": "Write down the full code. Check the boiler has power and nothing else in the house has tripped, then switch the boiler off and on at its mains switch or press reset once. If the code comes back, leave the boiler off.",
   "when_to_call_engineer": "Call a Gas Safe registered engineer if the code returns. Board, wiring and gas valve checks mean opening the casing, so this is engineer-only.",
   "engineer_after_one_reset": true,
   "page_url": "https://combicert.co.uk/boiler-fault-codes/worcester-bosch/#worcester-f1259",
   "source_manual": "Greenstar i ErP Installation, Commissioning and Servicing Instructions",
   "source_doc": "6 720 806 944 (2016/07)",
   "source_pages": "pp. 65–68, section 8.1.2 Error codes (Table 48)",
   "source_url": "https://www.worcester-bosch.co.uk/support/literature/download/6720806944",
   "source_type": "manufacturer"
  },
  {
   "id": "worcester-f0262",
   "code": "F0 262",
   "brand": "Worcester Bosch",
   "model_range": "Greenstar i ErP (Greenstar 25i / 30i combi)",
   "category": "PCB / electrical",
   "meaning": "The control box or code plug (HCM) is faulty.",
   "homeowner_action": "Write down the full code. Check the boiler has power and nothing else in the house has tripped, then switch the boiler off and on at its mains switch or press reset once. If the code comes back, leave the boiler off.",
   "when_to_call_engineer": "Call a Gas Safe registered engineer if the code returns. Board, wiring and gas valve checks mean opening the casing, so this is engineer-only.",
   "engineer_after_one_reset": true,
   "page_url": "https://combicert.co.uk/boiler-fault-codes/worcester-bosch/#worcester-f0262",
   "source_manual": "Greenstar i ErP Installation, Commissioning and Servicing Instructions",
   "source_doc": "6 720 806 944 (2016/07)",
   "source_pages": "pp. 65–68, section 8.1.2 Error codes (Table 48)",
   "source_url": "https://www.worcester-bosch.co.uk/support/literature/download/6720806944",
   "source_type": "manufacturer"
  },
  {
   "id": "worcester-f1263",
   "code": "F1 263",
   "brand": "Worcester Bosch",
   "model_range": "Greenstar i ErP (Greenstar 25i / 30i combi)",
   "category": "PCB / electrical",
   "meaning": "The control box or code plug (HCM) is faulty.",
   "homeowner_action": "Write down the full code. Check the boiler has power and nothing else in the house has tripped, then switch the boiler off and on at its mains switch or press reset once. If the code comes back, leave the boiler off.",
   "when_to_call_engineer": "Call a Gas Safe registered engineer if the code returns. Board, wiring and gas valve checks mean opening the casing, so this is engineer-only.",
   "engineer_after_one_reset": true,
   "page_url": "https://combicert.co.uk/boiler-fault-codes/worcester-bosch/#worcester-f1263",
   "source_manual": "Greenstar i ErP Installation, Commissioning and Servicing Instructions",
   "source_doc": "6 720 806 944 (2016/07)",
   "source_pages": "pp. 65–68, section 8.1.2 Error codes (Table 48)",
   "source_url": "https://www.worcester-bosch.co.uk/support/literature/download/6720806944",
   "source_type": "manufacturer"
  },
  {
   "id": "worcester-f0272",
   "code": "F0 272",
   "brand": "Worcester Bosch",
   "model_range": "Greenstar i ErP (Greenstar 25i / 30i combi)",
   "category": "PCB / electrical",
   "meaning": "The control box or code plug (HCM) is faulty.",
   "homeowner_action": "Write down the full code. Check the boiler has power and nothing else in the house has tripped, then switch the boiler off and on at its mains switch or press reset once. If the code comes back, leave the boiler off.",
   "when_to_call_engineer": "Call a Gas Safe registered engineer if the code returns. Board, wiring and gas valve checks mean opening the casing, so this is engineer-only.",
   "engineer_after_one_reset": true,
   "page_url": "https://combicert.co.uk/boiler-fault-codes/worcester-bosch/#worcester-f0272",
   "source_manual": "Greenstar i ErP Installation, Commissioning and Servicing Instructions",
   "source_doc": "6 720 806 944 (2016/07)",
   "source_pages": "pp. 65–68, section 8.1.2 Error codes (Table 48)",
   "source_url": "https://www.worcester-bosch.co.uk/support/literature/download/6720806944",
   "source_type": "manufacturer"
  },
  {
   "id": "worcester-f0280",
   "code": "F0 280",
   "brand": "Worcester Bosch",
   "model_range": "Greenstar i ErP (Greenstar 25i / 30i combi)",
   "category": "PCB / electrical",
   "meaning": "The control box is faulty.",
   "homeowner_action": "Write down the full code. Check the boiler has power and nothing else in the house has tripped, then switch the boiler off and on at its mains switch or press reset once. If the code comes back, leave the boiler off.",
   "when_to_call_engineer": "Call a Gas Safe registered engineer if the code returns. Board, wiring and gas valve checks mean opening the casing, so this is engineer-only.",
   "engineer_after_one_reset": true,
   "page_url": "https://combicert.co.uk/boiler-fault-codes/worcester-bosch/#worcester-f0280",
   "source_manual": "Greenstar i ErP Installation, Commissioning and Servicing Instructions",
   "source_doc": "6 720 806 944 (2016/07)",
   "source_pages": "pp. 65–68, section 8.1.2 Error codes (Table 48)",
   "source_url": "https://www.worcester-bosch.co.uk/support/literature/download/6720806944",
   "source_type": "manufacturer"
  },
  {
   "id": "worcester-f0290",
   "code": "F0 290",
   "brand": "Worcester Bosch",
   "model_range": "Greenstar i ErP (Greenstar 25i / 30i combi)",
   "category": "PCB / electrical",
   "meaning": "Control box fault (analogue/digital reference error).",
   "homeowner_action": "Write down the full code. Check the boiler has power and nothing else in the house has tripped, then switch the boiler off and on at its mains switch or press reset once. If the code comes back, leave the boiler off.",
   "when_to_call_engineer": "Call a Gas Safe registered engineer if the code returns. Board, wiring and gas valve checks mean opening the casing, so this is engineer-only.",
   "engineer_after_one_reset": true,
   "page_url": "https://combicert.co.uk/boiler-fault-codes/worcester-bosch/#worcester-f0290",
   "source_manual": "Greenstar i ErP Installation, Commissioning and Servicing Instructions",
   "source_doc": "6 720 806 944 (2016/07)",
   "source_pages": "pp. 65–68, section 8.1.2 Error codes (Table 48)",
   "source_url": "https://www.worcester-bosch.co.uk/support/literature/download/6720806944",
   "source_type": "manufacturer"
  },
  {
   "id": "worcester-a8361",
   "code": "A8 361",
   "brand": "Worcester Bosch",
   "model_range": "Greenstar i ErP (Greenstar 25i / 30i combi)",
   "category": "PCB / electrical",
   "meaning": "The fitted code plug (HCM) does not match the control box or display.",
   "homeowner_action": "Write down the full code. Check the boiler has power and nothing else in the house has tripped, then switch the boiler off and on at its mains switch or press reset once. If the code comes back, leave the boiler off.",
   "when_to_call_engineer": "Call a Gas Safe registered engineer if the code returns. Board, wiring and gas valve checks mean opening the casing, so this is engineer-only.",
   "engineer_after_one_reset": true,
   "page_url": "https://combicert.co.uk/boiler-fault-codes/worcester-bosch/#worcester-a8361",
   "source_manual": "Greenstar i ErP Installation, Commissioning and Servicing Instructions",
   "source_doc": "6 720 806 944 (2016/07)",
   "source_pages": "pp. 65–68, section 8.1.2 Error codes (Table 48)",
   "source_url": "https://www.worcester-bosch.co.uk/support/literature/download/6720806944",
   "source_type": "manufacturer"
  },
  {
   "id": "worcester-c4273",
   "code": "C4 273",
   "brand": "Worcester Bosch",
   "model_range": "Greenstar i ErP (Greenstar 25i / 30i combi)",
   "category": "Other / controls",
   "meaning": "The boiler has run continuously for 24 hours and is pausing for a short self-check.",
   "homeowner_action": "Nothing to do. The boiler pauses for a few minutes after 24 hours of non-stop running and then carries on.",
   "when_to_call_engineer": "Call a Gas Safe registered engineer only if the boiler does not restart by itself.",
   "engineer_after_one_reset": false,
   "page_url": "https://combicert.co.uk/boiler-fault-codes/worcester-bosch/#worcester-c4273",
   "source_manual": "Greenstar i ErP Installation, Commissioning and Servicing Instructions",
   "source_doc": "6 720 806 944 (2016/07)",
   "source_pages": "pp. 65–68, section 8.1.2 Error codes (Table 48)",
   "source_url": "https://www.worcester-bosch.co.uk/support/literature/download/6720806944",
   "source_type": "manufacturer"
  },
  {
   "id": "worcester-4000-227",
   "code": "227",
   "brand": "Worcester Bosch",
   "model_range": "Greenstar 4000 (GR4700iW C combi)",
   "category": "Ignition / flame",
   "meaning": "The boiler tried to light but did not detect a flame after ignition, so it locked out.",
   "homeowner_action": "Check another gas appliance such as the hob works, the gas meter valve is on and, on a prepayment meter, there is credit. In freezing weather, check the plastic condensate pipe outside: if it is frozen, pour warm (not boiling) water along it. Then press reset once. If the code comes back, stop resetting.",
   "when_to_call_engineer": "Call a Gas Safe registered engineer if the gas supply is fine and the code returns after one reset. Ignition and flame faults involve gas, so this is engineer-only.",
   "engineer_after_one_reset": false,
   "page_url": "https://combicert.co.uk/boiler-fault-codes/worcester-bosch/#worcester-4000-227",
   "source_manual": "Greenstar 4000 Installation and Maintenance Instructions (GR4700iW C)",
   "source_doc": "6 720 891 161 (2021/10) UK/IE",
   "source_pages": "pp. 71–75, section 10.1.2 Operating/Fault code table",
   "source_url": "https://www.worcester-bosch.co.uk/support/literature/download/6720891161",
   "source_type": "manufacturer"
  },
  {
   "id": "worcester-4000-228",
   "code": "228",
   "brand": "Worcester Bosch",
   "model_range": "Greenstar 4000 (GR4700iW C combi)",
   "category": "Ignition / flame",
   "meaning": "The boiler is seeing a flame signal when there should not be a flame.",
   "homeowner_action": "There is no homeowner check that fixes this code. Write down the full code, press reset once, and if it comes back leave the boiler off.",
   "when_to_call_engineer": "Call a Gas Safe registered engineer if the code comes back after one reset. Ignition and flame faults involve gas, so this is engineer-only.",
   "engineer_after_one_reset": true,
   "page_url": "https://combicert.co.uk/boiler-fault-codes/worcester-bosch/#worcester-4000-228",
   "source_manual": "Greenstar 4000 Installation and Maintenance Instructions (GR4700iW C)",
   "source_doc": "6 720 891 161 (2021/10) UK/IE",
   "source_pages": "pp. 71–75, section 10.1.2 Operating/Fault code table",
   "source_url": "https://www.worcester-bosch.co.uk/support/literature/download/6720891161",
   "source_type": "manufacturer"
  },
  {
   "id": "worcester-4000-234",
   "code": "234",
   "brand": "Worcester Bosch",
   "model_range": "Greenstar 4000 (GR4700iW C combi)",
   "category": "Ignition / flame",
   "meaning": "The boiler has detected an electrical fault with the gas valve.",
   "homeowner_action": "There is no homeowner check that fixes this code. Write down the full code, press reset once, and if it comes back leave the boiler off.",
   "when_to_call_engineer": "Call a Gas Safe registered engineer if the code comes back after one reset. Ignition and flame faults involve gas, so this is engineer-only.",
   "engineer_after_one_reset": true,
   "page_url": "https://combicert.co.uk/boiler-fault-codes/worcester-bosch/#worcester-4000-234",
   "source_manual": "Greenstar 4000 Installation and Maintenance Instructions (GR4700iW C)",
   "source_doc": "6 720 891 161 (2021/10) UK/IE",
   "source_pages": "pp. 71–75, section 10.1.2 Operating/Fault code table",
   "source_url": "https://www.worcester-bosch.co.uk/support/literature/download/6720891161",
   "source_type": "manufacturer"
  },
  {
   "id": "worcester-4000-269",
   "code": "269",
   "brand": "Worcester Bosch",
   "model_range": "Greenstar 4000 (GR4700iW C combi)",
   "category": "Ignition / flame",
   "meaning": "A fault has been detected in the flame monitoring circuit.",
   "homeowner_action": "There is no homeowner check that fixes this code. Write down the full code, press reset once, and if it comes back leave the boiler off.",
   "when_to_call_engineer": "Call a Gas Safe registered engineer if the code comes back after one reset. Ignition and flame faults involve gas, so this is engineer-only.",
   "engineer_after_one_reset": true,
   "page_url": "https://combicert.co.uk/boiler-fault-codes/worcester-bosch/#worcester-4000-269",
   "source_manual": "Greenstar 4000 Installation and Maintenance Instructions (GR4700iW C)",
   "source_doc": "6 720 891 161 (2021/10) UK/IE",
   "source_pages": "pp. 71–75, section 10.1.2 Operating/Fault code table",
   "source_url": "https://www.worcester-bosch.co.uk/support/literature/download/6720891161",
   "source_type": "manufacturer"
  },
  {
   "id": "worcester-4000-306",
   "code": "306",
   "brand": "Worcester Bosch",
   "model_range": "Greenstar 4000 (GR4700iW C combi)",
   "category": "Ignition / flame",
   "meaning": "A flame signal is still detected after the gas supply has been shut off.",
   "homeowner_action": "There is no homeowner check that fixes this code. Write down the full code, press reset once, and if it comes back leave the boiler off.",
   "when_to_call_engineer": "Call a Gas Safe registered engineer if the code comes back after one reset. Ignition and flame faults involve gas, so this is engineer-only.",
   "engineer_after_one_reset": true,
   "page_url": "https://combicert.co.uk/boiler-fault-codes/worcester-bosch/#worcester-4000-306",
   "source_manual": "Greenstar 4000 Installation and Maintenance Instructions (GR4700iW C)",
   "source_doc": "6 720 891 161 (2021/10) UK/IE",
   "source_pages": "pp. 71–75, section 10.1.2 Operating/Fault code table",
   "source_url": "https://www.worcester-bosch.co.uk/support/literature/download/6720891161",
   "source_type": "manufacturer"
  },
  {
   "id": "worcester-4000-363",
   "code": "363",
   "brand": "Worcester Bosch",
   "model_range": "Greenstar 4000 (GR4700iW C combi)",
   "category": "Ignition / flame",
   "meaning": "System fault in the boiler electronics linked to flame (ionisation) measurement.",
   "homeowner_action": "There is no homeowner check that fixes this code. Write down the full code, press reset once, and if it comes back leave the boiler off.",
   "when_to_call_engineer": "Call a Gas Safe registered engineer if the code comes back after one reset. Ignition and flame faults involve gas, so this is engineer-only.",
   "engineer_after_one_reset": true,
   "page_url": "https://combicert.co.uk/boiler-fault-codes/worcester-bosch/#worcester-4000-363",
   "source_manual": "Greenstar 4000 Installation and Maintenance Instructions (GR4700iW C)",
   "source_doc": "6 720 891 161 (2021/10) UK/IE",
   "source_pages": "pp. 71–75, section 10.1.2 Operating/Fault code table",
   "source_url": "https://www.worcester-bosch.co.uk/support/literature/download/6720891161",
   "source_type": "manufacturer"
  },
  {
   "id": "worcester-4000-2916",
   "code": "2916",
   "brand": "Worcester Bosch",
   "model_range": "Greenstar 4000 (GR4700iW C combi)",
   "category": "Ignition / flame",
   "meaning": "The gas valve was detected as open during the post-purge period.",
   "homeowner_action": "There is no homeowner check that fixes this code. Write down the full code, press reset once, and if it comes back leave the boiler off.",
   "when_to_call_engineer": "Call a Gas Safe registered engineer if the code comes back after one reset. Ignition and flame faults involve gas, so this is engineer-only.",
   "engineer_after_one_reset": true,
   "page_url": "https://combicert.co.uk/boiler-fault-codes/worcester-bosch/#worcester-4000-2916",
   "source_manual": "Greenstar 4000 Installation and Maintenance Instructions (GR4700iW C)",
   "source_doc": "6 720 891 161 (2021/10) UK/IE",
   "source_pages": "pp. 71–75, section 10.1.2 Operating/Fault code table",
   "source_url": "https://www.worcester-bosch.co.uk/support/literature/download/6720891161",
   "source_type": "manufacturer"
  },
  {
   "id": "worcester-4000-2920",
   "code": "2920",
   "brand": "Worcester Bosch",
   "model_range": "Greenstar 4000 (GR4700iW C combi)",
   "category": "Ignition / flame",
   "meaning": "Fault in the flame monitoring system.",
   "homeowner_action": "There is no homeowner check that fixes this code. Write down the full code, press reset once, and if it comes back leave the boiler off.",
   "when_to_call_engineer": "Call a Gas Safe registered engineer if the code comes back after one reset. Ignition and flame faults involve gas, so this is engineer-only.",
   "engineer_after_one_reset": true,
   "page_url": "https://combicert.co.uk/boiler-fault-codes/worcester-bosch/#worcester-4000-2920",
   "source_manual": "Greenstar 4000 Installation and Maintenance Instructions (GR4700iW C)",
   "source_doc": "6 720 891 161 (2021/10) UK/IE",
   "source_pages": "pp. 71–75, section 10.1.2 Operating/Fault code table",
   "source_url": "https://www.worcester-bosch.co.uk/support/literature/download/6720891161",
   "source_type": "manufacturer"
  },
  {
   "id": "worcester-4000-2923",
   "code": "2923",
   "brand": "Worcester Bosch",
   "model_range": "Greenstar 4000 (GR4700iW C combi)",
   "category": "Ignition / flame",
   "meaning": "Unexpected feedback from the modulating gas valve.",
   "homeowner_action": "There is no homeowner check that fixes this code. Write down the full code, press reset once, and if it comes back leave the boiler off.",
   "when_to_call_engineer": "Call a Gas Safe registered engineer if the code comes back after one reset. Ignition and flame faults involve gas, so this is engineer-only.",
   "engineer_after_one_reset": true,
   "page_url": "https://combicert.co.uk/boiler-fault-codes/worcester-bosch/#worcester-4000-2923",
   "source_manual": "Greenstar 4000 Installation and Maintenance Instructions (GR4700iW C)",
   "source_doc": "6 720 891 161 (2021/10) UK/IE",
   "source_pages": "pp. 71–75, section 10.1.2 Operating/Fault code table",
   "source_url": "https://www.worcester-bosch.co.uk/support/literature/download/6720891161",
   "source_type": "manufacturer"
  },
  {
   "id": "worcester-4000-281",
   "code": "281",
   "brand": "Worcester Bosch",
   "model_range": "Greenstar 4000 (GR4700iW C combi)",
   "category": "Water pressure / circulation",
   "meaning": "The pump appears to be stuck or running with air instead of water.",
   "homeowner_action": "There is no homeowner check that fixes this code. Write down the full code, press reset once, and if it comes back leave the boiler off.",
   "when_to_call_engineer": "Call a Gas Safe registered engineer if you have to top up more than once every few months, the gauge goes above about 2.5 bar when hot, water drips from the outside overflow pipe, or the code returns after topping up.",
   "engineer_after_one_reset": true,
   "page_url": "https://combicert.co.uk/boiler-fault-codes/worcester-bosch/#worcester-4000-281",
   "source_manual": "Greenstar 4000 Installation and Maintenance Instructions (GR4700iW C)",
   "source_doc": "6 720 891 161 (2021/10) UK/IE",
   "source_pages": "pp. 71–75, section 10.1.2 Operating/Fault code table",
   "source_url": "https://www.worcester-bosch.co.uk/support/literature/download/6720891161",
   "source_type": "manufacturer"
  },
  {
   "id": "worcester-4000-1017",
   "code": "1017",
   "brand": "Worcester Bosch",
   "model_range": "Greenstar 4000 (GR4700iW C combi)",
   "category": "Water pressure / circulation",
   "meaning": "Maintenance warning: system water pressure is too low.",
   "homeowner_action": "Look at the pressure gauge while the boiler is cold. If it is below about 1 bar, top it up with the filling loop exactly as your user guide shows, to about 1–1.5 bar or the figure in your guide, then close the loop fully. Check the radiator valves are open, then press reset once.",
   "when_to_call_engineer": "Call a Gas Safe registered engineer if you have to top up more than once every few months, the gauge goes above about 2.5 bar when hot, water drips from the outside overflow pipe, or the code returns after topping up.",
   "engineer_after_one_reset": false,
   "page_url": "https://combicert.co.uk/boiler-fault-codes/worcester-bosch/#worcester-4000-1017",
   "source_manual": "Greenstar 4000 Installation and Maintenance Instructions (GR4700iW C)",
   "source_doc": "6 720 891 161 (2021/10) UK/IE",
   "source_pages": "pp. 71–75, section 10.1.2 Operating/Fault code table",
   "source_url": "https://www.worcester-bosch.co.uk/support/literature/download/6720891161",
   "source_type": "manufacturer"
  },
  {
   "id": "worcester-4000-224",
   "code": "224",
   "brand": "Worcester Bosch",
   "model_range": "Greenstar 4000 (GR4700iW C combi)",
   "category": "Temperature / overheat",
   "meaning": "A safety overheat device on the flue or heat exchanger has tripped. Short-lived it blocks the boiler; if it persists it becomes a lockout.",
   "homeowner_action": "Let the boiler cool for 20 to 30 minutes, then press reset once. If the code comes back, leave the boiler off.",
   "when_to_call_engineer": "Call a Gas Safe registered engineer if the code comes back after one reset. Overheat shut-downs are safety devices doing their job, so this is engineer-only.",
   "engineer_after_one_reset": true,
   "page_url": "https://combicert.co.uk/boiler-fault-codes/worcester-bosch/#worcester-4000-224",
   "source_manual": "Greenstar 4000 Installation and Maintenance Instructions (GR4700iW C)",
   "source_doc": "6 720 891 161 (2021/10) UK/IE",
   "source_pages": "pp. 71–75, section 10.1.2 Operating/Fault code table",
   "source_url": "https://www.worcester-bosch.co.uk/support/literature/download/6720891161",
   "source_type": "manufacturer"
  },
  {
   "id": "worcester-4000-214",
   "code": "214",
   "brand": "Worcester Bosch",
   "model_range": "Greenstar 4000 (GR4700iW C combi)",
   "category": "Flue / fan / air",
   "meaning": "The fan stopped while the boiler was in its ignition safety period, so the boiler locked out.",
   "homeowner_action": "There is no homeowner check that fixes this code. Write down the full code, press reset once, and if it comes back leave the boiler off.",
   "when_to_call_engineer": "Call a Gas Safe registered engineer if the terminal looks clear and the code returns. Flue and fan faults can affect how combustion gases leave your home, so this is engineer-only.",
   "engineer_after_one_reset": true,
   "page_url": "https://combicert.co.uk/boiler-fault-codes/worcester-bosch/#worcester-4000-214",
   "source_manual": "Greenstar 4000 Installation and Maintenance Instructions (GR4700iW C)",
   "source_doc": "6 720 891 161 (2021/10) UK/IE",
   "source_pages": "pp. 71–75, section 10.1.2 Operating/Fault code table",
   "source_url": "https://www.worcester-bosch.co.uk/support/literature/download/6720891161",
   "source_type": "manufacturer"
  },
  {
   "id": "worcester-4000-2910",
   "code": "2910",
   "brand": "Worcester Bosch",
   "model_range": "Greenstar 4000 (GR4700iW C combi)",
   "category": "Flue / fan / air",
   "meaning": "The boiler has detected a problem in the flue system.",
   "homeowner_action": "There is no homeowner check that fixes this code. Write down the full code, press reset once, and if it comes back leave the boiler off.",
   "when_to_call_engineer": "Call a Gas Safe registered engineer if the terminal looks clear and the code returns. Flue and fan faults can affect how combustion gases leave your home, so this is engineer-only.",
   "engineer_after_one_reset": true,
   "page_url": "https://combicert.co.uk/boiler-fault-codes/worcester-bosch/#worcester-4000-2910",
   "source_manual": "Greenstar 4000 Installation and Maintenance Instructions (GR4700iW C)",
   "source_doc": "6 720 891 161 (2021/10) UK/IE",
   "source_pages": "pp. 71–75, section 10.1.2 Operating/Fault code table",
   "source_url": "https://www.worcester-bosch.co.uk/support/literature/download/6720891161",
   "source_type": "manufacturer"
  },
  {
   "id": "worcester-4000-2915",
   "code": "2915",
   "brand": "Worcester Bosch",
   "model_range": "Greenstar 4000 (GR4700iW C combi)",
   "category": "Flue / fan / air",
   "meaning": "The fan keeps running after the post-purge period has ended.",
   "homeowner_action": "There is no homeowner check that fixes this code. Write down the full code, press reset once, and if it comes back leave the boiler off.",
   "when_to_call_engineer": "Call a Gas Safe registered engineer if the terminal looks clear and the code returns. Flue and fan faults can affect how combustion gases leave your home, so this is engineer-only.",
   "engineer_after_one_reset": true,
   "page_url": "https://combicert.co.uk/boiler-fault-codes/worcester-bosch/#worcester-4000-2915",
   "source_manual": "Greenstar 4000 Installation and Maintenance Instructions (GR4700iW C)",
   "source_doc": "6 720 891 161 (2021/10) UK/IE",
   "source_pages": "pp. 71–75, section 10.1.2 Operating/Fault code table",
   "source_url": "https://www.worcester-bosch.co.uk/support/literature/download/6720891161",
   "source_type": "manufacturer"
  },
  {
   "id": "worcester-4000-1021",
   "code": "1021",
   "brand": "Worcester Bosch",
   "model_range": "Greenstar 4000 (GR4700iW C combi)",
   "category": "Sensors / thermistors",
   "meaning": "Fault with the hot water temperature sensor; hot water is affected.",
   "homeowner_action": "Write down the full code. Check the boiler has power, then switch it off and on at its mains switch or press reset once. If the code comes back, leave it there: sensors are inside the casing.",
   "when_to_call_engineer": "Call a Gas Safe registered engineer if the code returns. Testing and replacing sensors means opening the casing, so this is engineer-only.",
   "engineer_after_one_reset": true,
   "page_url": "https://combicert.co.uk/boiler-fault-codes/worcester-bosch/#worcester-4000-1021",
   "source_manual": "Greenstar 4000 Installation and Maintenance Instructions (GR4700iW C)",
   "source_doc": "6 720 891 161 (2021/10) UK/IE",
   "source_pages": "pp. 71–75, section 10.1.2 Operating/Fault code table",
   "source_url": "https://www.worcester-bosch.co.uk/support/literature/download/6720891161",
   "source_type": "manufacturer"
  },
  {
   "id": "worcester-4000-1037",
   "code": "1037",
   "brand": "Worcester Bosch",
   "model_range": "Greenstar 4000 (GR4700iW C combi)",
   "category": "Sensors / thermistors",
   "meaning": "Outdoor (weather) sensor fault; the boiler runs in a back-up heating mode.",
   "homeowner_action": "Nothing urgent: the boiler normally keeps heating without the outdoor sensor, using a fixed setting. Press reset once to see if it clears.",
   "when_to_call_engineer": "Call a Gas Safe registered engineer if the code returns. Testing and replacing sensors means opening the casing, so this is engineer-only.",
   "engineer_after_one_reset": true,
   "page_url": "https://combicert.co.uk/boiler-fault-codes/worcester-bosch/#worcester-4000-1037",
   "source_manual": "Greenstar 4000 Installation and Maintenance Instructions (GR4700iW C)",
   "source_doc": "6 720 891 161 (2021/10) UK/IE",
   "source_pages": "pp. 71–75, section 10.1.2 Operating/Fault code table",
   "source_url": "https://www.worcester-bosch.co.uk/support/literature/download/6720891161",
   "source_type": "manufacturer"
  },
  {
   "id": "worcester-4000-1065",
   "code": "1065",
   "brand": "Worcester Bosch",
   "model_range": "Greenstar 4000 (GR4700iW C combi)",
   "category": "Sensors / thermistors",
   "meaning": "The system pressure sensor is faulty or not connected.",
   "homeowner_action": "Write down the full code. Check the boiler has power, then switch it off and on at its mains switch or press reset once. If the code comes back, leave it there: sensors are inside the casing.",
   "when_to_call_engineer": "Call a Gas Safe registered engineer if the code returns. Testing and replacing sensors means opening the casing, so this is engineer-only.",
   "engineer_after_one_reset": true,
   "page_url": "https://combicert.co.uk/boiler-fault-codes/worcester-bosch/#worcester-4000-1065",
   "source_manual": "Greenstar 4000 Installation and Maintenance Instructions (GR4700iW C)",
   "source_doc": "6 720 891 161 (2021/10) UK/IE",
   "source_pages": "pp. 71–75, section 10.1.2 Operating/Fault code table",
   "source_url": "https://www.worcester-bosch.co.uk/support/literature/download/6720891161",
   "source_type": "manufacturer"
  },
  {
   "id": "worcester-4000-1073",
   "code": "1073",
   "brand": "Worcester Bosch",
   "model_range": "Greenstar 4000 (GR4700iW C combi)",
   "category": "Sensors / thermistors",
   "meaning": "The flow temperature sensor reads as a short circuit.",
   "homeowner_action": "Write down the full code. Check the boiler has power, then switch it off and on at its mains switch or press reset once. If the code comes back, leave it there: sensors are inside the casing.",
   "when_to_call_engineer": "Call a Gas Safe registered engineer if the code returns. Testing and replacing sensors means opening the casing, so this is engineer-only.",
   "engineer_after_one_reset": true,
   "page_url": "https://combicert.co.uk/boiler-fault-codes/worcester-bosch/#worcester-4000-1073",
   "source_manual": "Greenstar 4000 Installation and Maintenance Instructions (GR4700iW C)",
   "source_doc": "6 720 891 161 (2021/10) UK/IE",
   "source_pages": "pp. 71–75, section 10.1.2 Operating/Fault code table",
   "source_url": "https://www.worcester-bosch.co.uk/support/literature/download/6720891161",
   "source_type": "manufacturer"
  },
  {
   "id": "worcester-4000-1074",
   "code": "1074",
   "brand": "Worcester Bosch",
   "model_range": "Greenstar 4000 (GR4700iW C combi)",
   "category": "Sensors / thermistors",
   "meaning": "No signal from the flow temperature sensor (open circuit).",
   "homeowner_action": "Write down the full code. Check the boiler has power, then switch it off and on at its mains switch or press reset once. If the code comes back, leave it there: sensors are inside the casing.",
   "when_to_call_engineer": "Call a Gas Safe registered engineer if the code returns. Testing and replacing sensors means opening the casing, so this is engineer-only.",
   "engineer_after_one_reset": true,
   "page_url": "https://combicert.co.uk/boiler-fault-codes/worcester-bosch/#worcester-4000-1074",
   "source_manual": "Greenstar 4000 Installation and Maintenance Instructions (GR4700iW C)",
   "source_doc": "6 720 891 161 (2021/10) UK/IE",
   "source_pages": "pp. 71–75, section 10.1.2 Operating/Fault code table",
   "source_url": "https://www.worcester-bosch.co.uk/support/literature/download/6720891161",
   "source_type": "manufacturer"
  },
  {
   "id": "worcester-4000-1075",
   "code": "1075",
   "brand": "Worcester Bosch",
   "model_range": "Greenstar 4000 (GR4700iW C combi)",
   "category": "Sensors / thermistors",
   "meaning": "The heat exchanger temperature sensor reads as a short circuit.",
   "homeowner_action": "Write down the full code. Check the boiler has power, then switch it off and on at its mains switch or press reset once. If the code comes back, leave it there: sensors are inside the casing.",
   "when_to_call_engineer": "Call a Gas Safe registered engineer if the code returns. Testing and replacing sensors means opening the casing, so this is engineer-only.",
   "engineer_after_one_reset": true,
   "page_url": "https://combicert.co.uk/boiler-fault-codes/worcester-bosch/#worcester-4000-1075",
   "source_manual": "Greenstar 4000 Installation and Maintenance Instructions (GR4700iW C)",
   "source_doc": "6 720 891 161 (2021/10) UK/IE",
   "source_pages": "pp. 71–75, section 10.1.2 Operating/Fault code table",
   "source_url": "https://www.worcester-bosch.co.uk/support/literature/download/6720891161",
   "source_type": "manufacturer"
  },
  {
   "id": "worcester-4000-1076",
   "code": "1076",
   "brand": "Worcester Bosch",
   "model_range": "Greenstar 4000 (GR4700iW C combi)",
   "category": "Sensors / thermistors",
   "meaning": "The heat exchanger temperature sensor is disconnected.",
   "homeowner_action": "Write down the full code. Check the boiler has power, then switch it off and on at its mains switch or press reset once. If the code comes back, leave it there: sensors are inside the casing.",
   "when_to_call_engineer": "Call a Gas Safe registered engineer if the code returns. Testing and replacing sensors means opening the casing, so this is engineer-only.",
   "engineer_after_one_reset": true,
   "page_url": "https://combicert.co.uk/boiler-fault-codes/worcester-bosch/#worcester-4000-1076",
   "source_manual": "Greenstar 4000 Installation and Maintenance Instructions (GR4700iW C)",
   "source_doc": "6 720 891 161 (2021/10) UK/IE",
   "source_pages": "pp. 71–75, section 10.1.2 Operating/Fault code table",
   "source_url": "https://www.worcester-bosch.co.uk/support/literature/download/6720891161",
   "source_type": "manufacturer"
  },
  {
   "id": "worcester-4000-233",
   "code": "233",
   "brand": "Worcester Bosch",
   "model_range": "Greenstar 4000 (GR4700iW C combi)",
   "category": "PCB / electrical",
   "meaning": "The boiler's identification (code) plug or electronics are not recognised.",
   "homeowner_action": "Write down the full code. Check the boiler has power and nothing else in the house has tripped, then switch the boiler off and on at its mains switch or press reset once. If the code comes back, leave the boiler off.",
   "when_to_call_engineer": "Call a Gas Safe registered engineer if the code returns. Board, wiring and gas valve checks mean opening the casing, so this is engineer-only.",
   "engineer_after_one_reset": true,
   "page_url": "https://combicert.co.uk/boiler-fault-codes/worcester-bosch/#worcester-4000-233",
   "source_manual": "Greenstar 4000 Installation and Maintenance Instructions (GR4700iW C)",
   "source_doc": "6 720 891 161 (2021/10) UK/IE",
   "source_pages": "pp. 71–75, section 10.1.2 Operating/Fault code table",
   "source_url": "https://www.worcester-bosch.co.uk/support/literature/download/6720891161",
   "source_type": "manufacturer"
  },
  {
   "id": "worcester-4000-235",
   "code": "235",
   "brand": "Worcester Bosch",
   "model_range": "Greenstar 4000 (GR4700iW C combi)",
   "category": "PCB / electrical",
   "meaning": "The software versions of the boiler electronics and the code plug do not match.",
   "homeowner_action": "Write down the full code. Check the boiler has power and nothing else in the house has tripped, then switch the boiler off and on at its mains switch or press reset once. If the code comes back, leave the boiler off.",
   "when_to_call_engineer": "Call a Gas Safe registered engineer if the code returns. Board, wiring and gas valve checks mean opening the casing, so this is engineer-only.",
   "engineer_after_one_reset": true,
   "page_url": "https://combicert.co.uk/boiler-fault-codes/worcester-bosch/#worcester-4000-235",
   "source_manual": "Greenstar 4000 Installation and Maintenance Instructions (GR4700iW C)",
   "source_doc": "6 720 891 161 (2021/10) UK/IE",
   "source_pages": "pp. 71–75, section 10.1.2 Operating/Fault code table",
   "source_url": "https://www.worcester-bosch.co.uk/support/literature/download/6720891161",
   "source_type": "manufacturer"
  },
  {
   "id": "worcester-4000-238",
   "code": "238",
   "brand": "Worcester Bosch",
   "model_range": "Greenstar 4000 (GR4700iW C combi)",
   "category": "PCB / electrical",
   "meaning": "The boiler electronics have reported a fault, which the manual links to the gas valve circuit.",
   "homeowner_action": "Write down the full code. Check the boiler has power and nothing else in the house has tripped, then switch the boiler off and on at its mains switch or press reset once. If the code comes back, leave the boiler off.",
   "when_to_call_engineer": "Call a Gas Safe registered engineer if the code returns. Board, wiring and gas valve checks mean opening the casing, so this is engineer-only.",
   "engineer_after_one_reset": true,
   "page_url": "https://combicert.co.uk/boiler-fault-codes/worcester-bosch/#worcester-4000-238",
   "source_manual": "Greenstar 4000 Installation and Maintenance Instructions (GR4700iW C)",
   "source_doc": "6 720 891 161 (2021/10) UK/IE",
   "source_pages": "pp. 71–75, section 10.1.2 Operating/Fault code table",
   "source_url": "https://www.worcester-bosch.co.uk/support/literature/download/6720891161",
   "source_type": "manufacturer"
  },
  {
   "id": "worcester-4000-242",
   "code": "242",
   "brand": "Worcester Bosch",
   "model_range": "Greenstar 4000 (GR4700iW C combi)",
   "category": "PCB / electrical",
   "meaning": "Internal system fault in the boiler electronics.",
   "homeowner_action": "Write down the full code. Check the boiler has power and nothing else in the house has tripped, then switch the boiler off and on at its mains switch or press reset once. If the code comes back, leave the boiler off.",
   "when_to_call_engineer": "Call a Gas Safe registered engineer if the code returns. Board, wiring and gas valve checks mean opening the casing, so this is engineer-only.",
   "engineer_after_one_reset": true,
   "page_url": "https://combicert.co.uk/boiler-fault-codes/worcester-bosch/#worcester-4000-242",
   "source_manual": "Greenstar 4000 Installation and Maintenance Instructions (GR4700iW C)",
   "source_doc": "6 720 891 161 (2021/10) UK/IE",
   "source_pages": "pp. 71–75, section 10.1.2 Operating/Fault code table",
   "source_url": "https://www.worcester-bosch.co.uk/support/literature/download/6720891161",
   "source_type": "manufacturer"
  },
  {
   "id": "worcester-4000-360",
   "code": "360",
   "brand": "Worcester Bosch",
   "model_range": "Greenstar 4000 (GR4700iW C combi)",
   "category": "PCB / electrical",
   "meaning": "System fault in the boiler electronics, linked by the manual to the code plug.",
   "homeowner_action": "Write down the full code. Check the boiler has power and nothing else in the house has tripped, then switch the boiler off and on at its mains switch or press reset once. If the code comes back, leave the boiler off.",
   "when_to_call_engineer": "Call a Gas Safe registered engineer if the code returns. Board, wiring and gas valve checks mean opening the casing, so this is engineer-only.",
   "engineer_after_one_reset": true,
   "page_url": "https://combicert.co.uk/boiler-fault-codes/worcester-bosch/#worcester-4000-360",
   "source_manual": "Greenstar 4000 Installation and Maintenance Instructions (GR4700iW C)",
   "source_doc": "6 720 891 161 (2021/10) UK/IE",
   "source_pages": "pp. 71–75, section 10.1.2 Operating/Fault code table",
   "source_url": "https://www.worcester-bosch.co.uk/support/literature/download/6720891161",
   "source_type": "manufacturer"
  },
  {
   "id": "worcester-4000-2085",
   "code": "2085",
   "brand": "Worcester Bosch",
   "model_range": "Greenstar 4000 (GR4700iW C combi)",
   "category": "PCB / electrical",
   "meaning": "Internal fault in the boiler.",
   "homeowner_action": "Write down the full code. Check the boiler has power and nothing else in the house has tripped, then switch the boiler off and on at its mains switch or press reset once. If the code comes back, leave the boiler off.",
   "when_to_call_engineer": "Call a Gas Safe registered engineer if the code returns. Board, wiring and gas valve checks mean opening the casing, so this is engineer-only.",
   "engineer_after_one_reset": true,
   "page_url": "https://combicert.co.uk/boiler-fault-codes/worcester-bosch/#worcester-4000-2085",
   "source_manual": "Greenstar 4000 Installation and Maintenance Instructions (GR4700iW C)",
   "source_doc": "6 720 891 161 (2021/10) UK/IE",
   "source_pages": "pp. 71–75, section 10.1.2 Operating/Fault code table",
   "source_url": "https://www.worcester-bosch.co.uk/support/literature/download/6720891161",
   "source_type": "manufacturer"
  },
  {
   "id": "worcester-4000-2908",
   "code": "2908",
   "brand": "Worcester Bosch",
   "model_range": "Greenstar 4000 (GR4700iW C combi)",
   "category": "PCB / electrical",
   "meaning": "System fault in the burner controller.",
   "homeowner_action": "Write down the full code. Check the boiler has power and nothing else in the house has tripped, then switch the boiler off and on at its mains switch or press reset once. If the code comes back, leave the boiler off.",
   "when_to_call_engineer": "Call a Gas Safe registered engineer if the code returns. Board, wiring and gas valve checks mean opening the casing, so this is engineer-only.",
   "engineer_after_one_reset": true,
   "page_url": "https://combicert.co.uk/boiler-fault-codes/worcester-bosch/#worcester-4000-2908",
   "source_manual": "Greenstar 4000 Installation and Maintenance Instructions (GR4700iW C)",
   "source_doc": "6 720 891 161 (2021/10) UK/IE",
   "source_pages": "pp. 71–75, section 10.1.2 Operating/Fault code table",
   "source_url": "https://www.worcester-bosch.co.uk/support/literature/download/6720891161",
   "source_type": "manufacturer"
  },
  {
   "id": "worcester-4000-232",
   "code": "232",
   "brand": "Worcester Bosch",
   "model_range": "Greenstar 4000 (GR4700iW C combi)",
   "category": "Other / controls",
   "meaning": "The boiler is being held off by an external switching contact.",
   "homeowner_action": "Check any external control wired to the boiler, such as a timer, frost stat or switch, is on.",
   "when_to_call_engineer": "Call a Gas Safe registered engineer if the code stays after you have checked the controls, or keeps coming back.",
   "engineer_after_one_reset": false,
   "page_url": "https://combicert.co.uk/boiler-fault-codes/worcester-bosch/#worcester-4000-232",
   "source_manual": "Greenstar 4000 Installation and Maintenance Instructions (GR4700iW C)",
   "source_doc": "6 720 891 161 (2021/10) UK/IE",
   "source_pages": "pp. 71–75, section 10.1.2 Operating/Fault code table",
   "source_url": "https://www.worcester-bosch.co.uk/support/literature/download/6720891161",
   "source_type": "manufacturer"
  },
  {
   "id": "worcester-4000-1010",
   "code": "1010",
   "brand": "Worcester Bosch",
   "model_range": "Greenstar 4000 (GR4700iW C combi)",
   "category": "Other / controls",
   "meaning": "The boiler has lost communication with a connected control over the EMS bus.",
   "homeowner_action": "Check your room thermostat or programmer has power or fresh batteries and is set to call for heat. For a wireless control, follow its guide to reconnect it. Then press reset once.",
   "when_to_call_engineer": "Call a Gas Safe registered engineer if the code stays after you have checked the controls, or keeps coming back.",
   "engineer_after_one_reset": false,
   "page_url": "https://combicert.co.uk/boiler-fault-codes/worcester-bosch/#worcester-4000-1010",
   "source_manual": "Greenstar 4000 Installation and Maintenance Instructions (GR4700iW C)",
   "source_doc": "6 720 891 161 (2021/10) UK/IE",
   "source_pages": "pp. 71–75, section 10.1.2 Operating/Fault code table",
   "source_url": "https://www.worcester-bosch.co.uk/support/literature/download/6720891161",
   "source_type": "manufacturer"
  },
  {
   "id": "baxi-h0302",
   "code": "H.03.02",
   "brand": "Baxi",
   "model_range": "Baxi 600 Combi 2 (24 / 30 / 36)",
   "category": "Ignition / flame",
   "meaning": "The flame was lost temporarily.",
   "homeowner_action": "Check another gas appliance such as the hob works, the gas meter valve is on and, on a prepayment meter, there is credit. In freezing weather, check the plastic condensate pipe outside: if it is frozen, pour warm (not boiling) water along it. Then press reset once. If the code comes back, stop resetting.",
   "when_to_call_engineer": "Call a Gas Safe registered engineer if the gas supply is fine and the code returns after one reset. Ignition and flame faults involve gas, so this is engineer-only.",
   "engineer_after_one_reset": false,
   "page_url": "https://combicert.co.uk/boiler-fault-codes/baxi/#baxi-h0302",
   "source_manual": "Baxi 600 Combi 2 Installation and Service Manual & Boiler Fiche",
   "source_doc": "7796561-03 (04/23)",
   "source_pages": "pp. 73–77, section 11.2 Error codes (Tab. 33 and Tab. 34)",
   "source_url": "https://edge.sitecorecloud.io/bdrthermea1-platform-production-864a/media/Project/BaxiUK/BaxiUK/Files/Product-Literature/Boilers/Combi-boilers/Baxi-600-Combi-2/baxi-600-combi-2-installation-manual.pdf",
   "source_type": "manufacturer"
  },
  {
   "id": "baxi-h0354",
   "code": "H.03.54",
   "brand": "Baxi",
   "model_range": "Baxi 600 Combi 2 (24 / 30 / 36)",
   "category": "Ignition / flame",
   "meaning": "Temporary flame loss, or shutdown because the supply voltage is too low.",
   "homeowner_action": "Check another gas appliance such as the hob works, the gas meter valve is on and, on a prepayment meter, there is credit. In freezing weather, check the plastic condensate pipe outside: if it is frozen, pour warm (not boiling) water along it. Then press reset once. If the code comes back, stop resetting.",
   "when_to_call_engineer": "Call a Gas Safe registered engineer if the gas supply is fine and the code returns after one reset. Ignition and flame faults involve gas, so this is engineer-only.",
   "engineer_after_one_reset": false,
   "page_url": "https://combicert.co.uk/boiler-fault-codes/baxi/#baxi-h0354",
   "source_manual": "Baxi 600 Combi 2 Installation and Service Manual & Boiler Fiche",
   "source_doc": "7796561-03 (04/23)",
   "source_pages": "pp. 73–77, section 11.2 Error codes (Tab. 33 and Tab. 34)",
   "source_url": "https://edge.sitecorecloud.io/bdrthermea1-platform-production-864a/media/Project/BaxiUK/BaxiUK/Files/Product-Literature/Boilers/Combi-boilers/Baxi-600-Combi-2/baxi-600-combi-2-installation-manual.pdf",
   "source_type": "manufacturer"
  },
  {
   "id": "baxi-e0104",
   "code": "E.01.04",
   "brand": "Baxi",
   "model_range": "Baxi 600 Combi 2 (24 / 30 / 36)",
   "category": "Ignition / flame",
   "meaning": "The flame was lost five times in 24 hours with the burner on, so the boiler locked out.",
   "homeowner_action": "Check another gas appliance such as the hob works, the gas meter valve is on and, on a prepayment meter, there is credit. In freezing weather, check the plastic condensate pipe outside: if it is frozen, pour warm (not boiling) water along it. Then press reset once. If the code comes back, stop resetting.",
   "when_to_call_engineer": "Call a Gas Safe registered engineer if the gas supply is fine and the code returns after one reset. Ignition and flame faults involve gas, so this is engineer-only.",
   "engineer_after_one_reset": false,
   "page_url": "https://combicert.co.uk/boiler-fault-codes/baxi/#baxi-e0104",
   "source_manual": "Baxi 600 Combi 2 Installation and Service Manual & Boiler Fiche",
   "source_doc": "7796561-03 (04/23)",
   "source_pages": "pp. 73–77, section 11.2 Error codes (Tab. 33 and Tab. 34)",
   "source_url": "https://edge.sitecorecloud.io/bdrthermea1-platform-production-864a/media/Project/BaxiUK/BaxiUK/Files/Product-Literature/Boilers/Combi-boilers/Baxi-600-Combi-2/baxi-600-combi-2-installation-manual.pdf",
   "source_type": "manufacturer"
  },
  {
   "id": "baxi-e0410",
   "code": "E.04.10",
   "brand": "Baxi",
   "model_range": "Baxi 600 Combi 2 (24 / 30 / 36)",
   "category": "Ignition / flame",
   "meaning": "The burner failed to light after four attempts. This is the 600 Combi 2's ignition lockout.",
   "homeowner_action": "Check another gas appliance such as the hob works, the gas meter valve is on and, on a prepayment meter, there is credit. In freezing weather, check the plastic condensate pipe outside: if it is frozen, pour warm (not boiling) water along it. Then press reset once. If the code comes back, stop resetting.",
   "when_to_call_engineer": "Call a Gas Safe registered engineer if the gas supply is fine and the code returns after one reset. Ignition and flame faults involve gas, so this is engineer-only.",
   "engineer_after_one_reset": false,
   "page_url": "https://combicert.co.uk/boiler-fault-codes/baxi/#baxi-e0410",
   "source_manual": "Baxi 600 Combi 2 Installation and Service Manual & Boiler Fiche",
   "source_doc": "7796561-03 (04/23)",
   "source_pages": "pp. 73–77, section 11.2 Error codes (Tab. 33 and Tab. 34)",
   "source_url": "https://edge.sitecorecloud.io/bdrthermea1-platform-production-864a/media/Project/BaxiUK/BaxiUK/Files/Product-Literature/Boilers/Combi-boilers/Baxi-600-Combi-2/baxi-600-combi-2-installation-manual.pdf",
   "source_type": "manufacturer"
  },
  {
   "id": "baxi-e0412",
   "code": "E.04.12",
   "brand": "Baxi",
   "model_range": "Baxi 600 Combi 2 (24 / 30 / 36)",
   "category": "Ignition / flame",
   "meaning": "Ignition failure while checking for a parasitic (false) flame.",
   "homeowner_action": "There is no homeowner check that fixes this code. Write down the full code, press reset once, and if it comes back leave the boiler off.",
   "when_to_call_engineer": "Call a Gas Safe registered engineer if the code comes back after one reset. Ignition and flame faults involve gas, so this is engineer-only.",
   "engineer_after_one_reset": true,
   "page_url": "https://combicert.co.uk/boiler-fault-codes/baxi/#baxi-e0412",
   "source_manual": "Baxi 600 Combi 2 Installation and Service Manual & Boiler Fiche",
   "source_doc": "7796561-03 (04/23)",
   "source_pages": "pp. 73–77, section 11.2 Error codes (Tab. 33 and Tab. 34)",
   "source_url": "https://edge.sitecorecloud.io/bdrthermea1-platform-production-864a/media/Project/BaxiUK/BaxiUK/Files/Product-Literature/Boilers/Combi-boilers/Baxi-600-Combi-2/baxi-600-combi-2-installation-manual.pdf",
   "source_type": "manufacturer"
  },
  {
   "id": "baxi-e0417",
   "code": "E.04.17",
   "brand": "Baxi",
   "model_range": "Baxi 600 Combi 2 (24 / 30 / 36)",
   "category": "Ignition / flame",
   "meaning": "Fault in the gas valve control circuit.",
   "homeowner_action": "There is no homeowner check that fixes this code. Write down the full code, press reset once, and if it comes back leave the boiler off.",
   "when_to_call_engineer": "Call a Gas Safe registered engineer if the code comes back after one reset. Ignition and flame faults involve gas, so this is engineer-only.",
   "engineer_after_one_reset": true,
   "page_url": "https://combicert.co.uk/boiler-fault-codes/baxi/#baxi-e0417",
   "source_manual": "Baxi 600 Combi 2 Installation and Service Manual & Boiler Fiche",
   "source_doc": "7796561-03 (04/23)",
   "source_pages": "pp. 73–77, section 11.2 Error codes (Tab. 33 and Tab. 34)",
   "source_url": "https://edge.sitecorecloud.io/bdrthermea1-platform-production-864a/media/Project/BaxiUK/BaxiUK/Files/Product-Literature/Boilers/Combi-boilers/Baxi-600-Combi-2/baxi-600-combi-2-installation-manual.pdf",
   "source_type": "manufacturer"
  },
  {
   "id": "baxi-e0454",
   "code": "E.04.54",
   "brand": "Baxi",
   "model_range": "Baxi 600 Combi 2 (24 / 30 / 36)",
   "category": "Ignition / flame",
   "meaning": "Fault in the gas valve control circuit.",
   "homeowner_action": "There is no homeowner check that fixes this code. Write down the full code, press reset once, and if it comes back leave the boiler off.",
   "when_to_call_engineer": "Call a Gas Safe registered engineer if the code comes back after one reset. Ignition and flame faults involve gas, so this is engineer-only.",
   "engineer_after_one_reset": true,
   "page_url": "https://combicert.co.uk/boiler-fault-codes/baxi/#baxi-e0454",
   "source_manual": "Baxi 600 Combi 2 Installation and Service Manual & Boiler Fiche",
   "source_doc": "7796561-03 (04/23)",
   "source_pages": "pp. 73–77, section 11.2 Error codes (Tab. 33 and Tab. 34)",
   "source_url": "https://edge.sitecorecloud.io/bdrthermea1-platform-production-864a/media/Project/BaxiUK/BaxiUK/Files/Product-Literature/Boilers/Combi-boilers/Baxi-600-Combi-2/baxi-600-combi-2-installation-manual.pdf",
   "source_type": "manufacturer"
  },
  {
   "id": "baxi-a0206",
   "code": "A.02.06",
   "brand": "Baxi",
   "model_range": "Baxi 600 Combi 2 (24 / 30 / 36)",
   "category": "Water pressure / circulation",
   "meaning": "Warning: water pressure in the heating system is low.",
   "homeowner_action": "Look at the pressure gauge while the boiler is cold. If it is below about 1 bar, top it up with the filling loop exactly as your user guide shows, to about 1–1.5 bar or the figure in your guide, then close the loop fully. Check the radiator valves are open, then press reset once.",
   "when_to_call_engineer": "Call a Gas Safe registered engineer if you have to top up more than once every few months, the gauge goes above about 2.5 bar when hot, water drips from the outside overflow pipe, or the code returns after topping up.",
   "engineer_after_one_reset": false,
   "page_url": "https://combicert.co.uk/boiler-fault-codes/baxi/#baxi-a0206",
   "source_manual": "Baxi 600 Combi 2 Installation and Service Manual & Boiler Fiche",
   "source_doc": "7796561-03 (04/23)",
   "source_pages": "pp. 73–77, section 11.2 Error codes (Tab. 33 and Tab. 34)",
   "source_url": "https://edge.sitecorecloud.io/bdrthermea1-platform-production-864a/media/Project/BaxiUK/BaxiUK/Files/Product-Literature/Boilers/Combi-boilers/Baxi-600-Combi-2/baxi-600-combi-2-installation-manual.pdf",
   "source_type": "manufacturer"
  },
  {
   "id": "baxi-h0042",
   "code": "H.00.42",
   "brand": "Baxi",
   "model_range": "Baxi 600 Combi 2 (24 / 30 / 36)",
   "category": "Water pressure / circulation",
   "meaning": "The pressure sensor is open circuit or faulty (shown while a reset is in progress).",
   "homeowner_action": "Look at the pressure gauge while the boiler is cold. If it is below about 1 bar, top it up with the filling loop exactly as your user guide shows, to about 1–1.5 bar or the figure in your guide, then close the loop fully. Check the radiator valves are open, then press reset once.",
   "when_to_call_engineer": "Call a Gas Safe registered engineer if you have to top up more than once every few months, the gauge goes above about 2.5 bar when hot, water drips from the outside overflow pipe, or the code returns after topping up.",
   "engineer_after_one_reset": true,
   "page_url": "https://combicert.co.uk/boiler-fault-codes/baxi/#baxi-h0042",
   "source_manual": "Baxi 600 Combi 2 Installation and Service Manual & Boiler Fiche",
   "source_doc": "7796561-03 (04/23)",
   "source_pages": "pp. 73–77, section 11.2 Error codes (Tab. 33 and Tab. 34)",
   "source_url": "https://edge.sitecorecloud.io/bdrthermea1-platform-production-864a/media/Project/BaxiUK/BaxiUK/Files/Product-Literature/Boilers/Combi-boilers/Baxi-600-Combi-2/baxi-600-combi-2-installation-manual.pdf",
   "source_type": "manufacturer"
  },
  {
   "id": "baxi-h0105",
   "code": "H.01.05",
   "brand": "Baxi",
   "model_range": "Baxi 600 Combi 2 (24 / 30 / 36)",
   "category": "Water pressure / circulation",
   "meaning": "The temperature difference between flow and return has reached its maximum.",
   "homeowner_action": "There is no homeowner check that fixes this code. Write down the full code, press reset once, and if it comes back leave the boiler off.",
   "when_to_call_engineer": "Call a Gas Safe registered engineer if you have to top up more than once every few months, the gauge goes above about 2.5 bar when hot, water drips from the outside overflow pipe, or the code returns after topping up.",
   "engineer_after_one_reset": true,
   "page_url": "https://combicert.co.uk/boiler-fault-codes/baxi/#baxi-h0105",
   "source_manual": "Baxi 600 Combi 2 Installation and Service Manual & Boiler Fiche",
   "source_doc": "7796561-03 (04/23)",
   "source_pages": "pp. 73–77, section 11.2 Error codes (Tab. 33 and Tab. 34)",
   "source_url": "https://edge.sitecorecloud.io/bdrthermea1-platform-production-864a/media/Project/BaxiUK/BaxiUK/Files/Product-Literature/Boilers/Combi-boilers/Baxi-600-Combi-2/baxi-600-combi-2-installation-manual.pdf",
   "source_type": "manufacturer"
  },
  {
   "id": "baxi-h0118",
   "code": "H.01.18",
   "brand": "Baxi",
   "model_range": "Baxi 600 Combi 2 (24 / 30 / 36)",
   "category": "Water pressure / circulation",
   "meaning": "No water circulation was detected (temporary).",
   "homeowner_action": "There is no homeowner check that fixes this code. Write down the full code, press reset once, and if it comes back leave the boiler off.",
   "when_to_call_engineer": "Call a Gas Safe registered engineer if you have to top up more than once every few months, the gauge goes above about 2.5 bar when hot, water drips from the outside overflow pipe, or the code returns after topping up.",
   "engineer_after_one_reset": true,
   "page_url": "https://combicert.co.uk/boiler-fault-codes/baxi/#baxi-h0118",
   "source_manual": "Baxi 600 Combi 2 Installation and Service Manual & Boiler Fiche",
   "source_doc": "7796561-03 (04/23)",
   "source_pages": "pp. 73–77, section 11.2 Error codes (Tab. 33 and Tab. 34)",
   "source_url": "https://edge.sitecorecloud.io/bdrthermea1-platform-production-864a/media/Project/BaxiUK/BaxiUK/Files/Product-Literature/Boilers/Combi-boilers/Baxi-600-Combi-2/baxi-600-combi-2-installation-manual.pdf",
   "source_type": "manufacturer"
  },
  {
   "id": "baxi-h0207",
   "code": "H.02.07",
   "brand": "Baxi",
   "model_range": "Baxi 600 Combi 2 (24 / 30 / 36)",
   "category": "Water pressure / circulation",
   "meaning": "Pressure in the heating circuit is low (the boiler stops until it is restored).",
   "homeowner_action": "Look at the pressure gauge while the boiler is cold. If it is below about 1 bar, top it up with the filling loop exactly as your user guide shows, to about 1–1.5 bar or the figure in your guide, then close the loop fully. Check the radiator valves are open, then press reset once.",
   "when_to_call_engineer": "Call a Gas Safe registered engineer if you have to top up more than once every few months, the gauge goes above about 2.5 bar when hot, water drips from the outside overflow pipe, or the code returns after topping up.",
   "engineer_after_one_reset": false,
   "page_url": "https://combicert.co.uk/boiler-fault-codes/baxi/#baxi-h0207",
   "source_manual": "Baxi 600 Combi 2 Installation and Service Manual & Boiler Fiche",
   "source_doc": "7796561-03 (04/23)",
   "source_pages": "pp. 73–77, section 11.2 Error codes (Tab. 33 and Tab. 34)",
   "source_url": "https://edge.sitecorecloud.io/bdrthermea1-platform-production-864a/media/Project/BaxiUK/BaxiUK/Files/Product-Literature/Boilers/Combi-boilers/Baxi-600-Combi-2/baxi-600-combi-2-installation-manual.pdf",
   "source_type": "manufacturer"
  },
  {
   "id": "baxi-e0117",
   "code": "E.01.17",
   "brand": "Baxi",
   "model_range": "Baxi 600 Combi 2 (24 / 30 / 36)",
   "category": "Water pressure / circulation",
   "meaning": "No water circulation (permanent lockout).",
   "homeowner_action": "There is no homeowner check that fixes this code. Write down the full code, press reset once, and if it comes back leave the boiler off.",
   "when_to_call_engineer": "Call a Gas Safe registered engineer if you have to top up more than once every few months, the gauge goes above about 2.5 bar when hot, water drips from the outside overflow pipe, or the code returns after topping up.",
   "engineer_after_one_reset": true,
   "page_url": "https://combicert.co.uk/boiler-fault-codes/baxi/#baxi-e0117",
   "source_manual": "Baxi 600 Combi 2 Installation and Service Manual & Boiler Fiche",
   "source_doc": "7796561-03 (04/23)",
   "source_pages": "pp. 73–77, section 11.2 Error codes (Tab. 33 and Tab. 34)",
   "source_url": "https://edge.sitecorecloud.io/bdrthermea1-platform-production-864a/media/Project/BaxiUK/BaxiUK/Files/Product-Literature/Boilers/Combi-boilers/Baxi-600-Combi-2/baxi-600-combi-2-installation-manual.pdf",
   "source_type": "manufacturer"
  },
  {
   "id": "baxi-h0108",
   "code": "H.01.08",
   "brand": "Baxi",
   "model_range": "Baxi 600 Combi 2 (24 / 30 / 36)",
   "category": "Temperature / overheat",
   "meaning": "The heating flow temperature rose too quickly; the boiler pauses for 10 minutes.",
   "homeowner_action": "Let the boiler cool for 20 to 30 minutes, then press reset once. If the code comes back, leave the boiler off.",
   "when_to_call_engineer": "Call a Gas Safe registered engineer if the code comes back after one reset. Overheat shut-downs are safety devices doing their job, so this is engineer-only.",
   "engineer_after_one_reset": true,
   "page_url": "https://combicert.co.uk/boiler-fault-codes/baxi/#baxi-h0108",
   "source_manual": "Baxi 600 Combi 2 Installation and Service Manual & Boiler Fiche",
   "source_doc": "7796561-03 (04/23)",
   "source_pages": "pp. 73–77, section 11.2 Error codes (Tab. 33 and Tab. 34)",
   "source_url": "https://edge.sitecorecloud.io/bdrthermea1-platform-production-864a/media/Project/BaxiUK/BaxiUK/Files/Product-Literature/Boilers/Combi-boilers/Baxi-600-Combi-2/baxi-600-combi-2-installation-manual.pdf",
   "source_type": "manufacturer"
  },
  {
   "id": "baxi-h0114",
   "code": "H.01.14",
   "brand": "Baxi",
   "model_range": "Baxi 600 Combi 2 (24 / 30 / 36)",
   "category": "Temperature / overheat",
   "meaning": "The maximum flow temperature has been reached.",
   "homeowner_action": "Let the boiler cool for 20 to 30 minutes, then press reset once. If the code comes back, leave the boiler off.",
   "when_to_call_engineer": "Call a Gas Safe registered engineer if the code comes back after one reset. Overheat shut-downs are safety devices doing their job, so this is engineer-only.",
   "engineer_after_one_reset": true,
   "page_url": "https://combicert.co.uk/boiler-fault-codes/baxi/#baxi-h0114",
   "source_manual": "Baxi 600 Combi 2 Installation and Service Manual & Boiler Fiche",
   "source_doc": "7796561-03 (04/23)",
   "source_pages": "pp. 73–77, section 11.2 Error codes (Tab. 33 and Tab. 34)",
   "source_url": "https://edge.sitecorecloud.io/bdrthermea1-platform-production-864a/media/Project/BaxiUK/BaxiUK/Files/Product-Literature/Boilers/Combi-boilers/Baxi-600-Combi-2/baxi-600-combi-2-installation-manual.pdf",
   "source_type": "manufacturer"
  },
  {
   "id": "baxi-h0121",
   "code": "H.01.21",
   "brand": "Baxi",
   "model_range": "Baxi 600 Combi 2 (24 / 30 / 36)",
   "category": "Temperature / overheat",
   "meaning": "The flow temperature rose too quickly in hot water mode; the boiler pauses for 10 minutes.",
   "homeowner_action": "Let the boiler cool for 20 to 30 minutes, then press reset once. If the code comes back, leave the boiler off.",
   "when_to_call_engineer": "Call a Gas Safe registered engineer if the code comes back after one reset. Overheat shut-downs are safety devices doing their job, so this is engineer-only.",
   "engineer_after_one_reset": true,
   "page_url": "https://combicert.co.uk/boiler-fault-codes/baxi/#baxi-h0121",
   "source_manual": "Baxi 600 Combi 2 Installation and Service Manual & Boiler Fiche",
   "source_doc": "7796561-03 (04/23)",
   "source_pages": "pp. 73–77, section 11.2 Error codes (Tab. 33 and Tab. 34)",
   "source_url": "https://edge.sitecorecloud.io/bdrthermea1-platform-production-864a/media/Project/BaxiUK/BaxiUK/Files/Product-Literature/Boilers/Combi-boilers/Baxi-600-Combi-2/baxi-600-combi-2-installation-manual.pdf",
   "source_type": "manufacturer"
  },
  {
   "id": "baxi-e0403",
   "code": "E.04.03",
   "brand": "Baxi",
   "model_range": "Baxi 600 Combi 2 (24 / 30 / 36)",
   "category": "Temperature / overheat",
   "meaning": "The maximum flow temperature has been exceeded.",
   "homeowner_action": "Let the boiler cool for 20 to 30 minutes, then press reset once. If the code comes back, leave the boiler off.",
   "when_to_call_engineer": "Call a Gas Safe registered engineer if the code comes back after one reset. Overheat shut-downs are safety devices doing their job, so this is engineer-only.",
   "engineer_after_one_reset": true,
   "page_url": "https://combicert.co.uk/boiler-fault-codes/baxi/#baxi-e0403",
   "source_manual": "Baxi 600 Combi 2 Installation and Service Manual & Boiler Fiche",
   "source_doc": "7796561-03 (04/23)",
   "source_pages": "pp. 73–77, section 11.2 Error codes (Tab. 33 and Tab. 34)",
   "source_url": "https://edge.sitecorecloud.io/bdrthermea1-platform-production-864a/media/Project/BaxiUK/BaxiUK/Files/Product-Literature/Boilers/Combi-boilers/Baxi-600-Combi-2/baxi-600-combi-2-installation-manual.pdf",
   "source_type": "manufacturer"
  },
  {
   "id": "baxi-e0408",
   "code": "E.04.08",
   "brand": "Baxi",
   "model_range": "Baxi 600 Combi 2 (24 / 30 / 36)",
   "category": "Temperature / overheat",
   "meaning": "The maximum safe temperature has been reached (the safety thermostat has acted).",
   "homeowner_action": "Let the boiler cool for 20 to 30 minutes, then press reset once. If the code comes back, leave the boiler off.",
   "when_to_call_engineer": "Call a Gas Safe registered engineer if the code comes back after one reset. Overheat shut-downs are safety devices doing their job, so this is engineer-only.",
   "engineer_after_one_reset": true,
   "page_url": "https://combicert.co.uk/boiler-fault-codes/baxi/#baxi-e0408",
   "source_manual": "Baxi 600 Combi 2 Installation and Service Manual & Boiler Fiche",
   "source_doc": "7796561-03 (04/23)",
   "source_pages": "pp. 73–77, section 11.2 Error codes (Tab. 33 and Tab. 34)",
   "source_url": "https://edge.sitecorecloud.io/bdrthermea1-platform-production-864a/media/Project/BaxiUK/BaxiUK/Files/Product-Literature/Boilers/Combi-boilers/Baxi-600-Combi-2/baxi-600-combi-2-installation-manual.pdf",
   "source_type": "manufacturer"
  },
  {
   "id": "baxi-e0120",
   "code": "E.01.20",
   "brand": "Baxi",
   "model_range": "Baxi 600 Combi 2 (24 / 30 / 36)",
   "category": "Flue / fan / air",
   "meaning": "The maximum flue gas temperature has been reached.",
   "homeowner_action": "There is no homeowner check that fixes this code. Write down the full code, press reset once, and if it comes back leave the boiler off.",
   "when_to_call_engineer": "Call a Gas Safe registered engineer if the terminal looks clear and the code returns. Flue and fan faults can affect how combustion gases leave your home, so this is engineer-only.",
   "engineer_after_one_reset": true,
   "page_url": "https://combicert.co.uk/boiler-fault-codes/baxi/#baxi-e0120",
   "source_manual": "Baxi 600 Combi 2 Installation and Service Manual & Boiler Fiche",
   "source_doc": "7796561-03 (04/23)",
   "source_pages": "pp. 73–77, section 11.2 Error codes (Tab. 33 and Tab. 34)",
   "source_url": "https://edge.sitecorecloud.io/bdrthermea1-platform-production-864a/media/Project/BaxiUK/BaxiUK/Files/Product-Literature/Boilers/Combi-boilers/Baxi-600-Combi-2/baxi-600-combi-2-installation-manual.pdf",
   "source_type": "manufacturer"
  },
  {
   "id": "baxi-e0413",
   "code": "E.04.13",
   "brand": "Baxi",
   "model_range": "Baxi 600 Combi 2 (24 / 30 / 36)",
   "category": "Flue / fan / air",
   "meaning": "The fan blade is blocked.",
   "homeowner_action": "There is no homeowner check that fixes this code. Write down the full code, press reset once, and if it comes back leave the boiler off.",
   "when_to_call_engineer": "Call a Gas Safe registered engineer if the terminal looks clear and the code returns. Flue and fan faults can affect how combustion gases leave your home, so this is engineer-only.",
   "engineer_after_one_reset": true,
   "page_url": "https://combicert.co.uk/boiler-fault-codes/baxi/#baxi-e0413",
   "source_manual": "Baxi 600 Combi 2 Installation and Service Manual & Boiler Fiche",
   "source_doc": "7796561-03 (04/23)",
   "source_pages": "pp. 73–77, section 11.2 Error codes (Tab. 33 and Tab. 34)",
   "source_url": "https://edge.sitecorecloud.io/bdrthermea1-platform-production-864a/media/Project/BaxiUK/BaxiUK/Files/Product-Literature/Boilers/Combi-boilers/Baxi-600-Combi-2/baxi-600-combi-2-installation-manual.pdf",
   "source_type": "manufacturer"
  },
  {
   "id": "baxi-e0415",
   "code": "E.04.15",
   "brand": "Baxi",
   "model_range": "Baxi 600 Combi 2 (24 / 30 / 36)",
   "category": "Flue / fan / air",
   "meaning": "The flue gas exhaust pipe is blocked.",
   "homeowner_action": "From outside, look at the flue terminal without touching it and make sure nothing is covering it, such as a bag, snow, a nest or stored items. In freezing weather, check the condensate pipe and thaw it with warm (not boiling) water. Press reset once. Do not touch or adjust any flue parts.",
   "when_to_call_engineer": "Call a Gas Safe registered engineer if the terminal looks clear and the code returns. Flue and fan faults can affect how combustion gases leave your home, so this is engineer-only.",
   "engineer_after_one_reset": false,
   "page_url": "https://combicert.co.uk/boiler-fault-codes/baxi/#baxi-e0415",
   "source_manual": "Baxi 600 Combi 2 Installation and Service Manual & Boiler Fiche",
   "source_doc": "7796561-03 (04/23)",
   "source_pages": "pp. 73–77, section 11.2 Error codes (Tab. 33 and Tab. 34)",
   "source_url": "https://edge.sitecorecloud.io/bdrthermea1-platform-production-864a/media/Project/BaxiUK/BaxiUK/Files/Product-Literature/Boilers/Combi-boilers/Baxi-600-Combi-2/baxi-600-combi-2-installation-manual.pdf",
   "source_type": "manufacturer"
  },
  {
   "id": "baxi-a0034",
   "code": "A.00.34",
   "brand": "Baxi",
   "model_range": "Baxi 600 Combi 2 (24 / 30 / 36)",
   "category": "Sensors / thermistors",
   "meaning": "The boiler expects an outdoor sensor but cannot detect one.",
   "homeowner_action": "Nothing urgent: the boiler normally keeps heating without the outdoor sensor, using a fixed setting. Press reset once to see if it clears.",
   "when_to_call_engineer": "Call a Gas Safe registered engineer if the code returns. Testing and replacing sensors means opening the casing, so this is engineer-only.",
   "engineer_after_one_reset": true,
   "page_url": "https://combicert.co.uk/boiler-fault-codes/baxi/#baxi-a0034",
   "source_manual": "Baxi 600 Combi 2 Installation and Service Manual & Boiler Fiche",
   "source_doc": "7796561-03 (04/23)",
   "source_pages": "pp. 73–77, section 11.2 Error codes (Tab. 33 and Tab. 34)",
   "source_url": "https://edge.sitecorecloud.io/bdrthermea1-platform-production-864a/media/Project/BaxiUK/BaxiUK/Files/Product-Literature/Boilers/Combi-boilers/Baxi-600-Combi-2/baxi-600-combi-2-installation-manual.pdf",
   "source_type": "manufacturer"
  },
  {
   "id": "baxi-e0004",
   "code": "E.00.04",
   "brand": "Baxi",
   "model_range": "Baxi 600 Combi 2 (24 / 30 / 36)",
   "category": "Sensors / thermistors",
   "meaning": "The return temperature sensor is disconnected.",
   "homeowner_action": "Write down the full code. Check the boiler has power, then switch it off and on at its mains switch or press reset once. If the code comes back, leave it there: sensors are inside the casing.",
   "when_to_call_engineer": "Call a Gas Safe registered engineer if the code returns. Testing and replacing sensors means opening the casing, so this is engineer-only.",
   "engineer_after_one_reset": true,
   "page_url": "https://combicert.co.uk/boiler-fault-codes/baxi/#baxi-e0004",
   "source_manual": "Baxi 600 Combi 2 Installation and Service Manual & Boiler Fiche",
   "source_doc": "7796561-03 (04/23)",
   "source_pages": "pp. 73–77, section 11.2 Error codes (Tab. 33 and Tab. 34)",
   "source_url": "https://edge.sitecorecloud.io/bdrthermea1-platform-production-864a/media/Project/BaxiUK/BaxiUK/Files/Product-Literature/Boilers/Combi-boilers/Baxi-600-Combi-2/baxi-600-combi-2-installation-manual.pdf",
   "source_type": "manufacturer"
  },
  {
   "id": "baxi-e0005",
   "code": "E.00.05",
   "brand": "Baxi",
   "model_range": "Baxi 600 Combi 2 (24 / 30 / 36)",
   "category": "Sensors / thermistors",
   "meaning": "The return temperature sensor is short circuited.",
   "homeowner_action": "Write down the full code. Check the boiler has power, then switch it off and on at its mains switch or press reset once. If the code comes back, leave it there: sensors are inside the casing.",
   "when_to_call_engineer": "Call a Gas Safe registered engineer if the code returns. Testing and replacing sensors means opening the casing, so this is engineer-only.",
   "engineer_after_one_reset": true,
   "page_url": "https://combicert.co.uk/boiler-fault-codes/baxi/#baxi-e0005",
   "source_manual": "Baxi 600 Combi 2 Installation and Service Manual & Boiler Fiche",
   "source_doc": "7796561-03 (04/23)",
   "source_pages": "pp. 73–77, section 11.2 Error codes (Tab. 33 and Tab. 34)",
   "source_url": "https://edge.sitecorecloud.io/bdrthermea1-platform-production-864a/media/Project/BaxiUK/BaxiUK/Files/Product-Literature/Boilers/Combi-boilers/Baxi-600-Combi-2/baxi-600-combi-2-installation-manual.pdf",
   "source_type": "manufacturer"
  },
  {
   "id": "baxi-e0020",
   "code": "E.00.20",
   "brand": "Baxi",
   "model_range": "Baxi 600 Combi 2 (24 / 30 / 36)",
   "category": "Sensors / thermistors",
   "meaning": "The flue gas temperature sensor is short circuited or reading below range.",
   "homeowner_action": "Write down the full code. Check the boiler has power, then switch it off and on at its mains switch or press reset once. If the code comes back, leave it there: sensors are inside the casing.",
   "when_to_call_engineer": "Call a Gas Safe registered engineer if the code returns. Testing and replacing sensors means opening the casing, so this is engineer-only.",
   "engineer_after_one_reset": true,
   "page_url": "https://combicert.co.uk/boiler-fault-codes/baxi/#baxi-e0020",
   "source_manual": "Baxi 600 Combi 2 Installation and Service Manual & Boiler Fiche",
   "source_doc": "7796561-03 (04/23)",
   "source_pages": "pp. 73–77, section 11.2 Error codes (Tab. 33 and Tab. 34)",
   "source_url": "https://edge.sitecorecloud.io/bdrthermea1-platform-production-864a/media/Project/BaxiUK/BaxiUK/Files/Product-Literature/Boilers/Combi-boilers/Baxi-600-Combi-2/baxi-600-combi-2-installation-manual.pdf",
   "source_type": "manufacturer"
  },
  {
   "id": "baxi-e0021",
   "code": "E.00.21",
   "brand": "Baxi",
   "model_range": "Baxi 600 Combi 2 (24 / 30 / 36)",
   "category": "Sensors / thermistors",
   "meaning": "The flue gas temperature sensor is reading above range.",
   "homeowner_action": "Write down the full code. Check the boiler has power, then switch it off and on at its mains switch or press reset once. If the code comes back, leave it there: sensors are inside the casing.",
   "when_to_call_engineer": "Call a Gas Safe registered engineer if the code returns. Testing and replacing sensors means opening the casing, so this is engineer-only.",
   "engineer_after_one_reset": true,
   "page_url": "https://combicert.co.uk/boiler-fault-codes/baxi/#baxi-e0021",
   "source_manual": "Baxi 600 Combi 2 Installation and Service Manual & Boiler Fiche",
   "source_doc": "7796561-03 (04/23)",
   "source_pages": "pp. 73–77, section 11.2 Error codes (Tab. 33 and Tab. 34)",
   "source_url": "https://edge.sitecorecloud.io/bdrthermea1-platform-production-864a/media/Project/BaxiUK/BaxiUK/Files/Product-Literature/Boilers/Combi-boilers/Baxi-600-Combi-2/baxi-600-combi-2-installation-manual.pdf",
   "source_type": "manufacturer"
  },
  {
   "id": "baxi-e0112",
   "code": "E.01.12",
   "brand": "Baxi",
   "model_range": "Baxi 600 Combi 2 (24 / 30 / 36)",
   "category": "Sensors / thermistors",
   "meaning": "The return sensor is reading hotter than the flow sensor.",
   "homeowner_action": "Write down the full code. Check the boiler has power, then switch it off and on at its mains switch or press reset once. If the code comes back, leave it there: sensors are inside the casing.",
   "when_to_call_engineer": "Call a Gas Safe registered engineer if the code returns. Testing and replacing sensors means opening the casing, so this is engineer-only.",
   "engineer_after_one_reset": true,
   "page_url": "https://combicert.co.uk/boiler-fault-codes/baxi/#baxi-e0112",
   "source_manual": "Baxi 600 Combi 2 Installation and Service Manual & Boiler Fiche",
   "source_doc": "7796561-03 (04/23)",
   "source_pages": "pp. 73–77, section 11.2 Error codes (Tab. 33 and Tab. 34)",
   "source_url": "https://edge.sitecorecloud.io/bdrthermea1-platform-production-864a/media/Project/BaxiUK/BaxiUK/Files/Product-Literature/Boilers/Combi-boilers/Baxi-600-Combi-2/baxi-600-combi-2-installation-manual.pdf",
   "source_type": "manufacturer"
  },
  {
   "id": "baxi-e0401",
   "code": "E.04.01",
   "brand": "Baxi",
   "model_range": "Baxi 600 Combi 2 (24 / 30 / 36)",
   "category": "Sensors / thermistors",
   "meaning": "The flow temperature sensor is short circuited.",
   "homeowner_action": "Write down the full code. Check the boiler has power, then switch it off and on at its mains switch or press reset once. If the code comes back, leave it there: sensors are inside the casing.",
   "when_to_call_engineer": "Call a Gas Safe registered engineer if the code returns. Testing and replacing sensors means opening the casing, so this is engineer-only.",
   "engineer_after_one_reset": true,
   "page_url": "https://combicert.co.uk/boiler-fault-codes/baxi/#baxi-e0401",
   "source_manual": "Baxi 600 Combi 2 Installation and Service Manual & Boiler Fiche",
   "source_doc": "7796561-03 (04/23)",
   "source_pages": "pp. 73–77, section 11.2 Error codes (Tab. 33 and Tab. 34)",
   "source_url": "https://edge.sitecorecloud.io/bdrthermea1-platform-production-864a/media/Project/BaxiUK/BaxiUK/Files/Product-Literature/Boilers/Combi-boilers/Baxi-600-Combi-2/baxi-600-combi-2-installation-manual.pdf",
   "source_type": "manufacturer"
  },
  {
   "id": "baxi-e0402",
   "code": "E.04.02",
   "brand": "Baxi",
   "model_range": "Baxi 600 Combi 2 (24 / 30 / 36)",
   "category": "Sensors / thermistors",
   "meaning": "The flow temperature sensor is disconnected.",
   "homeowner_action": "Write down the full code. Check the boiler has power, then switch it off and on at its mains switch or press reset once. If the code comes back, leave it there: sensors are inside the casing.",
   "when_to_call_engineer": "Call a Gas Safe registered engineer if the code returns. Testing and replacing sensors means opening the casing, so this is engineer-only.",
   "engineer_after_one_reset": true,
   "page_url": "https://combicert.co.uk/boiler-fault-codes/baxi/#baxi-e0402",
   "source_manual": "Baxi 600 Combi 2 Installation and Service Manual & Boiler Fiche",
   "source_doc": "7796561-03 (04/23)",
   "source_pages": "pp. 73–77, section 11.2 Error codes (Tab. 33 and Tab. 34)",
   "source_url": "https://edge.sitecorecloud.io/bdrthermea1-platform-production-864a/media/Project/BaxiUK/BaxiUK/Files/Product-Literature/Boilers/Combi-boilers/Baxi-600-Combi-2/baxi-600-combi-2-installation-manual.pdf",
   "source_type": "manufacturer"
  },
  {
   "id": "baxi-h0305",
   "code": "H.03.05",
   "brand": "Baxi",
   "model_range": "Baxi 600 Combi 2 (24 / 30 / 36)",
   "category": "PCB / electrical",
   "meaning": "The power supply voltage is too low.",
   "homeowner_action": "Check whether lights are dimming or other appliances are struggling. If they are, contact an electrician or your electricity network operator (call 105 for a power cut). Then press reset once.",
   "when_to_call_engineer": "Call a Gas Safe registered engineer if your mains supply is fine and the code continues, so the boiler's own supply and board can be checked.",
   "engineer_after_one_reset": false,
   "page_url": "https://combicert.co.uk/boiler-fault-codes/baxi/#baxi-h0305",
   "source_manual": "Baxi 600 Combi 2 Installation and Service Manual & Boiler Fiche",
   "source_doc": "7796561-03 (04/23)",
   "source_pages": "pp. 73–77, section 11.2 Error codes (Tab. 33 and Tab. 34)",
   "source_url": "https://edge.sitecorecloud.io/bdrthermea1-platform-production-864a/media/Project/BaxiUK/BaxiUK/Files/Product-Literature/Boilers/Combi-boilers/Baxi-600-Combi-2/baxi-600-combi-2-installation-manual.pdf",
   "source_type": "manufacturer"
  },
  {
   "id": "baxi-e0217",
   "code": "E.02.17",
   "brand": "Baxi",
   "model_range": "Baxi 600 Combi 2 (24 / 30 / 36)",
   "category": "PCB / electrical",
   "meaning": "Permanent communication failure between the gas valve and the main board.",
   "homeowner_action": "Write down the full code. Check the boiler has power and nothing else in the house has tripped, then switch the boiler off and on at its mains switch or press reset once. If the code comes back, leave the boiler off.",
   "when_to_call_engineer": "Call a Gas Safe registered engineer if the code returns. Board, wiring and gas valve checks mean opening the casing, so this is engineer-only.",
   "engineer_after_one_reset": true,
   "page_url": "https://combicert.co.uk/boiler-fault-codes/baxi/#baxi-e0217",
   "source_manual": "Baxi 600 Combi 2 Installation and Service Manual & Boiler Fiche",
   "source_doc": "7796561-03 (04/23)",
   "source_pages": "pp. 73–77, section 11.2 Error codes (Tab. 33 and Tab. 34)",
   "source_url": "https://edge.sitecorecloud.io/bdrthermea1-platform-production-864a/media/Project/BaxiUK/BaxiUK/Files/Product-Literature/Boilers/Combi-boilers/Baxi-600-Combi-2/baxi-600-combi-2-installation-manual.pdf",
   "source_type": "manufacturer"
  },
  {
   "id": "baxi-h0209",
   "code": "H.02.09",
   "brand": "Baxi",
   "model_range": "Baxi 600 Combi 2 (24 / 30 / 36)",
   "category": "Other / controls",
   "meaning": "A blocking input or frost protection is active, so the boiler is partly stopped.",
   "homeowner_action": "Check any external timer, thermostat or frost control connected to the boiler is on. The code clears itself when the input is released.",
   "when_to_call_engineer": "Call a Gas Safe registered engineer if the code stays after you have checked the controls, or keeps coming back.",
   "engineer_after_one_reset": false,
   "page_url": "https://combicert.co.uk/boiler-fault-codes/baxi/#baxi-h0209",
   "source_manual": "Baxi 600 Combi 2 Installation and Service Manual & Boiler Fiche",
   "source_doc": "7796561-03 (04/23)",
   "source_pages": "pp. 73–77, section 11.2 Error codes (Tab. 33 and Tab. 34)",
   "source_url": "https://edge.sitecorecloud.io/bdrthermea1-platform-production-864a/media/Project/BaxiUK/BaxiUK/Files/Product-Literature/Boilers/Combi-boilers/Baxi-600-Combi-2/baxi-600-combi-2-installation-manual.pdf",
   "source_type": "manufacturer"
  },
  {
   "id": "baxi-h0210",
   "code": "H.02.10",
   "brand": "Baxi",
   "model_range": "Baxi 600 Combi 2 (24 / 30 / 36)",
   "category": "Other / controls",
   "meaning": "A blocking input signal has stopped the boiler completely.",
   "homeowner_action": "Check any external timer, thermostat or control connected to the boiler is on. The code clears itself when the input is released.",
   "when_to_call_engineer": "Call a Gas Safe registered engineer if the code stays after you have checked the controls, or keeps coming back.",
   "engineer_after_one_reset": false,
   "page_url": "https://combicert.co.uk/boiler-fault-codes/baxi/#baxi-h0210",
   "source_manual": "Baxi 600 Combi 2 Installation and Service Manual & Boiler Fiche",
   "source_doc": "7796561-03 (04/23)",
   "source_pages": "pp. 73–77, section 11.2 Error codes (Tab. 33 and Tab. 34)",
   "source_url": "https://edge.sitecorecloud.io/bdrthermea1-platform-production-864a/media/Project/BaxiUK/BaxiUK/Files/Product-Literature/Boilers/Combi-boilers/Baxi-600-Combi-2/baxi-600-combi-2-installation-manual.pdf",
   "source_type": "manufacturer"
  },
  {
   "id": "baxi-e09",
   "code": "E09",
   "brand": "Baxi",
   "model_range": "Baxi 600 Combi (624 / 630, first generation)",
   "category": "Ignition / flame",
   "meaning": "Gas valve connection cable fault.",
   "homeowner_action": "There is no homeowner check that fixes this code. Write down the full code, press reset once, and if it comes back leave the boiler off.",
   "when_to_call_engineer": "Call a Gas Safe registered engineer if the code comes back after one reset. Ignition and flame faults involve gas, so this is engineer-only.",
   "engineer_after_one_reset": true,
   "page_url": "https://combicert.co.uk/boiler-fault-codes/baxi/#baxi-e09",
   "source_manual": "Baxi Combi 624–630 Installation and Service Manual",
   "source_doc": "7679306-1 (10/08/2017)",
   "source_pages": "p. 64, section 10.1 Error codes (Fig. 69)",
   "source_url": "https://www.freeboilermanuals.com/assets/pdf/baxi/baxi_600_combi_installation_and_service_manual.pdf",
   "source_type": "trade-site mirror (no manufacturer-hosted copy found)"
  },
  {
   "id": "baxi-e15",
   "code": "E15",
   "brand": "Baxi",
   "model_range": "Baxi 600 Combi (624 / 630, first generation)",
   "category": "Ignition / flame",
   "meaning": "Gas valve fault.",
   "homeowner_action": "There is no homeowner check that fixes this code. Write down the full code, press reset once, and if it comes back leave the boiler off.",
   "when_to_call_engineer": "Call a Gas Safe registered engineer if the code comes back after one reset. Ignition and flame faults involve gas, so this is engineer-only.",
   "engineer_after_one_reset": true,
   "page_url": "https://combicert.co.uk/boiler-fault-codes/baxi/#baxi-e15",
   "source_manual": "Baxi Combi 624–630 Installation and Service Manual",
   "source_doc": "7679306-1 (10/08/2017)",
   "source_pages": "p. 64, section 10.1 Error codes (Fig. 69)",
   "source_url": "https://www.freeboilermanuals.com/assets/pdf/baxi/baxi_600_combi_installation_and_service_manual.pdf",
   "source_type": "trade-site mirror (no manufacturer-hosted copy found)"
  },
  {
   "id": "baxi-e128",
   "code": "E128",
   "brand": "Baxi",
   "model_range": "Baxi 600 Combi (624 / 630, first generation)",
   "category": "Ignition / flame",
   "meaning": "Flame failure during normal operation.",
   "homeowner_action": "Check another gas appliance such as the hob works, the gas meter valve is on and, on a prepayment meter, there is credit. In freezing weather, check the plastic condensate pipe outside: if it is frozen, pour warm (not boiling) water along it. Then press reset once. If the code comes back, stop resetting.",
   "when_to_call_engineer": "Call a Gas Safe registered engineer if the gas supply is fine and the code returns after one reset. Ignition and flame faults involve gas, so this is engineer-only.",
   "engineer_after_one_reset": false,
   "page_url": "https://combicert.co.uk/boiler-fault-codes/baxi/#baxi-e128",
   "source_manual": "Baxi Combi 624–630 Installation and Service Manual",
   "source_doc": "7679306-1 (10/08/2017)",
   "source_pages": "p. 64, section 10.1 Error codes (Fig. 69)",
   "source_url": "https://www.freeboilermanuals.com/assets/pdf/baxi/baxi_600_combi_installation_and_service_manual.pdf",
   "source_type": "trade-site mirror (no manufacturer-hosted copy found)"
  },
  {
   "id": "baxi-e133",
   "code": "E133",
   "brand": "Baxi",
   "model_range": "Baxi 600 Combi (624 / 630, first generation)",
   "category": "Ignition / flame",
   "meaning": "Interruption of the gas supply or flame failure: the boiler could not light or prove a flame.",
   "homeowner_action": "Check another gas appliance such as the hob works, the gas meter valve is on and, on a prepayment meter, there is credit. In freezing weather, check the plastic condensate pipe outside: if it is frozen, pour warm (not boiling) water along it. Then press reset once. If the code comes back, stop resetting.",
   "when_to_call_engineer": "Call a Gas Safe registered engineer if the gas supply is fine and the code returns after one reset. Ignition and flame faults involve gas, so this is engineer-only.",
   "engineer_after_one_reset": false,
   "page_url": "https://combicert.co.uk/boiler-fault-codes/baxi/#baxi-e133",
   "source_manual": "Baxi Combi 624–630 Installation and Service Manual",
   "source_doc": "7679306-1 (10/08/2017)",
   "source_pages": "p. 64, section 10.1 Error codes (Fig. 69)",
   "source_url": "https://www.freeboilermanuals.com/assets/pdf/baxi/baxi_600_combi_installation_and_service_manual.pdf",
   "source_type": "trade-site mirror (no manufacturer-hosted copy found)"
  },
  {
   "id": "baxi-e135",
   "code": "E135",
   "brand": "Baxi",
   "model_range": "Baxi 600 Combi (624 / 630, first generation)",
   "category": "Ignition / flame",
   "meaning": "Interruption of the gas supply, listed in the manual as an internal error.",
   "homeowner_action": "Check another gas appliance such as the hob works, the gas meter valve is on and, on a prepayment meter, there is credit. In freezing weather, check the plastic condensate pipe outside: if it is frozen, pour warm (not boiling) water along it. Then press reset once. If the code comes back, stop resetting.",
   "when_to_call_engineer": "Call a Gas Safe registered engineer if the gas supply is fine and the code returns after one reset. Ignition and flame faults involve gas, so this is engineer-only.",
   "engineer_after_one_reset": false,
   "page_url": "https://combicert.co.uk/boiler-fault-codes/baxi/#baxi-e135",
   "source_manual": "Baxi Combi 624–630 Installation and Service Manual",
   "source_doc": "7679306-1 (10/08/2017)",
   "source_pages": "p. 64, section 10.1 Error codes (Fig. 69)",
   "source_url": "https://www.freeboilermanuals.com/assets/pdf/baxi/baxi_600_combi_installation_and_service_manual.pdf",
   "source_type": "trade-site mirror (no manufacturer-hosted copy found)"
  },
  {
   "id": "baxi-e384",
   "code": "E384",
   "brand": "Baxi",
   "model_range": "Baxi 600 Combi (624 / 630, first generation)",
   "category": "Ignition / flame",
   "meaning": "False flame: a flame signal is detected when there should be none.",
   "homeowner_action": "There is no homeowner check that fixes this code. Write down the full code, press reset once, and if it comes back leave the boiler off.",
   "when_to_call_engineer": "Call a Gas Safe registered engineer if the code comes back after one reset. Ignition and flame faults involve gas, so this is engineer-only.",
   "engineer_after_one_reset": true,
   "page_url": "https://combicert.co.uk/boiler-fault-codes/baxi/#baxi-e384",
   "source_manual": "Baxi Combi 624–630 Installation and Service Manual",
   "source_doc": "7679306-1 (10/08/2017)",
   "source_pages": "p. 64, section 10.1 Error codes (Fig. 69)",
   "source_url": "https://www.freeboilermanuals.com/assets/pdf/baxi/baxi_600_combi_installation_and_service_manual.pdf",
   "source_type": "trade-site mirror (no manufacturer-hosted copy found)"
  },
  {
   "id": "baxi-e109",
   "code": "E109",
   "brand": "Baxi",
   "model_range": "Baxi 600 Combi (624 / 630, first generation)",
   "category": "Water pressure / circulation",
   "meaning": "Pre-circulation fault: the boiler did not see water circulating before lighting.",
   "homeowner_action": "There is no homeowner check that fixes this code. Write down the full code, press reset once, and if it comes back leave the boiler off.",
   "when_to_call_engineer": "Call a Gas Safe registered engineer if you have to top up more than once every few months, the gauge goes above about 2.5 bar when hot, water drips from the outside overflow pipe, or the code returns after topping up.",
   "engineer_after_one_reset": true,
   "page_url": "https://combicert.co.uk/boiler-fault-codes/baxi/#baxi-e109",
   "source_manual": "Baxi Combi 624–630 Installation and Service Manual",
   "source_doc": "7679306-1 (10/08/2017)",
   "source_pages": "p. 64, section 10.1 Error codes (Fig. 69)",
   "source_url": "https://www.freeboilermanuals.com/assets/pdf/baxi/baxi_600_combi_installation_and_service_manual.pdf",
   "source_type": "trade-site mirror (no manufacturer-hosted copy found)"
  },
  {
   "id": "baxi-e118",
   "code": "E118",
   "brand": "Baxi",
   "model_range": "Baxi 600 Combi (624 / 630, first generation)",
   "category": "Water pressure / circulation",
   "meaning": "Primary system water pressure is too low (the manual says below 0.5 bar).",
   "homeowner_action": "Look at the pressure gauge while the boiler is cold. If it is below about 1 bar, top it up with the filling loop exactly as your user guide shows, to about 1–1.5 bar or the figure in your guide, then close the loop fully. Check the radiator valves are open, then press reset once.",
   "when_to_call_engineer": "Call a Gas Safe registered engineer if you have to top up more than once every few months, the gauge goes above about 2.5 bar when hot, water drips from the outside overflow pipe, or the code returns after topping up.",
   "engineer_after_one_reset": false,
   "page_url": "https://combicert.co.uk/boiler-fault-codes/baxi/#baxi-e118",
   "source_manual": "Baxi Combi 624–630 Installation and Service Manual",
   "source_doc": "7679306-1 (10/08/2017)",
   "source_pages": "p. 64, section 10.1 Error codes (Fig. 69)",
   "source_url": "https://www.freeboilermanuals.com/assets/pdf/baxi/baxi_600_combi_installation_and_service_manual.pdf",
   "source_type": "trade-site mirror (no manufacturer-hosted copy found)"
  },
  {
   "id": "baxi-e125",
   "code": "E125",
   "brand": "Baxi",
   "model_range": "Baxi 600 Combi (624 / 630, first generation)",
   "category": "Water pressure / circulation",
   "meaning": "Circulation fault in the primary circuit. The manual says it shows if the water temperature hardly changes 15 to 30 seconds after lighting, or overshoots the set temperature by 30 °C twice within 10 minutes.",
   "homeowner_action": "There is no homeowner check that fixes this code. Write down the full code, press reset once, and if it comes back leave the boiler off.",
   "when_to_call_engineer": "Call a Gas Safe registered engineer if you have to top up more than once every few months, the gauge goes above about 2.5 bar when hot, water drips from the outside overflow pipe, or the code returns after topping up.",
   "engineer_after_one_reset": true,
   "page_url": "https://combicert.co.uk/boiler-fault-codes/baxi/#baxi-e125",
   "source_manual": "Baxi Combi 624–630 Installation and Service Manual",
   "source_doc": "7679306-1 (10/08/2017)",
   "source_pages": "p. 64, section 10.1 Error codes (Fig. 69)",
   "source_url": "https://www.freeboilermanuals.com/assets/pdf/baxi/baxi_600_combi_installation_and_service_manual.pdf",
   "source_type": "trade-site mirror (no manufacturer-hosted copy found)"
  },
  {
   "id": "baxi-e270",
   "code": "E270",
   "brand": "Baxi",
   "model_range": "Baxi 600 Combi (624 / 630, first generation)",
   "category": "Water pressure / circulation",
   "meaning": "Circulation fault (dry fire): the boiler detected it was firing without enough water flow.",
   "homeowner_action": "There is no homeowner check that fixes this code. Write down the full code, press reset once, and if it comes back leave the boiler off.",
   "when_to_call_engineer": "Call a Gas Safe registered engineer if you have to top up more than once every few months, the gauge goes above about 2.5 bar when hot, water drips from the outside overflow pipe, or the code returns after topping up.",
   "engineer_after_one_reset": true,
   "page_url": "https://combicert.co.uk/boiler-fault-codes/baxi/#baxi-e270",
   "source_manual": "Baxi Combi 624–630 Installation and Service Manual",
   "source_doc": "7679306-1 (10/08/2017)",
   "source_pages": "p. 64, section 10.1 Error codes (Fig. 69)",
   "source_url": "https://www.freeboilermanuals.com/assets/pdf/baxi/baxi_600_combi_installation_and_service_manual.pdf",
   "source_type": "trade-site mirror (no manufacturer-hosted copy found)"
  },
  {
   "id": "baxi-e110",
   "code": "E110",
   "brand": "Baxi",
   "model_range": "Baxi 600 Combi (624 / 630, first generation)",
   "category": "Temperature / overheat",
   "meaning": "The safety (overheat) thermostat has operated: the primary water overheated.",
   "homeowner_action": "Let the boiler cool for 20 to 30 minutes, then press reset once. If the code comes back, leave the boiler off.",
   "when_to_call_engineer": "Call a Gas Safe registered engineer if the code comes back after one reset. Overheat shut-downs are safety devices doing their job, so this is engineer-only.",
   "engineer_after_one_reset": true,
   "page_url": "https://combicert.co.uk/boiler-fault-codes/baxi/#baxi-e110",
   "source_manual": "Baxi Combi 624–630 Installation and Service Manual",
   "source_doc": "7679306-1 (10/08/2017)",
   "source_pages": "p. 64, section 10.1 Error codes (Fig. 69)",
   "source_url": "https://www.freeboilermanuals.com/assets/pdf/baxi/baxi_600_combi_installation_and_service_manual.pdf",
   "source_type": "trade-site mirror (no manufacturer-hosted copy found)"
  },
  {
   "id": "baxi-e130",
   "code": "E130",
   "brand": "Baxi",
   "model_range": "Baxi 600 Combi (624 / 630, first generation)",
   "category": "Flue / fan / air",
   "meaning": "The flue NTC has operated (flue overheat).",
   "homeowner_action": "There is no homeowner check that fixes this code. Write down the full code, press reset once, and if it comes back leave the boiler off.",
   "when_to_call_engineer": "Call a Gas Safe registered engineer if the terminal looks clear and the code returns. Flue and fan faults can affect how combustion gases leave your home, so this is engineer-only.",
   "engineer_after_one_reset": true,
   "page_url": "https://combicert.co.uk/boiler-fault-codes/baxi/#baxi-e130",
   "source_manual": "Baxi Combi 624–630 Installation and Service Manual",
   "source_doc": "7679306-1 (10/08/2017)",
   "source_pages": "p. 64, section 10.1 Error codes (Fig. 69)",
   "source_url": "https://www.freeboilermanuals.com/assets/pdf/baxi/baxi_600_combi_installation_and_service_manual.pdf",
   "source_type": "trade-site mirror (no manufacturer-hosted copy found)"
  },
  {
   "id": "baxi-e160",
   "code": "E160",
   "brand": "Baxi",
   "model_range": "Baxi 600 Combi (624 / 630, first generation)",
   "category": "Flue / fan / air",
   "meaning": "Fan or fan wiring fault.",
   "homeowner_action": "There is no homeowner check that fixes this code. Write down the full code, press reset once, and if it comes back leave the boiler off.",
   "when_to_call_engineer": "Call a Gas Safe registered engineer if the terminal looks clear and the code returns. Flue and fan faults can affect how combustion gases leave your home, so this is engineer-only.",
   "engineer_after_one_reset": true,
   "page_url": "https://combicert.co.uk/boiler-fault-codes/baxi/#baxi-e160",
   "source_manual": "Baxi Combi 624–630 Installation and Service Manual",
   "source_doc": "7679306-1 (10/08/2017)",
   "source_pages": "p. 64, section 10.1 Error codes (Fig. 69)",
   "source_url": "https://www.freeboilermanuals.com/assets/pdf/baxi/baxi_600_combi_installation_and_service_manual.pdf",
   "source_type": "trade-site mirror (no manufacturer-hosted copy found)"
  },
  {
   "id": "baxi-e20",
   "code": "E20",
   "brand": "Baxi",
   "model_range": "Baxi 600 Combi (624 / 630, first generation)",
   "category": "Sensors / thermistors",
   "meaning": "Central heating (flow) NTC sensor fault.",
   "homeowner_action": "Write down the full code. Check the boiler has power, then switch it off and on at its mains switch or press reset once. If the code comes back, leave it there: sensors are inside the casing.",
   "when_to_call_engineer": "Call a Gas Safe registered engineer if the code returns. Testing and replacing sensors means opening the casing, so this is engineer-only.",
   "engineer_after_one_reset": true,
   "page_url": "https://combicert.co.uk/boiler-fault-codes/baxi/#baxi-e20",
   "source_manual": "Baxi Combi 624–630 Installation and Service Manual",
   "source_doc": "7679306-1 (10/08/2017)",
   "source_pages": "p. 64, section 10.1 Error codes (Fig. 69)",
   "source_url": "https://www.freeboilermanuals.com/assets/pdf/baxi/baxi_600_combi_installation_and_service_manual.pdf",
   "source_type": "trade-site mirror (no manufacturer-hosted copy found)"
  },
  {
   "id": "baxi-e28",
   "code": "E28",
   "brand": "Baxi",
   "model_range": "Baxi 600 Combi (624 / 630, first generation)",
   "category": "Sensors / thermistors",
   "meaning": "Flue NTC sensor fault.",
   "homeowner_action": "Write down the full code. Check the boiler has power, then switch it off and on at its mains switch or press reset once. If the code comes back, leave it there: sensors are inside the casing.",
   "when_to_call_engineer": "Call a Gas Safe registered engineer if the code returns. Testing and replacing sensors means opening the casing, so this is engineer-only.",
   "engineer_after_one_reset": true,
   "page_url": "https://combicert.co.uk/boiler-fault-codes/baxi/#baxi-e28",
   "source_manual": "Baxi Combi 624–630 Installation and Service Manual",
   "source_doc": "7679306-1 (10/08/2017)",
   "source_pages": "p. 64, section 10.1 Error codes (Fig. 69)",
   "source_url": "https://www.freeboilermanuals.com/assets/pdf/baxi/baxi_600_combi_installation_and_service_manual.pdf",
   "source_type": "trade-site mirror (no manufacturer-hosted copy found)"
  },
  {
   "id": "baxi-e40",
   "code": "E40",
   "brand": "Baxi",
   "model_range": "Baxi 600 Combi (624 / 630, first generation)",
   "category": "Sensors / thermistors",
   "meaning": "Central heating return NTC sensor fault.",
   "homeowner_action": "Write down the full code. Check the boiler has power, then switch it off and on at its mains switch or press reset once. If the code comes back, leave it there: sensors are inside the casing.",
   "when_to_call_engineer": "Call a Gas Safe registered engineer if the code returns. Testing and replacing sensors means opening the casing, so this is engineer-only.",
   "engineer_after_one_reset": true,
   "page_url": "https://combicert.co.uk/boiler-fault-codes/baxi/#baxi-e40",
   "source_manual": "Baxi Combi 624–630 Installation and Service Manual",
   "source_doc": "7679306-1 (10/08/2017)",
   "source_pages": "p. 64, section 10.1 Error codes (Fig. 69)",
   "source_url": "https://www.freeboilermanuals.com/assets/pdf/baxi/baxi_600_combi_installation_and_service_manual.pdf",
   "source_type": "trade-site mirror (no manufacturer-hosted copy found)"
  },
  {
   "id": "baxi-e154",
   "code": "E154",
   "brand": "Baxi",
   "model_range": "Baxi 600 Combi (624 / 630, first generation)",
   "category": "Sensors / thermistors",
   "meaning": "Flow/return sensor temperature test fault.",
   "homeowner_action": "Write down the full code. Check the boiler has power, then switch it off and on at its mains switch or press reset once. If the code comes back, leave it there: sensors are inside the casing.",
   "when_to_call_engineer": "Call a Gas Safe registered engineer if the code returns. Testing and replacing sensors means opening the casing, so this is engineer-only.",
   "engineer_after_one_reset": true,
   "page_url": "https://combicert.co.uk/boiler-fault-codes/baxi/#baxi-e154",
   "source_manual": "Baxi Combi 624–630 Installation and Service Manual",
   "source_doc": "7679306-1 (10/08/2017)",
   "source_pages": "p. 64, section 10.1 Error codes (Fig. 69)",
   "source_url": "https://www.freeboilermanuals.com/assets/pdf/baxi/baxi_600_combi_installation_and_service_manual.pdf",
   "source_type": "trade-site mirror (no manufacturer-hosted copy found)"
  },
  {
   "id": "baxi-e321",
   "code": "E321",
   "brand": "Baxi",
   "model_range": "Baxi 600 Combi (624 / 630, first generation)",
   "category": "Sensors / thermistors",
   "meaning": "Hot water NTC sensor fault.",
   "homeowner_action": "Write down the full code. Check the boiler has power, then switch it off and on at its mains switch or press reset once. If the code comes back, leave it there: sensors are inside the casing.",
   "when_to_call_engineer": "Call a Gas Safe registered engineer if the code returns. Testing and replacing sensors means opening the casing, so this is engineer-only.",
   "engineer_after_one_reset": true,
   "page_url": "https://combicert.co.uk/boiler-fault-codes/baxi/#baxi-e321",
   "source_manual": "Baxi Combi 624–630 Installation and Service Manual",
   "source_doc": "7679306-1 (10/08/2017)",
   "source_pages": "p. 64, section 10.1 Error codes (Fig. 69)",
   "source_url": "https://www.freeboilermanuals.com/assets/pdf/baxi/baxi_600_combi_installation_and_service_manual.pdf",
   "source_type": "trade-site mirror (no manufacturer-hosted copy found)"
  },
  {
   "id": "baxi-e83",
   "code": "E83",
   "brand": "Baxi",
   "model_range": "Baxi 600 Combi (624 / 630, first generation)",
   "category": "Other / controls",
   "meaning": "Communication error.",
   "homeowner_action": "There is no homeowner check that fixes this code. Write down the full code, press reset once, and if it comes back leave the boiler off.",
   "when_to_call_engineer": "Call a Gas Safe registered engineer if the code stays after you have checked the controls, or keeps coming back.",
   "engineer_after_one_reset": true,
   "page_url": "https://combicert.co.uk/boiler-fault-codes/baxi/#baxi-e83",
   "source_manual": "Baxi Combi 624–630 Installation and Service Manual",
   "source_doc": "7679306-1 (10/08/2017)",
   "source_pages": "p. 64, section 10.1 Error codes (Fig. 69)",
   "source_url": "https://www.freeboilermanuals.com/assets/pdf/baxi/baxi_600_combi_installation_and_service_manual.pdf",
   "source_type": "trade-site mirror (no manufacturer-hosted copy found)"
  },
  {
   "id": "ideal-logic-max-f2",
   "code": "F2",
   "brand": "Ideal",
   "model_range": "Ideal Logic Max Combi C (C24 / C30 / C35, IE edition manual)",
   "category": "Ignition / flame",
   "meaning": "Flame loss.",
   "homeowner_action": "Check another gas appliance such as the hob works, the gas meter valve is on and, on a prepayment meter, there is credit. In freezing weather, check the plastic condensate pipe outside: if it is frozen, pour warm (not boiling) water along it. Then press reset once. If the code comes back, stop resetting.",
   "when_to_call_engineer": "Call a Gas Safe registered engineer if the gas supply is fine and the code returns after one reset. Ignition and flame faults involve gas, so this is engineer-only.",
   "engineer_after_one_reset": false,
   "page_url": "https://combicert.co.uk/boiler-fault-codes/ideal/#ideal-logic-max-f2",
   "source_manual": "Ideal Logic Max Combi C Installation & Servicing (C24IE, C30IE, C35IE)",
   "source_doc": "UIN 223440 A05",
   "source_pages": "User's section 8, Fault codes (PDF p. 80)",
   "source_url": "https://www.macblair.com/media/akeneo_connector/asset_files/L/o/Logic_Max_Combi_Boiler_C30_Installation_and_Servicing_Manual_76f3.pdf",
   "source_type": "trade-site mirror (no manufacturer-hosted copy found)"
  },
  {
   "id": "ideal-logic-max-l2",
   "code": "L2",
   "brand": "Ideal",
   "model_range": "Ideal Logic Max Combi C (C24 / C30 / C35, IE edition manual)",
   "category": "Ignition / flame",
   "meaning": "Ignition lockout: the boiler failed to light.",
   "homeowner_action": "Check another gas appliance such as the hob works, the gas meter valve is on and, on a prepayment meter, there is credit. In freezing weather, check the plastic condensate pipe outside: if it is frozen, pour warm (not boiling) water along it. Then press reset once. If the code comes back, stop resetting.",
   "when_to_call_engineer": "Call a Gas Safe registered engineer if the gas supply is fine and the code returns after one reset. Ignition and flame faults involve gas, so this is engineer-only.",
   "engineer_after_one_reset": false,
   "page_url": "https://combicert.co.uk/boiler-fault-codes/ideal/#ideal-logic-max-l2",
   "source_manual": "Ideal Logic Max Combi C Installation & Servicing (C24IE, C30IE, C35IE)",
   "source_doc": "UIN 223440 A05",
   "source_pages": "User's section 8, Fault codes (PDF p. 80)",
   "source_url": "https://www.macblair.com/media/akeneo_connector/asset_files/L/o/Logic_Max_Combi_Boiler_C30_Installation_and_Servicing_Manual_76f3.pdf",
   "source_type": "trade-site mirror (no manufacturer-hosted copy found)"
  },
  {
   "id": "ideal-logic-max-l6",
   "code": "L6",
   "brand": "Ideal",
   "model_range": "Ideal Logic Max Combi C (C24 / C30 / C35, IE edition manual)",
   "category": "Ignition / flame",
   "meaning": "False flame lockout.",
   "homeowner_action": "There is no homeowner check that fixes this code. Write down the full code, press reset once, and if it comes back leave the boiler off.",
   "when_to_call_engineer": "Call a Gas Safe registered engineer if the code comes back after one reset. Ignition and flame faults involve gas, so this is engineer-only.",
   "engineer_after_one_reset": true,
   "page_url": "https://combicert.co.uk/boiler-fault-codes/ideal/#ideal-logic-max-l6",
   "source_manual": "Ideal Logic Max Combi C Installation & Servicing (C24IE, C30IE, C35IE)",
   "source_doc": "UIN 223440 A05",
   "source_pages": "User's section 8, Fault codes (PDF p. 80)",
   "source_url": "https://www.macblair.com/media/akeneo_connector/asset_files/L/o/Logic_Max_Combi_Boiler_C30_Installation_and_Servicing_Manual_76f3.pdf",
   "source_type": "trade-site mirror (no manufacturer-hosted copy found)"
  },
  {
   "id": "ideal-logic-max-f1",
   "code": "F1",
   "brand": "Ideal",
   "model_range": "Ideal Logic Max Combi C (C24 / C30 / C35, IE edition manual)",
   "category": "Water pressure / circulation",
   "meaning": "Low water pressure.",
   "homeowner_action": "Look at the pressure gauge while the boiler is cold. If it is below about 1 bar, top it up with the filling loop exactly as your user guide shows, to about 1–1.5 bar or the figure in your guide, then close the loop fully. Check the radiator valves are open, then press reset once.",
   "when_to_call_engineer": "Call a Gas Safe registered engineer if you have to top up more than once every few months, the gauge goes above about 2.5 bar when hot, water drips from the outside overflow pipe, or the code returns after topping up.",
   "engineer_after_one_reset": false,
   "page_url": "https://combicert.co.uk/boiler-fault-codes/ideal/#ideal-logic-max-f1",
   "source_manual": "Ideal Logic Max Combi C Installation & Servicing (C24IE, C30IE, C35IE)",
   "source_doc": "UIN 223440 A05",
   "source_pages": "User's section 8, Fault codes (PDF p. 80)",
   "source_url": "https://www.macblair.com/media/akeneo_connector/asset_files/L/o/Logic_Max_Combi_Boiler_C30_Installation_and_Servicing_Manual_76f3.pdf",
   "source_type": "trade-site mirror (no manufacturer-hosted copy found)"
  },
  {
   "id": "ideal-logic-max-fu",
   "code": "FU",
   "brand": "Ideal",
   "model_range": "Ideal Logic Max Combi C (C24 / C30 / C35, IE edition manual)",
   "category": "Water pressure / circulation",
   "meaning": "Flow/return temperature difference greater than 50 °C.",
   "homeowner_action": "There is no homeowner check that fixes this code. Write down the full code, press reset once, and if it comes back leave the boiler off.",
   "when_to_call_engineer": "Call a Gas Safe registered engineer if you have to top up more than once every few months, the gauge goes above about 2.5 bar when hot, water drips from the outside overflow pipe, or the code returns after topping up.",
   "engineer_after_one_reset": true,
   "page_url": "https://combicert.co.uk/boiler-fault-codes/ideal/#ideal-logic-max-fu",
   "source_manual": "Ideal Logic Max Combi C Installation & Servicing (C24IE, C30IE, C35IE)",
   "source_doc": "UIN 223440 A05",
   "source_pages": "User's section 8, Fault codes (PDF p. 80)",
   "source_url": "https://www.macblair.com/media/akeneo_connector/asset_files/L/o/Logic_Max_Combi_Boiler_C30_Installation_and_Servicing_Manual_76f3.pdf",
   "source_type": "trade-site mirror (no manufacturer-hosted copy found)"
  },
  {
   "id": "ideal-logic-max-l1",
   "code": "L1",
   "brand": "Ideal",
   "model_range": "Ideal Logic Max Combi C (C24 / C30 / C35, IE edition manual)",
   "category": "Temperature / overheat",
   "meaning": "Flow temperature overheat or no water flow.",
   "homeowner_action": "Let the boiler cool for 20 to 30 minutes, then press reset once. If the code comes back, leave the boiler off.",
   "when_to_call_engineer": "Call a Gas Safe registered engineer if the code comes back after one reset. Overheat shut-downs are safety devices doing their job, so this is engineer-only.",
   "engineer_after_one_reset": true,
   "page_url": "https://combicert.co.uk/boiler-fault-codes/ideal/#ideal-logic-max-l1",
   "source_manual": "Ideal Logic Max Combi C Installation & Servicing (C24IE, C30IE, C35IE)",
   "source_doc": "UIN 223440 A05",
   "source_pages": "User's section 8, Fault codes (PDF p. 80)",
   "source_url": "https://www.macblair.com/media/akeneo_connector/asset_files/L/o/Logic_Max_Combi_Boiler_C30_Installation_and_Servicing_Manual_76f3.pdf",
   "source_type": "trade-site mirror (no manufacturer-hosted copy found)"
  },
  {
   "id": "ideal-logic-max-f3",
   "code": "F3",
   "brand": "Ideal",
   "model_range": "Ideal Logic Max Combi C (C24 / C30 / C35, IE edition manual)",
   "category": "Flue / fan / air",
   "meaning": "Fan fault.",
   "homeowner_action": "There is no homeowner check that fixes this code. Write down the full code, press reset once, and if it comes back leave the boiler off.",
   "when_to_call_engineer": "Call a Gas Safe registered engineer if the terminal looks clear and the code returns. Flue and fan faults can affect how combustion gases leave your home, so this is engineer-only.",
   "engineer_after_one_reset": true,
   "page_url": "https://combicert.co.uk/boiler-fault-codes/ideal/#ideal-logic-max-f3",
   "source_manual": "Ideal Logic Max Combi C Installation & Servicing (C24IE, C30IE, C35IE)",
   "source_doc": "UIN 223440 A05",
   "source_pages": "User's section 8, Fault codes (PDF p. 80)",
   "source_url": "https://www.macblair.com/media/akeneo_connector/asset_files/L/o/Logic_Max_Combi_Boiler_C30_Installation_and_Servicing_Manual_76f3.pdf",
   "source_type": "trade-site mirror (no manufacturer-hosted copy found)"
  },
  {
   "id": "ideal-logic-max-f4",
   "code": "F4",
   "brand": "Ideal",
   "model_range": "Ideal Logic Max Combi C (C24 / C30 / C35, IE edition manual)",
   "category": "Sensors / thermistors",
   "meaning": "Flow thermistor fault.",
   "homeowner_action": "Write down the full code. Check the boiler has power, then switch it off and on at its mains switch or press reset once. If the code comes back, leave it there: sensors are inside the casing.",
   "when_to_call_engineer": "Call a Gas Safe registered engineer if the code returns. Testing and replacing sensors means opening the casing, so this is engineer-only.",
   "engineer_after_one_reset": true,
   "page_url": "https://combicert.co.uk/boiler-fault-codes/ideal/#ideal-logic-max-f4",
   "source_manual": "Ideal Logic Max Combi C Installation & Servicing (C24IE, C30IE, C35IE)",
   "source_doc": "UIN 223440 A05",
   "source_pages": "User's section 8, Fault codes (PDF p. 80)",
   "source_url": "https://www.macblair.com/media/akeneo_connector/asset_files/L/o/Logic_Max_Combi_Boiler_C30_Installation_and_Servicing_Manual_76f3.pdf",
   "source_type": "trade-site mirror (no manufacturer-hosted copy found)"
  },
  {
   "id": "ideal-logic-max-l4",
   "code": "L4",
   "brand": "Ideal",
   "model_range": "Ideal Logic Max Combi C (C24 / C30 / C35, IE edition manual)",
   "category": "Sensors / thermistors",
   "meaning": "Flow thermistor fault (locking version).",
   "homeowner_action": "Write down the full code. Check the boiler has power, then switch it off and on at its mains switch or press reset once. If the code comes back, leave it there: sensors are inside the casing.",
   "when_to_call_engineer": "Call a Gas Safe registered engineer if the code returns. Testing and replacing sensors means opening the casing, so this is engineer-only.",
   "engineer_after_one_reset": true,
   "page_url": "https://combicert.co.uk/boiler-fault-codes/ideal/#ideal-logic-max-l4",
   "source_manual": "Ideal Logic Max Combi C Installation & Servicing (C24IE, C30IE, C35IE)",
   "source_doc": "UIN 223440 A05",
   "source_pages": "User's section 8, Fault codes (PDF p. 80)",
   "source_url": "https://www.macblair.com/media/akeneo_connector/asset_files/L/o/Logic_Max_Combi_Boiler_C30_Installation_and_Servicing_Manual_76f3.pdf",
   "source_type": "trade-site mirror (no manufacturer-hosted copy found)"
  },
  {
   "id": "ideal-logic-max-f5",
   "code": "F5",
   "brand": "Ideal",
   "model_range": "Ideal Logic Max Combi C (C24 / C30 / C35, IE edition manual)",
   "category": "Sensors / thermistors",
   "meaning": "Return thermistor fault.",
   "homeowner_action": "Write down the full code. Check the boiler has power, then switch it off and on at its mains switch or press reset once. If the code comes back, leave it there: sensors are inside the casing.",
   "when_to_call_engineer": "Call a Gas Safe registered engineer if the code returns. Testing and replacing sensors means opening the casing, so this is engineer-only.",
   "engineer_after_one_reset": true,
   "page_url": "https://combicert.co.uk/boiler-fault-codes/ideal/#ideal-logic-max-f5",
   "source_manual": "Ideal Logic Max Combi C Installation & Servicing (C24IE, C30IE, C35IE)",
   "source_doc": "UIN 223440 A05",
   "source_pages": "User's section 8, Fault codes (PDF p. 80)",
   "source_url": "https://www.macblair.com/media/akeneo_connector/asset_files/L/o/Logic_Max_Combi_Boiler_C30_Installation_and_Servicing_Manual_76f3.pdf",
   "source_type": "trade-site mirror (no manufacturer-hosted copy found)"
  },
  {
   "id": "ideal-logic-max-l5",
   "code": "L5",
   "brand": "Ideal",
   "model_range": "Ideal Logic Max Combi C (C24 / C30 / C35, IE edition manual)",
   "category": "Sensors / thermistors",
   "meaning": "Return thermistor fault (locking version).",
   "homeowner_action": "Write down the full code. Check the boiler has power, then switch it off and on at its mains switch or press reset once. If the code comes back, leave it there: sensors are inside the casing.",
   "when_to_call_engineer": "Call a Gas Safe registered engineer if the code returns. Testing and replacing sensors means opening the casing, so this is engineer-only.",
   "engineer_after_one_reset": true,
   "page_url": "https://combicert.co.uk/boiler-fault-codes/ideal/#ideal-logic-max-l5",
   "source_manual": "Ideal Logic Max Combi C Installation & Servicing (C24IE, C30IE, C35IE)",
   "source_doc": "UIN 223440 A05",
   "source_pages": "User's section 8, Fault codes (PDF p. 80)",
   "source_url": "https://www.macblair.com/media/akeneo_connector/asset_files/L/o/Logic_Max_Combi_Boiler_C30_Installation_and_Servicing_Manual_76f3.pdf",
   "source_type": "trade-site mirror (no manufacturer-hosted copy found)"
  },
  {
   "id": "ideal-logic-max-f6",
   "code": "F6",
   "brand": "Ideal",
   "model_range": "Ideal Logic Max Combi C (C24 / C30 / C35, IE edition manual)",
   "category": "Sensors / thermistors",
   "meaning": "Outside sensor failure.",
   "homeowner_action": "Nothing urgent: the boiler normally keeps heating without the outdoor sensor, using a fixed setting. Press reset once to see if it clears.",
   "when_to_call_engineer": "Call a Gas Safe registered engineer if the code returns. Testing and replacing sensors means opening the casing, so this is engineer-only.",
   "engineer_after_one_reset": true,
   "page_url": "https://combicert.co.uk/boiler-fault-codes/ideal/#ideal-logic-max-f6",
   "source_manual": "Ideal Logic Max Combi C Installation & Servicing (C24IE, C30IE, C35IE)",
   "source_doc": "UIN 223440 A05",
   "source_pages": "User's section 8, Fault codes (PDF p. 80)",
   "source_url": "https://www.macblair.com/media/akeneo_connector/asset_files/L/o/Logic_Max_Combi_Boiler_C30_Installation_and_Servicing_Manual_76f3.pdf",
   "source_type": "trade-site mirror (no manufacturer-hosted copy found)"
  },
  {
   "id": "ideal-logic-max-fa",
   "code": "FA",
   "brand": "Ideal",
   "model_range": "Ideal Logic Max Combi C (C24 / C30 / C35, IE edition manual)",
   "category": "Sensors / thermistors",
   "meaning": "Negative flow/return thermistor differential: the return reads hotter than the flow.",
   "homeowner_action": "Write down the full code. Check the boiler has power, then switch it off and on at its mains switch or press reset once. If the code comes back, leave it there: sensors are inside the casing.",
   "when_to_call_engineer": "Call a Gas Safe registered engineer if the code returns. Testing and replacing sensors means opening the casing, so this is engineer-only.",
   "engineer_after_one_reset": true,
   "page_url": "https://combicert.co.uk/boiler-fault-codes/ideal/#ideal-logic-max-fa",
   "source_manual": "Ideal Logic Max Combi C Installation & Servicing (C24IE, C30IE, C35IE)",
   "source_doc": "UIN 223440 A05",
   "source_pages": "User's section 8, Fault codes (PDF p. 80)",
   "source_url": "https://www.macblair.com/media/akeneo_connector/asset_files/L/o/Logic_Max_Combi_Boiler_C30_Installation_and_Servicing_Manual_76f3.pdf",
   "source_type": "trade-site mirror (no manufacturer-hosted copy found)"
  },
  {
   "id": "ideal-logic-max-f7",
   "code": "F7",
   "brand": "Ideal",
   "model_range": "Ideal Logic Max Combi C (C24 / C30 / C35, IE edition manual)",
   "category": "PCB / electrical",
   "meaning": "Low mains voltage.",
   "homeowner_action": "Check whether lights are dimming or other appliances are struggling. If they are, contact an electrician or your electricity network operator (call 105 for a power cut). Then press reset once.",
   "when_to_call_engineer": "Call a Gas Safe registered engineer if your mains supply is fine and the code continues, so the boiler's own supply and board can be checked.",
   "engineer_after_one_reset": false,
   "page_url": "https://combicert.co.uk/boiler-fault-codes/ideal/#ideal-logic-max-f7",
   "source_manual": "Ideal Logic Max Combi C Installation & Servicing (C24IE, C30IE, C35IE)",
   "source_doc": "UIN 223440 A05",
   "source_pages": "User's section 8, Fault codes (PDF p. 80)",
   "source_url": "https://www.macblair.com/media/akeneo_connector/asset_files/L/o/Logic_Max_Combi_Boiler_C30_Installation_and_Servicing_Manual_76f3.pdf",
   "source_type": "trade-site mirror (no manufacturer-hosted copy found)"
  },
  {
   "id": "ideal-logic-max-f9",
   "code": "F9",
   "brand": "Ideal",
   "model_range": "Ideal Logic Max Combi C (C24 / C30 / C35, IE edition manual)",
   "category": "PCB / electrical",
   "meaning": "Unconfigured or faulty PCB, or a gas valve short circuit.",
   "homeowner_action": "Write down the full code. Check the boiler has power and nothing else in the house has tripped, then switch the boiler off and on at its mains switch or press reset once. If the code comes back, leave the boiler off.",
   "when_to_call_engineer": "Call a Gas Safe registered engineer if the code returns. Board, wiring and gas valve checks mean opening the casing, so this is engineer-only.",
   "engineer_after_one_reset": true,
   "page_url": "https://combicert.co.uk/boiler-fault-codes/ideal/#ideal-logic-max-f9",
   "source_manual": "Ideal Logic Max Combi C Installation & Servicing (C24IE, C30IE, C35IE)",
   "source_doc": "UIN 223440 A05",
   "source_pages": "User's section 8, Fault codes (PDF p. 80)",
   "source_url": "https://www.macblair.com/media/akeneo_connector/asset_files/L/o/Logic_Max_Combi_Boiler_C30_Installation_and_Servicing_Manual_76f3.pdf",
   "source_type": "trade-site mirror (no manufacturer-hosted copy found)"
  },
  {
   "id": "ideal-logic-max-l9",
   "code": "L9",
   "brand": "Ideal",
   "model_range": "Ideal Logic Max Combi C (C24 / C30 / C35, IE edition manual)",
   "category": "PCB / electrical",
   "meaning": "Unconfigured or faulty PCB, or a gas valve short circuit (locking version).",
   "homeowner_action": "Write down the full code. Check the boiler has power and nothing else in the house has tripped, then switch the boiler off and on at its mains switch or press reset once. If the code comes back, leave the boiler off.",
   "when_to_call_engineer": "Call a Gas Safe registered engineer if the code returns. Board, wiring and gas valve checks mean opening the casing, so this is engineer-only.",
   "engineer_after_one_reset": true,
   "page_url": "https://combicert.co.uk/boiler-fault-codes/ideal/#ideal-logic-max-l9",
   "source_manual": "Ideal Logic Max Combi C Installation & Servicing (C24IE, C30IE, C35IE)",
   "source_doc": "UIN 223440 A05",
   "source_pages": "User's section 8, Fault codes (PDF p. 80)",
   "source_url": "https://www.macblair.com/media/akeneo_connector/asset_files/L/o/Logic_Max_Combi_Boiler_C30_Installation_and_Servicing_Manual_76f3.pdf",
   "source_type": "trade-site mirror (no manufacturer-hosted copy found)"
  },
  {
   "id": "ideal-logic-max-lc",
   "code": "LC",
   "brand": "Ideal",
   "model_range": "Ideal Logic Max Combi C (C24 / C30 / C35, IE edition manual)",
   "category": "Other / controls",
   "meaning": "Five boiler resets within 15 minutes.",
   "homeowner_action": "Stop resetting. Switch the boiler off at its mains switch, wait at least 15 minutes, then check the gas supply and pressure before trying one more reset.",
   "when_to_call_engineer": "Call a Gas Safe registered engineer now. Repeated resets mean an underlying fault is still there; tell them which code you were resetting.",
   "engineer_after_one_reset": false,
   "page_url": "https://combicert.co.uk/boiler-fault-codes/ideal/#ideal-logic-max-lc",
   "source_manual": "Ideal Logic Max Combi C Installation & Servicing (C24IE, C30IE, C35IE)",
   "source_doc": "UIN 223440 A05",
   "source_pages": "User's section 8, Fault codes (PDF p. 80)",
   "source_url": "https://www.macblair.com/media/akeneo_connector/asset_files/L/o/Logic_Max_Combi_Boiler_C30_Installation_and_Servicing_Manual_76f3.pdf",
   "source_type": "trade-site mirror (no manufacturer-hosted copy found)"
  },
  {
   "id": "ideal-logic-f2",
   "code": "F2",
   "brand": "Ideal",
   "model_range": "Ideal Logic Combi (24 / 30 / 35)",
   "category": "Ignition / flame",
   "meaning": "Flame loss.",
   "homeowner_action": "Check another gas appliance such as the hob works, the gas meter valve is on and, on a prepayment meter, there is credit. In freezing weather, check the plastic condensate pipe outside: if it is frozen, pour warm (not boiling) water along it. Then press reset once. If the code comes back, stop resetting.",
   "when_to_call_engineer": "Call a Gas Safe registered engineer if the gas supply is fine and the code returns after one reset. Ignition and flame faults involve gas, so this is engineer-only.",
   "engineer_after_one_reset": false,
   "page_url": "https://combicert.co.uk/boiler-fault-codes/ideal/#ideal-logic-f2",
   "source_manual": "Ideal Logic Combi 24, 30, 35 Installation and Servicing (with User's Guide)",
   "source_doc": "UIN 204626 A12 (January 2014)",
   "source_pages": "User's Guide p. 7 (PDF p. 71), Fault codes table",
   "source_url": "https://downloads.ctfassets.net/q60ipmqfy5x6/7AlnJVoNEN1WSye7kgnBM8/2d404737da761fa1596e26cfb667af30/Ideal_Logic_Combi_Installation___Servicing.pdf",
   "source_type": "manufacturer"
  },
  {
   "id": "ideal-logic-l2",
   "code": "L2",
   "brand": "Ideal",
   "model_range": "Ideal Logic Combi (24 / 30 / 35)",
   "category": "Ignition / flame",
   "meaning": "Flame loss lockout (this manual lists L2 alongside F2 as flame loss).",
   "homeowner_action": "Check another gas appliance such as the hob works, the gas meter valve is on and, on a prepayment meter, there is credit. In freezing weather, check the plastic condensate pipe outside: if it is frozen, pour warm (not boiling) water along it. Then press reset once. If the code comes back, stop resetting.",
   "when_to_call_engineer": "Call a Gas Safe registered engineer if the gas supply is fine and the code returns after one reset. Ignition and flame faults involve gas, so this is engineer-only.",
   "engineer_after_one_reset": false,
   "page_url": "https://combicert.co.uk/boiler-fault-codes/ideal/#ideal-logic-l2",
   "source_manual": "Ideal Logic Combi 24, 30, 35 Installation and Servicing (with User's Guide)",
   "source_doc": "UIN 204626 A12 (January 2014)",
   "source_pages": "User's Guide p. 7 (PDF p. 71), Fault codes table",
   "source_url": "https://downloads.ctfassets.net/q60ipmqfy5x6/7AlnJVoNEN1WSye7kgnBM8/2d404737da761fa1596e26cfb667af30/Ideal_Logic_Combi_Installation___Servicing.pdf",
   "source_type": "manufacturer"
  },
  {
   "id": "ideal-logic-l6",
   "code": "L6",
   "brand": "Ideal",
   "model_range": "Ideal Logic Combi (24 / 30 / 35)",
   "category": "Ignition / flame",
   "meaning": "False flame lockout: a flame was detected when there should not be one.",
   "homeowner_action": "There is no homeowner check that fixes this code. Write down the full code, press reset once, and if it comes back leave the boiler off.",
   "when_to_call_engineer": "Call a Gas Safe registered engineer if the code comes back after one reset. Ignition and flame faults involve gas, so this is engineer-only.",
   "engineer_after_one_reset": true,
   "page_url": "https://combicert.co.uk/boiler-fault-codes/ideal/#ideal-logic-l6",
   "source_manual": "Ideal Logic Combi 24, 30, 35 Installation and Servicing (with User's Guide)",
   "source_doc": "UIN 204626 A12 (January 2014)",
   "source_pages": "User's Guide p. 7 (PDF p. 71), Fault codes table",
   "source_url": "https://downloads.ctfassets.net/q60ipmqfy5x6/7AlnJVoNEN1WSye7kgnBM8/2d404737da761fa1596e26cfb667af30/Ideal_Logic_Combi_Installation___Servicing.pdf",
   "source_type": "manufacturer"
  },
  {
   "id": "ideal-logic-f1",
   "code": "F1",
   "brand": "Ideal",
   "model_range": "Ideal Logic Combi (24 / 30 / 35)",
   "category": "Water pressure / circulation",
   "meaning": "Low water pressure.",
   "homeowner_action": "Look at the pressure gauge while the boiler is cold. If it is below about 1 bar, top it up with the filling loop exactly as your user guide shows, to about 1–1.5 bar or the figure in your guide, then close the loop fully. Check the radiator valves are open, then press reset once.",
   "when_to_call_engineer": "Call a Gas Safe registered engineer if you have to top up more than once every few months, the gauge goes above about 2.5 bar when hot, water drips from the outside overflow pipe, or the code returns after topping up.",
   "engineer_after_one_reset": false,
   "page_url": "https://combicert.co.uk/boiler-fault-codes/ideal/#ideal-logic-f1",
   "source_manual": "Ideal Logic Combi 24, 30, 35 Installation and Servicing (with User's Guide)",
   "source_doc": "UIN 204626 A12 (January 2014)",
   "source_pages": "User's Guide p. 7 (PDF p. 71), Fault codes table",
   "source_url": "https://downloads.ctfassets.net/q60ipmqfy5x6/7AlnJVoNEN1WSye7kgnBM8/2d404737da761fa1596e26cfb667af30/Ideal_Logic_Combi_Installation___Servicing.pdf",
   "source_type": "manufacturer"
  },
  {
   "id": "ideal-logic-l1",
   "code": "L1",
   "brand": "Ideal",
   "model_range": "Ideal Logic Combi (24 / 30 / 35)",
   "category": "Temperature / overheat",
   "meaning": "Flow temperature overheat or no water flow.",
   "homeowner_action": "Let the boiler cool for 20 to 30 minutes, then press reset once. If the code comes back, leave the boiler off.",
   "when_to_call_engineer": "Call a Gas Safe registered engineer if the code comes back after one reset. Overheat shut-downs are safety devices doing their job, so this is engineer-only.",
   "engineer_after_one_reset": true,
   "page_url": "https://combicert.co.uk/boiler-fault-codes/ideal/#ideal-logic-l1",
   "source_manual": "Ideal Logic Combi 24, 30, 35 Installation and Servicing (with User's Guide)",
   "source_doc": "UIN 204626 A12 (January 2014)",
   "source_pages": "User's Guide p. 7 (PDF p. 71), Fault codes table",
   "source_url": "https://downloads.ctfassets.net/q60ipmqfy5x6/7AlnJVoNEN1WSye7kgnBM8/2d404737da761fa1596e26cfb667af30/Ideal_Logic_Combi_Installation___Servicing.pdf",
   "source_type": "manufacturer"
  },
  {
   "id": "ideal-logic-f3",
   "code": "F3",
   "brand": "Ideal",
   "model_range": "Ideal Logic Combi (24 / 30 / 35)",
   "category": "Flue / fan / air",
   "meaning": "Fan fault.",
   "homeowner_action": "There is no homeowner check that fixes this code. Write down the full code, press reset once, and if it comes back leave the boiler off.",
   "when_to_call_engineer": "Call a Gas Safe registered engineer if the terminal looks clear and the code returns. Flue and fan faults can affect how combustion gases leave your home, so this is engineer-only.",
   "engineer_after_one_reset": true,
   "page_url": "https://combicert.co.uk/boiler-fault-codes/ideal/#ideal-logic-f3",
   "source_manual": "Ideal Logic Combi 24, 30, 35 Installation and Servicing (with User's Guide)",
   "source_doc": "UIN 204626 A12 (January 2014)",
   "source_pages": "User's Guide p. 7 (PDF p. 71), Fault codes table",
   "source_url": "https://downloads.ctfassets.net/q60ipmqfy5x6/7AlnJVoNEN1WSye7kgnBM8/2d404737da761fa1596e26cfb667af30/Ideal_Logic_Combi_Installation___Servicing.pdf",
   "source_type": "manufacturer"
  },
  {
   "id": "ideal-logic-f4",
   "code": "F4",
   "brand": "Ideal",
   "model_range": "Ideal Logic Combi (24 / 30 / 35)",
   "category": "Sensors / thermistors",
   "meaning": "Flow thermistor fault.",
   "homeowner_action": "Write down the full code. Check the boiler has power, then switch it off and on at its mains switch or press reset once. If the code comes back, leave it there: sensors are inside the casing.",
   "when_to_call_engineer": "Call a Gas Safe registered engineer if the code returns. Testing and replacing sensors means opening the casing, so this is engineer-only.",
   "engineer_after_one_reset": true,
   "page_url": "https://combicert.co.uk/boiler-fault-codes/ideal/#ideal-logic-f4",
   "source_manual": "Ideal Logic Combi 24, 30, 35 Installation and Servicing (with User's Guide)",
   "source_doc": "UIN 204626 A12 (January 2014)",
   "source_pages": "User's Guide p. 7 (PDF p. 71), Fault codes table",
   "source_url": "https://downloads.ctfassets.net/q60ipmqfy5x6/7AlnJVoNEN1WSye7kgnBM8/2d404737da761fa1596e26cfb667af30/Ideal_Logic_Combi_Installation___Servicing.pdf",
   "source_type": "manufacturer"
  },
  {
   "id": "ideal-logic-f5",
   "code": "F5",
   "brand": "Ideal",
   "model_range": "Ideal Logic Combi (24 / 30 / 35)",
   "category": "Sensors / thermistors",
   "meaning": "Return thermistor fault.",
   "homeowner_action": "Write down the full code. Check the boiler has power, then switch it off and on at its mains switch or press reset once. If the code comes back, leave it there: sensors are inside the casing.",
   "when_to_call_engineer": "Call a Gas Safe registered engineer if the code returns. Testing and replacing sensors means opening the casing, so this is engineer-only.",
   "engineer_after_one_reset": true,
   "page_url": "https://combicert.co.uk/boiler-fault-codes/ideal/#ideal-logic-f5",
   "source_manual": "Ideal Logic Combi 24, 30, 35 Installation and Servicing (with User's Guide)",
   "source_doc": "UIN 204626 A12 (January 2014)",
   "source_pages": "User's Guide p. 7 (PDF p. 71), Fault codes table",
   "source_url": "https://downloads.ctfassets.net/q60ipmqfy5x6/7AlnJVoNEN1WSye7kgnBM8/2d404737da761fa1596e26cfb667af30/Ideal_Logic_Combi_Installation___Servicing.pdf",
   "source_type": "manufacturer"
  },
  {
   "id": "ideal-logic-f6",
   "code": "F6",
   "brand": "Ideal",
   "model_range": "Ideal Logic Combi (24 / 30 / 35)",
   "category": "Sensors / thermistors",
   "meaning": "Outside sensor failure.",
   "homeowner_action": "Nothing urgent: the boiler normally keeps heating without the outdoor sensor, using a fixed setting. Press reset once to see if it clears.",
   "when_to_call_engineer": "Call a Gas Safe registered engineer if the code returns. Testing and replacing sensors means opening the casing, so this is engineer-only.",
   "engineer_after_one_reset": true,
   "page_url": "https://combicert.co.uk/boiler-fault-codes/ideal/#ideal-logic-f6",
   "source_manual": "Ideal Logic Combi 24, 30, 35 Installation and Servicing (with User's Guide)",
   "source_doc": "UIN 204626 A12 (January 2014)",
   "source_pages": "User's Guide p. 7 (PDF p. 71), Fault codes table",
   "source_url": "https://downloads.ctfassets.net/q60ipmqfy5x6/7AlnJVoNEN1WSye7kgnBM8/2d404737da761fa1596e26cfb667af30/Ideal_Logic_Combi_Installation___Servicing.pdf",
   "source_type": "manufacturer"
  },
  {
   "id": "ideal-logic-f7",
   "code": "F7",
   "brand": "Ideal",
   "model_range": "Ideal Logic Combi (24 / 30 / 35)",
   "category": "PCB / electrical",
   "meaning": "Low mains voltage.",
   "homeowner_action": "Check whether lights are dimming or other appliances are struggling. If they are, contact an electrician or your electricity network operator (call 105 for a power cut). Then press reset once.",
   "when_to_call_engineer": "Call a Gas Safe registered engineer if your mains supply is fine and the code continues, so the boiler's own supply and board can be checked.",
   "engineer_after_one_reset": false,
   "page_url": "https://combicert.co.uk/boiler-fault-codes/ideal/#ideal-logic-f7",
   "source_manual": "Ideal Logic Combi 24, 30, 35 Installation and Servicing (with User's Guide)",
   "source_doc": "UIN 204626 A12 (January 2014)",
   "source_pages": "User's Guide p. 7 (PDF p. 71), Fault codes table",
   "source_url": "https://downloads.ctfassets.net/q60ipmqfy5x6/7AlnJVoNEN1WSye7kgnBM8/2d404737da761fa1596e26cfb667af30/Ideal_Logic_Combi_Installation___Servicing.pdf",
   "source_type": "manufacturer"
  },
  {
   "id": "ideal-logic-f9",
   "code": "F9",
   "brand": "Ideal",
   "model_range": "Ideal Logic Combi (24 / 30 / 35)",
   "category": "PCB / electrical",
   "meaning": "Unconfigured PCB.",
   "homeowner_action": "Write down the full code. Check the boiler has power and nothing else in the house has tripped, then switch the boiler off and on at its mains switch or press reset once. If the code comes back, leave the boiler off.",
   "when_to_call_engineer": "Call a Gas Safe registered engineer if the code returns. Board, wiring and gas valve checks mean opening the casing, so this is engineer-only.",
   "engineer_after_one_reset": true,
   "page_url": "https://combicert.co.uk/boiler-fault-codes/ideal/#ideal-logic-f9",
   "source_manual": "Ideal Logic Combi 24, 30, 35 Installation and Servicing (with User's Guide)",
   "source_doc": "UIN 204626 A12 (January 2014)",
   "source_pages": "User's Guide p. 7 (PDF p. 71), Fault codes table",
   "source_url": "https://downloads.ctfassets.net/q60ipmqfy5x6/7AlnJVoNEN1WSye7kgnBM8/2d404737da761fa1596e26cfb667af30/Ideal_Logic_Combi_Installation___Servicing.pdf",
   "source_type": "manufacturer"
  },
  {
   "id": "ideal-logic-c0",
   "code": "C0",
   "brand": "Ideal",
   "model_range": "Ideal Logic Combi (24 / 30 / 35)",
   "category": "PCB / electrical",
   "meaning": "BCC (boiler chip card) activation fault.",
   "homeowner_action": "Write down the full code. Check the boiler has power and nothing else in the house has tripped, then switch the boiler off and on at its mains switch or press reset once. If the code comes back, leave the boiler off.",
   "when_to_call_engineer": "Call a Gas Safe registered engineer if the code returns. Board, wiring and gas valve checks mean opening the casing, so this is engineer-only.",
   "engineer_after_one_reset": true,
   "page_url": "https://combicert.co.uk/boiler-fault-codes/ideal/#ideal-logic-c0",
   "source_manual": "Ideal Logic Combi 24, 30, 35 Installation and Servicing (with User's Guide)",
   "source_doc": "UIN 204626 A12 (January 2014)",
   "source_pages": "User's Guide p. 7 (PDF p. 71), Fault codes table",
   "source_url": "https://downloads.ctfassets.net/q60ipmqfy5x6/7AlnJVoNEN1WSye7kgnBM8/2d404737da761fa1596e26cfb667af30/Ideal_Logic_Combi_Installation___Servicing.pdf",
   "source_type": "manufacturer"
  },
  {
   "id": "ideal-logic-c2",
   "code": "C2",
   "brand": "Ideal",
   "model_range": "Ideal Logic Combi (24 / 30 / 35)",
   "category": "PCB / electrical",
   "meaning": "BCC (boiler chip card) fault.",
   "homeowner_action": "Write down the full code. Check the boiler has power and nothing else in the house has tripped, then switch the boiler off and on at its mains switch or press reset once. If the code comes back, leave the boiler off.",
   "when_to_call_engineer": "Call a Gas Safe registered engineer if the code returns. Board, wiring and gas valve checks mean opening the casing, so this is engineer-only.",
   "engineer_after_one_reset": true,
   "page_url": "https://combicert.co.uk/boiler-fault-codes/ideal/#ideal-logic-c2",
   "source_manual": "Ideal Logic Combi 24, 30, 35 Installation and Servicing (with User's Guide)",
   "source_doc": "UIN 204626 A12 (January 2014)",
   "source_pages": "User's Guide p. 7 (PDF p. 71), Fault codes table",
   "source_url": "https://downloads.ctfassets.net/q60ipmqfy5x6/7AlnJVoNEN1WSye7kgnBM8/2d404737da761fa1596e26cfb667af30/Ideal_Logic_Combi_Installation___Servicing.pdf",
   "source_type": "manufacturer"
  },
  {
   "id": "ideal-logic-l5",
   "code": "L5",
   "brand": "Ideal",
   "model_range": "Ideal Logic Combi (24 / 30 / 35)",
   "category": "Other / controls",
   "meaning": "Five boiler resets within 15 minutes. The boiler blocks further resets.",
   "homeowner_action": "Stop resetting. Switch the boiler off at its mains switch, wait at least 15 minutes, then check the gas supply and pressure before trying one more reset.",
   "when_to_call_engineer": "Call a Gas Safe registered engineer now. Repeated resets mean an underlying fault is still there; tell them which code you were resetting.",
   "engineer_after_one_reset": false,
   "page_url": "https://combicert.co.uk/boiler-fault-codes/ideal/#ideal-logic-l5",
   "source_manual": "Ideal Logic Combi 24, 30, 35 Installation and Servicing (with User's Guide)",
   "source_doc": "UIN 204626 A12 (January 2014)",
   "source_pages": "User's Guide p. 7 (PDF p. 71), Fault codes table",
   "source_url": "https://downloads.ctfassets.net/q60ipmqfy5x6/7AlnJVoNEN1WSye7kgnBM8/2d404737da761fa1596e26cfb667af30/Ideal_Logic_Combi_Installation___Servicing.pdf",
   "source_type": "manufacturer"
  },
  {
   "id": "viessmann-e5",
   "code": "E5",
   "brand": "Viessmann",
   "model_range": "Vitodens 050-W (BPJC) and Vitodens 100-W (B1HA / B1KA)",
   "category": "Ignition / flame",
   "meaning": "Internal fault; the burner is blocked.",
   "homeowner_action": "There is no homeowner check that fixes this code. Write down the full code, press reset once, and if it comes back leave the boiler off.",
   "when_to_call_engineer": "Call a Gas Safe registered engineer if the code comes back after one reset. Ignition and flame faults involve gas, so this is engineer-only.",
   "engineer_after_one_reset": true,
   "page_url": "https://combicert.co.uk/boiler-fault-codes/viessmann/#viessmann-e5",
   "source_manual": "Vitodens 100-W Type B1HA, B1KA Installation and Service Instructions; Vitodens 050-W Type BPJC Installation and Service Instructions",
   "source_doc": "5677 216 GB (3/2015); 5513 085 GB (9/2014)",
   "source_pages": "100-W pp. 62–65 'Fault display'; 050-W PDF pp. 46–49 'Fault display'",
   "source_url": "https://viessmanndirect.co.uk/files/461be7f2-8610-4b7f-a942-a9d1010d8602/Vitodens%20100-W%20B1HA%20B1KA%20Installation%20and%20Service%20Manual.pdf",
   "source_type": "trade-site mirror (no manufacturer-hosted copy found)"
  },
  {
   "id": "viessmann-f3",
   "code": "F3",
   "brand": "Viessmann",
   "model_range": "Vitodens 050-W (BPJC) and Vitodens 100-W (B1HA / B1KA)",
   "category": "Ignition / flame",
   "meaning": "A flame signal is already present when the burner starts.",
   "homeowner_action": "There is no homeowner check that fixes this code. Write down the full code, press reset once, and if it comes back leave the boiler off.",
   "when_to_call_engineer": "Call a Gas Safe registered engineer if the code comes back after one reset. Ignition and flame faults involve gas, so this is engineer-only.",
   "engineer_after_one_reset": true,
   "page_url": "https://combicert.co.uk/boiler-fault-codes/viessmann/#viessmann-f3",
   "source_manual": "Vitodens 100-W Type B1HA, B1KA Installation and Service Instructions; Vitodens 050-W Type BPJC Installation and Service Instructions",
   "source_doc": "5677 216 GB (3/2015); 5513 085 GB (9/2014)",
   "source_pages": "100-W pp. 62–65 'Fault display'; 050-W PDF pp. 46–49 'Fault display'",
   "source_url": "https://viessmanndirect.co.uk/files/461be7f2-8610-4b7f-a942-a9d1010d8602/Vitodens%20100-W%20B1HA%20B1KA%20Installation%20and%20Service%20Manual.pdf",
   "source_type": "trade-site mirror (no manufacturer-hosted copy found)"
  },
  {
   "id": "viessmann-f4",
   "code": "F4",
   "brand": "Viessmann",
   "model_range": "Vitodens 050-W (BPJC) and Vitodens 100-W (B1HA / B1KA)",
   "category": "Ignition / flame",
   "meaning": "No flame signal detected: the boiler failed to light.",
   "homeowner_action": "Check another gas appliance such as the hob works, the gas meter valve is on and, on a prepayment meter, there is credit. In freezing weather, check the plastic condensate pipe outside: if it is frozen, pour warm (not boiling) water along it. Then press reset once. If the code comes back, stop resetting.",
   "when_to_call_engineer": "Call a Gas Safe registered engineer if the gas supply is fine and the code returns after one reset. Ignition and flame faults involve gas, so this is engineer-only.",
   "engineer_after_one_reset": false,
   "page_url": "https://combicert.co.uk/boiler-fault-codes/viessmann/#viessmann-f4",
   "source_manual": "Vitodens 100-W Type B1HA, B1KA Installation and Service Instructions; Vitodens 050-W Type BPJC Installation and Service Instructions",
   "source_doc": "5677 216 GB (3/2015); 5513 085 GB (9/2014)",
   "source_pages": "100-W pp. 62–65 'Fault display'; 050-W PDF pp. 46–49 'Fault display'",
   "source_url": "https://viessmanndirect.co.uk/files/461be7f2-8610-4b7f-a942-a9d1010d8602/Vitodens%20100-W%20B1HA%20B1KA%20Installation%20and%20Service%20Manual.pdf",
   "source_type": "trade-site mirror (no manufacturer-hosted copy found)"
  },
  {
   "id": "viessmann-f8",
   "code": "F8",
   "brand": "Viessmann",
   "model_range": "Vitodens 050-W (BPJC) and Vitodens 100-W (B1HA / B1KA)",
   "category": "Ignition / flame",
   "meaning": "The fuel (gas) valve closes too late.",
   "homeowner_action": "There is no homeowner check that fixes this code. Write down the full code, press reset once, and if it comes back leave the boiler off.",
   "when_to_call_engineer": "Call a Gas Safe registered engineer if the code comes back after one reset. Ignition and flame faults involve gas, so this is engineer-only.",
   "engineer_after_one_reset": true,
   "page_url": "https://combicert.co.uk/boiler-fault-codes/viessmann/#viessmann-f8",
   "source_manual": "Vitodens 100-W Type B1HA, B1KA Installation and Service Instructions; Vitodens 050-W Type BPJC Installation and Service Instructions",
   "source_doc": "5677 216 GB (3/2015); 5513 085 GB (9/2014)",
   "source_pages": "100-W pp. 62–65 'Fault display'; 050-W PDF pp. 46–49 'Fault display'",
   "source_url": "https://viessmanndirect.co.uk/files/461be7f2-8610-4b7f-a942-a9d1010d8602/Vitodens%20100-W%20B1HA%20B1KA%20Installation%20and%20Service%20Manual.pdf",
   "source_type": "trade-site mirror (no manufacturer-hosted copy found)"
  },
  {
   "id": "viessmann-e3",
   "code": "E3",
   "brand": "Viessmann",
   "model_range": "Vitodens 050-W (BPJC) and Vitodens 100-W (B1HA / B1KA)",
   "category": "Temperature / overheat",
   "meaning": "Fault in the safety chain; the burner is in a fault state.",
   "homeowner_action": "Let the boiler cool for 20 to 30 minutes, then press reset once. If the code comes back, leave the boiler off.",
   "when_to_call_engineer": "Call a Gas Safe registered engineer if the code comes back after one reset. Overheat shut-downs are safety devices doing their job, so this is engineer-only.",
   "engineer_after_one_reset": true,
   "page_url": "https://combicert.co.uk/boiler-fault-codes/viessmann/#viessmann-e3",
   "source_manual": "Vitodens 100-W Type B1HA, B1KA Installation and Service Instructions; Vitodens 050-W Type BPJC Installation and Service Instructions",
   "source_doc": "5677 216 GB (3/2015); 5513 085 GB (9/2014)",
   "source_pages": "100-W pp. 62–65 'Fault display'; 050-W PDF pp. 46–49 'Fault display'",
   "source_url": "https://viessmanndirect.co.uk/files/461be7f2-8610-4b7f-a942-a9d1010d8602/Vitodens%20100-W%20B1HA%20B1KA%20Installation%20and%20Service%20Manual.pdf",
   "source_type": "trade-site mirror (no manufacturer-hosted copy found)"
  },
  {
   "id": "viessmann-f1",
   "code": "F1",
   "brand": "Viessmann",
   "model_range": "Vitodens 050-W (BPJC) and Vitodens 100-W (B1HA / B1KA)",
   "category": "Temperature / overheat",
   "meaning": "Maximum flue gas temperature exceeded.",
   "homeowner_action": "Let the boiler cool for 20 to 30 minutes, then press reset once. If the code comes back, leave the boiler off.",
   "when_to_call_engineer": "Call a Gas Safe registered engineer if the code comes back after one reset. Overheat shut-downs are safety devices doing their job, so this is engineer-only.",
   "engineer_after_one_reset": true,
   "page_url": "https://combicert.co.uk/boiler-fault-codes/viessmann/#viessmann-f1",
   "source_manual": "Vitodens 100-W Type B1HA, B1KA Installation and Service Instructions; Vitodens 050-W Type BPJC Installation and Service Instructions",
   "source_doc": "5677 216 GB (3/2015); 5513 085 GB (9/2014)",
   "source_pages": "100-W pp. 62–65 'Fault display'; 050-W PDF pp. 46–49 'Fault display'",
   "source_url": "https://viessmanndirect.co.uk/files/461be7f2-8610-4b7f-a942-a9d1010d8602/Vitodens%20100-W%20B1HA%20B1KA%20Installation%20and%20Service%20Manual.pdf",
   "source_type": "trade-site mirror (no manufacturer-hosted copy found)"
  },
  {
   "id": "viessmann-f2",
   "code": "F2",
   "brand": "Viessmann",
   "model_range": "Vitodens 050-W (BPJC) and Vitodens 100-W (B1HA / B1KA)",
   "category": "Temperature / overheat",
   "meaning": "The temperature limiter (overheat stat) has tripped.",
   "homeowner_action": "Let the boiler cool for 20 to 30 minutes, then press reset once. If the code comes back, leave the boiler off.",
   "when_to_call_engineer": "Call a Gas Safe registered engineer if the code comes back after one reset. Overheat shut-downs are safety devices doing their job, so this is engineer-only.",
   "engineer_after_one_reset": true,
   "page_url": "https://combicert.co.uk/boiler-fault-codes/viessmann/#viessmann-f2",
   "source_manual": "Vitodens 100-W Type B1HA, B1KA Installation and Service Instructions; Vitodens 050-W Type BPJC Installation and Service Instructions",
   "source_doc": "5677 216 GB (3/2015); 5513 085 GB (9/2014)",
   "source_pages": "100-W pp. 62–65 'Fault display'; 050-W PDF pp. 46–49 'Fault display'",
   "source_url": "https://viessmanndirect.co.uk/files/461be7f2-8610-4b7f-a942-a9d1010d8602/Vitodens%20100-W%20B1HA%20B1KA%20Installation%20and%20Service%20Manual.pdf",
   "source_type": "trade-site mirror (no manufacturer-hosted copy found)"
  },
  {
   "id": "viessmann-f9",
   "code": "F9",
   "brand": "Viessmann",
   "model_range": "Vitodens 050-W (BPJC) and Vitodens 100-W (B1HA / B1KA)",
   "category": "Flue / fan / air",
   "meaning": "Fan speed too low during burner start.",
   "homeowner_action": "There is no homeowner check that fixes this code. Write down the full code, press reset once, and if it comes back leave the boiler off.",
   "when_to_call_engineer": "Call a Gas Safe registered engineer if the terminal looks clear and the code returns. Flue and fan faults can affect how combustion gases leave your home, so this is engineer-only.",
   "engineer_after_one_reset": true,
   "page_url": "https://combicert.co.uk/boiler-fault-codes/viessmann/#viessmann-f9",
   "source_manual": "Vitodens 100-W Type B1HA, B1KA Installation and Service Instructions; Vitodens 050-W Type BPJC Installation and Service Instructions",
   "source_doc": "5677 216 GB (3/2015); 5513 085 GB (9/2014)",
   "source_pages": "100-W pp. 62–65 'Fault display'; 050-W PDF pp. 46–49 'Fault display'",
   "source_url": "https://viessmanndirect.co.uk/files/461be7f2-8610-4b7f-a942-a9d1010d8602/Vitodens%20100-W%20B1HA%20B1KA%20Installation%20and%20Service%20Manual.pdf",
   "source_type": "trade-site mirror (no manufacturer-hosted copy found)"
  },
  {
   "id": "viessmann-fa",
   "code": "FA",
   "brand": "Viessmann",
   "model_range": "Vitodens 050-W (BPJC) and Vitodens 100-W (B1HA / B1KA)",
   "category": "Flue / fan / air",
   "meaning": "The fan did not reach its idle (stopped) state.",
   "homeowner_action": "There is no homeowner check that fixes this code. Write down the full code, press reset once, and if it comes back leave the boiler off.",
   "when_to_call_engineer": "Call a Gas Safe registered engineer if the terminal looks clear and the code returns. Flue and fan faults can affect how combustion gases leave your home, so this is engineer-only.",
   "engineer_after_one_reset": true,
   "page_url": "https://combicert.co.uk/boiler-fault-codes/viessmann/#viessmann-fa",
   "source_manual": "Vitodens 100-W Type B1HA, B1KA Installation and Service Instructions; Vitodens 050-W Type BPJC Installation and Service Instructions",
   "source_doc": "5677 216 GB (3/2015); 5513 085 GB (9/2014)",
   "source_pages": "100-W pp. 62–65 'Fault display'; 050-W PDF pp. 46–49 'Fault display'",
   "source_url": "https://viessmanndirect.co.uk/files/461be7f2-8610-4b7f-a942-a9d1010d8602/Vitodens%20100-W%20B1HA%20B1KA%20Installation%20and%20Service%20Manual.pdf",
   "source_type": "trade-site mirror (no manufacturer-hosted copy found)"
  },
  {
   "id": "viessmann-fc",
   "code": "FC",
   "brand": "Viessmann",
   "model_range": "Vitodens 050-W (BPJC) and Vitodens 100-W (B1HA / B1KA)",
   "category": "Flue / fan / air",
   "meaning": "Electrical fan control in the control unit is faulty.",
   "homeowner_action": "There is no homeowner check that fixes this code. Write down the full code, press reset once, and if it comes back leave the boiler off.",
   "when_to_call_engineer": "Call a Gas Safe registered engineer if the terminal looks clear and the code returns. Flue and fan faults can affect how combustion gases leave your home, so this is engineer-only.",
   "engineer_after_one_reset": true,
   "page_url": "https://combicert.co.uk/boiler-fault-codes/viessmann/#viessmann-fc",
   "source_manual": "Vitodens 100-W Type B1HA, B1KA Installation and Service Instructions; Vitodens 050-W Type BPJC Installation and Service Instructions",
   "source_doc": "5677 216 GB (3/2015); 5513 085 GB (9/2014)",
   "source_pages": "100-W pp. 62–65 'Fault display'; 050-W PDF pp. 46–49 'Fault display'",
   "source_url": "https://viessmanndirect.co.uk/files/461be7f2-8610-4b7f-a942-a9d1010d8602/Vitodens%20100-W%20B1HA%20B1KA%20Installation%20and%20Service%20Manual.pdf",
   "source_type": "trade-site mirror (no manufacturer-hosted copy found)"
  },
  {
   "id": "viessmann-10",
   "code": "10",
   "brand": "Viessmann",
   "model_range": "Vitodens 050-W (BPJC) and Vitodens 100-W (B1HA / B1KA)",
   "category": "Sensors / thermistors",
   "meaning": "Outside temperature sensor short circuit. The boiler keeps running at a constant temperature.",
   "homeowner_action": "Nothing urgent: the boiler normally keeps heating without the outdoor sensor, using a fixed setting. Press reset once to see if it clears.",
   "when_to_call_engineer": "Call a Gas Safe registered engineer if the code returns. Testing and replacing sensors means opening the casing, so this is engineer-only.",
   "engineer_after_one_reset": true,
   "page_url": "https://combicert.co.uk/boiler-fault-codes/viessmann/#viessmann-10",
   "source_manual": "Vitodens 100-W Type B1HA, B1KA Installation and Service Instructions; Vitodens 050-W Type BPJC Installation and Service Instructions",
   "source_doc": "5677 216 GB (3/2015); 5513 085 GB (9/2014)",
   "source_pages": "100-W pp. 62–65 'Fault display'; 050-W PDF pp. 46–49 'Fault display'",
   "source_url": "https://viessmanndirect.co.uk/files/461be7f2-8610-4b7f-a942-a9d1010d8602/Vitodens%20100-W%20B1HA%20B1KA%20Installation%20and%20Service%20Manual.pdf",
   "source_type": "trade-site mirror (no manufacturer-hosted copy found)"
  },
  {
   "id": "viessmann-18",
   "code": "18",
   "brand": "Viessmann",
   "model_range": "Vitodens 050-W (BPJC) and Vitodens 100-W (B1HA / B1KA)",
   "category": "Sensors / thermistors",
   "meaning": "Outside temperature sensor lead break. The boiler keeps running at a constant temperature.",
   "homeowner_action": "Nothing urgent: the boiler normally keeps heating without the outdoor sensor, using a fixed setting. Press reset once to see if it clears.",
   "when_to_call_engineer": "Call a Gas Safe registered engineer if the code returns. Testing and replacing sensors means opening the casing, so this is engineer-only.",
   "engineer_after_one_reset": true,
   "page_url": "https://combicert.co.uk/boiler-fault-codes/viessmann/#viessmann-18",
   "source_manual": "Vitodens 100-W Type B1HA, B1KA Installation and Service Instructions; Vitodens 050-W Type BPJC Installation and Service Instructions",
   "source_doc": "5677 216 GB (3/2015); 5513 085 GB (9/2014)",
   "source_pages": "100-W pp. 62–65 'Fault display'; 050-W PDF pp. 46–49 'Fault display'",
   "source_url": "https://viessmanndirect.co.uk/files/461be7f2-8610-4b7f-a942-a9d1010d8602/Vitodens%20100-W%20B1HA%20B1KA%20Installation%20and%20Service%20Manual.pdf",
   "source_type": "trade-site mirror (no manufacturer-hosted copy found)"
  },
  {
   "id": "viessmann-30",
   "code": "30",
   "brand": "Viessmann",
   "model_range": "Vitodens 050-W (BPJC) and Vitodens 100-W (B1HA / B1KA)",
   "category": "Sensors / thermistors",
   "meaning": "Boiler water temperature sensor short circuit. The burner is blocked.",
   "homeowner_action": "Write down the full code. Check the boiler has power, then switch it off and on at its mains switch or press reset once. If the code comes back, leave it there: sensors are inside the casing.",
   "when_to_call_engineer": "Call a Gas Safe registered engineer if the code returns. Testing and replacing sensors means opening the casing, so this is engineer-only.",
   "engineer_after_one_reset": true,
   "page_url": "https://combicert.co.uk/boiler-fault-codes/viessmann/#viessmann-30",
   "source_manual": "Vitodens 100-W Type B1HA, B1KA Installation and Service Instructions; Vitodens 050-W Type BPJC Installation and Service Instructions",
   "source_doc": "5677 216 GB (3/2015); 5513 085 GB (9/2014)",
   "source_pages": "100-W pp. 62–65 'Fault display'; 050-W PDF pp. 46–49 'Fault display'",
   "source_url": "https://viessmanndirect.co.uk/files/461be7f2-8610-4b7f-a942-a9d1010d8602/Vitodens%20100-W%20B1HA%20B1KA%20Installation%20and%20Service%20Manual.pdf",
   "source_type": "trade-site mirror (no manufacturer-hosted copy found)"
  },
  {
   "id": "viessmann-38",
   "code": "38",
   "brand": "Viessmann",
   "model_range": "Vitodens 050-W (BPJC) and Vitodens 100-W (B1HA / B1KA)",
   "category": "Sensors / thermistors",
   "meaning": "Boiler water temperature sensor lead break. The burner is blocked.",
   "homeowner_action": "Write down the full code. Check the boiler has power, then switch it off and on at its mains switch or press reset once. If the code comes back, leave it there: sensors are inside the casing.",
   "when_to_call_engineer": "Call a Gas Safe registered engineer if the code returns. Testing and replacing sensors means opening the casing, so this is engineer-only.",
   "engineer_after_one_reset": true,
   "page_url": "https://combicert.co.uk/boiler-fault-codes/viessmann/#viessmann-38",
   "source_manual": "Vitodens 100-W Type B1HA, B1KA Installation and Service Instructions; Vitodens 050-W Type BPJC Installation and Service Instructions",
   "source_doc": "5677 216 GB (3/2015); 5513 085 GB (9/2014)",
   "source_pages": "100-W pp. 62–65 'Fault display'; 050-W PDF pp. 46–49 'Fault display'",
   "source_url": "https://viessmanndirect.co.uk/files/461be7f2-8610-4b7f-a942-a9d1010d8602/Vitodens%20100-W%20B1HA%20B1KA%20Installation%20and%20Service%20Manual.pdf",
   "source_type": "trade-site mirror (no manufacturer-hosted copy found)"
  },
  {
   "id": "viessmann-50",
   "code": "50",
   "brand": "Viessmann",
   "model_range": "Vitodens 050-W (BPJC) and Vitodens 100-W (B1HA / B1KA)",
   "category": "Sensors / thermistors",
   "meaning": "Cylinder temperature sensor short circuit; no hot water heating (100-W manual).",
   "homeowner_action": "Write down the full code. Check the boiler has power, then switch it off and on at its mains switch or press reset once. If the code comes back, leave it there: sensors are inside the casing.",
   "when_to_call_engineer": "Call a Gas Safe registered engineer if the code returns. Testing and replacing sensors means opening the casing, so this is engineer-only.",
   "engineer_after_one_reset": true,
   "page_url": "https://combicert.co.uk/boiler-fault-codes/viessmann/#viessmann-50",
   "source_manual": "Vitodens 100-W Type B1HA, B1KA Installation and Service Instructions; Vitodens 050-W Type BPJC Installation and Service Instructions",
   "source_doc": "5677 216 GB (3/2015); 5513 085 GB (9/2014)",
   "source_pages": "100-W pp. 62–65 'Fault display'; 050-W PDF pp. 46–49 'Fault display'",
   "source_url": "https://viessmanndirect.co.uk/files/461be7f2-8610-4b7f-a942-a9d1010d8602/Vitodens%20100-W%20B1HA%20B1KA%20Installation%20and%20Service%20Manual.pdf",
   "source_type": "trade-site mirror (no manufacturer-hosted copy found)"
  },
  {
   "id": "viessmann-51",
   "code": "51",
   "brand": "Viessmann",
   "model_range": "Vitodens 050-W (BPJC) and Vitodens 100-W (B1HA / B1KA)",
   "category": "Sensors / thermistors",
   "meaning": "Hot water outlet temperature sensor short circuit; no hot water heating.",
   "homeowner_action": "Write down the full code. Check the boiler has power, then switch it off and on at its mains switch or press reset once. If the code comes back, leave it there: sensors are inside the casing.",
   "when_to_call_engineer": "Call a Gas Safe registered engineer if the code returns. Testing and replacing sensors means opening the casing, so this is engineer-only.",
   "engineer_after_one_reset": true,
   "page_url": "https://combicert.co.uk/boiler-fault-codes/viessmann/#viessmann-51",
   "source_manual": "Vitodens 100-W Type B1HA, B1KA Installation and Service Instructions; Vitodens 050-W Type BPJC Installation and Service Instructions",
   "source_doc": "5677 216 GB (3/2015); 5513 085 GB (9/2014)",
   "source_pages": "100-W pp. 62–65 'Fault display'; 050-W PDF pp. 46–49 'Fault display'",
   "source_url": "https://viessmanndirect.co.uk/files/461be7f2-8610-4b7f-a942-a9d1010d8602/Vitodens%20100-W%20B1HA%20B1KA%20Installation%20and%20Service%20Manual.pdf",
   "source_type": "trade-site mirror (no manufacturer-hosted copy found)"
  },
  {
   "id": "viessmann-52",
   "code": "52",
   "brand": "Viessmann",
   "model_range": "Vitodens 050-W (BPJC) and Vitodens 100-W (B1HA / B1KA)",
   "category": "Sensors / thermistors",
   "meaning": "Flow sensor short circuit. The burner is blocked.",
   "homeowner_action": "Write down the full code. Check the boiler has power, then switch it off and on at its mains switch or press reset once. If the code comes back, leave it there: sensors are inside the casing.",
   "when_to_call_engineer": "Call a Gas Safe registered engineer if the code returns. Testing and replacing sensors means opening the casing, so this is engineer-only.",
   "engineer_after_one_reset": true,
   "page_url": "https://combicert.co.uk/boiler-fault-codes/viessmann/#viessmann-52",
   "source_manual": "Vitodens 100-W Type B1HA, B1KA Installation and Service Instructions; Vitodens 050-W Type BPJC Installation and Service Instructions",
   "source_doc": "5677 216 GB (3/2015); 5513 085 GB (9/2014)",
   "source_pages": "100-W pp. 62–65 'Fault display'; 050-W PDF pp. 46–49 'Fault display'",
   "source_url": "https://viessmanndirect.co.uk/files/461be7f2-8610-4b7f-a942-a9d1010d8602/Vitodens%20100-W%20B1HA%20B1KA%20Installation%20and%20Service%20Manual.pdf",
   "source_type": "trade-site mirror (no manufacturer-hosted copy found)"
  },
  {
   "id": "viessmann-58",
   "code": "58",
   "brand": "Viessmann",
   "model_range": "Vitodens 050-W (BPJC) and Vitodens 100-W (B1HA / B1KA)",
   "category": "Sensors / thermistors",
   "meaning": "Cylinder temperature sensor lead break; no hot water heating (100-W manual).",
   "homeowner_action": "Write down the full code. Check the boiler has power, then switch it off and on at its mains switch or press reset once. If the code comes back, leave it there: sensors are inside the casing.",
   "when_to_call_engineer": "Call a Gas Safe registered engineer if the code returns. Testing and replacing sensors means opening the casing, so this is engineer-only.",
   "engineer_after_one_reset": true,
   "page_url": "https://combicert.co.uk/boiler-fault-codes/viessmann/#viessmann-58",
   "source_manual": "Vitodens 100-W Type B1HA, B1KA Installation and Service Instructions; Vitodens 050-W Type BPJC Installation and Service Instructions",
   "source_doc": "5677 216 GB (3/2015); 5513 085 GB (9/2014)",
   "source_pages": "100-W pp. 62–65 'Fault display'; 050-W PDF pp. 46–49 'Fault display'",
   "source_url": "https://viessmanndirect.co.uk/files/461be7f2-8610-4b7f-a942-a9d1010d8602/Vitodens%20100-W%20B1HA%20B1KA%20Installation%20and%20Service%20Manual.pdf",
   "source_type": "trade-site mirror (no manufacturer-hosted copy found)"
  },
  {
   "id": "viessmann-59",
   "code": "59",
   "brand": "Viessmann",
   "model_range": "Vitodens 050-W (BPJC) and Vitodens 100-W (B1HA / B1KA)",
   "category": "Sensors / thermistors",
   "meaning": "Hot water outlet temperature sensor lead break; no hot water heating.",
   "homeowner_action": "Write down the full code. Check the boiler has power, then switch it off and on at its mains switch or press reset once. If the code comes back, leave it there: sensors are inside the casing.",
   "when_to_call_engineer": "Call a Gas Safe registered engineer if the code returns. Testing and replacing sensors means opening the casing, so this is engineer-only.",
   "engineer_after_one_reset": true,
   "page_url": "https://combicert.co.uk/boiler-fault-codes/viessmann/#viessmann-59",
   "source_manual": "Vitodens 100-W Type B1HA, B1KA Installation and Service Instructions; Vitodens 050-W Type BPJC Installation and Service Instructions",
   "source_doc": "5677 216 GB (3/2015); 5513 085 GB (9/2014)",
   "source_pages": "100-W pp. 62–65 'Fault display'; 050-W PDF pp. 46–49 'Fault display'",
   "source_url": "https://viessmanndirect.co.uk/files/461be7f2-8610-4b7f-a942-a9d1010d8602/Vitodens%20100-W%20B1HA%20B1KA%20Installation%20and%20Service%20Manual.pdf",
   "source_type": "trade-site mirror (no manufacturer-hosted copy found)"
  },
  {
   "id": "viessmann-5a",
   "code": "5A",
   "brand": "Viessmann",
   "model_range": "Vitodens 050-W (BPJC) and Vitodens 100-W (B1HA / B1KA)",
   "category": "Sensors / thermistors",
   "meaning": "Flow sensor lead break. The burner is blocked.",
   "homeowner_action": "Write down the full code. Check the boiler has power, then switch it off and on at its mains switch or press reset once. If the code comes back, leave it there: sensors are inside the casing.",
   "when_to_call_engineer": "Call a Gas Safe registered engineer if the code returns. Testing and replacing sensors means opening the casing, so this is engineer-only.",
   "engineer_after_one_reset": true,
   "page_url": "https://combicert.co.uk/boiler-fault-codes/viessmann/#viessmann-5a",
   "source_manual": "Vitodens 100-W Type B1HA, B1KA Installation and Service Instructions; Vitodens 050-W Type BPJC Installation and Service Instructions",
   "source_doc": "5677 216 GB (3/2015); 5513 085 GB (9/2014)",
   "source_pages": "100-W pp. 62–65 'Fault display'; 050-W PDF pp. 46–49 'Fault display'",
   "source_url": "https://viessmanndirect.co.uk/files/461be7f2-8610-4b7f-a942-a9d1010d8602/Vitodens%20100-W%20B1HA%20B1KA%20Installation%20and%20Service%20Manual.pdf",
   "source_type": "trade-site mirror (no manufacturer-hosted copy found)"
  },
  {
   "id": "viessmann-b0",
   "code": "b0",
   "brand": "Viessmann",
   "model_range": "Vitodens 050-W (BPJC) and Vitodens 100-W (B1HA / B1KA)",
   "category": "Sensors / thermistors",
   "meaning": "Flue gas temperature sensor short circuit. The burner is blocked.",
   "homeowner_action": "Write down the full code. Check the boiler has power, then switch it off and on at its mains switch or press reset once. If the code comes back, leave it there: sensors are inside the casing.",
   "when_to_call_engineer": "Call a Gas Safe registered engineer if the code returns. Testing and replacing sensors means opening the casing, so this is engineer-only.",
   "engineer_after_one_reset": true,
   "page_url": "https://combicert.co.uk/boiler-fault-codes/viessmann/#viessmann-b0",
   "source_manual": "Vitodens 100-W Type B1HA, B1KA Installation and Service Instructions; Vitodens 050-W Type BPJC Installation and Service Instructions",
   "source_doc": "5677 216 GB (3/2015); 5513 085 GB (9/2014)",
   "source_pages": "100-W pp. 62–65 'Fault display'; 050-W PDF pp. 46–49 'Fault display'",
   "source_url": "https://viessmanndirect.co.uk/files/461be7f2-8610-4b7f-a942-a9d1010d8602/Vitodens%20100-W%20B1HA%20B1KA%20Installation%20and%20Service%20Manual.pdf",
   "source_type": "trade-site mirror (no manufacturer-hosted copy found)"
  },
  {
   "id": "viessmann-b8",
   "code": "b8",
   "brand": "Viessmann",
   "model_range": "Vitodens 050-W (BPJC) and Vitodens 100-W (B1HA / B1KA)",
   "category": "Sensors / thermistors",
   "meaning": "Flue gas temperature sensor lead break. The burner is blocked.",
   "homeowner_action": "Write down the full code. Check the boiler has power, then switch it off and on at its mains switch or press reset once. If the code comes back, leave it there: sensors are inside the casing.",
   "when_to_call_engineer": "Call a Gas Safe registered engineer if the code returns. Testing and replacing sensors means opening the casing, so this is engineer-only.",
   "engineer_after_one_reset": true,
   "page_url": "https://combicert.co.uk/boiler-fault-codes/viessmann/#viessmann-b8",
   "source_manual": "Vitodens 100-W Type B1HA, B1KA Installation and Service Instructions; Vitodens 050-W Type BPJC Installation and Service Instructions",
   "source_doc": "5677 216 GB (3/2015); 5513 085 GB (9/2014)",
   "source_pages": "100-W pp. 62–65 'Fault display'; 050-W PDF pp. 46–49 'Fault display'",
   "source_url": "https://viessmanndirect.co.uk/files/461be7f2-8610-4b7f-a942-a9d1010d8602/Vitodens%20100-W%20B1HA%20B1KA%20Installation%20and%20Service%20Manual.pdf",
   "source_type": "trade-site mirror (no manufacturer-hosted copy found)"
  },
  {
   "id": "viessmann-f0",
   "code": "F0",
   "brand": "Viessmann",
   "model_range": "Vitodens 050-W (BPJC) and Vitodens 100-W (B1HA / B1KA)",
   "category": "PCB / electrical",
   "meaning": "Internal fault; the burner is blocked.",
   "homeowner_action": "Write down the full code. Check the boiler has power and nothing else in the house has tripped, then switch the boiler off and on at its mains switch or press reset once. If the code comes back, leave the boiler off.",
   "when_to_call_engineer": "Call a Gas Safe registered engineer if the code returns. Board, wiring and gas valve checks mean opening the casing, so this is engineer-only.",
   "engineer_after_one_reset": true,
   "page_url": "https://combicert.co.uk/boiler-fault-codes/viessmann/#viessmann-f0",
   "source_manual": "Vitodens 100-W Type B1HA, B1KA Installation and Service Instructions; Vitodens 050-W Type BPJC Installation and Service Instructions",
   "source_doc": "5677 216 GB (3/2015); 5513 085 GB (9/2014)",
   "source_pages": "100-W pp. 62–65 'Fault display'; 050-W PDF pp. 46–49 'Fault display'",
   "source_url": "https://viessmanndirect.co.uk/files/461be7f2-8610-4b7f-a942-a9d1010d8602/Vitodens%20100-W%20B1HA%20B1KA%20Installation%20and%20Service%20Manual.pdf",
   "source_type": "trade-site mirror (no manufacturer-hosted copy found)"
  },
  {
   "id": "viessmann-fd",
   "code": "Fd",
   "brand": "Viessmann",
   "model_range": "Vitodens 050-W (BPJC) and Vitodens 100-W (B1HA / B1KA)",
   "category": "PCB / electrical",
   "meaning": "Burner control unit fault.",
   "homeowner_action": "Write down the full code. Check the boiler has power and nothing else in the house has tripped, then switch the boiler off and on at its mains switch or press reset once. If the code comes back, leave the boiler off.",
   "when_to_call_engineer": "Call a Gas Safe registered engineer if the code returns. Board, wiring and gas valve checks mean opening the casing, so this is engineer-only.",
   "engineer_after_one_reset": true,
   "page_url": "https://combicert.co.uk/boiler-fault-codes/viessmann/#viessmann-fd",
   "source_manual": "Vitodens 100-W Type B1HA, B1KA Installation and Service Instructions; Vitodens 050-W Type BPJC Installation and Service Instructions",
   "source_doc": "5677 216 GB (3/2015); 5513 085 GB (9/2014)",
   "source_pages": "100-W pp. 62–65 'Fault display'; 050-W PDF pp. 46–49 'Fault display'",
   "source_url": "https://viessmanndirect.co.uk/files/461be7f2-8610-4b7f-a942-a9d1010d8602/Vitodens%20100-W%20B1HA%20B1KA%20Installation%20and%20Service%20Manual.pdf",
   "source_type": "trade-site mirror (no manufacturer-hosted copy found)"
  },
  {
   "id": "viessmann-ff",
   "code": "FF",
   "brand": "Viessmann",
   "model_range": "Vitodens 050-W (BPJC) and Vitodens 100-W (B1HA / B1KA)",
   "category": "PCB / electrical",
   "meaning": "Burner control unit fault.",
   "homeowner_action": "Write down the full code. Check the boiler has power and nothing else in the house has tripped, then switch the boiler off and on at its mains switch or press reset once. If the code comes back, leave the boiler off.",
   "when_to_call_engineer": "Call a Gas Safe registered engineer if the code returns. Board, wiring and gas valve checks mean opening the casing, so this is engineer-only.",
   "engineer_after_one_reset": true,
   "page_url": "https://combicert.co.uk/boiler-fault-codes/viessmann/#viessmann-ff",
   "source_manual": "Vitodens 100-W Type B1HA, B1KA Installation and Service Instructions; Vitodens 050-W Type BPJC Installation and Service Instructions",
   "source_doc": "5677 216 GB (3/2015); 5513 085 GB (9/2014)",
   "source_pages": "100-W pp. 62–65 'Fault display'; 050-W PDF pp. 46–49 'Fault display'",
   "source_url": "https://viessmanndirect.co.uk/files/461be7f2-8610-4b7f-a942-a9d1010d8602/Vitodens%20100-W%20B1HA%20B1KA%20Installation%20and%20Service%20Manual.pdf",
   "source_type": "trade-site mirror (no manufacturer-hosted copy found)"
  },
  {
   "id": "viessmann-a9",
   "code": "A9",
   "brand": "Viessmann",
   "model_range": "Vitodens 050-W (BPJC) and Vitodens 100-W (B1HA / B1KA)",
   "category": "Other / controls",
   "meaning": "Communication error with an OpenTherm control; the boiler runs without it.",
   "homeowner_action": "Check your room thermostat or programmer has power or fresh batteries and is set to call for heat. For a wireless control, follow its guide to reconnect it. Then press reset once.",
   "when_to_call_engineer": "Call a Gas Safe registered engineer if the code stays after you have checked the controls, or keeps coming back.",
   "engineer_after_one_reset": false,
   "page_url": "https://combicert.co.uk/boiler-fault-codes/viessmann/#viessmann-a9",
   "source_manual": "Vitodens 100-W Type B1HA, B1KA Installation and Service Instructions; Vitodens 050-W Type BPJC Installation and Service Instructions",
   "source_doc": "5677 216 GB (3/2015); 5513 085 GB (9/2014)",
   "source_pages": "100-W pp. 62–65 'Fault display'; 050-W PDF pp. 46–49 'Fault display'",
   "source_url": "https://viessmanndirect.co.uk/files/461be7f2-8610-4b7f-a942-a9d1010d8602/Vitodens%20100-W%20B1HA%20B1KA%20Installation%20and%20Service%20Manual.pdf",
   "source_type": "trade-site mirror (no manufacturer-hosted copy found)"
  },
  {
   "id": "vaillant-f26",
   "code": "F.26",
   "brand": "Vaillant",
   "model_range": "ecoTEC plus (VU / VUW ..6/5-5, combi and system)",
   "category": "Ignition / flame",
   "meaning": "Fault: the gas valve stepper motor is not working or not connected.",
   "homeowner_action": "There is no homeowner check that fixes this code. Write down the full code, press reset once, and if it comes back leave the boiler off.",
   "when_to_call_engineer": "Call a Gas Safe registered engineer if the code comes back after one reset. Ignition and flame faults involve gas, so this is engineer-only.",
   "engineer_after_one_reset": true,
   "page_url": "https://combicert.co.uk/boiler-fault-codes/vaillant/#vaillant-f26",
   "source_manual": "ecoTEC plus Installation and Maintenance Instructions (VU, VUW ..6/5-5)",
   "source_doc": "0020244997_07 (15.07.2021)",
   "source_pages": "pp. 60–62, Appendix E Overview of fault codes",
   "source_url": "https://professional.vaillant.co.uk/downloads/product-manuals/ecotec-plus-1/ecotec-plus-combi-and-system-installation-instructions-2422739.pdf",
   "source_type": "manufacturer"
  },
  {
   "id": "vaillant-f27",
   "code": "F.27",
   "brand": "Vaillant",
   "model_range": "ecoTEC plus (VU / VUW ..6/5-5, combi and system)",
   "category": "Ignition / flame",
   "meaning": "Safety shut-down: flame simulation. The flame sensor reports a flame that should not be there.",
   "homeowner_action": "There is no homeowner check that fixes this code. Write down the full code, press reset once, and if it comes back leave the boiler off.",
   "when_to_call_engineer": "Call a Gas Safe registered engineer if the code comes back after one reset. Ignition and flame faults involve gas, so this is engineer-only.",
   "engineer_after_one_reset": true,
   "page_url": "https://combicert.co.uk/boiler-fault-codes/vaillant/#vaillant-f27",
   "source_manual": "ecoTEC plus Installation and Maintenance Instructions (VU, VUW ..6/5-5)",
   "source_doc": "0020244997_07 (15.07.2021)",
   "source_pages": "pp. 60–62, Appendix E Overview of fault codes",
   "source_url": "https://professional.vaillant.co.uk/downloads/product-manuals/ecotec-plus-1/ecotec-plus-combi-and-system-installation-instructions-2422739.pdf",
   "source_type": "manufacturer"
  },
  {
   "id": "vaillant-f28",
   "code": "F.28",
   "brand": "Vaillant",
   "model_range": "ecoTEC plus (VU / VUW ..6/5-5, combi and system)",
   "category": "Ignition / flame",
   "meaning": "Start-up failure: ignition unsuccessful.",
   "homeowner_action": "There is no homeowner check that fixes this code. Write down the full code, press reset once, and if it comes back leave the boiler off.",
   "when_to_call_engineer": "Call a Gas Safe registered engineer if the code comes back after one reset. Ignition and flame faults involve gas, so this is engineer-only.",
   "engineer_after_one_reset": true,
   "page_url": "https://combicert.co.uk/boiler-fault-codes/vaillant/#vaillant-f28",
   "source_manual": "ecoTEC plus Installation and Maintenance Instructions (VU, VUW ..6/5-5)",
   "source_doc": "0020244997_07 (15.07.2021)",
   "source_pages": "pp. 60–62, Appendix E Overview of fault codes",
   "source_url": "https://professional.vaillant.co.uk/downloads/product-manuals/ecotec-plus-1/ecotec-plus-combi-and-system-installation-instructions-2422739.pdf",
   "source_type": "manufacturer"
  },
  {
   "id": "vaillant-f29",
   "code": "F.29",
   "brand": "Vaillant",
   "model_range": "ecoTEC plus (VU / VUW ..6/5-5, combi and system)",
   "category": "Ignition / flame",
   "meaning": "Operating failure: the flame went out and re-ignition failed.",
   "homeowner_action": "There is no homeowner check that fixes this code. Write down the full code, press reset once, and if it comes back leave the boiler off.",
   "when_to_call_engineer": "Call a Gas Safe registered engineer if the code comes back after one reset. Ignition and flame faults involve gas, so this is engineer-only.",
   "engineer_after_one_reset": true,
   "page_url": "https://combicert.co.uk/boiler-fault-codes/vaillant/#vaillant-f29",
   "source_manual": "ecoTEC plus Installation and Maintenance Instructions (VU, VUW ..6/5-5)",
   "source_doc": "0020244997_07 (15.07.2021)",
   "source_pages": "pp. 60–62, Appendix E Overview of fault codes",
   "source_url": "https://professional.vaillant.co.uk/downloads/product-manuals/ecotec-plus-1/ecotec-plus-combi-and-system-installation-instructions-2422739.pdf",
   "source_type": "manufacturer"
  },
  {
   "id": "vaillant-f54",
   "code": "F.54",
   "brand": "Vaillant",
   "model_range": "ecoTEC plus (VU / VUW ..6/5-5, combi and system)",
   "category": "Ignition / flame",
   "meaning": "Fault at boiler start: no or insufficient gas inlet pressure.",
   "homeowner_action": "Check another gas appliance such as the hob works, the gas meter valve is on and, on a prepayment meter, there is credit. In freezing weather, check the plastic condensate pipe outside: if it is frozen, pour warm (not boiling) water along it. Then press reset once. If the code comes back, stop resetting.",
   "when_to_call_engineer": "Call a Gas Safe registered engineer if the gas supply is fine and the code returns after one reset. Ignition and flame faults involve gas, so this is engineer-only.",
   "engineer_after_one_reset": false,
   "page_url": "https://combicert.co.uk/boiler-fault-codes/vaillant/#vaillant-f54",
   "source_manual": "ecoTEC plus Installation and Maintenance Instructions (VU, VUW ..6/5-5)",
   "source_doc": "0020244997_07 (15.07.2021)",
   "source_pages": "pp. 60–62, Appendix E Overview of fault codes",
   "source_url": "https://professional.vaillant.co.uk/downloads/product-manuals/ecotec-plus-1/ecotec-plus-combi-and-system-installation-instructions-2422739.pdf",
   "source_type": "manufacturer"
  },
  {
   "id": "vaillant-f61",
   "code": "F.61",
   "brand": "Vaillant",
   "model_range": "ecoTEC plus (VU / VUW ..6/5-5, combi and system)",
   "category": "Ignition / flame",
   "meaning": "Fault: the gas valve cannot be actuated.",
   "homeowner_action": "There is no homeowner check that fixes this code. Write down the full code, press reset once, and if it comes back leave the boiler off.",
   "when_to_call_engineer": "Call a Gas Safe registered engineer if the code comes back after one reset. Ignition and flame faults involve gas, so this is engineer-only.",
   "engineer_after_one_reset": true,
   "page_url": "https://combicert.co.uk/boiler-fault-codes/vaillant/#vaillant-f61",
   "source_manual": "ecoTEC plus Installation and Maintenance Instructions (VU, VUW ..6/5-5)",
   "source_doc": "0020244997_07 (15.07.2021)",
   "source_pages": "pp. 60–62, Appendix E Overview of fault codes",
   "source_url": "https://professional.vaillant.co.uk/downloads/product-manuals/ecotec-plus-1/ecotec-plus-combi-and-system-installation-instructions-2422739.pdf",
   "source_type": "manufacturer"
  },
  {
   "id": "vaillant-f62",
   "code": "F.62",
   "brand": "Vaillant",
   "model_range": "ecoTEC plus (VU / VUW ..6/5-5, combi and system)",
   "category": "Ignition / flame",
   "meaning": "Fault: the gas valve is slow to shut off after the flame goes out.",
   "homeowner_action": "There is no homeowner check that fixes this code. Write down the full code, press reset once, and if it comes back leave the boiler off.",
   "when_to_call_engineer": "Call a Gas Safe registered engineer if the code comes back after one reset. Ignition and flame faults involve gas, so this is engineer-only.",
   "engineer_after_one_reset": true,
   "page_url": "https://combicert.co.uk/boiler-fault-codes/vaillant/#vaillant-f62",
   "source_manual": "ecoTEC plus Installation and Maintenance Instructions (VU, VUW ..6/5-5)",
   "source_doc": "0020244997_07 (15.07.2021)",
   "source_pages": "pp. 60–62, Appendix E Overview of fault codes",
   "source_url": "https://professional.vaillant.co.uk/downloads/product-manuals/ecotec-plus-1/ecotec-plus-combi-and-system-installation-instructions-2422739.pdf",
   "source_type": "manufacturer"
  },
  {
   "id": "vaillant-f67",
   "code": "F.67",
   "brand": "Vaillant",
   "model_range": "ecoTEC plus (VU / VUW ..6/5-5, combi and system)",
   "category": "Ignition / flame",
   "meaning": "Implausible flame signal.",
   "homeowner_action": "There is no homeowner check that fixes this code. Write down the full code, press reset once, and if it comes back leave the boiler off.",
   "when_to_call_engineer": "Call a Gas Safe registered engineer if the code comes back after one reset. Ignition and flame faults involve gas, so this is engineer-only.",
   "engineer_after_one_reset": true,
   "page_url": "https://combicert.co.uk/boiler-fault-codes/vaillant/#vaillant-f67",
   "source_manual": "ecoTEC plus Installation and Maintenance Instructions (VU, VUW ..6/5-5)",
   "source_doc": "0020244997_07 (15.07.2021)",
   "source_pages": "pp. 60–62, Appendix E Overview of fault codes",
   "source_url": "https://professional.vaillant.co.uk/downloads/product-manuals/ecotec-plus-1/ecotec-plus-combi-and-system-installation-instructions-2422739.pdf",
   "source_type": "manufacturer"
  },
  {
   "id": "vaillant-f68",
   "code": "F.68",
   "brand": "Vaillant",
   "model_range": "ecoTEC plus (VU / VUW ..6/5-5, combi and system)",
   "category": "Ignition / flame",
   "meaning": "Unstable flame signal.",
   "homeowner_action": "There is no homeowner check that fixes this code. Write down the full code, press reset once, and if it comes back leave the boiler off.",
   "when_to_call_engineer": "Call a Gas Safe registered engineer if the code comes back after one reset. Ignition and flame faults involve gas, so this is engineer-only.",
   "engineer_after_one_reset": true,
   "page_url": "https://combicert.co.uk/boiler-fault-codes/vaillant/#vaillant-f68",
   "source_manual": "ecoTEC plus Installation and Maintenance Instructions (VU, VUW ..6/5-5)",
   "source_doc": "0020244997_07 (15.07.2021)",
   "source_pages": "pp. 60–62, Appendix E Overview of fault codes",
   "source_url": "https://professional.vaillant.co.uk/downloads/product-manuals/ecotec-plus-1/ecotec-plus-combi-and-system-installation-instructions-2422739.pdf",
   "source_type": "manufacturer"
  },
  {
   "id": "vaillant-f92",
   "code": "F.92",
   "brand": "Vaillant",
   "model_range": "ecoTEC plus (VU / VUW ..6/5-5, combi and system)",
   "category": "Ignition / flame",
   "meaning": "Incorrect gas type: the coding resistor does not match the gas group entered.",
   "homeowner_action": "There is no homeowner check that fixes this code. Write down the full code, press reset once, and if it comes back leave the boiler off.",
   "when_to_call_engineer": "Call a Gas Safe registered engineer if the code comes back after one reset. Ignition and flame faults involve gas, so this is engineer-only.",
   "engineer_after_one_reset": true,
   "page_url": "https://combicert.co.uk/boiler-fault-codes/vaillant/#vaillant-f92",
   "source_manual": "ecoTEC plus Installation and Maintenance Instructions (VU, VUW ..6/5-5)",
   "source_doc": "0020244997_07 (15.07.2021)",
   "source_pages": "pp. 60–62, Appendix E Overview of fault codes",
   "source_url": "https://professional.vaillant.co.uk/downloads/product-manuals/ecotec-plus-1/ecotec-plus-combi-and-system-installation-instructions-2422739.pdf",
   "source_type": "manufacturer"
  },
  {
   "id": "vaillant-f93",
   "code": "F.93",
   "brand": "Vaillant",
   "model_range": "ecoTEC plus (VU / VUW ..6/5-5, combi and system)",
   "category": "Ignition / flame",
   "meaning": "Combustion quality outside the permitted range.",
   "homeowner_action": "There is no homeowner check that fixes this code. Write down the full code, press reset once, and if it comes back leave the boiler off.",
   "when_to_call_engineer": "Call a Gas Safe registered engineer if the code comes back after one reset. Ignition and flame faults involve gas, so this is engineer-only.",
   "engineer_after_one_reset": true,
   "page_url": "https://combicert.co.uk/boiler-fault-codes/vaillant/#vaillant-f93",
   "source_manual": "ecoTEC plus Installation and Maintenance Instructions (VU, VUW ..6/5-5)",
   "source_doc": "0020244997_07 (15.07.2021)",
   "source_pages": "pp. 60–62, Appendix E Overview of fault codes",
   "source_url": "https://professional.vaillant.co.uk/downloads/product-manuals/ecotec-plus-1/ecotec-plus-combi-and-system-installation-instructions-2422739.pdf",
   "source_type": "manufacturer"
  },
  {
   "id": "vaillant-f22",
   "code": "F.22",
   "brand": "Vaillant",
   "model_range": "ecoTEC plus (VU / VUW ..6/5-5, combi and system)",
   "category": "Water pressure / circulation",
   "meaning": "Safety shut-down: low water pressure.",
   "homeowner_action": "Look at the pressure gauge while the boiler is cold. If it is below about 1 bar, top it up with the filling loop exactly as your user guide shows, to about 1–1.5 bar or the figure in your guide, then close the loop fully. Check the radiator valves are open, then press reset once.",
   "when_to_call_engineer": "Call a Gas Safe registered engineer if you have to top up more than once every few months, the gauge goes above about 2.5 bar when hot, water drips from the outside overflow pipe, or the code returns after topping up.",
   "engineer_after_one_reset": false,
   "page_url": "https://combicert.co.uk/boiler-fault-codes/vaillant/#vaillant-f22",
   "source_manual": "ecoTEC plus Installation and Maintenance Instructions (VU, VUW ..6/5-5)",
   "source_doc": "0020244997_07 (15.07.2021)",
   "source_pages": "pp. 60–62, Appendix E Overview of fault codes",
   "source_url": "https://professional.vaillant.co.uk/downloads/product-manuals/ecotec-plus-1/ecotec-plus-combi-and-system-installation-instructions-2422739.pdf",
   "source_type": "manufacturer"
  },
  {
   "id": "vaillant-f23",
   "code": "F.23",
   "brand": "Vaillant",
   "model_range": "ecoTEC plus (VU / VUW ..6/5-5, combi and system)",
   "category": "Water pressure / circulation",
   "meaning": "Safety shut-down: the flow/return temperature difference is too large (water circulation too low).",
   "homeowner_action": "There is no homeowner check that fixes this code. Write down the full code, press reset once, and if it comes back leave the boiler off.",
   "when_to_call_engineer": "Call a Gas Safe registered engineer if you have to top up more than once every few months, the gauge goes above about 2.5 bar when hot, water drips from the outside overflow pipe, or the code returns after topping up.",
   "engineer_after_one_reset": true,
   "page_url": "https://combicert.co.uk/boiler-fault-codes/vaillant/#vaillant-f23",
   "source_manual": "ecoTEC plus Installation and Maintenance Instructions (VU, VUW ..6/5-5)",
   "source_doc": "0020244997_07 (15.07.2021)",
   "source_pages": "pp. 60–62, Appendix E Overview of fault codes",
   "source_url": "https://professional.vaillant.co.uk/downloads/product-manuals/ecotec-plus-1/ecotec-plus-combi-and-system-installation-instructions-2422739.pdf",
   "source_type": "manufacturer"
  },
  {
   "id": "vaillant-f73",
   "code": "F.73",
   "brand": "Vaillant",
   "model_range": "ecoTEC plus (VU / VUW ..6/5-5, combi and system)",
   "category": "Water pressure / circulation",
   "meaning": "The water pressure sensor reports the pressure as too low (signal too weak).",
   "homeowner_action": "Look at the pressure gauge while the boiler is cold. If it is below about 1 bar, top it up with the filling loop exactly as your user guide shows, to about 1–1.5 bar or the figure in your guide, then close the loop fully. Check the radiator valves are open, then press reset once.",
   "when_to_call_engineer": "Call a Gas Safe registered engineer if you have to top up more than once every few months, the gauge goes above about 2.5 bar when hot, water drips from the outside overflow pipe, or the code returns after topping up.",
   "engineer_after_one_reset": false,
   "page_url": "https://combicert.co.uk/boiler-fault-codes/vaillant/#vaillant-f73",
   "source_manual": "ecoTEC plus Installation and Maintenance Instructions (VU, VUW ..6/5-5)",
   "source_doc": "0020244997_07 (15.07.2021)",
   "source_pages": "pp. 60–62, Appendix E Overview of fault codes",
   "source_url": "https://professional.vaillant.co.uk/downloads/product-manuals/ecotec-plus-1/ecotec-plus-combi-and-system-installation-instructions-2422739.pdf",
   "source_type": "manufacturer"
  },
  {
   "id": "vaillant-f74",
   "code": "F.74",
   "brand": "Vaillant",
   "model_range": "ecoTEC plus (VU / VUW ..6/5-5, combi and system)",
   "category": "Water pressure / circulation",
   "meaning": "The water pressure is too high (sensor signal too strong).",
   "homeowner_action": "Read the gauge. If it is above about 2.5 bar, check the filling loop is fully closed. Do not try to release water from the boiler yourself.",
   "when_to_call_engineer": "Call a Gas Safe registered engineer if the pressure stays high or the code returns: an overfilled system, a letting-by filling loop or a faulty sensor need checking.",
   "engineer_after_one_reset": true,
   "page_url": "https://combicert.co.uk/boiler-fault-codes/vaillant/#vaillant-f74",
   "source_manual": "ecoTEC plus Installation and Maintenance Instructions (VU, VUW ..6/5-5)",
   "source_doc": "0020244997_07 (15.07.2021)",
   "source_pages": "pp. 60–62, Appendix E Overview of fault codes",
   "source_url": "https://professional.vaillant.co.uk/downloads/product-manuals/ecotec-plus-1/ecotec-plus-combi-and-system-installation-instructions-2422739.pdf",
   "source_type": "manufacturer"
  },
  {
   "id": "vaillant-f75",
   "code": "F.75",
   "brand": "Vaillant",
   "model_range": "ecoTEC plus (VU / VUW ..6/5-5, combi and system)",
   "category": "Water pressure / circulation",
   "meaning": "Pump or water shortage: no pressure rise detected when the pump starts.",
   "homeowner_action": "Look at the pressure gauge while the boiler is cold. If it is below about 1 bar, top it up with the filling loop exactly as your user guide shows, to about 1–1.5 bar or the figure in your guide, then close the loop fully. Check the radiator valves are open, then press reset once.",
   "when_to_call_engineer": "Call a Gas Safe registered engineer if you have to top up more than once every few months, the gauge goes above about 2.5 bar when hot, water drips from the outside overflow pipe, or the code returns after topping up.",
   "engineer_after_one_reset": false,
   "page_url": "https://combicert.co.uk/boiler-fault-codes/vaillant/#vaillant-f75",
   "source_manual": "ecoTEC plus Installation and Maintenance Instructions (VU, VUW ..6/5-5)",
   "source_doc": "0020244997_07 (15.07.2021)",
   "source_pages": "pp. 60–62, Appendix E Overview of fault codes",
   "source_url": "https://professional.vaillant.co.uk/downloads/product-manuals/ecotec-plus-1/ecotec-plus-combi-and-system-installation-instructions-2422739.pdf",
   "source_type": "manufacturer"
  },
  {
   "id": "vaillant-f83",
   "code": "F.83",
   "brand": "Vaillant",
   "model_range": "ecoTEC plus (VU / VUW ..6/5-5, combi and system)",
   "category": "Water pressure / circulation",
   "meaning": "NTC temperature gradient fault: the flow and return barely changed when the burner fired.",
   "homeowner_action": "There is no homeowner check that fixes this code. Write down the full code, press reset once, and if it comes back leave the boiler off.",
   "when_to_call_engineer": "Call a Gas Safe registered engineer if you have to top up more than once every few months, the gauge goes above about 2.5 bar when hot, water drips from the outside overflow pipe, or the code returns after topping up.",
   "engineer_after_one_reset": true,
   "page_url": "https://combicert.co.uk/boiler-fault-codes/vaillant/#vaillant-f83",
   "source_manual": "ecoTEC plus Installation and Maintenance Instructions (VU, VUW ..6/5-5)",
   "source_doc": "0020244997_07 (15.07.2021)",
   "source_pages": "pp. 60–62, Appendix E Overview of fault codes",
   "source_url": "https://professional.vaillant.co.uk/downloads/product-manuals/ecotec-plus-1/ecotec-plus-combi-and-system-installation-instructions-2422739.pdf",
   "source_type": "manufacturer"
  },
  {
   "id": "vaillant-f20",
   "code": "F.20",
   "brand": "Vaillant",
   "model_range": "ecoTEC plus (VU / VUW ..6/5-5, combi and system)",
   "category": "Temperature / overheat",
   "meaning": "Safety shut-down: the temperature limiter acted because the flow or return temperature got too high.",
   "homeowner_action": "Let the boiler cool for 20 to 30 minutes, then press reset once. If the code comes back, leave the boiler off.",
   "when_to_call_engineer": "Call a Gas Safe registered engineer if the code comes back after one reset. Overheat shut-downs are safety devices doing their job, so this is engineer-only.",
   "engineer_after_one_reset": true,
   "page_url": "https://combicert.co.uk/boiler-fault-codes/vaillant/#vaillant-f20",
   "source_manual": "ecoTEC plus Installation and Maintenance Instructions (VU, VUW ..6/5-5)",
   "source_doc": "0020244997_07 (15.07.2021)",
   "source_pages": "pp. 60–62, Appendix E Overview of fault codes",
   "source_url": "https://professional.vaillant.co.uk/downloads/product-manuals/ecotec-plus-1/ecotec-plus-combi-and-system-installation-instructions-2422739.pdf",
   "source_type": "manufacturer"
  },
  {
   "id": "vaillant-f24",
   "code": "F.24",
   "brand": "Vaillant",
   "model_range": "ecoTEC plus (VU / VUW ..6/5-5, combi and system)",
   "category": "Temperature / overheat",
   "meaning": "Safety shut-down: the temperature is rising too fast.",
   "homeowner_action": "Let the boiler cool for 20 to 30 minutes, then press reset once. If the code comes back, leave the boiler off.",
   "when_to_call_engineer": "Call a Gas Safe registered engineer if the code comes back after one reset. Overheat shut-downs are safety devices doing their job, so this is engineer-only.",
   "engineer_after_one_reset": true,
   "page_url": "https://combicert.co.uk/boiler-fault-codes/vaillant/#vaillant-f24",
   "source_manual": "ecoTEC plus Installation and Maintenance Instructions (VU, VUW ..6/5-5)",
   "source_doc": "0020244997_07 (15.07.2021)",
   "source_pages": "pp. 60–62, Appendix E Overview of fault codes",
   "source_url": "https://professional.vaillant.co.uk/downloads/product-manuals/ecotec-plus-1/ecotec-plus-combi-and-system-installation-instructions-2422739.pdf",
   "source_type": "manufacturer"
  },
  {
   "id": "vaillant-f25",
   "code": "F.25",
   "brand": "Vaillant",
   "model_range": "ecoTEC plus (VU / VUW ..6/5-5, combi and system)",
   "category": "Flue / fan / air",
   "meaning": "Safety shut-down: flue gas temperature too high.",
   "homeowner_action": "There is no homeowner check that fixes this code. Write down the full code, press reset once, and if it comes back leave the boiler off.",
   "when_to_call_engineer": "Call a Gas Safe registered engineer if the terminal looks clear and the code returns. Flue and fan faults can affect how combustion gases leave your home, so this is engineer-only.",
   "engineer_after_one_reset": true,
   "page_url": "https://combicert.co.uk/boiler-fault-codes/vaillant/#vaillant-f25",
   "source_manual": "ecoTEC plus Installation and Maintenance Instructions (VU, VUW ..6/5-5)",
   "source_doc": "0020244997_07 (15.07.2021)",
   "source_pages": "pp. 60–62, Appendix E Overview of fault codes",
   "source_url": "https://professional.vaillant.co.uk/downloads/product-manuals/ecotec-plus-1/ecotec-plus-combi-and-system-installation-instructions-2422739.pdf",
   "source_type": "manufacturer"
  },
  {
   "id": "vaillant-f32",
   "code": "F.32",
   "brand": "Vaillant",
   "model_range": "ecoTEC plus (VU / VUW ..6/5-5, combi and system)",
   "category": "Flue / fan / air",
   "meaning": "Fan fault: the fan is faulty or not connected.",
   "homeowner_action": "There is no homeowner check that fixes this code. Write down the full code, press reset once, and if it comes back leave the boiler off.",
   "when_to_call_engineer": "Call a Gas Safe registered engineer if the terminal looks clear and the code returns. Flue and fan faults can affect how combustion gases leave your home, so this is engineer-only.",
   "engineer_after_one_reset": true,
   "page_url": "https://combicert.co.uk/boiler-fault-codes/vaillant/#vaillant-f32",
   "source_manual": "ecoTEC plus Installation and Maintenance Instructions (VU, VUW ..6/5-5)",
   "source_doc": "0020244997_07 (15.07.2021)",
   "source_pages": "pp. 60–62, Appendix E Overview of fault codes",
   "source_url": "https://professional.vaillant.co.uk/downloads/product-manuals/ecotec-plus-1/ecotec-plus-combi-and-system-installation-instructions-2422739.pdf",
   "source_type": "manufacturer"
  },
  {
   "id": "vaillant-f00",
   "code": "F.00",
   "brand": "Vaillant",
   "model_range": "ecoTEC plus (VU / VUW ..6/5-5, combi and system)",
   "category": "Sensors / thermistors",
   "meaning": "Flow temperature sensor interruption: the sensor is faulty or not connected.",
   "homeowner_action": "Write down the full code. Check the boiler has power, then switch it off and on at its mains switch or press reset once. If the code comes back, leave it there: sensors are inside the casing.",
   "when_to_call_engineer": "Call a Gas Safe registered engineer if the code returns. Testing and replacing sensors means opening the casing, so this is engineer-only.",
   "engineer_after_one_reset": true,
   "page_url": "https://combicert.co.uk/boiler-fault-codes/vaillant/#vaillant-f00",
   "source_manual": "ecoTEC plus Installation and Maintenance Instructions (VU, VUW ..6/5-5)",
   "source_doc": "0020244997_07 (15.07.2021)",
   "source_pages": "pp. 60–62, Appendix E Overview of fault codes",
   "source_url": "https://professional.vaillant.co.uk/downloads/product-manuals/ecotec-plus-1/ecotec-plus-combi-and-system-installation-instructions-2422739.pdf",
   "source_type": "manufacturer"
  },
  {
   "id": "vaillant-f01",
   "code": "F.01",
   "brand": "Vaillant",
   "model_range": "ecoTEC plus (VU / VUW ..6/5-5, combi and system)",
   "category": "Sensors / thermistors",
   "meaning": "Return temperature sensor interruption: the sensor is faulty or not connected.",
   "homeowner_action": "Write down the full code. Check the boiler has power, then switch it off and on at its mains switch or press reset once. If the code comes back, leave it there: sensors are inside the casing.",
   "when_to_call_engineer": "Call a Gas Safe registered engineer if the code returns. Testing and replacing sensors means opening the casing, so this is engineer-only.",
   "engineer_after_one_reset": true,
   "page_url": "https://combicert.co.uk/boiler-fault-codes/vaillant/#vaillant-f01",
   "source_manual": "ecoTEC plus Installation and Maintenance Instructions (VU, VUW ..6/5-5)",
   "source_doc": "0020244997_07 (15.07.2021)",
   "source_pages": "pp. 60–62, Appendix E Overview of fault codes",
   "source_url": "https://professional.vaillant.co.uk/downloads/product-manuals/ecotec-plus-1/ecotec-plus-combi-and-system-installation-instructions-2422739.pdf",
   "source_type": "manufacturer"
  },
  {
   "id": "vaillant-f10",
   "code": "F.10",
   "brand": "Vaillant",
   "model_range": "ecoTEC plus (VU / VUW ..6/5-5, combi and system)",
   "category": "Sensors / thermistors",
   "meaning": "Flow temperature sensor short circuit.",
   "homeowner_action": "Write down the full code. Check the boiler has power, then switch it off and on at its mains switch or press reset once. If the code comes back, leave it there: sensors are inside the casing.",
   "when_to_call_engineer": "Call a Gas Safe registered engineer if the code returns. Testing and replacing sensors means opening the casing, so this is engineer-only.",
   "engineer_after_one_reset": true,
   "page_url": "https://combicert.co.uk/boiler-fault-codes/vaillant/#vaillant-f10",
   "source_manual": "ecoTEC plus Installation and Maintenance Instructions (VU, VUW ..6/5-5)",
   "source_doc": "0020244997_07 (15.07.2021)",
   "source_pages": "pp. 60–62, Appendix E Overview of fault codes",
   "source_url": "https://professional.vaillant.co.uk/downloads/product-manuals/ecotec-plus-1/ecotec-plus-combi-and-system-installation-instructions-2422739.pdf",
   "source_type": "manufacturer"
  },
  {
   "id": "vaillant-f11",
   "code": "F.11",
   "brand": "Vaillant",
   "model_range": "ecoTEC plus (VU / VUW ..6/5-5, combi and system)",
   "category": "Sensors / thermistors",
   "meaning": "Return temperature sensor short circuit.",
   "homeowner_action": "Write down the full code. Check the boiler has power, then switch it off and on at its mains switch or press reset once. If the code comes back, leave it there: sensors are inside the casing.",
   "when_to_call_engineer": "Call a Gas Safe registered engineer if the code returns. Testing and replacing sensors means opening the casing, so this is engineer-only.",
   "engineer_after_one_reset": true,
   "page_url": "https://combicert.co.uk/boiler-fault-codes/vaillant/#vaillant-f11",
   "source_manual": "ecoTEC plus Installation and Maintenance Instructions (VU, VUW ..6/5-5)",
   "source_doc": "0020244997_07 (15.07.2021)",
   "source_pages": "pp. 60–62, Appendix E Overview of fault codes",
   "source_url": "https://professional.vaillant.co.uk/downloads/product-manuals/ecotec-plus-1/ecotec-plus-combi-and-system-installation-instructions-2422739.pdf",
   "source_type": "manufacturer"
  },
  {
   "id": "vaillant-f13",
   "code": "F.13",
   "brand": "Vaillant",
   "model_range": "ecoTEC plus (VU / VUW ..6/5-5, combi and system)",
   "category": "Sensors / thermistors",
   "meaning": "Cylinder or warm-start sensor short circuit.",
   "homeowner_action": "Write down the full code. Check the boiler has power, then switch it off and on at its mains switch or press reset once. If the code comes back, leave it there: sensors are inside the casing.",
   "when_to_call_engineer": "Call a Gas Safe registered engineer if the code returns. Testing and replacing sensors means opening the casing, so this is engineer-only.",
   "engineer_after_one_reset": true,
   "page_url": "https://combicert.co.uk/boiler-fault-codes/vaillant/#vaillant-f13",
   "source_manual": "ecoTEC plus Installation and Maintenance Instructions (VU, VUW ..6/5-5)",
   "source_doc": "0020244997_07 (15.07.2021)",
   "source_pages": "pp. 60–62, Appendix E Overview of fault codes",
   "source_url": "https://professional.vaillant.co.uk/downloads/product-manuals/ecotec-plus-1/ecotec-plus-combi-and-system-installation-instructions-2422739.pdf",
   "source_type": "manufacturer"
  },
  {
   "id": "vaillant-f71",
   "code": "F.71",
   "brand": "Vaillant",
   "model_range": "ecoTEC plus (VU / VUW ..6/5-5, combi and system)",
   "category": "Sensors / thermistors",
   "meaning": "The flow temperature sensor is returning implausible values.",
   "homeowner_action": "Write down the full code. Check the boiler has power, then switch it off and on at its mains switch or press reset once. If the code comes back, leave it there: sensors are inside the casing.",
   "when_to_call_engineer": "Call a Gas Safe registered engineer if the code returns. Testing and replacing sensors means opening the casing, so this is engineer-only.",
   "engineer_after_one_reset": true,
   "page_url": "https://combicert.co.uk/boiler-fault-codes/vaillant/#vaillant-f71",
   "source_manual": "ecoTEC plus Installation and Maintenance Instructions (VU, VUW ..6/5-5)",
   "source_doc": "0020244997_07 (15.07.2021)",
   "source_pages": "pp. 60–62, Appendix E Overview of fault codes",
   "source_url": "https://professional.vaillant.co.uk/downloads/product-manuals/ecotec-plus-1/ecotec-plus-combi-and-system-installation-instructions-2422739.pdf",
   "source_type": "manufacturer"
  },
  {
   "id": "vaillant-f72",
   "code": "F.72",
   "brand": "Vaillant",
   "model_range": "ecoTEC plus (VU / VUW ..6/5-5, combi and system)",
   "category": "Sensors / thermistors",
   "meaning": "The temperature difference between the flow and return sensors is too great.",
   "homeowner_action": "Write down the full code. Check the boiler has power, then switch it off and on at its mains switch or press reset once. If the code comes back, leave it there: sensors are inside the casing.",
   "when_to_call_engineer": "Call a Gas Safe registered engineer if the code returns. Testing and replacing sensors means opening the casing, so this is engineer-only.",
   "engineer_after_one_reset": true,
   "page_url": "https://combicert.co.uk/boiler-fault-codes/vaillant/#vaillant-f72",
   "source_manual": "ecoTEC plus Installation and Maintenance Instructions (VU, VUW ..6/5-5)",
   "source_doc": "0020244997_07 (15.07.2021)",
   "source_pages": "pp. 60–62, Appendix E Overview of fault codes",
   "source_url": "https://professional.vaillant.co.uk/downloads/product-manuals/ecotec-plus-1/ecotec-plus-combi-and-system-installation-instructions-2422739.pdf",
   "source_type": "manufacturer"
  },
  {
   "id": "vaillant-f85",
   "code": "F.85",
   "brand": "Vaillant",
   "model_range": "ecoTEC plus (VU / VUW ..6/5-5, combi and system)",
   "category": "Sensors / thermistors",
   "meaning": "Flow and return sensors fitted incorrectly.",
   "homeowner_action": "Write down the full code. Check the boiler has power, then switch it off and on at its mains switch or press reset once. If the code comes back, leave it there: sensors are inside the casing.",
   "when_to_call_engineer": "Call a Gas Safe registered engineer if the code returns. Testing and replacing sensors means opening the casing, so this is engineer-only.",
   "engineer_after_one_reset": true,
   "page_url": "https://combicert.co.uk/boiler-fault-codes/vaillant/#vaillant-f85",
   "source_manual": "ecoTEC plus Installation and Maintenance Instructions (VU, VUW ..6/5-5)",
   "source_doc": "0020244997_07 (15.07.2021)",
   "source_pages": "pp. 60–62, Appendix E Overview of fault codes",
   "source_url": "https://professional.vaillant.co.uk/downloads/product-manuals/ecotec-plus-1/ecotec-plus-combi-and-system-installation-instructions-2422739.pdf",
   "source_type": "manufacturer"
  },
  {
   "id": "vaillant-f49",
   "code": "F.49",
   "brand": "Vaillant",
   "model_range": "ecoTEC plus (VU / VUW ..6/5-5, combi and system)",
   "category": "PCB / electrical",
   "meaning": "eBUS fault: under-voltage on the control bus.",
   "homeowner_action": "Write down the full code. Check the boiler has power and nothing else in the house has tripped, then switch the boiler off and on at its mains switch or press reset once. If the code comes back, leave the boiler off.",
   "when_to_call_engineer": "Call a Gas Safe registered engineer if the code returns. Board, wiring and gas valve checks mean opening the casing, so this is engineer-only.",
   "engineer_after_one_reset": true,
   "page_url": "https://combicert.co.uk/boiler-fault-codes/vaillant/#vaillant-f49",
   "source_manual": "ecoTEC plus Installation and Maintenance Instructions (VU, VUW ..6/5-5)",
   "source_doc": "0020244997_07 (15.07.2021)",
   "source_pages": "pp. 60–62, Appendix E Overview of fault codes",
   "source_url": "https://professional.vaillant.co.uk/downloads/product-manuals/ecotec-plus-1/ecotec-plus-combi-and-system-installation-instructions-2422739.pdf",
   "source_type": "manufacturer"
  },
  {
   "id": "vaillant-f63",
   "code": "F.63",
   "brand": "Vaillant",
   "model_range": "ecoTEC plus (VU / VUW ..6/5-5, combi and system)",
   "category": "PCB / electrical",
   "meaning": "EEPROM fault.",
   "homeowner_action": "Write down the full code. Check the boiler has power and nothing else in the house has tripped, then switch the boiler off and on at its mains switch or press reset once. If the code comes back, leave the boiler off.",
   "when_to_call_engineer": "Call a Gas Safe registered engineer if the code returns. Board, wiring and gas valve checks mean opening the casing, so this is engineer-only.",
   "engineer_after_one_reset": true,
   "page_url": "https://combicert.co.uk/boiler-fault-codes/vaillant/#vaillant-f63",
   "source_manual": "ecoTEC plus Installation and Maintenance Instructions (VU, VUW ..6/5-5)",
   "source_doc": "0020244997_07 (15.07.2021)",
   "source_pages": "pp. 60–62, Appendix E Overview of fault codes",
   "source_url": "https://professional.vaillant.co.uk/downloads/product-manuals/ecotec-plus-1/ecotec-plus-combi-and-system-installation-instructions-2422739.pdf",
   "source_type": "manufacturer"
  },
  {
   "id": "vaillant-f64",
   "code": "F.64",
   "brand": "Vaillant",
   "model_range": "ecoTEC plus (VU / VUW ..6/5-5, combi and system)",
   "category": "PCB / electrical",
   "meaning": "Electronics or safety-relevant sensor fault.",
   "homeowner_action": "Write down the full code. Check the boiler has power and nothing else in the house has tripped, then switch the boiler off and on at its mains switch or press reset once. If the code comes back, leave the boiler off.",
   "when_to_call_engineer": "Call a Gas Safe registered engineer if the code returns. Board, wiring and gas valve checks mean opening the casing, so this is engineer-only.",
   "engineer_after_one_reset": true,
   "page_url": "https://combicert.co.uk/boiler-fault-codes/vaillant/#vaillant-f64",
   "source_manual": "ecoTEC plus Installation and Maintenance Instructions (VU, VUW ..6/5-5)",
   "source_doc": "0020244997_07 (15.07.2021)",
   "source_pages": "pp. 60–62, Appendix E Overview of fault codes",
   "source_url": "https://professional.vaillant.co.uk/downloads/product-manuals/ecotec-plus-1/ecotec-plus-combi-and-system-installation-instructions-2422739.pdf",
   "source_type": "manufacturer"
  },
  {
   "id": "vaillant-f65",
   "code": "F.65",
   "brand": "Vaillant",
   "model_range": "ecoTEC plus (VU / VUW ..6/5-5, combi and system)",
   "category": "PCB / electrical",
   "meaning": "Electronics temperature fault: the electronics are faulty or too hot.",
   "homeowner_action": "Write down the full code. Check the boiler has power and nothing else in the house has tripped, then switch the boiler off and on at its mains switch or press reset once. If the code comes back, leave the boiler off.",
   "when_to_call_engineer": "Call a Gas Safe registered engineer if the code returns. Board, wiring and gas valve checks mean opening the casing, so this is engineer-only.",
   "engineer_after_one_reset": true,
   "page_url": "https://combicert.co.uk/boiler-fault-codes/vaillant/#vaillant-f65",
   "source_manual": "ecoTEC plus Installation and Maintenance Instructions (VU, VUW ..6/5-5)",
   "source_doc": "0020244997_07 (15.07.2021)",
   "source_pages": "pp. 60–62, Appendix E Overview of fault codes",
   "source_url": "https://professional.vaillant.co.uk/downloads/product-manuals/ecotec-plus-1/ecotec-plus-combi-and-system-installation-instructions-2422739.pdf",
   "source_type": "manufacturer"
  },
  {
   "id": "vaillant-f70",
   "code": "F.70",
   "brand": "Vaillant",
   "model_range": "ecoTEC plus (VU / VUW ..6/5-5, combi and system)",
   "category": "PCB / electrical",
   "meaning": "Invalid device specific number (DSN).",
   "homeowner_action": "Write down the full code. Check the boiler has power and nothing else in the house has tripped, then switch the boiler off and on at its mains switch or press reset once. If the code comes back, leave the boiler off.",
   "when_to_call_engineer": "Call a Gas Safe registered engineer if the code returns. Board, wiring and gas valve checks mean opening the casing, so this is engineer-only.",
   "engineer_after_one_reset": true,
   "page_url": "https://combicert.co.uk/boiler-fault-codes/vaillant/#vaillant-f70",
   "source_manual": "ecoTEC plus Installation and Maintenance Instructions (VU, VUW ..6/5-5)",
   "source_doc": "0020244997_07 (15.07.2021)",
   "source_pages": "pp. 60–62, Appendix E Overview of fault codes",
   "source_url": "https://professional.vaillant.co.uk/downloads/product-manuals/ecotec-plus-1/ecotec-plus-combi-and-system-installation-instructions-2422739.pdf",
   "source_type": "manufacturer"
  },
  {
   "id": "glowworm-f27",
   "code": "F.27",
   "brand": "Glow-worm",
   "model_range": "Glow-worm Energy7 combi (25c / 30c / 35c-A)",
   "category": "Ignition / flame",
   "meaning": "Safety shut-down: fault in flame detection (a flame is detected when there should be none).",
   "homeowner_action": "There is no homeowner check that fixes this code. Write down the full code, press reset once, and if it comes back leave the boiler off.",
   "when_to_call_engineer": "Call a Gas Safe registered engineer if the code comes back after one reset. Ignition and flame faults involve gas, so this is engineer-only.",
   "engineer_after_one_reset": true,
   "page_url": "https://combicert.co.uk/boiler-fault-codes/glow-worm/#glowworm-f27",
   "source_manual": "Glow-worm Energy7 Installation and Maintenance Instructions",
   "source_doc": "0020300875_01",
   "source_pages": "PDF pp. 51–53, Appendix E Overview of fault codes",
   "source_url": "https://www.glow-worm.co.uk/glow-worm/product-manuals/energy-3/combi-8/energy7-combi-installation-and-maintenance-instructions-1948938.pdf",
   "source_type": "manufacturer"
  },
  {
   "id": "glowworm-f28",
   "code": "F.28",
   "brand": "Glow-worm",
   "model_range": "Glow-worm Energy7 combi (25c / 30c / 35c-A)",
   "category": "Ignition / flame",
   "meaning": "Ignition unsuccessful when starting.",
   "homeowner_action": "There is no homeowner check that fixes this code. Write down the full code, press reset once, and if it comes back leave the boiler off.",
   "when_to_call_engineer": "Call a Gas Safe registered engineer if the code comes back after one reset. Ignition and flame faults involve gas, so this is engineer-only.",
   "engineer_after_one_reset": true,
   "page_url": "https://combicert.co.uk/boiler-fault-codes/glow-worm/#glowworm-f28",
   "source_manual": "Glow-worm Energy7 Installation and Maintenance Instructions",
   "source_doc": "0020300875_01",
   "source_pages": "PDF pp. 51–53, Appendix E Overview of fault codes",
   "source_url": "https://www.glow-worm.co.uk/glow-worm/product-manuals/energy-3/combi-8/energy7-combi-installation-and-maintenance-instructions-1948938.pdf",
   "source_type": "manufacturer"
  },
  {
   "id": "glowworm-f29",
   "code": "F.29",
   "brand": "Glow-worm",
   "model_range": "Glow-worm Energy7 combi (25c / 30c / 35c-A)",
   "category": "Ignition / flame",
   "meaning": "Flame loss during operation.",
   "homeowner_action": "Check another gas appliance such as the hob works, the gas meter valve is on and, on a prepayment meter, there is credit. In freezing weather, check the plastic condensate pipe outside: if it is frozen, pour warm (not boiling) water along it. Then press reset once. If the code comes back, stop resetting.",
   "when_to_call_engineer": "Call a Gas Safe registered engineer if the gas supply is fine and the code returns after one reset. Ignition and flame faults involve gas, so this is engineer-only.",
   "engineer_after_one_reset": false,
   "page_url": "https://combicert.co.uk/boiler-fault-codes/glow-worm/#glowworm-f29",
   "source_manual": "Glow-worm Energy7 Installation and Maintenance Instructions",
   "source_doc": "0020300875_01",
   "source_pages": "PDF pp. 51–53, Appendix E Overview of fault codes",
   "source_url": "https://www.glow-worm.co.uk/glow-worm/product-manuals/energy-3/combi-8/energy7-combi-installation-and-maintenance-instructions-1948938.pdf",
   "source_type": "manufacturer"
  },
  {
   "id": "glowworm-f61",
   "code": "F.61",
   "brand": "Glow-worm",
   "model_range": "Glow-worm Energy7 combi (25c / 30c / 35c-A)",
   "category": "Ignition / flame",
   "meaning": "Gas valve assembly control fault.",
   "homeowner_action": "There is no homeowner check that fixes this code. Write down the full code, press reset once, and if it comes back leave the boiler off.",
   "when_to_call_engineer": "Call a Gas Safe registered engineer if the code comes back after one reset. Ignition and flame faults involve gas, so this is engineer-only.",
   "engineer_after_one_reset": true,
   "page_url": "https://combicert.co.uk/boiler-fault-codes/glow-worm/#glowworm-f61",
   "source_manual": "Glow-worm Energy7 Installation and Maintenance Instructions",
   "source_doc": "0020300875_01",
   "source_pages": "PDF pp. 51–53, Appendix E Overview of fault codes",
   "source_url": "https://www.glow-worm.co.uk/glow-worm/product-manuals/energy-3/combi-8/energy7-combi-installation-and-maintenance-instructions-1948938.pdf",
   "source_type": "manufacturer"
  },
  {
   "id": "glowworm-f62",
   "code": "F.62",
   "brand": "Glow-worm",
   "model_range": "Glow-worm Energy7 combi (25c / 30c / 35c-A)",
   "category": "Ignition / flame",
   "meaning": "Gas valve switch-off control fault: the valve shuts off late.",
   "homeowner_action": "There is no homeowner check that fixes this code. Write down the full code, press reset once, and if it comes back leave the boiler off.",
   "when_to_call_engineer": "Call a Gas Safe registered engineer if the code comes back after one reset. Ignition and flame faults involve gas, so this is engineer-only.",
   "engineer_after_one_reset": true,
   "page_url": "https://combicert.co.uk/boiler-fault-codes/glow-worm/#glowworm-f62",
   "source_manual": "Glow-worm Energy7 Installation and Maintenance Instructions",
   "source_doc": "0020300875_01",
   "source_pages": "PDF pp. 51–53, Appendix E Overview of fault codes",
   "source_url": "https://www.glow-worm.co.uk/glow-worm/product-manuals/energy-3/combi-8/energy7-combi-installation-and-maintenance-instructions-1948938.pdf",
   "source_type": "manufacturer"
  },
  {
   "id": "glowworm-f67",
   "code": "F.67",
   "brand": "Glow-worm",
   "model_range": "Glow-worm Energy7 combi (25c / 30c / 35c-A)",
   "category": "Ignition / flame",
   "meaning": "Implausible flame signal returned to the electronics.",
   "homeowner_action": "There is no homeowner check that fixes this code. Write down the full code, press reset once, and if it comes back leave the boiler off.",
   "when_to_call_engineer": "Call a Gas Safe registered engineer if the code comes back after one reset. Ignition and flame faults involve gas, so this is engineer-only.",
   "engineer_after_one_reset": true,
   "page_url": "https://combicert.co.uk/boiler-fault-codes/glow-worm/#glowworm-f67",
   "source_manual": "Glow-worm Energy7 Installation and Maintenance Instructions",
   "source_doc": "0020300875_01",
   "source_pages": "PDF pp. 51–53, Appendix E Overview of fault codes",
   "source_url": "https://www.glow-worm.co.uk/glow-worm/product-manuals/energy-3/combi-8/energy7-combi-installation-and-maintenance-instructions-1948938.pdf",
   "source_type": "manufacturer"
  },
  {
   "id": "glowworm-f68",
   "code": "F.68",
   "brand": "Glow-worm",
   "model_range": "Glow-worm Energy7 combi (25c / 30c / 35c-A)",
   "category": "Ignition / flame",
   "meaning": "Unstable flame signal.",
   "homeowner_action": "There is no homeowner check that fixes this code. Write down the full code, press reset once, and if it comes back leave the boiler off.",
   "when_to_call_engineer": "Call a Gas Safe registered engineer if the code comes back after one reset. Ignition and flame faults involve gas, so this is engineer-only.",
   "engineer_after_one_reset": true,
   "page_url": "https://combicert.co.uk/boiler-fault-codes/glow-worm/#glowworm-f68",
   "source_manual": "Glow-worm Energy7 Installation and Maintenance Instructions",
   "source_doc": "0020300875_01",
   "source_pages": "PDF pp. 51–53, Appendix E Overview of fault codes",
   "source_url": "https://www.glow-worm.co.uk/glow-worm/product-manuals/energy-3/combi-8/energy7-combi-installation-and-maintenance-instructions-1948938.pdf",
   "source_type": "manufacturer"
  },
  {
   "id": "glowworm-f87",
   "code": "F.87",
   "brand": "Glow-worm",
   "model_range": "Glow-worm Energy7 combi (25c / 30c / 35c-A)",
   "category": "Ignition / flame",
   "meaning": "Electrode fault: electrodes not connected, connected wrongly or shorted.",
   "homeowner_action": "There is no homeowner check that fixes this code. Write down the full code, press reset once, and if it comes back leave the boiler off.",
   "when_to_call_engineer": "Call a Gas Safe registered engineer if the code comes back after one reset. Ignition and flame faults involve gas, so this is engineer-only.",
   "engineer_after_one_reset": true,
   "page_url": "https://combicert.co.uk/boiler-fault-codes/glow-worm/#glowworm-f87",
   "source_manual": "Glow-worm Energy7 Installation and Maintenance Instructions",
   "source_doc": "0020300875_01",
   "source_pages": "PDF pp. 51–53, Appendix E Overview of fault codes",
   "source_url": "https://www.glow-worm.co.uk/glow-worm/product-manuals/energy-3/combi-8/energy7-combi-installation-and-maintenance-instructions-1948938.pdf",
   "source_type": "manufacturer"
  },
  {
   "id": "glowworm-f88",
   "code": "F.88",
   "brand": "Glow-worm",
   "model_range": "Glow-worm Energy7 combi (25c / 30c / 35c-A)",
   "category": "Ignition / flame",
   "meaning": "Gas valve assembly not connected, connected wrongly or shorted.",
   "homeowner_action": "There is no homeowner check that fixes this code. Write down the full code, press reset once, and if it comes back leave the boiler off.",
   "when_to_call_engineer": "Call a Gas Safe registered engineer if the code comes back after one reset. Ignition and flame faults involve gas, so this is engineer-only.",
   "engineer_after_one_reset": true,
   "page_url": "https://combicert.co.uk/boiler-fault-codes/glow-worm/#glowworm-f88",
   "source_manual": "Glow-worm Energy7 Installation and Maintenance Instructions",
   "source_doc": "0020300875_01",
   "source_pages": "PDF pp. 51–53, Appendix E Overview of fault codes",
   "source_url": "https://www.glow-worm.co.uk/glow-worm/product-manuals/energy-3/combi-8/energy7-combi-installation-and-maintenance-instructions-1948938.pdf",
   "source_type": "manufacturer"
  },
  {
   "id": "glowworm-f22",
   "code": "F.22",
   "brand": "Glow-worm",
   "model_range": "Glow-worm Energy7 combi (25c / 30c / 35c-A)",
   "category": "Water pressure / circulation",
   "meaning": "Safety shut-down: not enough water in the boiler (low pressure).",
   "homeowner_action": "Look at the pressure gauge while the boiler is cold. If it is below about 1 bar, top it up with the filling loop exactly as your user guide shows, to about 1–1.5 bar or the figure in your guide, then close the loop fully. Check the radiator valves are open, then press reset once.",
   "when_to_call_engineer": "Call a Gas Safe registered engineer if you have to top up more than once every few months, the gauge goes above about 2.5 bar when hot, water drips from the outside overflow pipe, or the code returns after topping up.",
   "engineer_after_one_reset": false,
   "page_url": "https://combicert.co.uk/boiler-fault-codes/glow-worm/#glowworm-f22",
   "source_manual": "Glow-worm Energy7 Installation and Maintenance Instructions",
   "source_doc": "0020300875_01",
   "source_pages": "PDF pp. 51–53, Appendix E Overview of fault codes",
   "source_url": "https://www.glow-worm.co.uk/glow-worm/product-manuals/energy-3/combi-8/energy7-combi-installation-and-maintenance-instructions-1948938.pdf",
   "source_type": "manufacturer"
  },
  {
   "id": "glowworm-f23",
   "code": "F.23",
   "brand": "Glow-worm",
   "model_range": "Glow-worm Energy7 combi (25c / 30c / 35c-A)",
   "category": "Water pressure / circulation",
   "meaning": "Safety shut-down: the flow/return temperature difference is too large.",
   "homeowner_action": "There is no homeowner check that fixes this code. Write down the full code, press reset once, and if it comes back leave the boiler off.",
   "when_to_call_engineer": "Call a Gas Safe registered engineer if you have to top up more than once every few months, the gauge goes above about 2.5 bar when hot, water drips from the outside overflow pipe, or the code returns after topping up.",
   "engineer_after_one_reset": true,
   "page_url": "https://combicert.co.uk/boiler-fault-codes/glow-worm/#glowworm-f23",
   "source_manual": "Glow-worm Energy7 Installation and Maintenance Instructions",
   "source_doc": "0020300875_01",
   "source_pages": "PDF pp. 51–53, Appendix E Overview of fault codes",
   "source_url": "https://www.glow-worm.co.uk/glow-worm/product-manuals/energy-3/combi-8/energy7-combi-installation-and-maintenance-instructions-1948938.pdf",
   "source_type": "manufacturer"
  },
  {
   "id": "glowworm-f73",
   "code": "F.73",
   "brand": "Glow-worm",
   "model_range": "Glow-worm Energy7 combi (25c / 30c / 35c-A)",
   "category": "Water pressure / circulation",
   "meaning": "Water pressure sensor not connected or short circuited.",
   "homeowner_action": "There is no homeowner check that fixes this code. Write down the full code, press reset once, and if it comes back leave the boiler off.",
   "when_to_call_engineer": "Call a Gas Safe registered engineer if you have to top up more than once every few months, the gauge goes above about 2.5 bar when hot, water drips from the outside overflow pipe, or the code returns after topping up.",
   "engineer_after_one_reset": true,
   "page_url": "https://combicert.co.uk/boiler-fault-codes/glow-worm/#glowworm-f73",
   "source_manual": "Glow-worm Energy7 Installation and Maintenance Instructions",
   "source_doc": "0020300875_01",
   "source_pages": "PDF pp. 51–53, Appendix E Overview of fault codes",
   "source_url": "https://www.glow-worm.co.uk/glow-worm/product-manuals/energy-3/combi-8/energy7-combi-installation-and-maintenance-instructions-1948938.pdf",
   "source_type": "manufacturer"
  },
  {
   "id": "glowworm-f75",
   "code": "F.75",
   "brand": "Glow-worm",
   "model_range": "Glow-worm Energy7 combi (25c / 30c / 35c-A)",
   "category": "Water pressure / circulation",
   "meaning": "Pressure sensor fault: no pressure rise seen when the pump starts.",
   "homeowner_action": "There is no homeowner check that fixes this code. Write down the full code, press reset once, and if it comes back leave the boiler off.",
   "when_to_call_engineer": "Call a Gas Safe registered engineer if you have to top up more than once every few months, the gauge goes above about 2.5 bar when hot, water drips from the outside overflow pipe, or the code returns after topping up.",
   "engineer_after_one_reset": true,
   "page_url": "https://combicert.co.uk/boiler-fault-codes/glow-worm/#glowworm-f75",
   "source_manual": "Glow-worm Energy7 Installation and Maintenance Instructions",
   "source_doc": "0020300875_01",
   "source_pages": "PDF pp. 51–53, Appendix E Overview of fault codes",
   "source_url": "https://www.glow-worm.co.uk/glow-worm/product-manuals/energy-3/combi-8/energy7-combi-installation-and-maintenance-instructions-1948938.pdf",
   "source_type": "manufacturer"
  },
  {
   "id": "glowworm-f83",
   "code": "F.83",
   "brand": "Glow-worm",
   "model_range": "Glow-worm Energy7 combi (25c / 30c / 35c-A)",
   "category": "Water pressure / circulation",
   "meaning": "Dry fire: little or no temperature change at the flow or return sensor when the burner starts.",
   "homeowner_action": "There is no homeowner check that fixes this code. Write down the full code, press reset once, and if it comes back leave the boiler off.",
   "when_to_call_engineer": "Call a Gas Safe registered engineer if you have to top up more than once every few months, the gauge goes above about 2.5 bar when hot, water drips from the outside overflow pipe, or the code returns after topping up.",
   "engineer_after_one_reset": true,
   "page_url": "https://combicert.co.uk/boiler-fault-codes/glow-worm/#glowworm-f83",
   "source_manual": "Glow-worm Energy7 Installation and Maintenance Instructions",
   "source_doc": "0020300875_01",
   "source_pages": "PDF pp. 51–53, Appendix E Overview of fault codes",
   "source_url": "https://www.glow-worm.co.uk/glow-worm/product-manuals/energy-3/combi-8/energy7-combi-installation-and-maintenance-instructions-1948938.pdf",
   "source_type": "manufacturer"
  },
  {
   "id": "glowworm-f89",
   "code": "F.89",
   "brand": "Glow-worm",
   "model_range": "Glow-worm Energy7 combi (25c / 30c / 35c-A)",
   "category": "Water pressure / circulation",
   "meaning": "Pump not connected or connected wrongly.",
   "homeowner_action": "There is no homeowner check that fixes this code. Write down the full code, press reset once, and if it comes back leave the boiler off.",
   "when_to_call_engineer": "Call a Gas Safe registered engineer if you have to top up more than once every few months, the gauge goes above about 2.5 bar when hot, water drips from the outside overflow pipe, or the code returns after topping up.",
   "engineer_after_one_reset": true,
   "page_url": "https://combicert.co.uk/boiler-fault-codes/glow-worm/#glowworm-f89",
   "source_manual": "Glow-worm Energy7 Installation and Maintenance Instructions",
   "source_doc": "0020300875_01",
   "source_pages": "PDF pp. 51–53, Appendix E Overview of fault codes",
   "source_url": "https://www.glow-worm.co.uk/glow-worm/product-manuals/energy-3/combi-8/energy7-combi-installation-and-maintenance-instructions-1948938.pdf",
   "source_type": "manufacturer"
  },
  {
   "id": "glowworm-f20",
   "code": "F.20",
   "brand": "Glow-worm",
   "model_range": "Glow-worm Energy7 combi (25c / 30c / 35c-A)",
   "category": "Temperature / overheat",
   "meaning": "Safety shut-down: overheating temperature reached.",
   "homeowner_action": "Let the boiler cool for 20 to 30 minutes, then press reset once. If the code comes back, leave the boiler off.",
   "when_to_call_engineer": "Call a Gas Safe registered engineer if the code comes back after one reset. Overheat shut-downs are safety devices doing their job, so this is engineer-only.",
   "engineer_after_one_reset": true,
   "page_url": "https://combicert.co.uk/boiler-fault-codes/glow-worm/#glowworm-f20",
   "source_manual": "Glow-worm Energy7 Installation and Maintenance Instructions",
   "source_doc": "0020300875_01",
   "source_pages": "PDF pp. 51–53, Appendix E Overview of fault codes",
   "source_url": "https://www.glow-worm.co.uk/glow-worm/product-manuals/energy-3/combi-8/energy7-combi-installation-and-maintenance-instructions-1948938.pdf",
   "source_type": "manufacturer"
  },
  {
   "id": "glowworm-f24",
   "code": "F.24",
   "brand": "Glow-worm",
   "model_range": "Glow-worm Energy7 combi (25c / 30c / 35c-A)",
   "category": "Temperature / overheat",
   "meaning": "Safety shut-down: the temperature rose too fast.",
   "homeowner_action": "Let the boiler cool for 20 to 30 minutes, then press reset once. If the code comes back, leave the boiler off.",
   "when_to_call_engineer": "Call a Gas Safe registered engineer if the code comes back after one reset. Overheat shut-downs are safety devices doing their job, so this is engineer-only.",
   "engineer_after_one_reset": true,
   "page_url": "https://combicert.co.uk/boiler-fault-codes/glow-worm/#glowworm-f24",
   "source_manual": "Glow-worm Energy7 Installation and Maintenance Instructions",
   "source_doc": "0020300875_01",
   "source_pages": "PDF pp. 51–53, Appendix E Overview of fault codes",
   "source_url": "https://www.glow-worm.co.uk/glow-worm/product-manuals/energy-3/combi-8/energy7-combi-installation-and-maintenance-instructions-1948938.pdf",
   "source_type": "manufacturer"
  },
  {
   "id": "glowworm-f25",
   "code": "F.25",
   "brand": "Glow-worm",
   "model_range": "Glow-worm Energy7 combi (25c / 30c / 35c-A)",
   "category": "Flue / fan / air",
   "meaning": "Safety shut-down: flue gas temperature too high.",
   "homeowner_action": "There is no homeowner check that fixes this code. Write down the full code, press reset once, and if it comes back leave the boiler off.",
   "when_to_call_engineer": "Call a Gas Safe registered engineer if the terminal looks clear and the code returns. Flue and fan faults can affect how combustion gases leave your home, so this is engineer-only.",
   "engineer_after_one_reset": true,
   "page_url": "https://combicert.co.uk/boiler-fault-codes/glow-worm/#glowworm-f25",
   "source_manual": "Glow-worm Energy7 Installation and Maintenance Instructions",
   "source_doc": "0020300875_01",
   "source_pages": "PDF pp. 51–53, Appendix E Overview of fault codes",
   "source_url": "https://www.glow-worm.co.uk/glow-worm/product-manuals/energy-3/combi-8/energy7-combi-installation-and-maintenance-instructions-1948938.pdf",
   "source_type": "manufacturer"
  },
  {
   "id": "glowworm-f32",
   "code": "F.32",
   "brand": "Glow-worm",
   "model_range": "Glow-worm Energy7 combi (25c / 30c / 35c-A)",
   "category": "Flue / fan / air",
   "meaning": "Fan fault (the manual also notes the fan frost protection function).",
   "homeowner_action": "There is no homeowner check that fixes this code. Write down the full code, press reset once, and if it comes back leave the boiler off.",
   "when_to_call_engineer": "Call a Gas Safe registered engineer if the terminal looks clear and the code returns. Flue and fan faults can affect how combustion gases leave your home, so this is engineer-only.",
   "engineer_after_one_reset": true,
   "page_url": "https://combicert.co.uk/boiler-fault-codes/glow-worm/#glowworm-f32",
   "source_manual": "Glow-worm Energy7 Installation and Maintenance Instructions",
   "source_doc": "0020300875_01",
   "source_pages": "PDF pp. 51–53, Appendix E Overview of fault codes",
   "source_url": "https://www.glow-worm.co.uk/glow-worm/product-manuals/energy-3/combi-8/energy7-combi-installation-and-maintenance-instructions-1948938.pdf",
   "source_type": "manufacturer"
  },
  {
   "id": "glowworm-f00",
   "code": "F.00",
   "brand": "Glow-worm",
   "model_range": "Glow-worm Energy7 combi (25c / 30c / 35c-A)",
   "category": "Sensors / thermistors",
   "meaning": "Flow temperature sensor fault (open circuit).",
   "homeowner_action": "Write down the full code. Check the boiler has power, then switch it off and on at its mains switch or press reset once. If the code comes back, leave it there: sensors are inside the casing.",
   "when_to_call_engineer": "Call a Gas Safe registered engineer if the code returns. Testing and replacing sensors means opening the casing, so this is engineer-only.",
   "engineer_after_one_reset": true,
   "page_url": "https://combicert.co.uk/boiler-fault-codes/glow-worm/#glowworm-f00",
   "source_manual": "Glow-worm Energy7 Installation and Maintenance Instructions",
   "source_doc": "0020300875_01",
   "source_pages": "PDF pp. 51–53, Appendix E Overview of fault codes",
   "source_url": "https://www.glow-worm.co.uk/glow-worm/product-manuals/energy-3/combi-8/energy7-combi-installation-and-maintenance-instructions-1948938.pdf",
   "source_type": "manufacturer"
  },
  {
   "id": "glowworm-f01",
   "code": "F.01",
   "brand": "Glow-worm",
   "model_range": "Glow-worm Energy7 combi (25c / 30c / 35c-A)",
   "category": "Sensors / thermistors",
   "meaning": "Return temperature sensor fault (open circuit).",
   "homeowner_action": "Write down the full code. Check the boiler has power, then switch it off and on at its mains switch or press reset once. If the code comes back, leave it there: sensors are inside the casing.",
   "when_to_call_engineer": "Call a Gas Safe registered engineer if the code returns. Testing and replacing sensors means opening the casing, so this is engineer-only.",
   "engineer_after_one_reset": true,
   "page_url": "https://combicert.co.uk/boiler-fault-codes/glow-worm/#glowworm-f01",
   "source_manual": "Glow-worm Energy7 Installation and Maintenance Instructions",
   "source_doc": "0020300875_01",
   "source_pages": "PDF pp. 51–53, Appendix E Overview of fault codes",
   "source_url": "https://www.glow-worm.co.uk/glow-worm/product-manuals/energy-3/combi-8/energy7-combi-installation-and-maintenance-instructions-1948938.pdf",
   "source_type": "manufacturer"
  },
  {
   "id": "glowworm-f10",
   "code": "F.10",
   "brand": "Glow-worm",
   "model_range": "Glow-worm Energy7 combi (25c / 30c / 35c-A)",
   "category": "Sensors / thermistors",
   "meaning": "Flow temperature sensor short circuit.",
   "homeowner_action": "Write down the full code. Check the boiler has power, then switch it off and on at its mains switch or press reset once. If the code comes back, leave it there: sensors are inside the casing.",
   "when_to_call_engineer": "Call a Gas Safe registered engineer if the code returns. Testing and replacing sensors means opening the casing, so this is engineer-only.",
   "engineer_after_one_reset": true,
   "page_url": "https://combicert.co.uk/boiler-fault-codes/glow-worm/#glowworm-f10",
   "source_manual": "Glow-worm Energy7 Installation and Maintenance Instructions",
   "source_doc": "0020300875_01",
   "source_pages": "PDF pp. 51–53, Appendix E Overview of fault codes",
   "source_url": "https://www.glow-worm.co.uk/glow-worm/product-manuals/energy-3/combi-8/energy7-combi-installation-and-maintenance-instructions-1948938.pdf",
   "source_type": "manufacturer"
  },
  {
   "id": "glowworm-f11",
   "code": "F.11",
   "brand": "Glow-worm",
   "model_range": "Glow-worm Energy7 combi (25c / 30c / 35c-A)",
   "category": "Sensors / thermistors",
   "meaning": "Return temperature sensor short circuit.",
   "homeowner_action": "Write down the full code. Check the boiler has power, then switch it off and on at its mains switch or press reset once. If the code comes back, leave it there: sensors are inside the casing.",
   "when_to_call_engineer": "Call a Gas Safe registered engineer if the code returns. Testing and replacing sensors means opening the casing, so this is engineer-only.",
   "engineer_after_one_reset": true,
   "page_url": "https://combicert.co.uk/boiler-fault-codes/glow-worm/#glowworm-f11",
   "source_manual": "Glow-worm Energy7 Installation and Maintenance Instructions",
   "source_doc": "0020300875_01",
   "source_pages": "PDF pp. 51–53, Appendix E Overview of fault codes",
   "source_url": "https://www.glow-worm.co.uk/glow-worm/product-manuals/energy-3/combi-8/energy7-combi-installation-and-maintenance-instructions-1948938.pdf",
   "source_type": "manufacturer"
  },
  {
   "id": "glowworm-f71",
   "code": "F.71",
   "brand": "Glow-worm",
   "model_range": "Glow-worm Energy7 combi (25c / 30c / 35c-A)",
   "category": "Sensors / thermistors",
   "meaning": "Flow or return temperature sensor stuck at a constant value.",
   "homeowner_action": "Write down the full code. Check the boiler has power, then switch it off and on at its mains switch or press reset once. If the code comes back, leave it there: sensors are inside the casing.",
   "when_to_call_engineer": "Call a Gas Safe registered engineer if the code returns. Testing and replacing sensors means opening the casing, so this is engineer-only.",
   "engineer_after_one_reset": true,
   "page_url": "https://combicert.co.uk/boiler-fault-codes/glow-worm/#glowworm-f71",
   "source_manual": "Glow-worm Energy7 Installation and Maintenance Instructions",
   "source_doc": "0020300875_01",
   "source_pages": "PDF pp. 51–53, Appendix E Overview of fault codes",
   "source_url": "https://www.glow-worm.co.uk/glow-worm/product-manuals/energy-3/combi-8/energy7-combi-installation-and-maintenance-instructions-1948938.pdf",
   "source_type": "manufacturer"
  },
  {
   "id": "glowworm-f49",
   "code": "F.49",
   "brand": "Glow-worm",
   "model_range": "Glow-worm Energy7 combi (25c / 30c / 35c-A)",
   "category": "PCB / electrical",
   "meaning": "eBUS fault: voltage too low.",
   "homeowner_action": "Write down the full code. Check the boiler has power and nothing else in the house has tripped, then switch the boiler off and on at its mains switch or press reset once. If the code comes back, leave the boiler off.",
   "when_to_call_engineer": "Call a Gas Safe registered engineer if the code returns. Board, wiring and gas valve checks mean opening the casing, so this is engineer-only.",
   "engineer_after_one_reset": true,
   "page_url": "https://combicert.co.uk/boiler-fault-codes/glow-worm/#glowworm-f49",
   "source_manual": "Glow-worm Energy7 Installation and Maintenance Instructions",
   "source_doc": "0020300875_01",
   "source_pages": "PDF pp. 51–53, Appendix E Overview of fault codes",
   "source_url": "https://www.glow-worm.co.uk/glow-worm/product-manuals/energy-3/combi-8/energy7-combi-installation-and-maintenance-instructions-1948938.pdf",
   "source_type": "manufacturer"
  },
  {
   "id": "glowworm-f63",
   "code": "F.63",
   "brand": "Glow-worm",
   "model_range": "Glow-worm Energy7 combi (25c / 30c / 35c-A)",
   "category": "PCB / electrical",
   "meaning": "EEPROM fault.",
   "homeowner_action": "Write down the full code. Check the boiler has power and nothing else in the house has tripped, then switch the boiler off and on at its mains switch or press reset once. If the code comes back, leave the boiler off.",
   "when_to_call_engineer": "Call a Gas Safe registered engineer if the code returns. Board, wiring and gas valve checks mean opening the casing, so this is engineer-only.",
   "engineer_after_one_reset": true,
   "page_url": "https://combicert.co.uk/boiler-fault-codes/glow-worm/#glowworm-f63",
   "source_manual": "Glow-worm Energy7 Installation and Maintenance Instructions",
   "source_doc": "0020300875_01",
   "source_pages": "PDF pp. 51–53, Appendix E Overview of fault codes",
   "source_url": "https://www.glow-worm.co.uk/glow-worm/product-manuals/energy-3/combi-8/energy7-combi-installation-and-maintenance-instructions-1948938.pdf",
   "source_type": "manufacturer"
  },
  {
   "id": "glowworm-f64",
   "code": "F.64",
   "brand": "Glow-worm",
   "model_range": "Glow-worm Energy7 combi (25c / 30c / 35c-A)",
   "category": "PCB / electrical",
   "meaning": "Electronics, sensor or analogue-to-digital converter fault.",
   "homeowner_action": "Write down the full code. Check the boiler has power and nothing else in the house has tripped, then switch the boiler off and on at its mains switch or press reset once. If the code comes back, leave the boiler off.",
   "when_to_call_engineer": "Call a Gas Safe registered engineer if the code returns. Board, wiring and gas valve checks mean opening the casing, so this is engineer-only.",
   "engineer_after_one_reset": true,
   "page_url": "https://combicert.co.uk/boiler-fault-codes/glow-worm/#glowworm-f64",
   "source_manual": "Glow-worm Energy7 Installation and Maintenance Instructions",
   "source_doc": "0020300875_01",
   "source_pages": "PDF pp. 51–53, Appendix E Overview of fault codes",
   "source_url": "https://www.glow-worm.co.uk/glow-worm/product-manuals/energy-3/combi-8/energy7-combi-installation-and-maintenance-instructions-1948938.pdf",
   "source_type": "manufacturer"
  },
  {
   "id": "glowworm-f65",
   "code": "F.65",
   "brand": "Glow-worm",
   "model_range": "Glow-worm Energy7 combi (25c / 30c / 35c-A)",
   "category": "PCB / electrical",
   "meaning": "Electronics temperature too high.",
   "homeowner_action": "Write down the full code. Check the boiler has power and nothing else in the house has tripped, then switch the boiler off and on at its mains switch or press reset once. If the code comes back, leave the boiler off.",
   "when_to_call_engineer": "Call a Gas Safe registered engineer if the code returns. Board, wiring and gas valve checks mean opening the casing, so this is engineer-only.",
   "engineer_after_one_reset": true,
   "page_url": "https://combicert.co.uk/boiler-fault-codes/glow-worm/#glowworm-f65",
   "source_manual": "Glow-worm Energy7 Installation and Maintenance Instructions",
   "source_doc": "0020300875_01",
   "source_pages": "PDF pp. 51–53, Appendix E Overview of fault codes",
   "source_url": "https://www.glow-worm.co.uk/glow-worm/product-manuals/energy-3/combi-8/energy7-combi-installation-and-maintenance-instructions-1948938.pdf",
   "source_type": "manufacturer"
  },
  {
   "id": "glowworm-f70",
   "code": "F.70",
   "brand": "Glow-worm",
   "model_range": "Glow-worm Energy7 combi (25c / 30c / 35c-A)",
   "category": "PCB / electrical",
   "meaning": "Invalid product code (DSN).",
   "homeowner_action": "Write down the full code. Check the boiler has power and nothing else in the house has tripped, then switch the boiler off and on at its mains switch or press reset once. If the code comes back, leave the boiler off.",
   "when_to_call_engineer": "Call a Gas Safe registered engineer if the code returns. Board, wiring and gas valve checks mean opening the casing, so this is engineer-only.",
   "engineer_after_one_reset": true,
   "page_url": "https://combicert.co.uk/boiler-fault-codes/glow-worm/#glowworm-f70",
   "source_manual": "Glow-worm Energy7 Installation and Maintenance Instructions",
   "source_doc": "0020300875_01",
   "source_pages": "PDF pp. 51–53, Appendix E Overview of fault codes",
   "source_url": "https://www.glow-worm.co.uk/glow-worm/product-manuals/energy-3/combi-8/energy7-combi-installation-and-maintenance-instructions-1948938.pdf",
   "source_type": "manufacturer"
  },
  {
   "id": "glowworm-f97",
   "code": "F.97",
   "brand": "Glow-worm",
   "model_range": "Glow-worm Energy7 combi (25c / 30c / 35c-A)",
   "category": "PCB / electrical",
   "meaning": "Main PCB self-test failed.",
   "homeowner_action": "Write down the full code. Check the boiler has power and nothing else in the house has tripped, then switch the boiler off and on at its mains switch or press reset once. If the code comes back, leave the boiler off.",
   "when_to_call_engineer": "Call a Gas Safe registered engineer if the code returns. Board, wiring and gas valve checks mean opening the casing, so this is engineer-only.",
   "engineer_after_one_reset": true,
   "page_url": "https://combicert.co.uk/boiler-fault-codes/glow-worm/#glowworm-f97",
   "source_manual": "Glow-worm Energy7 Installation and Maintenance Instructions",
   "source_doc": "0020300875_01",
   "source_pages": "PDF pp. 51–53, Appendix E Overview of fault codes",
   "source_url": "https://www.glow-worm.co.uk/glow-worm/product-manuals/energy-3/combi-8/energy7-combi-installation-and-maintenance-instructions-1948938.pdf",
   "source_type": "manufacturer"
  },
  {
   "id": "potterton-e09",
   "code": "E09",
   "brand": "Potterton",
   "model_range": "Potterton Assure Combi (25 / 30 / 36)",
   "category": "Ignition / flame",
   "meaning": "Gas valve connection cable fault.",
   "homeowner_action": "There is no homeowner check that fixes this code. Write down the full code, press reset once, and if it comes back leave the boiler off.",
   "when_to_call_engineer": "Call a Gas Safe registered engineer if the code comes back after one reset. Ignition and flame faults involve gas, so this is engineer-only.",
   "engineer_after_one_reset": true,
   "page_url": "https://combicert.co.uk/boiler-fault-codes/potterton/#potterton-e09",
   "source_manual": "Potterton Assure Combi Installation and Service Manual",
   "source_doc": "7717311-01",
   "source_pages": "p. 64, section 10.1 Error codes (Fig. 68)",
   "source_url": "https://www.heatingspareparts.com/content/docs/potterton_47-393-59_compressed_7678846_potterton_assure_combi_installation_and_service_manual.pdf",
   "source_type": "trade-site mirror (no manufacturer-hosted copy found)"
  },
  {
   "id": "potterton-e15",
   "code": "E15",
   "brand": "Potterton",
   "model_range": "Potterton Assure Combi (25 / 30 / 36)",
   "category": "Ignition / flame",
   "meaning": "Gas valve fault.",
   "homeowner_action": "There is no homeowner check that fixes this code. Write down the full code, press reset once, and if it comes back leave the boiler off.",
   "when_to_call_engineer": "Call a Gas Safe registered engineer if the code comes back after one reset. Ignition and flame faults involve gas, so this is engineer-only.",
   "engineer_after_one_reset": true,
   "page_url": "https://combicert.co.uk/boiler-fault-codes/potterton/#potterton-e15",
   "source_manual": "Potterton Assure Combi Installation and Service Manual",
   "source_doc": "7717311-01",
   "source_pages": "p. 64, section 10.1 Error codes (Fig. 68)",
   "source_url": "https://www.heatingspareparts.com/content/docs/potterton_47-393-59_compressed_7678846_potterton_assure_combi_installation_and_service_manual.pdf",
   "source_type": "trade-site mirror (no manufacturer-hosted copy found)"
  },
  {
   "id": "potterton-e128",
   "code": "E128",
   "brand": "Potterton",
   "model_range": "Potterton Assure Combi (25 / 30 / 36)",
   "category": "Ignition / flame",
   "meaning": "Flame failure during normal operation.",
   "homeowner_action": "Check another gas appliance such as the hob works, the gas meter valve is on and, on a prepayment meter, there is credit. In freezing weather, check the plastic condensate pipe outside: if it is frozen, pour warm (not boiling) water along it. Then press reset once. If the code comes back, stop resetting.",
   "when_to_call_engineer": "Call a Gas Safe registered engineer if the gas supply is fine and the code returns after one reset. Ignition and flame faults involve gas, so this is engineer-only.",
   "engineer_after_one_reset": false,
   "page_url": "https://combicert.co.uk/boiler-fault-codes/potterton/#potterton-e128",
   "source_manual": "Potterton Assure Combi Installation and Service Manual",
   "source_doc": "7717311-01",
   "source_pages": "p. 64, section 10.1 Error codes (Fig. 68)",
   "source_url": "https://www.heatingspareparts.com/content/docs/potterton_47-393-59_compressed_7678846_potterton_assure_combi_installation_and_service_manual.pdf",
   "source_type": "trade-site mirror (no manufacturer-hosted copy found)"
  },
  {
   "id": "potterton-e133",
   "code": "E133",
   "brand": "Potterton",
   "model_range": "Potterton Assure Combi (25 / 30 / 36)",
   "category": "Ignition / flame",
   "meaning": "Interruption of the gas supply or flame failure: the boiler could not light or prove a flame.",
   "homeowner_action": "Check another gas appliance such as the hob works, the gas meter valve is on and, on a prepayment meter, there is credit. In freezing weather, check the plastic condensate pipe outside: if it is frozen, pour warm (not boiling) water along it. Then press reset once. If the code comes back, stop resetting.",
   "when_to_call_engineer": "Call a Gas Safe registered engineer if the gas supply is fine and the code returns after one reset. Ignition and flame faults involve gas, so this is engineer-only.",
   "engineer_after_one_reset": false,
   "page_url": "https://combicert.co.uk/boiler-fault-codes/potterton/#potterton-e133",
   "source_manual": "Potterton Assure Combi Installation and Service Manual",
   "source_doc": "7717311-01",
   "source_pages": "p. 64, section 10.1 Error codes (Fig. 68)",
   "source_url": "https://www.heatingspareparts.com/content/docs/potterton_47-393-59_compressed_7678846_potterton_assure_combi_installation_and_service_manual.pdf",
   "source_type": "trade-site mirror (no manufacturer-hosted copy found)"
  },
  {
   "id": "potterton-e135",
   "code": "E135",
   "brand": "Potterton",
   "model_range": "Potterton Assure Combi (25 / 30 / 36)",
   "category": "Ignition / flame",
   "meaning": "Interruption of the gas supply, listed in the manual as an internal error.",
   "homeowner_action": "Check another gas appliance such as the hob works, the gas meter valve is on and, on a prepayment meter, there is credit. In freezing weather, check the plastic condensate pipe outside: if it is frozen, pour warm (not boiling) water along it. Then press reset once. If the code comes back, stop resetting.",
   "when_to_call_engineer": "Call a Gas Safe registered engineer if the gas supply is fine and the code returns after one reset. Ignition and flame faults involve gas, so this is engineer-only.",
   "engineer_after_one_reset": false,
   "page_url": "https://combicert.co.uk/boiler-fault-codes/potterton/#potterton-e135",
   "source_manual": "Potterton Assure Combi Installation and Service Manual",
   "source_doc": "7717311-01",
   "source_pages": "p. 64, section 10.1 Error codes (Fig. 68)",
   "source_url": "https://www.heatingspareparts.com/content/docs/potterton_47-393-59_compressed_7678846_potterton_assure_combi_installation_and_service_manual.pdf",
   "source_type": "trade-site mirror (no manufacturer-hosted copy found)"
  },
  {
   "id": "potterton-e384",
   "code": "E384",
   "brand": "Potterton",
   "model_range": "Potterton Assure Combi (25 / 30 / 36)",
   "category": "Ignition / flame",
   "meaning": "False flame: a flame signal is detected when there should be none.",
   "homeowner_action": "There is no homeowner check that fixes this code. Write down the full code, press reset once, and if it comes back leave the boiler off.",
   "when_to_call_engineer": "Call a Gas Safe registered engineer if the code comes back after one reset. Ignition and flame faults involve gas, so this is engineer-only.",
   "engineer_after_one_reset": true,
   "page_url": "https://combicert.co.uk/boiler-fault-codes/potterton/#potterton-e384",
   "source_manual": "Potterton Assure Combi Installation and Service Manual",
   "source_doc": "7717311-01",
   "source_pages": "p. 64, section 10.1 Error codes (Fig. 68)",
   "source_url": "https://www.heatingspareparts.com/content/docs/potterton_47-393-59_compressed_7678846_potterton_assure_combi_installation_and_service_manual.pdf",
   "source_type": "trade-site mirror (no manufacturer-hosted copy found)"
  },
  {
   "id": "potterton-e109",
   "code": "E109",
   "brand": "Potterton",
   "model_range": "Potterton Assure Combi (25 / 30 / 36)",
   "category": "Water pressure / circulation",
   "meaning": "Pre-circulation fault: the boiler did not see water circulating before lighting.",
   "homeowner_action": "There is no homeowner check that fixes this code. Write down the full code, press reset once, and if it comes back leave the boiler off.",
   "when_to_call_engineer": "Call a Gas Safe registered engineer if you have to top up more than once every few months, the gauge goes above about 2.5 bar when hot, water drips from the outside overflow pipe, or the code returns after topping up.",
   "engineer_after_one_reset": true,
   "page_url": "https://combicert.co.uk/boiler-fault-codes/potterton/#potterton-e109",
   "source_manual": "Potterton Assure Combi Installation and Service Manual",
   "source_doc": "7717311-01",
   "source_pages": "p. 64, section 10.1 Error codes (Fig. 68)",
   "source_url": "https://www.heatingspareparts.com/content/docs/potterton_47-393-59_compressed_7678846_potterton_assure_combi_installation_and_service_manual.pdf",
   "source_type": "trade-site mirror (no manufacturer-hosted copy found)"
  },
  {
   "id": "potterton-e118",
   "code": "E118",
   "brand": "Potterton",
   "model_range": "Potterton Assure Combi (25 / 30 / 36)",
   "category": "Water pressure / circulation",
   "meaning": "Primary system water pressure is too low (the manual says below 0.5 bar).",
   "homeowner_action": "Look at the pressure gauge while the boiler is cold. If it is below about 1 bar, top it up with the filling loop exactly as your user guide shows, to about 1–1.5 bar or the figure in your guide, then close the loop fully. Check the radiator valves are open, then press reset once.",
   "when_to_call_engineer": "Call a Gas Safe registered engineer if you have to top up more than once every few months, the gauge goes above about 2.5 bar when hot, water drips from the outside overflow pipe, or the code returns after topping up.",
   "engineer_after_one_reset": false,
   "page_url": "https://combicert.co.uk/boiler-fault-codes/potterton/#potterton-e118",
   "source_manual": "Potterton Assure Combi Installation and Service Manual",
   "source_doc": "7717311-01",
   "source_pages": "p. 64, section 10.1 Error codes (Fig. 68)",
   "source_url": "https://www.heatingspareparts.com/content/docs/potterton_47-393-59_compressed_7678846_potterton_assure_combi_installation_and_service_manual.pdf",
   "source_type": "trade-site mirror (no manufacturer-hosted copy found)"
  },
  {
   "id": "potterton-e125",
   "code": "E125",
   "brand": "Potterton",
   "model_range": "Potterton Assure Combi (25 / 30 / 36)",
   "category": "Water pressure / circulation",
   "meaning": "Circulation fault in the primary circuit. The manual says it shows if the water temperature hardly changes 15 to 30 seconds after lighting, or overshoots the set temperature by 30 °C twice within 10 minutes.",
   "homeowner_action": "There is no homeowner check that fixes this code. Write down the full code, press reset once, and if it comes back leave the boiler off.",
   "when_to_call_engineer": "Call a Gas Safe registered engineer if you have to top up more than once every few months, the gauge goes above about 2.5 bar when hot, water drips from the outside overflow pipe, or the code returns after topping up.",
   "engineer_after_one_reset": true,
   "page_url": "https://combicert.co.uk/boiler-fault-codes/potterton/#potterton-e125",
   "source_manual": "Potterton Assure Combi Installation and Service Manual",
   "source_doc": "7717311-01",
   "source_pages": "p. 64, section 10.1 Error codes (Fig. 68)",
   "source_url": "https://www.heatingspareparts.com/content/docs/potterton_47-393-59_compressed_7678846_potterton_assure_combi_installation_and_service_manual.pdf",
   "source_type": "trade-site mirror (no manufacturer-hosted copy found)"
  },
  {
   "id": "potterton-e270",
   "code": "E270",
   "brand": "Potterton",
   "model_range": "Potterton Assure Combi (25 / 30 / 36)",
   "category": "Water pressure / circulation",
   "meaning": "Circulation fault (dry fire): the boiler detected it was firing without enough water flow.",
   "homeowner_action": "There is no homeowner check that fixes this code. Write down the full code, press reset once, and if it comes back leave the boiler off.",
   "when_to_call_engineer": "Call a Gas Safe registered engineer if you have to top up more than once every few months, the gauge goes above about 2.5 bar when hot, water drips from the outside overflow pipe, or the code returns after topping up.",
   "engineer_after_one_reset": true,
   "page_url": "https://combicert.co.uk/boiler-fault-codes/potterton/#potterton-e270",
   "source_manual": "Potterton Assure Combi Installation and Service Manual",
   "source_doc": "7717311-01",
   "source_pages": "p. 64, section 10.1 Error codes (Fig. 68)",
   "source_url": "https://www.heatingspareparts.com/content/docs/potterton_47-393-59_compressed_7678846_potterton_assure_combi_installation_and_service_manual.pdf",
   "source_type": "trade-site mirror (no manufacturer-hosted copy found)"
  },
  {
   "id": "potterton-e110",
   "code": "E110",
   "brand": "Potterton",
   "model_range": "Potterton Assure Combi (25 / 30 / 36)",
   "category": "Temperature / overheat",
   "meaning": "The safety (overheat) thermostat has operated: the primary water overheated.",
   "homeowner_action": "Let the boiler cool for 20 to 30 minutes, then press reset once. If the code comes back, leave the boiler off.",
   "when_to_call_engineer": "Call a Gas Safe registered engineer if the code comes back after one reset. Overheat shut-downs are safety devices doing their job, so this is engineer-only.",
   "engineer_after_one_reset": true,
   "page_url": "https://combicert.co.uk/boiler-fault-codes/potterton/#potterton-e110",
   "source_manual": "Potterton Assure Combi Installation and Service Manual",
   "source_doc": "7717311-01",
   "source_pages": "p. 64, section 10.1 Error codes (Fig. 68)",
   "source_url": "https://www.heatingspareparts.com/content/docs/potterton_47-393-59_compressed_7678846_potterton_assure_combi_installation_and_service_manual.pdf",
   "source_type": "trade-site mirror (no manufacturer-hosted copy found)"
  },
  {
   "id": "potterton-e130",
   "code": "E130",
   "brand": "Potterton",
   "model_range": "Potterton Assure Combi (25 / 30 / 36)",
   "category": "Flue / fan / air",
   "meaning": "The flue NTC has operated (flue overheat).",
   "homeowner_action": "There is no homeowner check that fixes this code. Write down the full code, press reset once, and if it comes back leave the boiler off.",
   "when_to_call_engineer": "Call a Gas Safe registered engineer if the terminal looks clear and the code returns. Flue and fan faults can affect how combustion gases leave your home, so this is engineer-only.",
   "engineer_after_one_reset": true,
   "page_url": "https://combicert.co.uk/boiler-fault-codes/potterton/#potterton-e130",
   "source_manual": "Potterton Assure Combi Installation and Service Manual",
   "source_doc": "7717311-01",
   "source_pages": "p. 64, section 10.1 Error codes (Fig. 68)",
   "source_url": "https://www.heatingspareparts.com/content/docs/potterton_47-393-59_compressed_7678846_potterton_assure_combi_installation_and_service_manual.pdf",
   "source_type": "trade-site mirror (no manufacturer-hosted copy found)"
  },
  {
   "id": "potterton-e160",
   "code": "E160",
   "brand": "Potterton",
   "model_range": "Potterton Assure Combi (25 / 30 / 36)",
   "category": "Flue / fan / air",
   "meaning": "Fan or fan wiring fault.",
   "homeowner_action": "There is no homeowner check that fixes this code. Write down the full code, press reset once, and if it comes back leave the boiler off.",
   "when_to_call_engineer": "Call a Gas Safe registered engineer if the terminal looks clear and the code returns. Flue and fan faults can affect how combustion gases leave your home, so this is engineer-only.",
   "engineer_after_one_reset": true,
   "page_url": "https://combicert.co.uk/boiler-fault-codes/potterton/#potterton-e160",
   "source_manual": "Potterton Assure Combi Installation and Service Manual",
   "source_doc": "7717311-01",
   "source_pages": "p. 64, section 10.1 Error codes (Fig. 68)",
   "source_url": "https://www.heatingspareparts.com/content/docs/potterton_47-393-59_compressed_7678846_potterton_assure_combi_installation_and_service_manual.pdf",
   "source_type": "trade-site mirror (no manufacturer-hosted copy found)"
  },
  {
   "id": "potterton-e20",
   "code": "E20",
   "brand": "Potterton",
   "model_range": "Potterton Assure Combi (25 / 30 / 36)",
   "category": "Sensors / thermistors",
   "meaning": "Central heating (flow) NTC sensor fault.",
   "homeowner_action": "Write down the full code. Check the boiler has power, then switch it off and on at its mains switch or press reset once. If the code comes back, leave it there: sensors are inside the casing.",
   "when_to_call_engineer": "Call a Gas Safe registered engineer if the code returns. Testing and replacing sensors means opening the casing, so this is engineer-only.",
   "engineer_after_one_reset": true,
   "page_url": "https://combicert.co.uk/boiler-fault-codes/potterton/#potterton-e20",
   "source_manual": "Potterton Assure Combi Installation and Service Manual",
   "source_doc": "7717311-01",
   "source_pages": "p. 64, section 10.1 Error codes (Fig. 68)",
   "source_url": "https://www.heatingspareparts.com/content/docs/potterton_47-393-59_compressed_7678846_potterton_assure_combi_installation_and_service_manual.pdf",
   "source_type": "trade-site mirror (no manufacturer-hosted copy found)"
  },
  {
   "id": "potterton-e28",
   "code": "E28",
   "brand": "Potterton",
   "model_range": "Potterton Assure Combi (25 / 30 / 36)",
   "category": "Sensors / thermistors",
   "meaning": "Flue NTC sensor fault.",
   "homeowner_action": "Write down the full code. Check the boiler has power, then switch it off and on at its mains switch or press reset once. If the code comes back, leave it there: sensors are inside the casing.",
   "when_to_call_engineer": "Call a Gas Safe registered engineer if the code returns. Testing and replacing sensors means opening the casing, so this is engineer-only.",
   "engineer_after_one_reset": true,
   "page_url": "https://combicert.co.uk/boiler-fault-codes/potterton/#potterton-e28",
   "source_manual": "Potterton Assure Combi Installation and Service Manual",
   "source_doc": "7717311-01",
   "source_pages": "p. 64, section 10.1 Error codes (Fig. 68)",
   "source_url": "https://www.heatingspareparts.com/content/docs/potterton_47-393-59_compressed_7678846_potterton_assure_combi_installation_and_service_manual.pdf",
   "source_type": "trade-site mirror (no manufacturer-hosted copy found)"
  },
  {
   "id": "potterton-e40",
   "code": "E40",
   "brand": "Potterton",
   "model_range": "Potterton Assure Combi (25 / 30 / 36)",
   "category": "Sensors / thermistors",
   "meaning": "Central heating return NTC sensor fault.",
   "homeowner_action": "Write down the full code. Check the boiler has power, then switch it off and on at its mains switch or press reset once. If the code comes back, leave it there: sensors are inside the casing.",
   "when_to_call_engineer": "Call a Gas Safe registered engineer if the code returns. Testing and replacing sensors means opening the casing, so this is engineer-only.",
   "engineer_after_one_reset": true,
   "page_url": "https://combicert.co.uk/boiler-fault-codes/potterton/#potterton-e40",
   "source_manual": "Potterton Assure Combi Installation and Service Manual",
   "source_doc": "7717311-01",
   "source_pages": "p. 64, section 10.1 Error codes (Fig. 68)",
   "source_url": "https://www.heatingspareparts.com/content/docs/potterton_47-393-59_compressed_7678846_potterton_assure_combi_installation_and_service_manual.pdf",
   "source_type": "trade-site mirror (no manufacturer-hosted copy found)"
  },
  {
   "id": "potterton-e154",
   "code": "E154",
   "brand": "Potterton",
   "model_range": "Potterton Assure Combi (25 / 30 / 36)",
   "category": "Sensors / thermistors",
   "meaning": "Flow/return sensor temperature test fault.",
   "homeowner_action": "Write down the full code. Check the boiler has power, then switch it off and on at its mains switch or press reset once. If the code comes back, leave it there: sensors are inside the casing.",
   "when_to_call_engineer": "Call a Gas Safe registered engineer if the code returns. Testing and replacing sensors means opening the casing, so this is engineer-only.",
   "engineer_after_one_reset": true,
   "page_url": "https://combicert.co.uk/boiler-fault-codes/potterton/#potterton-e154",
   "source_manual": "Potterton Assure Combi Installation and Service Manual",
   "source_doc": "7717311-01",
   "source_pages": "p. 64, section 10.1 Error codes (Fig. 68)",
   "source_url": "https://www.heatingspareparts.com/content/docs/potterton_47-393-59_compressed_7678846_potterton_assure_combi_installation_and_service_manual.pdf",
   "source_type": "trade-site mirror (no manufacturer-hosted copy found)"
  },
  {
   "id": "potterton-e321",
   "code": "E321",
   "brand": "Potterton",
   "model_range": "Potterton Assure Combi (25 / 30 / 36)",
   "category": "Sensors / thermistors",
   "meaning": "Hot water NTC sensor fault.",
   "homeowner_action": "Write down the full code. Check the boiler has power, then switch it off and on at its mains switch or press reset once. If the code comes back, leave it there: sensors are inside the casing.",
   "when_to_call_engineer": "Call a Gas Safe registered engineer if the code returns. Testing and replacing sensors means opening the casing, so this is engineer-only.",
   "engineer_after_one_reset": true,
   "page_url": "https://combicert.co.uk/boiler-fault-codes/potterton/#potterton-e321",
   "source_manual": "Potterton Assure Combi Installation and Service Manual",
   "source_doc": "7717311-01",
   "source_pages": "p. 64, section 10.1 Error codes (Fig. 68)",
   "source_url": "https://www.heatingspareparts.com/content/docs/potterton_47-393-59_compressed_7678846_potterton_assure_combi_installation_and_service_manual.pdf",
   "source_type": "trade-site mirror (no manufacturer-hosted copy found)"
  },
  {
   "id": "potterton-e83",
   "code": "E83",
   "brand": "Potterton",
   "model_range": "Potterton Assure Combi (25 / 30 / 36)",
   "category": "Other / controls",
   "meaning": "Communication error.",
   "homeowner_action": "There is no homeowner check that fixes this code. Write down the full code, press reset once, and if it comes back leave the boiler off.",
   "when_to_call_engineer": "Call a Gas Safe registered engineer if the code stays after you have checked the controls, or keeps coming back.",
   "engineer_after_one_reset": true,
   "page_url": "https://combicert.co.uk/boiler-fault-codes/potterton/#potterton-e83",
   "source_manual": "Potterton Assure Combi Installation and Service Manual",
   "source_doc": "7717311-01",
   "source_pages": "p. 64, section 10.1 Error codes (Fig. 68)",
   "source_url": "https://www.heatingspareparts.com/content/docs/potterton_47-393-59_compressed_7678846_potterton_assure_combi_installation_and_service_manual.pdf",
   "source_type": "trade-site mirror (no manufacturer-hosted copy found)"
  }
 ]
}