19 fault codes with plain-English explanations, severity ratings, DIY guidance, and repair cost estimates.
Replaced by: Baxi 800 Combi
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The GC number on your boiler's data badge identifies the exact appliance and production years, as recorded in the UK Product Characteristics Database.
| GC number | Appliance (register name) | Produced |
|---|---|---|
| 47-075-96 | Duo-tec 24 Combi ErP | 2015–present |
| 47-075-97 | Duo-tec 28 Combi ErP | 2015–present |
| 47-075-98 | DUO-TEC 28 LPG COMBI ErP | 2015–present |
| 47-075-99 | Duo-tec 33 Combi ErP | 2015–present |
| 47-077-03 | Duo-tec 40 Combi ErP | 2015–present |
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Your boiler has detected a general issue that is preventing it from firing up correctly, meaning you currently have no heating or hot water.
Your boiler has identified a flue sensor or ventilation issue that is preventing it from firing safely.
Your boiler has detected a general internal error that is preventing it from starting up correctly.
Your boiler has stopped working because it is unable to accurately measure the temperature of the water inside the system.
Your boiler has stopped working because the water pressure inside the heating system has dropped too low to operate safely.
Your boiler has detected that hot water is not moving around your heating system properly, so it has shut down to prevent itself from overheating.
Your boiler has detected that it is running too hot and has automatically shut down to prevent damage.
Your boiler is failing to light because it cannot detect a flame, meaning you currently have no heating or hot water.
Your boiler is unable to safely move air through its system, so it has shut down to prevent any unsafe conditions.
Your boiler has lost the ability to accurately measure the temperature of the water circulating to your radiators, so it has shut down as a precaution.
Your boiler is struggling to clear exhaust gases safely and has turned itself off to prevent a potential hazard.
Your boiler is currently unable to sense the temperature of your hot water properly, which means it has stopped heating your water to prevent it from getting too hot.
Your boiler has detected that it is overheating and has automatically switched itself off to prevent damage.
Your boiler has stopped working because the water pressure inside the system has dropped too low to operate safely.
Your boiler has detected that water is not moving around the system correctly, which is preventing it from heating your home safely.
Your boiler has detected that the temperature of the exhaust fumes leaving the flue is too high, so it has shut itself down to prevent damage or overheating.
Your boiler is failing to light because it cannot detect a flame, which is most often caused by a lack of gas supply or a temporary glitch in the ignition system.
Your boiler has stopped working because the mechanical fan that pushes waste gases outside is not responding or receiving power.
Your boiler is struggling to get water moving through the system properly before it attempts to light the burner.
BoilerFaultCodes