25 fault codes with plain-English explanations, severity ratings, DIY guidance, and repair cost estimates.
Replaced by: Advance Plus 2
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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 |
|---|---|---|
| 47-583-35 | Advance Plus 25C ErP | 2015–present |
| 47-583-36 | Advance Plus 30C ErP | 2015–present |
| 47-583-37 | Advance Plus 35C ErP | 2015–present |
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Your boiler is trying to start but failing to light the flame, so it has shut down as a safety precaution.
Your boiler has detected that it is running too hot and has automatically shut itself down to prevent damage.
Your boiler has detected a general internal fault that prevents it from operating and has shut itself down as a safety precaution.
Your boiler has detected that there is not enough water circulating inside the system to operate safely.
Your boiler has detected an issue with the internal ventilation system that prevents it from starting safely.
Your boiler is struggling to accurately measure its own internal temperature because a sensor is sending incorrect information, which prevents the heating from turning on.
Your boiler is struggling to accurately detect the temperature of your hot water, which means the hot tap may not work correctly or may run cold.
Your boiler is struggling to read the outside temperature, so it has reverted to a safe mode to prevent heating your home to the wrong temperature.
Your boiler has detected an issue with the sensor that monitors the temperature of the gases leaving your flue, causing it to shut down for safety.
Your boiler has detected that the temperature of the exhaust gases leaving the unit is too high and has safely shut down to prevent damage.
Your boiler is failing to light the flame or keep it lit, so it has purposefully shut itself down for your safety.
Your boiler has stopped working because it cannot move the hot water around your system, likely due to a stuck pump or because the system is overheating.
Your boiler has failed to light the flame needed to heat your home and has safely shut itself down as a precaution.
Your boiler has detected that it is overheating and has shut itself down to prevent any damage or safety hazards.
Your boiler has stopped working correctly because the system has encountered a general safety error and has shut itself down to prevent damage.
Your boiler is struggling to detect the water flowing through it, which is likely caused by low system pressure.
Your boiler has detected an issue with the internal fan that pushes exhaust gases out of your home, so it has safely shut itself down to prevent operation.
Your boiler is struggling to accurately measure the temperature of the water used for your radiators, which has caused it to stop working to avoid potential damage.
Your boiler is struggling to accurately measure the temperature of the hot water it provides, which has caused it to stop heating your water to prevent overheating.
Your boiler is struggling because it has lost the signal from the weather sensor installed outside your home.
Your boiler has detected an issue with the sensor that monitors the temperature of the exhaust fumes, meaning the system has shut down as a safety precaution.
Your boiler has detected that the exhaust gases are getting too hot, so it has safely shut itself down to prevent any damage.
Your boiler has detected that it is dangerously overheating and has automatically shut down to prevent damage.
Your boiler has detected that the water pressure in your heating system has dropped too low and needs to be topped up to function correctly.
Your boiler has detected that the water inside the unit is getting too hot while it is trying to heat your tap water, so it has shut down to prevent damage.
Not faults — these are normal operating states. Tap to expand.
BoilerFaultCodes