36 fault codes with plain-English explanations, severity ratings, DIY guidance, and repair cost estimates.
Replaced by: Keston Heat 55 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 |
|---|---|---|
| 41-930-41 | Heat 55 | 2013–present |
Appliance names and production years are taken from the UK Product Characteristics Database (the SAP/SEDBUK register). Where a GC number is also printed in this model's own manufacturer manual, both sources were checked to agree.
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Your boiler has failed to light the flame, so it has safely shut itself down to prevent a build-up of unburnt gas.
Your boiler has detected that it is running much hotter than it should be and has automatically switched itself off to prevent overheating damage.
Your boiler has failed to start up or stay burning, so it has purposefully shut down to prevent gas from building up in the system.
Your boiler has detected a flame when it shouldn't be there, so it has shut itself down to ensure your safety.
Your boiler has stopped working because the water pressure inside the system has dropped too low.
Your boiler was running but the flame went out unexpectedly, so it has safely shut itself down to prevent any gas issues.
Your boiler has detected that the internal fan is not working correctly, which prevents it from operating safely.
Your boiler has stopped working because it is unable to accurately read the temperature of the water or the exhaust gases, forcing it to shut down for safety.
Your boiler is unable to read the temperature of the water returning to it, so it has safely shut down to prevent overheating.
Your boiler is struggling to detect the outdoor temperature, so it is defaulting to a standard operation mode rather than adjusting based on the weather conditions.
Your boiler has detected that hot and cold water pipes have been incorrectly connected to the system, meaning it cannot circulate heat properly.
Your boiler has lost the signal from the sensor that monitors your hot water tank temperature, meaning it cannot accurately control your hot water heating.
Your boiler has stopped heating because a connected external safety device, such as a fire alarm or ventilation sensor, has signaled it to shut down.
Your boiler's computer memory card is not communicating correctly, preventing the heating system from operating safely.
Your boiler is providing hot water to your taps as normal, but it is refusing to activate the central heating for your radiators.
Your boiler is still keeping your home warm with central heating, but it is not producing any hot water for your taps and showers.
Your boiler has lost all power and the control screen is completely blank, meaning it is currently unable to provide heating or hot water.
Your boiler is receiving an invalid or faulty electronic signal from an external control system, such as a building management controller or thermostat, preventing it from operating correctly.
Your boiler's internal memory chip is not communicating correctly with the main control board, which prevents the unit from starting or running reliably.
Your boiler is struggling to read the temperature of your hot water cylinder, which usually means it cannot properly tell when your water needs to be heated.
Your boiler has detected a flame when it shouldn't be there, so it has shut itself down to ensure your safety.
Your boiler has stopped operating because a safety device connected to the outside of the heating system has been triggered.
Your boiler has detected a flame when it should be turned off, so it has purposefully shut itself down to ensure your safety.
Your boiler has stopped working because it cannot properly clear exhaust gases, so it has shut down as a safety precaution to prevent dangerous fumes from building up.
Your boiler has safely shut down because the internal burner flame has unexpectedly gone out.
Your boiler has temporarily stopped working because a temperature sensor is failing to read the heat correctly, which is a safety measure to prevent overheating.
Your boiler has detected that the water is circulating in the wrong direction, which usually means some pipes were connected incorrectly or there is a major issue with the water pump.
Your boiler has temporarily stopped working because it has detected a problem with the sensor that monitors the temperature of the exhaust gases coming out of the flue.
Your boiler has stopped trying to start up because it cannot detect a flame to safely heat your home.
Your boiler is failing to operate because the electrical power it is receiving from your home is significantly lower than required.
Your boiler has stopped working because the water level inside the heating system has dropped too low.
Your boiler's outdoor weather sensor is failing to communicate properly, meaning it cannot automatically adjust your heating based on the outside temperature.
Your boiler has detected that it is running too hot and has automatically turned itself off to prevent damage.
Your boiler's main electronic brain has experienced a critical internal error and needs to be replaced or reconfigured by a professional.
Your boiler is temporarily unable to accurately measure the temperature of the water returning to it, so it has safely shut down to prevent any issues.
Your boiler has temporarily locked itself out because the reset button has been pressed too many times in a short period.
BoilerFaultCodes