10 fault codes with plain-English explanations, severity ratings, DIY guidance, and repair cost estimates.
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Your boiler's temperature sensor for the heating system has developed a fault, meaning the boiler can no longer monitor how hot the water is.
Your boiler has detected a problem with the sensor that monitors the temperature of the exhaust gases, causing the system to shut down for safety.
Your boiler's hot water sensor has developed a fault, meaning the system cannot accurately measure the temperature of the water coming out of your taps and has stopped providing hot water to keep you safe.
Your boiler has become too hot and has shut itself down as a safety precaution to prevent damage.
Your boiler has stopped working because the water pressure in the system has dropped too low.
Your boiler has detected that hot water isn't moving through the system properly, which usually means it is overheating and has shut down as a safety precaution.
Your boiler has shut down because the exhaust gases have reached a temperature that is too high, or the safety sensor that monitors them has detected a fault.
Your boiler is failing to light the gas or stay lit, meaning your heating and hot water have stopped working.
Your boiler has stopped working because the fan that clears out exhaust gases is not spinning or communicating correctly with the main control board.
Your boiler has detected that water is not circulating correctly through the system before the burner ignites, often due to a blockage or trapped air.
BoilerFaultCodes