5 fault codes with plain-English explanations, severity ratings, DIY guidance, and repair cost estimates.
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Your boiler has stopped working because the mechanical component responsible for circulating air and exhausting combustion gases is not receiving power or has failed.
Your boiler has stopped working because it can no longer accurately read the temperature of the exhaust chimney, meaning it has shut down as a safety precaution.
The computer that controls your boiler is experiencing an internal error, which means the system cannot safely start or regulate your heating and hot water.
Your boiler has lost the ability to measure the temperature of the water leaving it, which means it has safely shut down to prevent overheating.
Your boiler has lost the ability to measure the temperature of the water returning to it, so it has safely shut down to prevent overheating.
Not faults — these are normal operating states. Tap to expand.
BoilerFaultCodes