9 fault codes with plain-English explanations, severity ratings, DIY guidance, and repair cost estimates.
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Your boiler has detected an electrical problem and has shut itself down to prevent a fire or shock hazard.
Your boiler has detected that it has become dangerously overheated and has automatically shut itself down to prevent damage.
Your boiler has detected that the water inside the heating system has become dangerously hot and has shut itself down to prevent damage or overheating.
Your boiler has stopped working because it cannot detect a rise in temperature when it tries to heat your water, suggesting a sensor is failing to report its readings correctly.
Your boiler has lost the ability to measure its own water temperature, so it has safely shut down to prevent overheating.
Your boiler is struggling to read the temperature outside, which may cause it to run less efficiently or prevent the heating from adjusting correctly.
Your boiler is struggling to accurately measure the temperature of the water used for your taps and shower, which will likely result in a loss of hot water.
Your boiler has stopped working because the water pressure inside the system is too low to operate safely.
Your boiler has switched itself off because the water inside it is heating up much faster than it is moving away, preventing it from working as intended.
Not faults — these are normal operating states. Tap to expand.
BoilerFaultCodes