15 fault codes with plain-English explanations, severity ratings, DIY guidance, and repair cost estimates.
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Your boiler is trying to start up and even lighting the gas, but it fails to recognise that the flame has actually caught, so it safely shuts down again.
Your boiler has temporarily stopped because it cannot detect the flame needed to keep it running safely.
Your boiler has detected an issue with the valve that controls the flow of gas, meaning it cannot ignite safely.
Your boiler has failed to light properly on its first attempt and safely shut down to prevent gas from building up.
Your boiler has detected a potential safety issue with its internal gas valve or flame sensor, so it has safely locked itself out to prevent operation.
Your boiler has temporarily stopped working because it cannot properly read its internal temperature sensors.
Your boiler has automatically shut down because the internal water temperature reached an unsafe level.
Your boiler has automatically shut down because it detected that the internal water temperature became dangerously high.
Your boiler has temporarily stopped because the water returning from your radiators is hotter than it should be.
Your boiler has automatically shut down because the water inside it has become dangerously hot, exceeding safe temperature limits.
Your boiler's main electronic control brain has suffered an internal fault and has safely shut down to prevent damage.
Your boiler has temporarily stopped working because it cannot detect the correct airflow through the internal fan.
Your boiler has experienced a safety lockout and then suffered a sudden loss of power or mains voltage interruption.
Your boiler has detected an internal computer error and has shut down safely to prevent any further issues.
Your boiler has detected an unspecified general fault and has safely locked itself out to prevent any issues.
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BoilerFaultCodes