8 fault codes with plain-English explanations, severity ratings, DIY guidance, and repair cost estimates.
Replaced by: Linea One
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Your boiler has failed to light its burner, which means it cannot produce any heating or hot water for your home.
Your boiler has detected that it is overheating and has automatically shut itself down to prevent any damage or safety issues.
Your boiler is struggling to clear exhaust gases because the internal fan that pushes air out through the flue has stopped spinning correctly.
Your boiler is currently performing a brief automatic system check to ensure everything is initialized correctly before starting up.
Your boiler has detected that the water inside the system is getting far too hot, which has caused it to shut down to prevent damage.
Your boiler has sensed that the water returning to it from your radiators is too hot, causing it to shut down to prevent damage to the system.
Your boiler has detected an issue with the sensor that monitors exhaust gases or internal heat, forcing it to shut down for safety.
Your boiler has detected that the temperature safety sensor for your underfloor heating system has been triggered, causing it to shut down to prevent overheating.
Not faults — these are normal operating states. Tap to expand.
BoilerFaultCodes