9 fault codes with plain-English explanations, severity ratings, DIY guidance, and repair cost estimates.
Replaced by: Bluehelix Tech
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Your boiler is failing to detect that you have turned on a hot water tap, meaning it won't fire up to heat the water.
Your boiler has stopped providing hot water because it is struggling to read or regulate the temperature from its water heating sensor.
Your boiler has stopped working because it cannot properly read the water temperature or it has detected that it is running too hot.
Your boiler's electronic brain is malfunctioning and cannot correctly process its startup sequence, meaning it will currently fail to provide heating or hot water.
Your boiler is perfectly fine, it is simply pausing for a few minutes before starting up again to protect its parts.
Your boiler has stopped working because it is unable to accurately detect the water pressure or temperature, preventing it from safely heating your home or water.
Your boiler has stopped working because it has detected an issue with its internal temperature sensors or water pressure levels, preventing it from safely heating your home.
Your boiler has stopped working because the connection to the control system is failing to receive the necessary electrical power.
Your boiler is failing to start because it cannot confirm that the internal fan is operating correctly, preventing the safe clearing of exhaust gases.
Not faults — these are normal operating states. Tap to expand.
BoilerFaultCodes