12 fault codes with plain-English explanations, severity ratings, DIY guidance, and repair cost estimates.
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Your boiler has detected an issue with one of its temperature sensors and is automatically adjusting its power to keep things safe, which may temporarily affect your heating or hot water.
Your boiler is trying to start up, but the gas isn't staying alight, so it has safely locked itself out.
Your boiler is letting you know that the internal fan is operating correctly and running at the right speed.
Your boiler has lost track of how hot the water inside the heating system is because a temperature sensor has failed.
Your boiler is struggling to accurately measure your hot water temperature because a sensor is faulty.
Your boiler has temporarily stopped working because it has detected an issue with the sensor that measures the temperature of the exhaust gases coming from the flue.
Your boiler has automatically shut down because it detected that the internal water temperature became dangerously high.
Your boiler has temporarily stopped working because the water pressure inside the system has dropped too low.
Your boiler has detected an issue with the internal water pump, which means it cannot circulate water properly to provide heating or hot water.
Your boiler has temporarily stopped working because it has detected that the exhaust gases coming from the flue are too hot.
Your boiler has temporarily stopped working because it cannot detect a steady flame, which usually points to an issue with your gas supply or the way the boiler is igniting.
Your boiler has stopped working because it cannot detect that the internal fan, which safely removes combustion gases, is operating properly.
BoilerFaultCodes