14 fault codes with plain-English explanations, severity ratings, DIY guidance, and repair cost estimates.
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Your boiler has lost track of how hot the water inside the heating system is because a temperature sensor has failed.
Your boiler's flue sensor is detecting a fault, meaning the system cannot accurately monitor the temperature of the exhaust gases, so it has safely shut down to prevent damage.
Your boiler is struggling to detect the temperature of the water it is trying to heat, so it has shut down to prevent overheating.
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 that water is not flowing properly around your heating system, so it has safely shut down to prevent overheating.
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.
Your boiler is struggling to get water moving around the system correctly before it attempts to fire up.
Your boiler has detected that the water pump is running continuously or incorrectly, which usually points to a control or circulation issue.
Your boiler is temporarily lowering its flame to keep the water at the correct temperature without overheating.
Your boiler is trying to start up and light the flame, but it is failing to stay on after a few seconds.
Your boiler's internal fan is running and operating at the correct speed to safely expel combustion gases.
BoilerFaultCodes