16 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, which means it cannot accurately measure how hot the water is and has stopped working for safety.
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 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 an issue with the gas flow or internal pressure tubing, resulting in a shutdown to keep your home safe.
Your boiler has failed to ignite and light the flame successfully, which usually points to an issue with the spark ignition system.
Your boiler has temporarily stopped working because it is not detecting a steady flame, which usually points to a gas supply issue or a sensor problem.
Your boiler has temporarily shut down because it detected that the internal temperature got too high.
Your boiler has detected an issue with the internal wiring connection to the main fan, which stops the system from operating safely.
Your boiler has detected an issue with its temperature sensors or a potential blockage, so it has safely stopped working to prevent damage.
BoilerFaultCodes