13 fault codes with plain-English explanations, severity ratings, DIY guidance, and repair cost estimates.
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Your boiler has automatically shut down because the water inside it has become dangerously hot.
Your boiler has stopped working because it cannot safely confirm that exhaust gases are clearing properly.
Your boiler's heating temperature sensor has failed, which means the system cannot accurately measure how hot the water is getting.
Your boiler is struggling to accurately measure the temperature of your hot water because a sensor is faulty.
Your boiler's main electronic brain is failing to control the ignition and operation properly, which usually results in a complete shutdown to keep your home safe.
Your boiler has detected an issue with the sensor that measures the temperature of the exhaust gases leaving the flue.
Your boiler has detected that water isn't flowing properly through its internal heating pipes, so it has safely shut down to prevent damage.
Your boiler has detected that water is not flowing properly through its internal heating system, meaning it cannot circulate heat safely.
Your boiler has safely shut down because a sensor detected that the temperature of the exhaust gases leaving through the flue is too high.
Your boiler is failing to start up because it cannot get the flame to ignite.
Your boiler is not receiving any electrical power, which stops it from working entirely.
Your boiler is not receiving any electrical power or the main control board has failed, causing the entire system to shut down completely.
Your boiler has shut itself down safely because it detected that internal temperatures became too high.
BoilerFaultCodes