22 fault codes with plain-English explanations, severity ratings, DIY guidance, and repair cost estimates.
Replaced by: Mexico HE
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Your boiler's small pilot flame is failing to remain lit once you let go of the ignition knob, meaning the main safety mechanism is preventing it from heating your home.
Your boiler has successfully lit its internal pilot light, but it is failing to release the main supply of gas needed to heat your home.
Your boiler has automatically turned off because it got too hot, acting as a safety precaution to prevent damage.
Your boiler has detected that the water inside the system is getting too hot and has safely shut down to prevent damage.
Your boiler's electronic command center has encountered a serious internal error and has stopped working to prevent further damage.
Your boiler has detected an internal electrical fault and is preventing itself from lighting to keep you safe.
Your boiler has detected that the electrical supply connections are wired in the wrong way round, preventing it from starting safely.
Your boiler has stopped working because it cannot properly clear the exhaust gases from the system.
Your boiler has detected that it is getting dangerously hot and has automatically switched itself off to prevent damage or safety issues.
Your boiler's electronic control centre is experiencing a serious internal error and has stopped working to keep your home safe.
Your boiler has failed to ignite after several tries, meaning it has safely shut itself down because it cannot get a flame started.
Your boiler has lost the water pressure it needs to circulate heat, likely due to a slow leak somewhere in your radiators or pipes.
Your boiler is operating exactly as it should and is currently burning gas to provide heat or hot water.
Your boiler is failing to light because it cannot confirm that the internal fan is effectively clearing waste gases safely.
Your boiler is receiving power from the mains electricity, which is a normal status operation rather than a functional fault.
Your boiler is currently trying to light the burner and you are seeing the normal indicator for the ignition spark.
This light is part of the boiler's normal starting process and shows it is currently trying to light the burner.
Your boiler is currently trying to light the flame, but if the light continues to flash indefinitely, it means the burner has failed to ignite.
Your boiler has detected that a vital safety switch is stuck in the 'on' position, preventing the system from starting its safety checks.
Your boiler is failing to start because the internal fan is not spinning correctly or the control board cannot confirm it is working.
Your boiler has lost power to its main control board, which means the system cannot operate or provide heating and hot water.
Your boiler has detected that it is getting too hot and has automatically switched itself off to prevent damage or danger.
BoilerFaultCodes