9 fault codes with plain-English explanations, severity ratings, DIY guidance, and repair cost estimates.
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Your boiler has failed to ignite because it is not receiving gas or has detected an issue with the internal airflow, meaning you currently have no heating or hot water.
Your boiler is failing to circulate water properly because it cannot sense the flow it needs to heat your home.
Your boiler is struggling to clear air and gases away properly because the exhaust pipe or an internal sensor is blocked with debris.
Your boiler has stopped working because the water pressure inside the system has dropped too low.
Your boiler has lost connection to its optional remote control unit, preventing it from receiving temperature commands.
Your boiler is having trouble measuring the temperature of your hot water, which usually means it will stop producing hot water properly.
Your boiler is struggling to read its own internal water temperature, so it has shut down to prevent overheating.
Your boiler has detected that it is running too hot and has automatically shut down to prevent damage.
Your boiler's internal computer has developed an error and can no longer control the heating system correctly.
BoilerFaultCodes