25 fault codes with plain-English explanations, severity ratings, DIY guidance, and repair cost estimates.
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Your boiler is struggling to accurately measure your hot water temperature because one of its internal sensors has stopped working correctly.
Your boiler is temporarily unable to accurately measure the temperature of your hot water supply.
Your boiler has detected a false flame signal inside when the burner is supposed to be switched off, which prevents it from operating safely.
Your boiler has detected an issue with the domestic hot water temperature sensor or heat exchanger performance.
Your boiler has detected an issue related to the domestic hot water system or heat exchanger.
Your boiler has stopped working because an internal electrical fuse has blown, cutting off power to key components.
Your boiler has automatically shut down because the internal water temperature became dangerously high.
Your boiler has temporarily stopped working for safety reasons and needs to be manually reset to get it going again.
Your boiler has temporarily stopped working for safety reasons and needs to be reset.
Your boiler has temporarily stopped working as a safety precaution and needs to be reset.
Your boiler has temporarily stopped working as a safety precaution to prevent potential damage.
Your boiler has safely shut itself down due to a general safety lock-out, meaning it has stopped working until the underlying issue is resolved.
Your boiler has temporarily stopped working for safety reasons and needs to be reset.
Your boiler has temporarily shut itself down for safety reasons and stopped providing heating and hot water.
Your boiler has safely shut itself down due to a recurring internal safety lock-out.
Your boiler has safely shut itself down due to a general lockout fault that requires a professional engineer to diagnose and reset.
Your boiler has safely shut down and locked itself to prevent potential risks, meaning you currently have no heating or hot water.
Your boiler has completely stopped working and locked itself out for safety due to a persistent internal fault.
Your boiler has safely shut itself down due to a safety lock-out, meaning it needs to be manually reset or checked by a professional before it will work again.
Your boiler has completely lost electrical power and will not turn on.
Your boiler has temporarily stopped working because a sensor that monitors the temperature of the exhaust gases is reading an incorrect value or has failed.
Your boiler is temporarily locking out because the sensor that checks for the flame is not properly detecting it when the burner tries to ignite.
Your boiler has detected an issue with the condensate drain, which usually happens when the waste pipe outside becomes blocked or frozen.
Your boiler has temporarily stopped working because it has lost accurate track of the water temperature inside the system.
Your boiler has completely stopped working and locked itself out as a safety precaution.
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BoilerFaultCodes