19 fault codes with plain-English explanations, severity ratings, DIY guidance, and repair cost estimates.
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Your boiler is trying to start up but is failing to light the burner, which means you currently have no heating or hot water.
Your boiler is struggling to clear exhaust gases properly, so it has safely shut itself down to prevent any risk.
Your boiler is having trouble managing the air it needs to burn gas safely, so it has shut itself down to prevent any issues.
Your boiler has detected that it is running too hot and has automatically shut itself down to prevent damage or safety risks.
Your boiler has detected that it is getting too hot and has automatically shut itself down to prevent any damage or safety issues.
Your boiler's temperature sensor is failing to provide a reading, so the system has shut down to prevent overheating.
Your boiler is struggling to detect the temperature of your hot water supply, so it has safely shut down to prevent overheating.
Your boiler is failing to read the temperature of the water returning to it, which means it cannot safely manage your heating and has shut down as a precaution.
Your boiler is struggling to accurately detect the water pressure inside the system, which is preventing it from firing up safely.
Your boiler's internal computer chips are failing to talk to each other, preventing the system from running safely.
Your boiler's electronic control panel is not 'talking' to the main brain of the system, meaning the boiler has shut down for safety.
Your boiler's internal computer is experiencing a communication error, meaning it can no longer safely control the heating system.
Your boiler is struggling to control its internal gas supply, which prevents it from igniting safely.
Your boiler is having trouble controlling the automatic gas supply, which means it will stop the system to keep you safe and cannot produce heat or hot water.
Your boiler is failing to detect a flame, so it has shut itself down to keep your home safe.
Your boiler has detected that the incoming electricity supply is not strong enough to run it safely, causing the system to shut down.
Your boiler has detected that a temperature sensor has come loose from the pipe it monitors, meaning the system can no longer accurately read the water temperature.
Your boiler's electronic control parts are unable to communicate with each other, causing the system to shut down for safety.
Your boiler has stopped working because the water pressure inside the system has dropped too low to operate safely.
BoilerFaultCodes