18 fault codes with plain-English explanations, severity ratings, DIY guidance, and repair cost estimates.
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Your boiler has detected an issue with the fuel supply system, meaning it cannot ignite safely to provide heating or hot water.
Your boiler has lost the ability to accurately measure the temperature of the water circulating through your radiators, so it has shut down to prevent overheating.
Your boiler has detected a communication error with its exhaust sensor, causing it to shut down for safety reasons.
Your boiler is struggling to accurately read the temperature of the water returning to it, which prevents the system from heating your home properly.
Your boiler has detected that it has become dangerously hot and has automatically shut itself down to prevent damage or fire risk.
Your boiler has detected that water is not moving effectively around your heating system, which forces the boiler to shut down to prevent overheating.
Your boiler has detected that the flue gases are becoming too hot, causing the system to shut down for safety reasons.
Your boiler has stopped working because it cannot light the internal flame, which is likely due to the gas supply being cut off or the ignition failing to spark.
Your boiler has stopped working because it is failing to receive a consistent supply of gas or is struggling to ignite properly.
Your boiler has stopped working because it cannot detect that the internal fan, which is essential for safely exhausting gases, is running correctly.
Your boiler has stopped heating your home or water because it is failing to read the internal temperature correctly.
Your boiler has detected that the internal control board is not the correct version required for your specific model, preventing it from functioning safely.
Your boiler has lost the ability to accurately measure the temperature of the hot water inside it, so it has shut down to prevent overheating.
Your boiler has detected that it is overheating and has shut itself down to prevent internal damage.
Your boiler has stopped working because the water pressure inside the system has dropped too low to operate safely.
Your boiler has detected that water is not flowing around your heating system correctly, which prevents it from safely producing heat.
Your boiler has stopped working because it cannot detect a flame or is not receiving the gas supply needed to stay lit.
Your boiler has detected that the internal fan responsible for safely removing exhaust gases is not working correctly, so it has shut down to keep your home safe.
BoilerFaultCodes