17 fault codes with plain-English explanations, severity ratings, DIY guidance, and repair cost estimates.
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Your boiler is trying to start but cannot get the flame to stay lit, so it has safely shut itself down to avoid wasting fuel.
Your boiler has detected that water is not flowing through the system correctly, so it has shut down to protect itself from overheating.
Your boiler has automatically turned itself off because the water inside it has become dangerously hot.
Your boiler has stopped working because it couldn't light the burner to create heat, most likely due to an issue with its gas supply.
Your boiler has stopped working because the water pressure is too low for it to operate safely.
Your boiler has shut down because it has detected it is getting too hot, which is usually caused by water not circulating properly through the system.
Your boiler is struggling to keep a flame lit during its normal cycle, causing it to shut down for safety.
Your boiler has stopped working because there is not enough water inside the system to operate safely.
Your boiler has stopped working because the flame has failed to stay lit or is not being detected during operation.
Your boiler has detected an issue with the air flow or ventilation, causing it to stop running as a safety precaution.
Your boiler's main burner is not firing correctly, which means your heating and hot water will not work.
Your boiler has detected that it is getting dangerously hot even while it isn't supposed to be running, causing it to shut down for safety.
Your boiler has detected a problem with how it clears exhaust fumes, causing it to shut down for safety.
Your boiler has detected that there is not enough water pressure flowing through the system to heat your home safely.
Your boiler has detected that it is running too hot and has automatically shut itself down to prevent damage.
Your boiler tried to light the burner but couldn't detect a flame, causing it to stop for safety.
Your boiler's main internal computer has detected a problem while trying to ignite and has shut itself down for safety.
Not faults — these are normal operating states. Tap to expand.
BoilerFaultCodes