19 fault codes with plain-English explanations, severity ratings, DIY guidance, and repair cost estimates.
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Your boiler is failing to light the flame, which means it cannot produce any hot water or heating.
Your boiler has detected heat or a flame inside the unit when it should be turned off, which is a significant safety precaution.
Your boiler has automatically shut down because the internal water temperature reached an unsafely high limit.
Your boiler has detected an issue with the removal of exhaust gases, so it has safely shut down to prevent any harmful fumes from escaping into your home.
Your boiler has stopped working because the internal fan responsible for safely pushing exhaust gases outside is not operating correctly.
Your boiler is failing to light the burner despite several attempts, meaning it currently cannot provide heating or hot water.
Your boiler has lost the signal from the sensor that monitors the water temperature, meaning it cannot tell how hot the water is or if it needs to heat up.
Your boiler is struggling to clear exhaust fumes properly, which means it has safely shut down to prevent the build-up of dangerous gases.
Your boiler is struggling to detect the flow of water through the system, which means it has stopped providing heating and hot water to protect itself.
Your boiler is having trouble measuring the temperature of the water returning to it, so it has safely shut down to prevent overheating.
Your boiler has detected a problem with the sensor that monitors the temperature of the gases leaving your flue, causing it to shut down for safety reasons.
Your boiler is not detecting the flow of water, which prevents it from starting up correctly to provide heating or hot water.
Your boiler is struggling to clear exhaust gases, so it has safely shut down to prevent any unsafe buildup.
Your boiler has detected that the electricity supply coming from your wall socket is too weak to operate the internal components safely.
Your boiler has detected an issue with the quality of your home's electrical supply, meaning the power entering the unit is inconsistent.
Your boiler has stopped working because the water pressure inside your heating system has dropped too low to operate safely.
Your boiler has detected that the water pressure inside your heating system is either too high or too low for it to operate safely.
Your boiler is struggling to detect the flow of water because a sensor inside the unit is providing an incorrect reading, which prevents it from safely heating your home or water.
Your boiler has stopped working because it has lost connection to a key internal sensor or control board.
BoilerFaultCodes