35 fault codes with plain-English explanations, severity ratings, DIY guidance, and repair cost estimates.
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Your boiler is failing to light because it cannot detect a flame, meaning you currently have no heating or hot water.
Your boiler has detected that it is dangerously hot and has shut itself down to prevent damage or overheating.
Your boiler has detected that it cannot safely remove waste gases outside, so it has stopped working to prevent a buildup of harmful fumes in your home.
Your boiler is failing to stay lit because it cannot draw in enough air or push out exhaust fumes correctly, which has caused it to shut down for safety.
Your boiler has detected that the exhaust gases are getting too hot, likely because the vent that carries them outside is blocked or damaged.
Your boiler has detected an issue with the ventilation system that clears away exhaust fumes, so it has shut itself down to keep you safe.
Your boiler's central control computer is not functioning correctly, meaning the system has stopped to prevent unsafe operation.
Your boiler has failed to light the flame needed to produce heat and has safely shut itself down as a precaution.
Your boiler has detected a flame inside when it should be turned off, which is a significant safety precaution that prevents the unit from starting.
Your boiler has detected that the exhaust gases are becoming dangerously hot and has shut itself down to prevent damage or fire risk.
Your boiler has detected an issue with its exhaust system multiple times today and has locked itself out to keep your home safe.
Your boiler is not safely venting exhaust gases because the motorized fan is failing to run at the necessary speed.
Your boiler has detected that the exhaust gases are becoming dangerously hot, so it has shut itself down to prevent damage.
Your boiler is struggling to detect the flow of water through the system, which is preventing it from heating your home or water.
Your boiler is struggling to accurately monitor the temperature of the water returning to it, so it has stopped working as a safety precaution until the faulty sensor is replaced.
Your boiler is struggling to detect the temperature of your hot water supply, so it has safely stopped heating your taps to prevent any issues.
Your boiler has detected a problem with a sensor that monitors the temperature of the gases leaving your flue, causing it to shut down for safety.
Your boiler is struggling to detect the flow of water through the system, which means it has safely shut down to prevent overheating.
Your boiler's fan system is not responding correctly, which prevents it from safely venting exhaust gases and means your heating and hot water will stop working.
Your boiler has stopped because the flame inside it has unexpectedly gone out while it was trying to heat your water or home.
Your boiler has lost its ability to accurately measure the water temperature, so it has safely shut down to prevent overheating.
Your boiler is struggling to read its own temperature because a connection or a heat-sensing probe has developed a fault, causing it to shut down to prevent potential damage.
Your boiler is unable to measure the temperature of your hot water supply, so it has safely shut down to prevent overheating.
Your boiler has detected a communication error with its exhaust monitoring system, causing it to shut down for safety reasons.
Your boiler is failing to operate because the electricity supply feeding it is too low to keep the system running correctly.
Your boiler is struggling because the electricity supply coming from your wall socket isn't stable enough for the machine to operate safely.
Your boiler has stopped working because the water pressure inside the heating system has dropped too low to operate correctly.
Your boiler has identified a problem with the internal safety sensors that monitor the flame, causing it to shut down to prevent unsafe operation.
Your boiler has lost the signal from the sensor that monitors your outdoor temperature, so it is using a default setting to keep your home warm instead.
Your boiler has detected that the water pressure inside the heating system is too high and has shut itself down to prevent damage.
Your boiler is struggling to read its own internal temperatures because a temperature sensor is either loose or broken, so it has shut down to prevent damage.
Your boiler has detected that the water temperature is reading differently at two different points, meaning it has safely shut down to prevent overheating or inefficient operation.
Your boiler has detected that the water inside the unit is getting too hot, so it has safely shut itself down to prevent damage.
Your boiler has lost the ability to detect its own water level because a communication wire or sensor has come loose or stopped working.
Your boiler has detected a problem with the internal mechanism that controls the gas supply, meaning it has safely shut itself down to prevent unsafe operation.
BoilerFaultCodes