57 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 the flame is not catching, so it has shut down for safety to prevent gas from building up.
Your boiler has detected that it is running much too hot and has automatically shut itself down to prevent damage or fire risk.
Your boiler has detected that the exhaust gases leaving the system are dangerously hot and has shut itself down to prevent damage or overheating.
Your boiler has lost the secure electrical connection required to tell the gas supply when to turn on, meaning it cannot ignite to provide heat or hot water.
Your boiler is failing to register the flow of water because of a faulty electronic sensor, meaning it has switched itself off to prevent overheating.
Your boiler has detected that its electrical components are not connected correctly, preventing it from starting up safely.
Your boiler is currently in a manual testing mode used by engineers to check emissions, which prevents it from heating your home normally.
Your boiler has attempted to restart itself too many times after encountering previous errors and has now locked itself out as a safety precaution.
Your boiler has stopped working because the water pressure inside your heating system has dropped too low to operate safely.
Your boiler is struggling to detect the temperature of your hot water cylinder, meaning it cannot reliably heat your water.
Your boiler’s internal computer is confused about how it is set up and is unable to operate because it detects a mismatch between its configuration settings and the hardware it sees.
Your boiler has stopped working because it cannot communicate with the internal fan responsible for venting exhaust gases.
Your boiler is detecting a flame when it shouldn't be, which is a safety mechanism preventing it from starting up to protect your home.
Your boiler is struggling to accurately read the temperature of the water returning to it, which prevents it from heating your home or water reliably.
Your boiler has detected that one of the buttons on its control panel is permanently pressed or jammed, which is preventing the system from operating normally.
Your boiler has detected that the water inside it is heating up much faster than normal, which suggests a blockage or lack of water flow preventing the system from cooling down.
Your boiler has detected an issue with the sensor that monitors exhaust gases and has shut down to keep you safe.
Your boiler has lost its connection to your digital wall controller, meaning it no longer knows when to turn the heating on or off.
Your boiler is failing to start because it is not receiving enough consistent electricity from your home's power supply.
Your boiler is trying to stay lit but the flame keeps going out, so it will keep trying to restart itself until it locks out.
Your boiler is struggling to keep its internal flame lit while it is running.
Your boiler is struggling to circulate water properly and has slowed down its heating to prevent any internal damage.
Your boiler communication link is broken, meaning it cannot receive the signal from your room thermostat to tell it to turn the heating on.
Your boiler is currently running at a lower power because it has detected that the exhaust gases are getting too hot, serving as a warning before it shuts itself down completely.
Your boiler has sensed that the water circulating back into it is too hot, causing it to shut down to prevent damage to its internal components.
Your boiler is struggling to talk to the wireless thermostat controller, meaning it doesn't know when to turn your heating on or off.
Your boiler's water circulation pump has stopped working, which means the system cannot move hot water to your radiators or taps.
Your boiler is struggling because there is trapped air inside the system, which is preventing hot water from circulating properly to your radiators.
Your boiler has detected that hot water is flowing the wrong way or in a way that suggests a blockage, causing it to shut down to prevent internal damage.
Your boiler is failing to heat up the water inside it, so it has shut down to prevent damage to its internal parts.
Your boiler is struggling to accurately measure the temperature of the water inside it, so it has shut down to prevent overheating.
Your boiler is having trouble measuring water temperatures, so it has stopped working to prevent any damage to the internal system.
Your boiler is trying to start but cannot light the internal flame, so it has shut down as a safety precaution.
Your boiler has detected that it is getting too hot and has automatically switched itself off to prevent any damage or safety issues.
Your boiler has detected that the exhaust gases are getting too hot and has safely shut itself down to prevent damage.
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 potential overheating.
Your boiler has lost the ability to accurately measure the temperature of your hot water, which means it will stop heating the water to prevent it from getting too hot.
Your boiler has failed to light the flame after several attempts and has locked itself out for safety.
Your boiler has stopped working because the water pressure inside the heating system has dropped too low.
Your boiler has stopped working because the water pressure inside your heating system has dropped too low.
Your boiler has lost the ability to accurately measure the temperature of the water returning to it, so it has shut down to prevent potential overheating.
Your boiler has stopped working because the mechanical fan responsible for venting combustion gases safely out of your home is not spinning correctly.
Your boiler has detected a flame inside the unit when it should be switched off, and it has safely locked itself to prevent an unsafe situation.
Your boiler has detected an error with the digital control panel, which is preventing it from functioning correctly.
Your boiler has lost its digital connection to the wall-mounted thermostat, so it no longer knows when to turn your heating on or off.
Your boiler has detected a flame signal even though it is not trying to heat your home, which is a safety concern that requires professional attention.
Your boiler has detected that the flame inside has gone out unexpectedly or failed to light, so it has safely shut down to prevent gas from building up.
Your boiler is repeatedly trying to start but keeps failing to maintain a flame, so it has safely shut down to prevent gas from building up.
Your boiler is having trouble controlling the flow of gas necessary to heat your home, so it has safely shut down to prevent incorrect operation.
Your boiler is detecting an issue with the electricity supply entering the unit, which is preventing it from operating correctly.
Your boiler has detected an electrical fault within the ignition system, which is preventing it from safely lighting the flame.
Your boiler has detected an internal issue with the part that controls the gas supply, meaning it has safely shut down to prevent incorrect operation.
Your boiler has detected that fumes are not escaping properly through the exhaust pipe, meaning it has shut down to prevent the buildup of dangerous gases inside your home.
Your boiler has reached its scheduled annual service interval and is simply reminding you that it is time for a routine professional check-up.
Your boiler is currently in a manual testing mode used by engineers to check performance, rather than having a mechanical breakdown.
Your boiler's wireless controller has momentarily lost contact with the unit, usually because the boiler was switched off at the mains.
Your boiler is simply reminding you that its annual service is now due to ensure it continues to run safely and efficiently.
BoilerFaultCodes