24 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 too hot and has automatically shut itself down to prevent any damage or safety risks.
Your boiler has detected that the exhaust gases are becoming dangerously hot, so it has automatically shut itself down to prevent damage or safety hazards.
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 is having trouble accurately measuring the temperature of the water used for your taps and shower.
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, which means it may fail to heat your taps or shower correctly.
Your boiler has detected an internal communication or connection error within its control system, preventing it from operating safely.
Your boiler has stopped working because it cannot communicate with the internal fan that clears exhaust gases from the system.
Your boiler has detected heat or fire inside the unit even when it hasn't turned the gas on, so it has shut down to keep your home safe.
Your boiler's control panel detects that one of the buttons is jammed or being held down permanently, which is stopping the system from operating normally.
Your boiler has detected an abnormally fast rise in temperature and has shut itself down to prevent internal damage.
Your boiler is struggling to pump water around your heating system fast enough, causing it to overheat and shut down for safety.
Your boiler has detected a faulty reading from the temperature sensor measuring your exhaust gases, so it has safely shut down to prevent potential overheating.
Your boiler has lost its digital connection to your room thermostat, meaning it no longer knows when to turn the heating on or off.
Your boiler is failing to start because it isn't receiving enough electricity from your home's power supply.
Your boiler is struggling to keep the flame alight once it has started, so it is automatically pausing to try again safely.
Your boiler has lost the signal that confirms a flame is burning, so it has shut down for safety.
Your boiler has detected a safety concern and has automatically shut itself down to prevent any potential damage or risk.
Your boiler is receiving an unusual signal from an optional outdoor temperature sensor, causing it to restrict its heating output to protect the system.
Your boiler is still working but cannot reach its full power, meaning your radiators might not get as hot as they should.
Your boiler has lost its wireless connection with your thermostat or remote control, meaning they can no longer talk to each other to manage your heating.
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BoilerFaultCodes