29 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 getting too hot and has automatically switched itself off to prevent any damage.
Your boiler has detected that the exhaust gases leaving the unit are dangerously hot, so it has safely shut itself down to prevent damage.
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 struggling to detect the flow of water through the pipes because a sensor is sending an incorrect electrical signal.
Your boiler is experiencing a computer memory error related to your hot water settings and needs to be reconfigured by a professional.
Your boiler has attempted to restart itself too many times after a fault and has now locked itself out for safety, so it will no longer fire up.
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 water properly.
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 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 temperature gauge is misreading, which prevents it from heating your home because it doesn't know the current temperature of the water returning to the system.
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 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 lit and is automatically trying to restart itself to get your heating or hot water working again.
Your boiler is struggling to keep its internal flame lit and has safely shut down to prevent any issues.
Your boiler is struggling to move water through the system efficiently, causing it to overheat very quickly.
Your boiler is getting too hot inside its exhaust path, so it has automatically turned down its power to prevent any internal damage.
Your boiler is struggling to talk to your wireless thermostat, 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 is struggling to detect water temperature correctly, which is likely caused by a blocked system, loose wiring, or a faulty sensor prevented it from heating properly.
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 completely shut down with only a single dot visible on the display, meaning it has lost power or the main control board has turned off.
Your boiler is simply displaying a routine reminder that it has been a year since its last service.
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BoilerFaultCodes