28 fault codes with plain-English explanations, severity ratings, DIY guidance, and repair cost estimates.
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The boiler is trying to start up but cannot light the gas or confirm that a flame has stayed lit.
Your boiler has become too hot and has switched itself off as a safety precaution to prevent damage.
Your boiler has detected that the exhaust gases are becoming too hot and has shut down as a safety precaution to prevent internal damage.
Your boiler has identified an electrical communication problem with the gas flow controller, preventing the burner from lighting safely.
Your boiler has stopped working because it cannot correctly measure the temperature of the water being sent to your radiators.
Your boiler has detected an issue with the sensor that monitors hot water temperature, meaning your taps and shower may not heat up correctly.
Your boiler has been manually reset too many times in a short period and has now locked itself for safety to prevent further issues.
Your boiler has detected that the water pressure in the system is too low for it to operate safely.
Your boiler is having trouble measuring the temperature of the cold water entering the system, which can prevent your hot water from reaching the right temperature.
Your boiler's internal computer is confused about how the pipes and water flow are set up, preventing it from running safely.
Your boiler has detected an issue with its internal fan, which means it cannot safely clear exhaust fumes and has shut down to protect you.
Your boiler thinks there is a flame burning even when there shouldn't be, which is preventing it from starting safely.
Your boiler has stopped working because it cannot correctly measure the temperature of the water coming back from your radiators.
One of the buttons on your boiler's control panel has become stuck, preventing the unit from operating correctly.
Your boiler has detected an issue with the sensor that monitors exhaust gases, and as a safety precaution, it has stopped running to prevent potential overheating or incorrect ventilation.
Your boiler has lost its connection to the external controller or room thermostat, meaning it no longer knows when to switch your heating on or off.
Your boiler has detected that the incoming electricity supply is too weak or unstable for it to function safely.
Your boiler is struggling to keep the burner lit, causing it to shut down and attempt to restart itself repeatedly.
Your boiler is struggling to stay lit because it cannot confirm that the internal burner flame is burning steadily.
Your boiler is struggling to move water through the system efficiently, causing a large temperature difference between the water leaving and returning to the unit.
Your boiler is running too hot because it is struggling to vent exhaust gases, so it has automatically turned its power down to prevent overheating.
Your boiler has detected that the water returning from your radiators is too hot, causing it to shut down for safety to prevent damage to the system.
Your boiler has lost its wireless connection to your room thermostat, meaning it doesn't know when to turn your heating on or off.
Your boiler's water circulation pump has stopped working, meaning the system cannot move hot water to your radiators or taps.
Your boiler is struggling to circulate water properly, likely because there is trapped air in the system or a blockage preventing the water from flowing as it should.
Your boiler is confused because it detects that the water returning to the system is hotter than the water leaving it, which shouldn't happen during normal operation.
Your boiler is having trouble measuring the temperature of the water moving inside it, so it has safely stopped working to prevent overheating.
Your boiler is struggling to accurately measure the temperature of the water circulating through your heating system, so it has stopped working to prevent potential damage.
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BoilerFaultCodes