20 fault codes with plain-English explanations, severity ratings, DIY guidance, and repair cost estimates.
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Your boiler has detected that the water is getting too hot too quickly, likely due to a circulation problem or a sensor error.
Your boiler has stopped working because the water pressure in the system has dropped too low.
Your boiler has detected that the water pressure is too low to operate safely and has shut down to prevent damage.
Your boiler has encountered a technical communication or internal sensor error and has stopped working to protect itself.
Your boiler has tried to light several times but cannot confirm that a flame has stayed lit, so it has shut down for safety.
Your boiler has detected a flame when there shouldn't be one, or the sensor incorrectly thinks a fire is still burning after the gas has been turned off.
Your boiler has shut down because its internal temperature has gotten too high and a safety switch has tripped to prevent damage.
Your boiler has stopped working because the fan that clears out exhaust fumes is not spinning or communicating correctly with the system.
Your boiler has detected that the water pressure is either too low or the sensor that monitors it has stopped working.
Your boiler has detected that the water pressure is too low or a sensor that monitors the water level is failing, preventing the system from heating up.
Your boiler's internal sensor that monitors water pressure has developed a fault, preventing the system from operating safely.
Your boiler has detected an issue with its incoming electrical power supply, meaning the internal computer cannot function correctly.
Your boiler's temperature sensor for hot water has stopped working correctly, meaning your taps may only provide cold or lukewarm water.
Your boiler has detected an electrical issue with the part that controls the gas flame size, meaning it cannot heat your water or radiators reliably.
Your boiler has detected an issue with the sensor that monitors the temperature of the water in your central heating system.
Your boiler has detected that the water temperature is too high or is not circulating correctly, causing it to shut down for safety.
Your boiler has detected an issue with how it burns gas and has shut down as a safety precaution to prevent dangerous fumes.
Your boiler has detected that waste gases cannot properly escape through the exhaust pipe, often due to a blockage or a faulty safety sensor.
Your boiler has shut down because the internal exhaust gases have reached a dangerously high temperature, indicating a potential safety risk or a severe internal blockage.
Your boiler has detected that the main part responsible for heating your water is becoming blocked or dirty, which is preventing it from working efficiently.
BoilerFaultCodes