20 fault codes with plain-English explanations, severity ratings, DIY guidance, and repair cost estimates.
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Your boiler has shut down because it thinks the water inside is getting too hot too quickly, likely due to a circulation problem.
Your boiler has detected that the water pressure in the system is too low to operate safely and has shut down.
Your boiler has stopped working because the water pressure inside the system has dropped too low.
Your boiler has experienced a generic electronic system error that is preventing it from heating your home or water.
Your boiler has failed to light the flame or detect it after several attempts, so it has shut down for safety.
Your boiler has detected a flame lingering when it should have gone out, or a sensor incorrectly thinks a flame is present.
Your boiler has overheated, prompting a safety switch to shut the system down to prevent damage.
Your boiler has detected an issue with the fan that safely removes exhaust gases, meaning it has shut down for safety.
Your boiler has detected that the water pressure is too low or a sensor is unable to read the system pressure correctly.
Your boiler has detected that the water pressure is too low for the system to run safely and effectively.
Your boiler is struggling to monitor the water pressure correctly because the internal sensor is either failing or sending an incorrect signal.
Your boiler is receiving the wrong amount of electrical power from your home's supply, which has caused it to shut down for safety.
Your boiler has lost its ability to monitor the temperature of your hot water, which usually means it won't provide hot water to your taps.
Your boiler is having trouble controlling the size of its flame, meaning it cannot properly adjust the heat it produces.
Your boiler has detected a problem with the temperature sensor that controls your main heating circuit, meaning it cannot safely monitor how hot the water is getting.
Your boiler has detected that the water returning to the unit is getting too hot, suggesting a possible blockage or a sensor fault.
Your boiler has detected an unsafe level of carbon monoxide or poor combustion and has locked itself out for your safety.
Your boiler has detected a blockage or restriction in the flue pipe that prevents exhaust gases from safely leaving your home.
Your boiler has sensed that the exhaust gases are getting too hot and has shut down as a safety precaution to prevent damage.
Your boiler has detected a buildup of debris or sludge in its main heating component, which is preventing it from heating your water efficiently.
BoilerFaultCodes