20 fault codes with plain-English explanations, severity ratings, DIY guidance, and repair cost estimates.
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Your boiler is attempting to start but cannot get the flame to stay lit, so it has shut down as a safety precaution.
Your boiler has detected a flame signal even though it is supposed to be turned off, which prevents it from firing safely.
Your boiler has detected that it is running too hot and has automatically shut itself down to prevent damage.
Your boiler has detected an issue with the system that removes waste gases, so it has safely shut down to prevent the buildup of dangerous fumes.
Your boiler is trying to start but cannot detect a flame, so it has safely shut itself down to prevent gas from building up.
Your boiler has lost its electrical connection to the internal gas control system, meaning it cannot safely ignite to provide heating or hot water.
Your boiler has detected that the exhaust gases leaving the system are getting too hot, so it has shut down to prevent potential damage or overheating.
Your boiler is struggling to detect the flow of water because of a faulty electronic sensor, which will prevent your heating and hot water from working.
Your boiler is struggling to detect the flow of water through the system, which means it has stopped working to prevent potential damage.
Your boiler is struggling to detect the temperature of the water for your taps, which means it has stopped heating your hot water to keep the system safe.
Your boiler is having trouble measuring the temperature of the water flowing through it due to a faulty sensor, which means it has safely shut down to prevent overheating.
Your boiler has detected that the internal mechanism responsible for venting exhaust gases is not working correctly, so it has shut down for your safety.
Your boiler is temporarily shutting down because it is not receiving enough electricity from your home's power supply.
Your boiler is struggling to detect a consistent flow of electricity from your home's power supply, preventing it from starting up safely.
Your boiler has stopped working because the water pressure inside the system is too low.
Your boiler is struggling to read the outdoor temperature, so it is defaulting to a factory setting to keep your home warm.
Your boiler has stopped working because it is unable to accurately measure the temperature of the water used for your heating.
Your boiler has lost communication with one of its internal control modules, meaning it cannot operate safely and has shut down.
Your boiler has lost communication with one of its internal control modules, causing it to shut down for safety.
Your boiler is currently running a brief automatic process to clear trapped air from the system, and it will return to normal operation in two minutes.
BoilerFaultCodes