10 fault codes with plain-English explanations, severity ratings, DIY guidance, and repair cost estimates.
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Your boiler has detected an issue with one of its internal temperature sensors during its startup safety check and has safely locked itself out.
Your boiler has automatically shut down because the internal water temperature has become dangerously high.
Your boiler has detected that two of its internal temperature sensors have been wired up the wrong way around.
Your boiler has tried to start up, but it cannot detect a flame to keep it burning.
Your boiler is trying to start up, but it cannot reliably detect the flame needed to keep the burners running safely.
Your boiler is trying to light up, but it cannot safely detect the flame so it shuts itself off to keep your home safe.
Your boiler has detected that the internal fan responsible for safely pushing out exhaust gases is not spinning at the correct speed.
Your boiler has detected an issue with its internal temperature sensors or water flow detector, which usually means it needs a professional to test or replace the faulty part.
Your boiler has temporarily stopped working because it cannot properly read the temperature of the water inside the system.
Your boiler has detected an internal electrical problem with the safety component that controls the gas supply, meaning it has temporarily stopped working for your safety.
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BoilerFaultCodes