10 fault codes with plain-English explanations, severity ratings, DIY guidance, and repair cost estimates.
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Your boiler's internal temperature sensor has stopped communicating correctly, preventing the system from heating your radiators.
Your boiler has detected a problem safely discharging exhaust gases or removing waste water, causing it to shut down for safety.
Your boiler's hot water sensor has stopped working, so the system is unable to tell how hot your water is and has stopped heating it for safety.
Your boiler has reached an excessively high temperature and has shut down as a safety precaution to prevent damage.
Your boiler has lost water pressure and has stopped working to protect itself from damage.
Your boiler is struggling to move water around the system properly, which is causing it to shut down to prevent overheating.
Your boiler has shut down because a sensor has detected that the exhaust gases are getting too hot or the sensor itself has failed.
Your boiler is not receiving enough gas or is struggling to light the flame needed to heat your water and radiators.
Your boiler has detected a problem with the fan that helps clear exhaust fumes, meaning it has stopped working for safety reasons.
Your boiler has detected that water is not circulating correctly through the system before the burner ignites.
BoilerFaultCodes