14 fault codes with plain-English explanations, severity ratings, DIY guidance, and repair cost estimates.
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Your boiler has reached its programmed time limit for a scheduled service and is prompting you to book a professional engineer to check the system.
Your boiler has entered a temporary standby mode, which often happens if the system is waiting for the room thermostat to request heating or a hot tap to be opened.
Your boiler has failed to light the flame needed to produce heat or hot water, and it has locked itself out for safety.
Your boiler has detected that it is running too hot and has safely shut itself down to prevent damage.
Your boiler is struggling to detect that the internal fan, which clears exhaust gases, is spinning correctly.
Your boiler has stopped working because the water pressure inside the heating system has dropped too low.
Your boiler’s internal computer chip has lost the connection to its pre-set configuration settings, meaning it doesn't know how to operate correctly.
Your boiler has detected that the water temperature is too hot or the sensor measuring it is broken, so it has shut down to prevent damage.
Your boiler has detected that the water temperature returning to it is unusually high or that the sensors are not reading the temperature correctly, causing it to shut down to prevent damage.
Your boiler has detected that the exhaust gases are becoming dangerously hot, so it has shut down to prevent damage or safety risks.
Your boiler has detected a flame inside the unit when it was supposed to be turned off, so it has safely shut itself down to prevent a hazard.
Your boiler's internal computer is receiving an unexpected temperature reading from a sensor, which has caused it to stop working for safety reasons.
Your boiler has reached its programmed time limit and is simply reminding you that a routine safety service is now due.
Your boiler is currently recalibrating its internal settings to ensure it operates efficiently after a recent change or power cycle.
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BoilerFaultCodes