25 fault codes with plain-English explanations, severity ratings, DIY guidance, and repair cost estimates.
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Your boiler has stopped working because it cannot detect that water is flowing through the system, likely due to a loose wire or a faulty sensor connection.
Your boiler is confused because its outdoor weather sensor is sending a faulty signal, so it is running constantly to stay on the safe side.
Your boiler is struggling to detect the outdoor temperature, so it has defaulted to running constantly to ensure you stay warm.
Your boiler has stopped working because it is unable to accurately measure its own internal temperature due to an electrical connection issue.
Your boiler has stopped working because it has lost the electronic signal from the sensor that monitors the water temperature, causing it to shut down for safety.
Your boiler has stopped producing hot water because a sensor that measures water temperature is reporting a faulty electrical signal.
Your boiler has detected an electrical fault with the sensor that measures the flow of water, causing it to shut down for safety.
Your boiler has lost the signal from the sensor that monitors your hot water temperature, so it has temporarily stopped heating the water to prevent it from overheating.
Your boiler has lost its digital connection to your room thermostat or smart controller, so it cannot follow your temperature settings.
Your boiler has detected a sensor error related to its exhaust system and has stopped working to keep your home safe.
Your boiler has detected a faulty sensor reading in the flue system and has automatically shut down for your safety to prevent it from firing.
Your boiler has shut down for safety because it cannot correctly read the temperature of the exhaust fumes exiting your home.
Your boiler has detected an issue with a safety sensor and has locked itself out to prevent unsafe operation.
Your boiler has detected a safety issue and stopped working to prevent damage or dangerous conditions.
Your boiler has detected an internal error that has forced it to stop working for safety reasons and will not restart on its own.
Your boiler has detected an internal error that has forced it to safely shut down, meaning it is currently unable to provide heating or hot water.
Your boiler has automatically shut down because it detected that the exhaust gases leaving the system have become dangerously hot.
Your boiler has become too hot and has automatically turned itself off as a safety precaution to prevent damage.
Your boiler has detected a flame signal even though it is not currently trying to light, which means it has safely shut itself down to prevent a potentially dangerous situation.
Your boiler is failing to light because it cannot detect a flame, which means your heating and hot water have stopped working.
Your boiler has detected a safety concern where the internal gas supply did not shut off as quickly as it should have, so it has locked itself out to prevent any risk.
Your boiler's air circulation system has stopped working, meaning the unit cannot safely ignite to provide you with heating or hot water.
Your boiler has detected that the internal fan is not shutting down correctly, which prevents it from safely starting the next heating cycle.
Your boiler has detected an internal electrical communication error between its main brain and the fan that exhausts combustion gases, causing it to stop operating for safety.
Your boiler has detected an internal error that is preventing it from starting the burner and safely providing you with heating or hot water.
BoilerFaultCodes