BoilerFaultCodesYour boiler has stopped working because it thinks it is overheating or a temperature sensor has malfunctioned.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: Flue/Case sensor fault - The sensor has detected an overheat or a sensor failure. This is a manual reset fault. To reset, press and hold the 'R' button for 2 seconds.
What causes this fault?
This fault occurs when the boiler's internal sensors detect that the exhaust gases or the main body of the unit are becoming too hot, which triggers a safety shutdown. The most common reasons are a build-up of debris inside the heat exchanger restricting air flow or a physical failure of the temperature sensor itself. In some cases, loose wiring connections between the sensors and the control board can also signal a false overheat reading.
DIY fix possible
Locate the 'R' button on the boiler control panel.Press and hold the 'R' button for at least 2 seconds to attempt a manual reset.Ensure that all radiator valves are open and there are no obstructions to the flue outside.
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