BoilerFaultCodesYour boiler is getting too hot too quickly and is shutting itself down to prevent damage.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: Boiler operates with high boiler water temperature
What causes this fault?
This fault occurs when water cannot travel through the boiler fast enough to carry heat away, causing the internal temperature to spike dangerously high. The most common reasons are a failed circulation pump that isn't pushing the water or a significant blockage within the pipework or heat exchanger. In some cases, it may simply be that the internal sensors have become faulty and are providing inaccurate heat readings to the control board.
This fault often appears when the heating is first turned on after summer, as the internal pump can seize up during long periods of inactivity.
DIY fix possible
Check that your radiator valves are fully openEnsure the central heating pump is runningCheck if the system water pressure is between 1.0 and 1.5 bar
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