BoilerFaultCodesYour boiler has sensed it is getting too hot and has shut itself down as a safety precaution.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: Check water system for overheating. Reset by turning temperature control knob off and on.
What causes this fault?
This fault occurs when the water inside the heat exchanger reaches a dangerously high temperature, triggering a safety sensor to cut the power. The most common reasons are a failed pump that isn't moving the water away fast enough, or a blockage such as air or sludge trapped within the pipework.
This issue often appears when the heating is first turned on after summer, as pump components can seize up during long periods of inactivity.
DIY fix possible
Check that all radiator valves are open and not turned to zero.Ensure there are no blockages in the system and that the pump is running.Reset the boiler by turning the temperature control knob to 'Off' and then back to your desired setting.
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A boiler cover plan would cover faults like Reset LED is lit — no call-out fees, no surprises.
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Parts for discontinued models can be hard to find and expensive. A new A-rated boiler could save you money on both repairs and energy bills.
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