BoilerFaultCodesYour boiler has shut itself down as a safety precaution because the water inside has become far too hot.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: Neon indicating boiler status: The preset overheat thermostat has tripped due to excessive temperature
What causes this fault?
This fault occurs when the internal temperature of the boiler exceeds safe limits, triggering a safety switch to prevent damage. It is usually caused by a failure to move hot water away from the heat exchanger, often due to a seized pump, a blockage in the pipework, or a faulty sensor misreading the temperature.
This issue often appears when the heating is first turned on after summer, as the circulation pump can seize up during long periods of inactivity.
DIY fix possible
Wait at least 15 to 30 minutes for the boiler to cool down completely.Ensure all radiator valves are fully open and there is no air trapped in the system.Locate the manual reset button on the control panel, press it firmly, and see if the boiler restarts.
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A boiler cover plan would cover faults like Overheat — 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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