BoilerFaultCodesYour boiler has become too hot and has shut itself down as a safety precaution 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: Overheat thermostat (requires reset)
What causes this fault?
This fault occurs when the internal water temperature exceeds a safe limit, causing the boiler to shut down to protect its components. The most common reasons are a lack of water flow caused by a failing pump, a blockage in the pipework, or a build-up of air within the heat exchanger.
This issue often surfaces when the heating is first turned on after summer, as the pump can seize or stick during long periods of inactivity.
DIY fix possible
Wait for the boiler to cool down completely (at least 20-30 minutes).Locate the reset button on the front control panel.Press and hold the reset button for a few seconds until the display clears.Ensure all radiator valves are open and the system pressure is between 1 and 1.5 bar.
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A boiler cover plan would cover faults like I — 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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