BoilerFaultCodesYour boiler has become too hot and has automatically shut down for safety.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: The overheat sensor has operated. After the boiler has cooled, press the reset button. The boiler should now operate.
What causes this fault?
This fault occurs when the water inside the boiler reaches an unsafe temperature, triggering a safety switch to kill the flame. The most common reasons are a pump failure preventing heat from being moved away from the heat exchanger, or a blockage in the pipework restricting flow.
This issue often surfaces when the heating is first turned on in autumn, as internal pumps can seize up after being inactive throughout the summer.
DIY fix possible
Wait for the boiler to cool down completely (at least 20-30 minutes).Locate the reset button on the control panel.Press the reset button once; the flashing light should stop and the boiler should restart.
Find a Gas Safe engineer
Search the official register for a qualified engineer in your area.
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