BoilerFaultCodesYour boiler has become too hot and has temporarily locked itself to prevent damage until it cools down sufficiently.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: Overheat reset (displays 3 horizontal lines until temperature drops below 50oC)
What causes this fault?
This fault occurs when the water inside your boiler reaches a temperature that is dangerously high, triggering a safety shut-off to protect the internal components. It is most commonly caused by a pump failure that prevents water from moving around the system or a blockage that is restricting the flow of heat away from the boiler.
This fault is more frequent when you first turn the heating back on in autumn, as internal pumps can seize up after being inactive throughout the summer months.
DIY fix possible
Check that all radiator valves are fully open to allow water to circulate.Ensure your system pressure is between 1 and 1.5 bar on the pressure gauge.Wait for the temperature to drop below 50°C and then press the 'Reset' button.
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