BoilerFaultCodesYour boiler has become too hot and has automatically shut 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: Indicates the overheat thermostat has operated. Fault will be rectified by allowing the boiler to cool and turning the selector switch to the reset position.
What causes this fault?
This fault occurs when the water inside the boiler exceeds a safe temperature, causing the system to shut down to prevent damage. The most common reasons are a pump failure that stops water from moving or a blockage in the heat exchanger that restricts flow. It can also be caused by a faulty internal sensor that is incorrectly reporting the temperature.
This fault is frequently seen when the heating is first turned on after summer, as the internal pump can often seize or stick during long periods of inactivity.
DIY fix possible
Wait at least 30 minutes for the boiler to cool down completely.Turn the main selector switch to the 'Reset' position and hold for 5 seconds.Turn the switch back to the 'On' position and check if the burner reignites.Ensure all radiator valves are open and the system pressure is between 1 and 1.5 bar.
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