BoilerFaultCodesYour boiler has sensed that it is starting to overheat and has shut itself 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: Limit thermostat fault
What causes this fault?
This fault occurs when the temperature inside the boiler exceeds a safe limit, causing a safety sensor to trip and shut the system down. The most common reasons are a pump failure that prevents hot water from moving away from the burner, or a build-up of sludge and limescale that restricts flow through the heat exchanger.
This fault is frequently seen when the heating is first turned back on in autumn, as pump components can seize up after being idle during the summer months.
DIY fix possible
Turn the mode selector switch to the OFF/RESET position, wait a few seconds, then move it back to the 'Hot Water' or 'Heating' position.Check that your radiator valves are open and not blocked by furniture.Ensure there is enough pressure in the system by checking the gauge is between 1 and 1.5 bar.
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