BoilerFaultCodesYour boiler has become too hot and has shut itself down for safety purposes.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: OVERHEAT ERROR
What causes this fault?
This fault occurs when the water inside the boiler exceeds a safe temperature limit, triggering an emergency shutdown to prevent damage. It is usually caused by a lack of water flow, often due to a pump failure or a blockage within the pipework that prevents heat from being carried away from the unit. In some cases, a build-up of limescale or sludge acts as an insulator, causing the internal components to get too hot too quickly.
This fault is frequently seen at the start of autumn when heating systems are turned back on after a long summer break, as internal pump components may have seized from disuse.
DIY fix possible
Check that all radiator valves are fully open to allow water to circulate.Ensure your system water pressure is between 1 and 1.5 bar on the gauge.Allow the boiler to cool down and press the reset button on the control panel.
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