BoilerFaultCodesYour boiler has shut down because it has become too hot and needs to be safely reset after cooling down.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: Overheat lockout
What causes this fault?
This fault occurs when the water inside the heat exchanger exceeds a safe temperature limit, triggering a safety cutout to prevent damage. The most common reasons include a failing circulation pump that isn't moving heat away quickly enough or a blockage in the system pipework. It can also be caused by a faulty internal sensor incorrectly reading the temperature.
This issue often surfaces during the first cold spell of autumn when the heating is turned on after being dormant all summer, which can cause internal pump components to seize.
DIY fix possible
Turn the boiler thermostat knob to the 'OFF' position.Wait at least 10 seconds for the system to acknowledge the reset.Turn the thermostat knob back to your desired temperature setting.
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