BoilerFaultCodes.com
FLASH OFF ON High

Your boiler has shut down because it has become too hot and needs to be safely reset after cooling down.

Technical description: Overheat lockout
Typical repair cost: £100-280 (including labour)

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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