BoilerFaultCodes.com
Demand High

Your boiler is not currently receiving a signal from your timer or thermostat telling it to switch on.

Technical description: If not lit this indicates either timer or programmer is not calling for hot water / switch is not set to constant
Typical repair cost: £0-120 (including labour)

DIY fix possible

Check that your room thermostat is turned up higher than the current room temperature.Ensure your programmer or timer is set to 'ON' or 'AUTO'.Check if the batteries in your wireless thermostat need replacing.

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