BoilerFaultCodesYour boiler is working fine but it is not receiving a signal from your thermostat or timer to turn the heating on.
This is a minor fault. Keep an eye on it and mention it at your next annual boiler service. Reset the boiler and see if it clears.
Technical description: No heating demand from low voltage controls
What causes this fault?
This code appears when the boiler is ready and waiting to provide heat, but it hasn't received an electrical signal from your external controls to start firing. This usually happens because the batteries in your thermostat have died or there is a communication issue between the wireless receiver and the boiler. In some cases, it may simply mean the programmed heating schedule is currently set to 'off'.
This is frequently seen during the first cold spell of autumn when homeowners try to turn their heating on for the first time after several months of inactivity.
DIY fix possible
Check that your room thermostat is turned up higher than the current room temperature.Ensure your programmer or heating timer is set to 'On' or 'Auto'.Replace the batteries in your wireless wall thermostat if the screen is blank or showing a low battery symbol.
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