BoilerFaultCodesYour boiler is not currently receiving a signal from your timer or thermostat telling it to switch on.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: If not lit this indicates either timer or programmer is not calling for hot water / switch is not set to constant
What causes this fault?
This occurs when there is a break in communication between your heating controls and the boiler. The most common reason is that your room thermostat or timer hasn't been set high enough to trigger a heat request, but it can also be caused by flat batteries in a wireless controller or a faulty receiver box failing to pass the signal through.
This issue is frequently noticed during the first cold spell of autumn when homeowners try to switch their heating on for the first time after the summer break.
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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