BoilerFaultCodesWhat the manual says
Manufacturer manualburner on
From this model's manual
Verified against the Glow Worm Flexicom Cx installation & service manual, page 45.
What causes this fault?
This code appears when the boiler's internal controls have successfully confirmed that gas and air are present to ignite the burner. It signifies that the system is currently active and burning fuel to reach the temperature requested by your thermostat or hot water tap. This is part of the boiler's normal operating sequence rather than a mechanical failure.
DIY fix possible
Check your room thermostat or programmer if you did not expect the heating to be onEnsure your taps are fully closedNo action is required as this is a normal operational code
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