BoilerFaultCodesYour boiler is operating normally and is currently firing the burner to provide heating or hot water; this is a status message, not an error.
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: burner on
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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