BoilerFaultCodesYour boiler is operating normally and is currently heating up to provide warmth or hot water.
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 is actually a normal status message rather than a fault, appearing when the boiler has successfully ignited the burner to meet a demand for heating or hot water. It indicates that the internal components have completed their safety checks and the boiler is now actively burning gas to heat your home. You do not need to take any action, as this code simply confirms the system is working as intended.
You will see this code more frequently during the winter months when your heating is running regularly to keep your home warm.
DIY fix possible
No action is required as this is an status update rather than a fault.Check your thermostat settings if you did not expect the heating to be on.Monitor the display to see if it changes once the home reaches the desired temperature.
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A boiler cover plan would cover faults like S.04 — no call-out fees, no surprises.
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