BoilerFaultCodesYour boiler is operating normally and is currently heating up to provide warmth for your radiators 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 not a fault, but a normal status message indicating that the boiler identifies a need for heat. It shows that the internal burner has successfully ignited and is now burning gas to heat the water for your central heating or hot water cylinder. You may see this code frequently during the winter months as the system works to keep your home at the desired temperature.
DIY fix possible
No action is required as this is an advisory status code rather than a fault.Check your thermostat or programmer to ensure the heating is scheduled to be on.Wait for the boiler to finish its heating cycle, at which point the code will change.
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A boiler cover plan would cover faults like S.04 — no call-out fees, no surprises.
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