Your boiler is currently operating normally and is in the process of heating your radiators.
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 mode
What causes this fault?
This code appears because your boiler is functioning exactly as it should and is currently burning gas to provide central heating. It is a status indicator rather than a fault, showing that the system has successfully ignited and is actively warming up your radiators. You will see this message whenever the thermostat calls for heat and the internal components are operating correctly.
This status is most frequently seen during autumn and winter when the central heating is used daily to maintain a comfortable home temperature.
DIY fix possible
This fault may be fixable without an engineer. Check your manual first.
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A boiler cover plan would cover faults like S.24 — no call-out fees, no surprises.
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