BoilerFaultCodesYour boiler is currently operating normally and the burner has successfully lit to provide heat 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 ignited
What causes this fault?
This is not actually a fault, but a status message indicating that the boiler’s internal sequence is progressing correctly. It appears when the gas gas has successfully ignited and the burner is currently producing heat for your radiators or hot water. If your boiler seems stuck on this code without producing heat, it may be waiting for a signal from the thermostat or internal sensors.
DIY fix possible
No action is required as this is a status code, not an error.Monitor the boiler to ensure it transitions to other 'S' codes as demand changes.If the code persists without heating being delivered, check that your thermostat is turned up.
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A boiler cover plan would cover faults like S.4 — no call-out fees, no surprises.
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