BoilerFaultCodesYour boiler is operating normally and is currently in the process of heating your water or 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 on
What causes this fault?
This is a status code rather than a fault, indicating that the boiler has successfully ignited the burner and is operating as intended. It appears when the system detects a demand for heat and is actively burning gas to warm up your home or hot water. If this code is showing, it means the internal components are working correctly and no repair is needed.
DIY fix possible
No action is required as this is a status message rather than a fault code.Wait for the boiler to finish its current heating cycle.Check your room thermostat if you feel the house is getting too warm.
Find a Gas Safe engineer
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Gas Safe Register →Protect yourself from future repair bills
A boiler cover plan would cover faults like S.04 — no call-out fees, no surprises.
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Glow-worm Flexicom cx is discontinued — time for a new one?
Parts for discontinued models can be hard to find and expensive. A new A-rated boiler could save you money on both repairs and energy bills.
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