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LED 2 Burner Lit on Glow-worm Micron 40FF

Your boiler is operating normally and the central burner is currently ignited and heating your water.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed

Monitor it

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.

What the manual says

Manufacturer manual

Burner Lit

From this model's manual
Verified against the Micron 80ff installation & service manual.
Plain-English guidance below. Severity, DIY steps, costs and parts are our interpretation to help you act, not text from the manual.

What causes this fault?

This is not a fault, but a status indicator showing that the gas valve has opened and the main burner has successfully ignited. It confirms that the internal components have completed their safety checks and the unit is now actively generating heat for your radiators or hot water. If the light is on, your boiler is functioning exactly as it should be.

DIY fix possible

This fault may be fixable without an engineer. Check your manual first.

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