Low
Green Light on Glow-worm Swiftflow 100

Your boiler is working normally and currently providing heating or hot water as requested.

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

‘RUNNING’

From this model's manual
Verified against the Glow Worm Swift Flow 100 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; the green light indicates that the boiler's internal controls have successfully received a signal to operate. It physically confirms that the burner is lit and the system is currently delivering heat to your radiators or hot water to your taps. If this light is on, the boiler is performing its job exactly as intended.

DIY fix possible

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

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