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Green 'Running' light on Glow-worm Swift Flow 100

Your boiler is working normally and is currently heating up water for your taps or your radiators.

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.

Technical description

Indicates the appliance is running/operational (typically during hot water demand).

What causes this fault?

This is not a fault, but rather a positive status indicator showing that the boiler is actively burning gas to generate heat. It appears when you turn on a hot tap or when your thermostat signals that the house needs warming up. Once the demand for heat or hot water is met, this light will typically turn off as the boiler enters standby mode.

DIY fix possible

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

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