Low
S.109 on Glow-worm Ultimate3 Combi

Your boiler is currently in a temporary sleep mode and is simply waiting for a signal to start heating up again.

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

Product'sstandbymodeactivated

From this model's manual
Verified against the Glow Worm Ultimate3 Combi installation & service manual, page 45.
Plain-English guidance below. Severity, DIY steps, costs and parts are our interpretation to help you act, not text from the manual.

DIY fix possible

Check your room thermostat or smart controller settings to ensure a heating demand is active.Verify that your hot water taps are turned off and not dripping, which can confuse the system.Toggle the boiler power switch off and on again to perform a soft reset.

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