Low
S.109 on Glow-worm Ultimate3 System

Your boiler has entered a temporary sleep mode and is currently not heating your home or 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

Product's standby mode activated

From this model's manual
Verified against the Glow Worm Ultimate3 System installation & service manual, page 43.
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 thermostat or programmer to ensure it is set to demand heat or hot water.Ensure there are no active timer schedules preventing the boiler from firing.Restart the boiler using the reset or power button to see if it exits standby mode.

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