Low
S.109 on Glow-worm Ultimate 3 25R

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 Ultimate 3 25r installation & service manual, page 33.
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 external heating controls or room thermostat to ensure they are calling for heatSwitch the boiler off at the fused spur or mains power switch for 60 secondsTurn the power back on to see if the boiler resets to a normal operating mode

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