Low
S.31 on Glow-worm Ultimate3 Combi

Your boiler is perfectly healthy and is simply waiting for a signal because your heating is currently turned off or set to summer mode.

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

Noheatingdemand:Summermode,eBUScontroller,waitingperiod

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 thermostat or programmer settings to ensure the heating is set to 'On' or 'Auto'Increase the target room temperature on your controller above the current room temperatureCheck if your boiler is set to 'Summer' mode and switch it to 'Winter' or 'Combined' mode if you require central heating

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Related fault codes

S.30View →S.32View →

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