Low
S.31 on Glow-worm Sustain 12s

Your boiler is currently in standby mode because it has not been asked to provide any heating or hot water, likely due to your thermostat settings or the current season.

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

No heating demand: Summer mode, eBUS controller, waiting period

From this model's manual
Verified against the Glow Worm Sustain 12s 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 room thermostat or boiler programmer to ensure it is set to 'on' or 'heating' modeIncrease the target temperature on your controller to exceed the current room temperatureCheck if your heating system is currently in summer mode and switch it to winter mode if you require radiators

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Related fault codes

S.30View →S.32View →

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