Low
S.31 on Glow-worm Energy System

Your boiler is perfectly healthy and is currently in standby mode because it has not been asked to provide any heating.

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 Energy System 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 smart controller settings to ensure a heating temperature is requestedIncrease the target temperature on your controller to see if the boiler activatesVerify that the boiler is set to winter mode if you require central heating

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Related fault codes

S.30View →S.33View →

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