Low
S.31 on Glow-worm Energy Regular

Your boiler is currently in standby mode because your thermostat is not requesting any heating or hot water at the moment.

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

Shared across the Energy range
This code is shared by the boilers in this range, which use the same control board. It may not be printed in this exact variant’s manual.
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 settingsTurn up the target temperature on your thermostat to see if the boiler fires upEnsure your heating programmer is set to 'On' or 'Timed'

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Related fault codes

S.30View →S.32View →

All 78 fault codes on the Energy Regular

Seeing a different code? Every code this model can display, in one place.

Connectiond.02d.94F.00F.01F.10F.11F.13F.20F.23F.24F.25F.27F.28F.29F.32F.49F.61F.62F.63F.64F.65F.67F.68F.70F.71F.72F.77F.78F.83F.84F.85F.86F.87F.88F.91P.01P.02P.03P.04P.05P.06P.07P.10S.0S.01S.02S.03S.04S.05S.06S.07S.08S.20S.21S.22S.23S.24S.25S.26S.27S.28S.30S.32S.34S.39S.42S.46S.53S.54S.88S.91S.96S.98S.99S.108S.109

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