Low
S.31 on Glow-worm Betacom4

Your boiler is currently idle because it is set to summer mode or your thermostat is not asking for 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 Betacom4 installation & service manual, page 35.
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 they are set to a temperature higher than the current room temperatureEnsure your heating programmer is switched to 'ON' or 'Timed' modeCheck if your boiler is set to 'Summer' mode and switch it to 'Winter' or 'Heating and Hot Water' mode if you require radiators

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