Low
S.31 on Glow-worm Essential

Your boiler is currently in summer mode and is simply waiting for a signal from your thermostat to turn on the 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

Noheatingdemand:Summermode,eBUScontroller,waitingperiod

From this model's manual
Verified against the Glow Worm Essential installation & service manual, page 34.
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 settingsEnsure the heating mode is switched to 'ON' or 'Winter' modeIncrease the target temperature on your room thermostat to test for a response

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