Low
S.30 on Glow-worm Essential

Your boiler is currently disabled because your room thermostat is telling it that the room is already warm enough.

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

Roomthermostatisblockingheatingmode.

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

Locate your room thermostat or smart controller.Turn the target temperature up higher than the current room temperature.Check if the boiler resumes heating after the thermostat clicks or lights up.

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