Low
S.30 on Glow-worm 30cxi

Your boiler is currently idle because it is not receiving a signal from your thermostat or timer to turn the heating on.

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 from external controls 230V

From this model's manual
Verified against the Glow Worm Glow Worm 30cxi installation & service manual, page 52.
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 that your room thermostat or smart controller is set to a temperature higher than the current room temperature.Ensure your external timer or programmer is set to 'On' and that the schedule is active.Replace the batteries in your wireless thermostat if applicable, as low power can prevent the signal from reaching the boiler.

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Related fault codes

S.31View →S.33View →

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