Low
S.30 on Glow-worm Energy System

Your boiler is perfectly healthy, but it is currently waiting for a signal from your wall-mounted thermostat to tell it 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

Room thermostat is blocking heating mode.

From this model's manual
Verified against the Glow Worm Energy System installation & service manual, page 33.
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 wall thermostat or heating controller is set to a temperature higher than the current room temperature.Ensure your thermostat is not in 'off' or 'frost protection' mode.Replace the batteries in your wireless thermostat if applicable.

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Related fault codes

S.31View →S.33View →

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