Low
S.30 on Glow-worm Energy

Your boiler is working correctly, but it has been told by your wall-mounted thermostat to stay off, so it is waiting for a signal to start 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

Room thermostat is blocking heating mode.

From this model's manual
Verified against the Glow Worm Energy installation & service manual, page 32.
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 programmer settings.Increase the target temperature on your room thermostat to be higher than the current room temperature.Ensure your smart heating app or wall controller is set to 'On' or 'Schedule' mode.

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