Low
S.30 on Glow-worm Energy Regular

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.

Shared across the Energy range
This code is shared by the boilers in this range, which use the same control board. It may not be printed in this exact variant’s manual.
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 room thermostat to ensure it is set to a temperature higher than the current room temperature.Verify the thermostat has fresh batteries if applicable.Check if the heating schedule on your programmer or smart app is currently set to 'on'.

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Related fault codes

S.31View →

All 78 fault codes on the Energy Regular

Seeing a different code? Every code this model can display, in one place.

Connectiond.02d.94F.00F.01F.10F.11F.13F.20F.23F.24F.25F.27F.28F.29F.32F.49F.61F.62F.63F.64F.65F.67F.68F.70F.71F.72F.77F.78F.83F.84F.85F.86F.87F.88F.91P.01P.02P.03P.04P.05P.06P.07P.10S.0S.01S.02S.03S.04S.05S.06S.07S.08S.20S.21S.22S.23S.24S.25S.26S.27S.28S.31S.32S.34S.39S.42S.46S.53S.54S.88S.91S.96S.98S.99S.108S.109

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