Low
S.0 on Glow-worm Sustain 12s

Your boiler is currently in standby mode because it has not been asked to provide any heating or hot water at this time.

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

Heating mode: No requirement

From this model's manual
Verified against the Glow Worm Sustain 12s 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 room thermostat to ensure it is turned up higher than the current room temperatureEnsure your programmer or timer is set to an 'On' period for heating or hot waterCheck if any thermostatic radiator valves (TRVs) are set to their off position

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Related fault codes

S.1View →S.2View →S.3View →

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