Low
S.01 on Glow-worm Energy Regular

Your boiler is currently performing a standard pre-heating safety check and will likely start up normally in a few moments.

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: Advance fan operation

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

Wait 5 minutes to see if the boiler automatically proceeds to ignitionIf the code persists, switch the boiler off at the fused spurWait 30 seconds and switch it back on to reset the system

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Related fault codes

S.00View →S.02View →

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.02S.03S.04S.05S.06S.07S.08S.20S.21S.22S.23S.24S.25S.26S.27S.28S.30S.31S.32S.34S.39S.42S.46S.53S.54S.88S.91S.96S.98S.99S.108S.109

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