Low
S.109 on Glow-worm Energy System

Your boiler is currently in a temporary power-saving standby mode and is operating normally.

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

Product's standby mode activated

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 thermostat or programmer to ensure a heating or hot water demand is activeEnsure your boiler's internal clock or timer is set to the 'On' or 'Clock' positionWait a few moments for the boiler to wake up once a demand is detected

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Related fault codes

S.108View →

All 85 fault codes on the Energy System

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

ConnectionF.00F.01F.10F.11F.13F.20F.22F.23F.24F.25F.27F.28F.29F.32F.49F.61F.62F.63F.64F.65F.67F.68F.70F.71F.72F.73F.74F.75F.76F.77F.78F.83F.84F.85F.86F.87F.88F.89F.91F22S.01S.02S.03S.04S.05S.06S.07S.08S.10S.11S.13S.14S.15S.16S.17S.20S.21S.22S.23S.24S.25S.26S.27S.28S.30S.31S.32S.33S.34S.39S.41S.42S.46S.53S.54S.76S.88S.91S.96S.97S.98S.99S.108

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