Low
S.27 on Glow-worm Energy 35 Store

Your boiler is temporarily running the pump after the heat has turned off to safely cool down the internal components.

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

Pump overrun.

From this model's manual
Verified against the Glow Worm/Glow Worm Energy 35 Store Installation And Maintenance Instruc installation & service 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 for the code to disappear naturally as the boiler cools downEnsure at least one radiator with a manual valve is fully open to allow water flowCheck that the system water pressure is between 1.0 and 1.5 bar

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Related fault codes

S.07View →S.28View →

All 72 fault codes on the Energy 35 Store

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

F.00F.01F.02F.03F.10F.11F.12F.13F.20F.22F.23F.24F.26F.27F.28F.29F.32F.42F.49F.52F.53F.54F.56F.57F.61F.62F.63F.64F.65F.67F.68F.70F.71F.72F.73F.74F.77F.79F.81F.83F.84F.85F.86F22S.08S.10S.11S.13S.14S.15S.16S.17S.20S.21S.23S.24S.25S.26S.28S.30S.31S.32S.34S.39S.40S.41S.53S.54S.96S.98S.99

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