Low
S.25 on Glow-worm Energy 35 Store

Your boiler is temporarily running the internal pump or fan to cool itself down after heating your home or water.

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/fan 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 process to finish, as this is a normal operating function.Ensure your radiator valves are open to allow heat to dissipate.If the code never disappears, try resetting the boiler once.

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Related fault codes

S.07View →S.08View →

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.26S.27S.28S.30S.31S.32S.34S.39S.40S.41S.53S.54S.96S.98S.99

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