Low
S.31 on Glow-worm Energy 35 Store

Your boiler is currently in summer mode or simply waiting for your room thermostat to tell it that your home needs heat.

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

Summer mode active or no heat requirement from the eBUS controller.

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

Check your thermostat or programmer to ensure a heating or hot water schedule is currently active.Increase the target temperature on your thermostat above the current room temperature.Switch your boiler controls from summer mode (water only) to winter mode (heating and water) if you require radiators.

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Related fault codes

S.30View →S.33View →S.34View →

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

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