Low
S.31 on Glow-worm MicraCom

Your boiler is currently set to summer mode, which intentionally prevents the central heating from turning on.

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

The summer mode is active dort he eBUS control is blocking the heating mode.

Shared across the MicraCom 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

Locate the display panel on the front of your boiler.Identify the settings or mode button on the interface.Change the setting from 'Summer' (often represented by a tap icon) to 'Winter' or 'Combined' (radiator and tap icon).

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Related fault codes

S.30View →S.32View →

All 138 fault codes on the MicraCom

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

d.00d.01d.02d.05d.06d.08d.09d.10d.11d.13d.14d.15d.16d.17d.18d.20d.21d.22d.23d.27d.28d.33d.34d.35d.36d.39d.40d.41d.43d.45d.47d.50d.51d.58d.60d.61d.64d.65d.67d.68d.69d.71d.80d.81d.82d.83d.85d.88d.90d.91d.93d.94d.96d.149d.165d.191d.192F.00F.01F.10F.11F.13F.20F.22F.23F.24F.25F.27F.28F.29F.32F.33F.46F.49F.61F.62F.63F.64F.65F.67F.68F.70F.71F.72F.73F.74F.75F.76F.77F.78F.83F.84F.85F.86F.87F.88F.89F.97S.00S.01S.02S.03S.04S.05S.06S.07S.08S.10S.11S.13S.14S.15S.16S.17S.20S.21S.23S.24S.25S.26S.27S.28S.30S.32S.34S.39S.41S.42S.46S.53S.54S.58S.76S.88S.91S.96S.98

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