Low
S.31 on Glow-worm Ultimate 3 25R

Your boiler is currently in standby mode because it has not been asked to provide any heating or hot water, likely because it is set to summer mode or your room thermostat is turned down.

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

No heating demand: Summer mode, eBUS controller, waiting period

From this model's manual
Verified against the Glow Worm/Glow Worm Ultimate 3 25r installation & service manual, page 32.
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 room thermostat or smart controller and turn the temperature up to see if the boiler fires.Verify that your heating timer or programmer is set to 'On' for the current time period.If you only want hot water, ensure your summer mode settings are correctly configured on your control panel.

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Related fault codes

S.30View →S.32View →

All 161 fault codes on the Ultimate 3 25R

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

Connectiond.00d.01d.02d.04d.05d.06d.07d.08d.09d.10d.11d.13d.14d.15d.16d.17d.18d.19d.20d.21d.22d.23d.24d.25d.27d.28d.31d.33d.34d.35d.36d.39d.40d.41d.43d.45d.47d.50d.51d.58d.60d.61d.62d.64d.65d.66d.67d.68d.69d.70d.71d.73d.75d.77d.80d.81d.82d.83d.84d.85d.88d.90d.91d.93d.94d.95d.96F.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.77F.78F.83F.84F.85F.86F.87F.88F.89F22Neon 1 NOT litNeon 2 NOT litNeon 3 NOT litNeon 4 NOT litP.01P.02P.03P.04P.05P.06P.07S.0S.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.32S.33S.34S.39S.41S.42S.46S.53S.54S.88S.91S.96S.97S.98S.99S.108S.109

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