Low
S.30 on Glow-worm Ultimate 3 25R

Your boiler is perfectly healthy, but it is currently being told to stay off by your wall-mounted thermostat or heating controller.

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

Room thermostat is blocking heating mode.

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 wall thermostat or heating programmer to ensure it is set to 'On' and the target temperature is higher than the current room temperature.Replace the batteries in your wireless room thermostat if it has a low battery indicator.Ensure your smart heating app (if applicable) is not currently overriding your heating schedule to 'Off'.

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Related fault codes

S.31View →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.31S.32S.33S.34S.39S.41S.42S.46S.53S.54S.88S.91S.96S.97S.98S.99S.108S.109

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