Low
S.30 on Glow-worm Ultimate3 Combi

Your boiler is currently prevented from heating your home because your room thermostat is telling it to stay off.

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

Roomthermostatisblockingheatingmode.

From this model's manual
Verified against the Glow Worm/Glow Worm Ultimate3 Combi installation & service manual, page 45.
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 settings to ensure it is set to 'On' or 'Heat'.Increase the target temperature on your room thermostat to be higher than the current room temperature.Replace the batteries in your wireless room thermostat if the display is blank or shows a low battery icon.

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Related fault codes

S.31View →S.32View →

All 170 fault codes on the Ultimate3 Combi

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

d.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.89F.97F2F22Main burner does not lightNeon 1 lit (No)neon 1 not litNeon 2 lit (No)neon 2 not litNeon 3 lit (No)neon 3 not litNeon 4 lit (No)neon 4 not litP.01P.02P.03P.04P.05P.06P.07Pilot does not lightPilot does not stay alightPump OverrunS.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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