Low
S.30 on Vaillant ecoFIT Pure 830

Your boiler is working perfectly, but it is currently being told to stay off by your room thermostat or smart home control system.

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.

Shared across the ecoFIT Pure 830 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

Check your room thermostat or smart heating app to ensure the target temperature is set higher than the current room temperature.Replace the batteries in your room thermostat if they are low.Check that your heating schedule is set to 'On' and not currently in an 'Off' or 'Away' period.

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Related fault codes

S.31View →S.32View →

All 157 fault codes on the ecoFIT Pure 830

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

conConnectiond.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.76F.77F.78F.83F.84F.85F.86F.87F.88F.89F.91P.00P.01P.02P.06S.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.76S.88S.91S.96S.97S.98S.99S.108S.109

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