Low
S.31 on Vaillant ecoFIT Pure 418

Your boiler is currently in standby mode because it has not been asked to provide any heating or hot water, likely due to your thermostat settings or the current weather.

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 Vaillant/Vaillant Ecofit Pure 412 installation & service manual, page 33.
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 the heating is set to 'On' or 'Auto'Increase the target temperature on your room thermostat to see if the boiler initiates a firing sequenceVerify that the boiler's summer/winter mode setting is configured correctly for your current needs

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Related fault codes

S.30View →S.34View →

All 129 fault codes on the ecoFIT Pure 418

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

cond.00d.01d.02d.04d.05d.07d.08d.09d.10d.11d.13d.16d.17d.18d.20d.23d.24d.25d.27d.28d.31d.33d.34d.40d.41d.43d.45d.47d.50d.51d.58d.60d.61d.62d.64d.65d.66d.67d.68d.69d.71d.75d.77d.80d.81d.82d.83d.84d.85d.90d.93d.94D.094d.95d.96D.096F.00F.01F.10F.11F.13F.22F.23F.24F.25F.27F.28F.29F.32F.49F.61F.62F.63F.64F.65F.67F.68F.70F.71F.72F.73F.74F.75F.76F.77F.83F.85F.87F.88F.89P.00P.01P.02P.03P.06S.01S.02S.03S.04S.05S.06S.07S.08S.20S.21S.22S.23S.24S.25S.26S.27S.28S.30S.32S.34S.39S.42S.46S.53S.54S.88S.91S.96S.98S.99S.108S.109

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