Low
S.0 on Vaillant ecoFIT Pure 435

Your boiler is currently in standby mode because it has not been asked to provide any heating or hot water at this moment.

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

Heating mode: No requirement

From this model's manual
Verified against the Vaillant/Vaillant Ecofit Pure 412 435 Open Vent 0020230535 installation & service 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 controller settings to ensure a temperature demand is setEnsure your heating timer or schedule is currently set to 'ON'Check that you have a demand for hot water by opening a tap

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Related fault codes

S.1View →S.2View →S.3View →

All 71 fault codes on the ecoFIT Pure 435

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

conF.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.84F.85F.87F.88F.89F.97S.01S.02S.03S.04S.05S.06S.07S.08S.20S.21S.22S.23S.24S.25S.26S.27S.28S.30S.31S.32S.34S.39S.42S.46S.53S.54S.88S.91S.96S.98S.99S.108S.109

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