Low
S.0 on Vaillant ecoTEC 65kW

Your boiler is currently in standby mode because it has not received a request for heating or hot water from your thermostat or controls.

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:Noheatdemand

From this model's manual
Verified against the Vaillant/Vaillant Ecotec 65kw installation & service manual, page 34.
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 is set to a temperature higher than the current room temperatureEnsure your external timer or programmer is currently set to an 'ON' periodCheck if any smart heating app or control hub is set to away mode or standby

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Related fault codes

S.1View →S.2View →S.3View →

All 122 fault codes on the ecoTEC 65kW

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

D.0D.1D.2D.4D.5D.7D.8D.9D.10D.11D.12D.13D.14D.15D.17D.18D.20D.22D.23D.25D.26D.27D.28D.30D.33D.34D.40D.41D.44D.47D.50D.51D.60D.61D.64D.65D.67D.68D.69D.71D.72D.75D.76D.77D.78D.80D.81D.82D.83D.84D.90D.91D.93D.96D.97D.98F.0F.1F.10F.11F.13F.20F.22F.23F.24F.27F.28F.29F.32F.49F.61F.62F.63F.64F.65F.67F.70F.71F.72F.73F.74F.75F.77P.0P.1P.2P.5P.6S.1S.2S.3S.4S.5S.6S.7S.8S.20S.21S.22S.23S.24S.25S.26S.27S.28S.30S.31S.32S.34S.36S.39S.41S.42S.53S.54S.59S.85S.96S.97S.98S.O

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