Low
S.0 on Vaillant ecoTEC Pro / ecoTEC Plus

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

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 heat demand

From this model's manual
Verified against the Vaillant Ecotec Combi installation & service manual, page 43.
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 heating programmer is switched to 'On' or 'Timed'Open a hot water tap to see if the boiler status changes to indicate a demand

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S.1View →S.2View →S.3View →

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