Low
S.031 on Vaillant ecoTEC Plus 836

Your boiler is currently in standby mode because it is not being 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

Heatingmodehasbeendeactivatedandthereisnodomestichotwaterdemand.

From this model's manual
Verified against the Vaillant Ecotec Plus installation & service manual, page 79.
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 settingsTurn up the heating temperature on your wall controllerCheck if any hot water taps are closed properly

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Related fault codes

S.030View →S.032View →

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