Low
S.030 on Vaillant ecoTEC Plus 836

Your boiler is currently in standby mode because it is not receiving a signal from your thermostat to turn on the heating.

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

Nodemandispresentforthethermostat.Heatingmodeisblocked.

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 that your wall thermostat or heating programmer is switched on and calling for heat.Ensure the batteries in your wireless thermostat are fresh.Increase the temperature setting on your thermostat to see if the boiler responds.

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Related fault codes

S.031View →S.032View →

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