Low
S.30 on Vaillant ecoTEC 65kW

Your boiler is perfectly healthy, but it is currently waiting for 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

Roomthermostat(RT)isblockingheatingmode

From this model's manual
Verified against the Vaillant Ecotec 65kw installation & service manual, page 35.
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 switched on and calling for heat.Increase the temperature setting on your thermostat to see if the boiler fires up.Check if your thermostat batteries need replacing.

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