Low
D.008 on Vaillant ecoTEC plus Combi

Your boiler is currently receiving a signal from your thermostat telling it to stay off, so it is waiting for a command to start 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

Roomthermostatstatus(230V)

From this model's manual
Verified against the Vaillant Ecotec Plus installation & service manual, page 73.
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 to ensure it is set to a temperature higher than the current room temperature.Verify that your thermostat is not in a 'holiday' or 'off' mode.Replace the batteries in your thermostat if it is a wireless unit.

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