Low
D.008 on Vaillant ecoTEC Pro 30

Your boiler is currently receiving a signal from your thermostat that it is asking for heat, which is normal operation rather than an error.

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

Room thermostat at terminal RT

From this model's manual
Verified against the Vaillant Ecotec Pro 30 installation & service manual, page 31.
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 settings to see if the heating is scheduled to be on.Adjust the thermostat temperature dial lower to see if the boiler stops firing.Consult your thermostat manual to ensure the device is communicating correctly with the boiler.

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