Low
D.008 on Vaillant ecoTEC plus System

Your boiler is currently receiving a signal from your wall thermostat indicating that your heating should be turned off, so it is waiting for a command to start warming your home.

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

Turn up the temperature dial on your wall thermostat or heating controller.Check that your heating timer or programmer is set to 'On' and not a 'Standby' or 'Off' mode.Ensure your thermostat batteries are not flat if it is a wireless or digital unit.

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