Low
D.001 on Vaillant ecoTEC Pro / ecoTEC Plus System

This is a normal operational status message indicating that your boiler is circulating water to safely cool down after the heating has been running.

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

Pumpoverrun:Heating

From this model's manual
Verified against the Vaillant Ecotec Pro Ecotec Plus System installation & service manual, page 54.
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

No action is required as this is a normal part of the boiler's shutdown process.Wait a few minutes for the pump to stop running automatically.If the code persists for hours or the system is noisy, restart the boiler by switching it off and on at the fused spur.

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