Low
D.000 on Vaillant ecoTEC Pro / ecoTEC Plus Regular

This code is simply a status message showing the boiler is currently operating at a reduced capacity, not a fault requiring any action.

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

Heating partial load

From this model's manual
Verified against the Vaillant Ecotec Pro Ecotec Plus Regular 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.

Engineer required

This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.

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