Low
D.043 on Vaillant ecoTEC Plus 832

Your boiler is displaying a status code related to its internal heating settings rather than a breakdown, meaning it is simply calculating the required water temperature based on your current configuration.

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

Heatcurve

From this model's manual
Verified against the Vaillant Ecotec Plus installation & service manual, page 74.
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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