Low
D.005 on Vaillant ecoTEC pro

Your boiler is simply displaying the current temperature setting for the water flowing through your heating system, rather than indicating a fault.

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 target flow temperature

Shared across the ecoTEC pro range
This code is shared by the boilers in this range, which use the same control board. It may not be printed in this exact variant’s manual.
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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All 157 fault codes on the ecoTEC pro

Seeing a different code? Every code this model can display, in one place.

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