Low
D.164 on Vaillant ecoTEC Plus 832

Your boiler is notifying the system that it has been set up with a specific type of exhaust pipe, which is a configuration setting rather than a broken part.

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

Flueinstallationwithsingle-flueconfig uration

From this model's manual
Verified against the Vaillant Ecotec Plus installation & service manual, page 77.
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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