Medium
F.327 on Vaillant ecoTEC plus Combi

Your boiler has detected that it is set up to provide hot water to a storage tank that isn't currently connected, causing it to limit how much water flows through your heating system.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed

Book a service

This fault should be looked at by a Gas Safe engineer within the next week or two. It may get worse if left.

What the manual says

Manufacturer manual

The minimum heating volume flow is limited due to there being no domestic hot water circuit connected.

From this model's manual
Verified against the Vaillant Ecotec Plus installation & service manual, page 90.
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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