Medium
D.012 on Vaillant ecoTEC Pro 30

Your boiler is signalling that the internal pump responsible for sending hot water to your separate hot water cylinder is currently not operating as expected.

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

Status of cylinder charge pump

From this model's manual
Verified against the Vaillant Ecotec Pro 30 installation & service manual, page 31.
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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