Low
D.001 on Vaillant ecoTEC Pro 30

Your boiler is simply finishing its normal cooling process by moving leftover hot water through your radiators, which is a perfectly normal part of its operation.

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

Overrun time of internal heating pump for heating mode

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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Related fault codes

D.002View →D.003View →

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