Low
D.019 on Vaillant ecoTEC Pro 30

This code is not actually an error; it simply indicates that your boiler is currently running its water pump at a lower speed setting to save energy.

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

Operating mode of 2-stage pump

From this model's manual
Verified against the Vaillant Ecotec Pro 30 installation & service manual, page 32.
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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