Low
d.19 on Vaillant ecoTEC Plus 625

This code is simply an information status display showing how your boiler's internal water pump is currently being told to operate, rather than an error or a fault with your heating system.

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

Pump operating mode, 2 stage pump: 0=Burner mode stage 2, pump flow/overrun stage 1; 1=Heating mode and pump flow/overrun stage 1, hot water handling mode stage 2; 2=Automatic heating mode, pump flow/overrun stage 1, hot water handling mode stage 2; 3=Stage 2

From this model's manual
Verified against the Vaillant Ecotec Plus 615 installation & service manual.
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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d.14View →d.18View →

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