High
D.012 on Vaillant ecoTEC Pro / ecoTEC Plus System

Your boiler is struggling to pump hot water into your hot water cylinder, which means your taps or shower may not get warm.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed

Call an engineer soon

Book a Gas Safe engineer within 24 to 48 hours. Your boiler may be unsafe or could break down completely if left.

What the manual says

Manufacturer manual

Cyl.chargingpump

From this model's manual
Verified against the Vaillant Ecotec Pro Ecotec Plus System installation & service manual, page 55.
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 is a high severity fault. Stop using the boiler and call a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.

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