Medium
D.146 on Vaillant ecoTEC plus System

Your boiler has detected that the ignition electrode, which helps light the flame, has reached the end of its intended service life and needs to be replaced.

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

Enablecontrolelectrodereplacement

From this model's manual
Verified against the Vaillant Ecotec Plus installation & service manual, page 77.
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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