High
N.032 on Vaillant ecoTEC Plus 836

Your boiler is struggling to detect the flow of water because of trapped air or a faulty sensor, meaning it cannot reliably heat your home or water.

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

Air in the system. The volume flow sensor is defective or the signal is not plausible.

From this model's manual
Verified against the Vaillant Ecotec Plus installation & service manual, page 93.
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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