High
L.032 on Vaillant ecoTEC plus 940 VUI 30/40CS/1-5

Your boiler is struggling to accurately measure the speed of the water circulating inside it, which will prevent your heating and hot water from working correctly.

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

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

From this model's manual
Verified against the Vaillant/Vaillant Vaillantpro 0020308121 05 Ecotecplus Storage Combi Installation 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 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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Avoid the next call-out bill

A cover plan would handle faults like L.032: no call-out fees, no surprise bills.

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Related fault codes

All 125 fault codes on the ecoTEC plus 940 VUI 30/40CS/1-5

Seeing a different code? Every code this model can display, in one place.

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