Medium
F.74 on Vaillant ecoFIT Pure 412

Your boiler's internal water pressure sensor is sending an invalid electrical signal, meaning the system cannot accurately read how much pressure is inside.

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

Water pressure sensor signal in the wrong range (too high)

From this model's manual
Verified against the Vaillant Ecofit Pure 412 installation & service manual, page 30.
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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