Medium
F.74 on Vaillant ecoTEC plus 937

Your boiler has detected that the internal water pressure reading is too high due to a sensor or electrical fault.

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

Signal water pressure sensor in the wrong range (too high) - Harness to water pressure sensor has a short-circuit at 5 V / 24 V or internal fault in water pressure sensor

From this model's manual
Verified against the Vaillant/Vaillant Ecotec Plus 937 Vui Gb 376 3 5 Isim 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 fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.

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Related fault codes

F.73View →F.75View →

All 38 fault codes on the ecoTEC plus 937

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

conF.0F.01F.02F.03F.10F.11F.12F.13F.20F.22F.23F.24F.25F.27F.28F.29F.32F.49F.61F.62F.63F.64F.65F.67F.70F.71F.72F.73F.75F.76F.77F.78F.80F.81F.90F.91

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