Medium
F.74 on Vaillant ecoTEC plus 612 VU GB 126/5-5

Your boiler has detected an electrical reading from the water pressure sensor that is too high, meaning it cannot safely monitor the system pressure.

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 outside correct range (too high) Cable to water pressure sensor has short-circuited at 5 V/24 V or internal fault in water pressure sensor

From this model's manual
Verified against the Vaillant/Vaillant Ecotec Plus 612 4104460 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 121 fault codes on the ecoTEC plus 612 VU GB 126/5-5

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

Communication faultD.000D.001D.002D.003D.004D.005D.006D.007D.008D.009D.010D.011D.012D.013D.014D.015D.016D.017D.018D.019D.020D.022D.023D.025D.026D.027D.028D.033D.034D.035D.036D.039D.040D.041D.044D.046D.047D.050D.051D.058D.060D.061D.064D.065D.067D.068D.069D.070D.071D.072D.073D.075D.076D.077D.078D.080D.081D.082D.083D.084D.088D.090D.091D.093D.094D.095D.096D.098F.00F.01F.02F.03F.10F.11F.12F.13F.20F.22F.23F.24F.25F.26F.27F.28F.29F.32F.35F.42F.49F.52F.53F.54F.56F.57F.61F.62F.63F.64F.65F.67F.68F.70F.71F.72F.73F.75F.76F.77F.78F.83F.84F.85F.91F.92F.93S.11S.16S.17S.24

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