What does the Vaillant F.75 fault code mean?

Your boiler has noticed that the water pressure doesn't jump up when the internal pump turns on, which usually means there is either not enough water in the system or the pressure sensor is struggling to read it correctly.

How much does it cost to fix Vaillant error code F.75?

Typical repair cost for the Vaillant F.75 fault is £120-£250 including labour.

Vaillant F.75 Fault Code: What It Means & How to Fix It

What the manual says

Manufacturer manual

No sudden change in pressure was detected on turning on the pump | Water pressure sensor or/and pump defective Too little water in appliance; check adjustable by-pass

From this model's manual

Verified against the Vaillant/Vaillant Ecotec Plus Pro 839592 00 2004 installation & service 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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Boiler cover options

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Related fault codes

F.22View →F.73View →

All 119 fault codes on the ecoTEC plus 612 VU GB 126/3-5

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

d.00 d.01 d.02 d.03 d.05 d.06 d.07 d.08 d.09 d.10 d.11 d.17 d.18 d.19 d.22 d.23 d.25 d.26 d.30 d.33 d.34 d.35 d.36 d.40 d.41 d.44 d.47 d.50 d.51 d.60 d.61 d.64 d.65 d.67 d.68 d.69 d.70 d.71 d.72 d.73 d.75 d.76 d.77 d.78 d.80 d.81 d.82 d.83 d.84 d.90 d.91 d.93 d.97 F.00 F.01 F.02 F.10 F.11 F.13 F.20 F.22 F.23 F.24 F.27 F.28 F.29 F.32 F.60 F.61 F.62 F.63 F.64 F.65 F.70 F.71 F.72 F.73 F.74 F.76 P.1 P.2 P.3 P.4 P.5 P.6 S.00 S.01 S.02 S.03 S.04 S.05 S.06 S.07 S.08 S.10 S.11 S.13 S.14 S.15 S.16 S.17 S.20 S.21 S.22 S.23 S.24 S.25 S.26 S.27 S.28 S.30 S.31 S.32 S.34 S.36 S.53 S.54 S.76

Your boiler has noticed that the water pressure doesn't jump up when the internal pump turns on, which usually means there is either not enough water in the system or the pressure sensor is struggling to read it correctly.

What the manual says

Engineer required

Avoid the next call-out bill

Related fault codes

All 119 fault codes on the ecoTEC plus 612 VU GB 126/3-5

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