F.74
Vaillant fault code
Vaillant F.74: water pressure sensor signal outside the correct range (too high)
Engineer only
Vaillant describes F.74 on ecoTEC plus boilers as: water pressure sensor signal outside the correct range (too high). Possible causes Vaillant lists, for an engineer to check: water pressure sensor line short-circuited to 5 V/24 V, or internal fault in the water pressure sensor.
What you can safely do
There is nothing you can safely do yourself with this one. Leave the boiler off and book an engineer.
Call a Gas Safe engineer if
- Book a Gas Safe registered engineer.
Find a Gas Safe engineer near you
Opens the official Gas Safe Register search.
Applies to: ecoTEC plus. Codes can differ between models, so check your manual.