F.64
Vaillant fault code
Vaillant F.64: electronics or temperature sensor fault
Engineer only
Vaillant describes F.64 on ecoTEC plus boilers as: electronics or temperature sensor fault. Possible causes Vaillant lists, for an engineer to check: flow or return sensor short circuited, electronics defective.
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.