Updating to r134a
Documentation: BMW AC retrofit instructions - R12 to R134a retrofitting The first thing to do is to check if you have an R134a compatible compressor.Buy the BMW AC retrofit kit (part# 82 31 9 067 396) or all the components needed for the retrofit or repair.
The impact on the Aftermarket The first changes in the Aftermarket have appeared for FIAT applications.
R134 drawbacks: The only drawback of R134 is that the cooling efficiency is not as good as R12, but I am pretty sure that you will not notice it (except if you live in the Death Valley).
Molecule of R134a are smaller and there for more prone to leakage...
This means vehicles built before January 2017 designed to use R134a refrigerant systems will need a manufacturing upgrade of the vehicle A/C system for the R1234yf type refrigerant to comply with new EU regulations.
The update also brings with it a new type of compressor oil for workshops and suppliers to be aware of.