[W126 Coupe] Air Conditioning Issues

[Richard Hogarth]

Ah yes, the R12 > 134 issue.
I live in lake Charles, Louisiana and I can only offer you some of my
experience with that changeover. Keep in mind that 98 degree days with 100 %
humidity are the norm here for 4 to 5 months of the year. 
I have a '91 560 sel that I converted to 134 several years ago and I am
completely pleased with the performance of the air conditioning; even with
our heat and humidity!

When doing the change over do a "complete" job. 
First make sure that the evaporator does not seep freon. Replace the
Compressor with a rebuilt one. Replace all of the seals. Replace the
expansion valve.
When the evaporator is open, squirt 2 cans of chlorinated Brakleen into the
condenser coil and cap off the open ends for 20 min or half an hour. Then
blow all of the junk and liquid out of the condenser coil with high pressure
air. Blow out the system from each end.  Make sure that all of the vent
doors seal properly. You should be plenty happy with the 134 system. 

And now the Volvo; I've owned and worked on plenty of them. 
My policy with Volvo air condition is the following:
Never leave the design of auto air conditioning to people who live above the
arctic circle. It's never going to work the way you want it to. 
-RPH