My mechanic tells me, FWIW, that R134a works nearly as well as did R12,
however, nearly as well doesn't quite cut it when the temps are nudging 115
when trying to keep a big ol' soda cracker box comfortable.

Second hand info, but info nonetheless.

Karl Wolz

|
|John, my air conditioning works fine, cool enough for our
|needs in 100+ weather.  It cools as well as the previous R12
|system did before it required a condensor replacement, which
|was better than it worked after the condensor replacement.
|The fellow who did the conversion told me that given the large
|size of the condensor and evaporators on these vans, the
|coolant (claimed to have a little less heat capacity)  For me,
|it is, as I said, not as cold as my sedans, but it is cool
|enough for comfort.  I would not describe it as cold enough to
|"freeze a halibut."    Hope this helps.  David