RE: A/C changeover to R-134 in a 92 525iT

["Fadeev, Alex" <alex.fadeev@xxxxxxxxxxx>]

James H. BOYD III [mailto:byoda@domain.elided] wrote:
> 
> My a/c is low on R-12 and I assume there is leak somewhere. There
> are bubbles in the sight-glass.  I figured, if indeed I do have 
> to replace the compressor, I thought I might as well install an 
> R-134 compatible compressor and a new dryer to match so that I 
> could service it. 

James,
I do not believe you will need a new compressor to upgrade to R134a:
http://www.koalamotorsport.com/tech/ac.htm
In general, if you loose your R12 charge it is frequently cheaper to convert
to R134a than it is to fix the R12 system and charge it back up.

> How does the R134 perform compared to the R12? I am in fort 
> worth, so it gets pretty hot and humid.

I am in north Dallas with a R134a converted daily driver E30. It cool very
well. I never need to set the air flow at anything higher than 1 as long as
ambient temps remain below 100F. Below 90F I have to limit cooling by moving
the temp dial to about 9 o'clock or my finger start freezing on the steering
wheel. Comparing two not tinted cars, my R134a retrofitted E30 is cooling
better than my wife's E36.
There are some anecdotal reports that R134a will not cool as well as R12. In
my experience, that's not true.

> Does anyone know anything else I might need to replace in the 
> conversion?

Leave the compressor alone unless it's dead.
You will need new R134a friendly compressor oil, new dryer, new low/hi
pressure switches. The E30 retrofit kit is $250 from the dealer and $100
from the aftermarket sources. Not sure about E34 pricing.

> I know I will need to replace the oil with R134 compatible oil.

yep.

alex f

------------------------------