AC Stuff

[Al Powell <apowell@ezlink.com>]

Adam said:

Q: Just today I saw an R-134a retrofit kit for sale at a local parts
store.
The kit simply had a hose, two fittings, oil, and two cans of 134a, all
for $26.95. Since I own a formerly R-12 car (I say formerly because all
the freon is gone), I was interested. The kit makes no mention of the
reciever/drier or flushing and pulling a vacuum. This left me asking
"could it be this easy?"

A:  NO.  The lubricants, as noted, are totally incompatible.  You MUST
have the system vaccumed out completely by a shop before puting in new
refrigerant and lube.  Period.

Q:  I had always assumed that the reciever/dryer had to be replaced when

retrofitting. That seems to be the position of many mechanics.

A:  100% correct.  Once used with refrigerant A, it cannot be used with
B.  Replace it.  But go to NAPA for the part and you can get it for much
less than you quoted.

Other Q's:

1. Is it necesssary to replace the reciever/drier?  A:  YES.
2. What can happen if I don't?  A:  Unsure, but my money is on frying
the compressor because of mixing lubricants.  Why take a chance???????
3. Is it necessary to flush the system, and how can this be done.  A:
Vacuum it out, and have a shop do that procedure.  THEN replace all the
parts yourself, take it back to them, and have them add refrigerant and
lube.
4. How important is it to evacuate the system?  Q:  100%, absolutely,
completely mandatory.

Q:  I was figuring I could at leat blow out the system with a big can of

Dust-off (nitrogen).

A:  NO.  You MUST, I repeat, MUSY vacuum out the system to remove all
traces of lube.  However, once done, you are OK.  I hvae done a R134A
conversion with the procedure I outlined above.

Advice: I would not do this on a system designed for R12,  You lose at
least 30% cooling efficienty.  Pay the $$ and put R12 back in....IMHO.

Al Powell