I have an issue with my air conditioner on my 1989 GMC Suburban. Here
are the current facts:

Converted to R-134
Compressor replaced (2x)
Condenser replaced
Dryer replaced
Orifice tube replaced

The issue is that whenever I engage the AC, there is a lot moaning
noise through-out the system. This noise has been present ever since
I converted to R134 and replaced the components above. A mechanic
first mentioned that the new compressor might have been bad. So I
replaced it again (part was under warranty). After we flushed and
evacuated the system the sound was still present. All tests are
reporting good. Could this be caused by too much oil in the system?
When I replaced the compressor and dryer, I did fill the system with
the factory recommend 8oz (4 in dryer and 4 in compressor) of oil. I
did tell the mechanic this before he charged the system, so I don't
think he would have put more in there.

Thoughts?

Thanks,
Mike Thompson
1989 GMC Suburban 3/4 Ton

On Fri, 07 Sep 2007 08:37:27 -0700, mikeandmelthompson (AT) gmail (DOT) com
wrote:


A system pressure check is in order. If it is over pressured it will
moan. What are high and low side pressures running? Also, 8 oz is a
lot of oil to add the system unless everything is new and dry. When
you replaced parts did you use a 1993 on R134 compressor, expansion
valve and condensor? These are bigger on R134 system because to try to
make up for reduced efficency of R134 vs R12. BTW, I have a 89 4x4
burb that I bought new and there is no way I would ever convert it to
R134.
-----------------
TheSnoMan.com

Johnsons Freeze 12 is the way to go
http://www.freeze12.com/
1981 K-20
blows 38
even when it's 118 in the Las Vegas heat!
Purge the 134 and fill it with freeze 12
you will be happy

Dave
Las Vegas NV.
Home of the "DRY MUD"
It's called Sand

"SnoMan" <admin (AT) snoman (DOT) com> wrote

On Sun, 9 Sep 2007 05:59:22 -0700, "Dave" <Sorrynoreply (AT) imfo (DOT) org>
wrote:


Lucky you have very low humidity and it a lot easier to cool the air
there as humidity increases the work load a lot on refrigerant. Not
sure what you would gain with Freeze 12 in a R12 system since it is
ablend of 80% R134a and 20% R142b and R134 is set to be banned in 2012
or sooner.
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TheSnoMan.com