-Also, Air Conditioning repair

["Warren R Anderson" <wranderson@xxxx>]

>
>While I have the soapbox, I would also like to make everyone aware of a new
product marketed by NAPA for Air Conditioning leaks. It's from ETW and the
order number is CLP 940 kit. It works with both R-12 and R-134 and stops
leaks cold (pun intended). MY '95 LH New Yorker was subject to a recall
that the former owner did not avail himself of. As a result, the cost to
repair the non -functioning A/C in the car was over $800. I lived with no
A/C for years, tolerable in the Northeast and liking $800 more than a cool
breeze.


Chrysler LH cars have a leaky evaporator problem and dealers are supposed to
take care of the problem under warranty (some Mercedes has a similar probem;
tab for that one $3K+). Compressor O-rings also are a known leak source.
These seals are special and dealer only parts right now.

A/C stop leak will work with some types of leaks and from reports,
evaporator cores seems to be one of those applications. There are some
serious side effects that may or may not be mentioned in the literature. The
main problem that professional shops have noted is that the material will
turn to a gummy mess and plug up the system if moisture is present. The
refrigerant must be dry and free of non condensibles like air. What can
happen with a system that developes a leak is that the evaporator pressure
under a low system charge will pull down to less than atmospheric pressure
and moisture laden air will be introduced. If the system is not emptied and
evacuated to the proper level for an adequate time and then refilled with
dry refrigerant the system will be contaminated. There are other procedures
that have to be used in some cases to properly clear a system of non
condensibles.

Cars that we service are mostly from our dry southwest and moisture is not
the problem with this group that it is with cars from high humidity areas.

Stop leak will plug up refrigerant recycling machines. The initial cost of
these machines for a professional shop owner is in the thousands. The people
that manufacure these machines are reporting an alarming number of stop leak
plugged units being returned under warranty. I think if you check the RTI
site you should find a warranty disclaimer for such damage. If a
professional shop knows the stuff is in a system, he won't work on the
system. Working on a stop leak contaminated system is a big risk. Oh, by the
way, our expensive refrigerant identifiers that help us keep destructive
blended refrigerants out of our equipment will not detect stop leak
products.

Refrigerants do not get along with moisture. Some parts of R-134A do form
some really nasty items when they come into contact with moisture. R-12 is
easier to get along with in this regard.

Warren Anderson
Sedona,AZ (dry; real dry)