Date: Mon, 7 Dec 1998 18:51:42 -0600
Reply-To: Joshua Van Tol <jjvantol@USWEST.NET>
Sender: Vanagon Mailing List <vanagon@vanagon.com>
From: Joshua Van Tol <jjvantol@USWEST.NET>
Subject: Re: WTB A/C gauges and vacuum pump
In-Reply-To: <366bef5b.387.0@jps.net>
Content-Type: text/plain; charset="us-ascii"
>My system is brand new and totally open and vented at this point. I am
>not going
>to use Freon. I will use a propane/butane mixture which is totally legal and
>more effecient that R12 or R134A
>
Propane and butane, in any mixture, are not approved for automotive AC use,
and never will be. They may be approved for stationary refrigeration
equipment though.
Even if they were, they're quite dangerous, and R-134a is cheap, and
despite what the skeptics (who usually aren't ac mechanics say), works
quite well in a vanagon AC system. Those service professionals that have
experience with R-134a will tell you that there is a VERY slight
degradation in performance with R-134a, but it can be minimized by making
sure the condensor, fan, baffling, etc is all in good shape, and, in the
case of underengineered AC systems, upgrading the fan and/or the condensor.
Actually, when I did AC repairs, we usually found that because of the
thoroughness of the repairs we did when converting, the system usually
worked as well as or better than before. Certain cars that had large
condensors and good fans faired better, of course. Some older cars,
particularly those with aftermarket AC systems, didn't do too well until
the condensor capacity was increased.
If you don't beleive me that propane is dangerous as a refrigerant, try
this experiment. Fill a garbage bag most of the way with air, then add
propane to increase the volume by 20 % or so. Tie end shut. Attach to a
LONG rope or string. Drag through a camp fire. That's what'll happen when
you open the door on your van after the evaporator starts leaking.
P.S. I WON'T be responsible if you get hurt or killed trying my experiment.
>>Grace Audio Engineering wrote:
>>>
>>> I am looking for a used set of A/C gauges and a vacuum pump for doing my
>
>>> own A/C work on my car.
>>> Bobby
>>> Folsom CA
>>> 916 988-1551
>> Warning!
>>
>> Unless you are licenced, this is against the law. You must
>>have the proper recycling equipment, etc. , in order not to
>>polute the enviroment with freon. Don't take this lightly.
>>Auto shops all over are being busted for improper proccedures.
>>Of course this maybe the screwed up county I live in, hear in
>>PGH. PA (IMHO).
Unless I'm mistaken, only shops must have a recycling machine. You, as a do
it yourself mechanic don't need to have one, but you still can't vent
refrigerant. The solution? Take the car to the shop, and tell them that
you'll let them keep the refrigerant if they'll remove it for you. Most
shops will happily do this, since a fully charged vanagon system holds
about 3-4 pounds of R-12, which has a market value of at least $60 these
days. BTW, R-134a costs about $3/lb, and you can buy it anywhere, as
opposed to proprietary mixes which often cost more, must be recovered, but
can't be recycled. Also, with any refrigerant blend (i.e. a refrigerant
consisting of more than one component) if the system gets low, you cannot
simply top it off. You must recover the existing charge, and recharge from
and empty system. The reason for that is that the components of the mix
invariably have different molecular sizes, and thus leak preferentially,
thus throwing the ratio (and thus the properties) of the mix off.
Joshua Van Tol -- jjvantol@lear.csp.ee.memphis.edu
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