freon

Nomen Nescio wrote:

>
> ...If in doubt, add R-12 until the outlet blows cold air. Its that simple...

And you don't know where you are in the tolerance band of "overcharged
and in danger of damaging the system" and "borderline undercharge and if
the temperature changes a little or the slightest bit leaks out, it may
not cool at all after next week".

Always use gages to properly charge it and run the most efficiently, not
risk damaging the system, and not having to do it again two weeks later
if you end up on the bleeding edge low side of charged.

>
> ...So
> what am I supposed to do sitting on dozens of cans when the law turned
> everything upside down? As it is, I've got enough to last about 50 years
> using my present car.

People here have reported seeing it on ebay all the time. There's your
answer. Turn that R12 into cash!

Bill Putney
(To reply by e-mail, replace the last letter of the alphabet in my
adddress with the letter 'x')

On Sun, 17 Jul 2005 10:10:09 +0200 (CEST), Nomen Nescio
> wrote:

>If in doubt, add R-12 until the outlet blows cold air. Its that simple.
>They say to look for bubbles in the sight glass then add so many more
>ounces, but that never works for me.

Unless of course the orifice is clogged in which case your advice will
get someone hurt when the high pressure builds enough to blow out a
hose. The only proper way to recharge the system is to use a manifold
gauge while monitoring both high and low pressures.

You are right in most cases but it isn't a good idea to tell someone
who doesn't really understand how it all works to just keep adding
refrigerant unitl you get cold air.

>shop manual you will see an expensive vacuum pump - you will never need
>that as long as there is some positive pressure in the system. Test that
>by using a small screwdriver to press on the Shraeder valve to release a
>little gas. If you hear gas escaping, there is positive pressure in the

also not true. a system that is empty at 70 degrees will give you a
hiss when hot.

>
>By the way, I have found all a/c systems to leak a little, if ever so
>slowly. Its not really a closed system like a home refrigerator which is
>all welded together. The compressor seal has to seep a little and the
>hoses must have some small porosity. Anyways, after a couple of years,
>they all need at least a 12 oz injection of R-12, if not more. This proves
>the fallacy of the law - all systems naturally leak and those leaks are
>many times over the amount of R-12 released than all of you out there put
>together serving your own cars with K-Mart R-12, willy-nilly.
>

Past the late 80's the systems don't seem to leak nearly as much. We
had several R12 cars of the era that never needed a drop of refrierant
added before they failed (we live in south fl so the a/c on cars
generally seems to fail a few times during the life of the car since
it is used every day of the year)

All my pre late 80's cars did leak a little as you described. A can
every other year seemed to keep them happy.

Steve B.