Charging A/C - 1997 Dodge Caravan

Clutch died on thsi van and I installed a used compressor. System
needed to be charged and I took it to a local garage thinking I'd be
there awhile. 15 minutes later I went into the service bay to check on
the progress and I saw the mechanic with one of the small can's hooked
to the van, just finishing..... I don't think he used his A/C machine,
I think he just dumped 2 small cans into it. Since the system was
empty how did he get the compressor to kick in? Jump the pressure
switch? And will the r134 just flow in to the empty system. Thought
when you did a vaccum to test and all ok the vaccum will suck the 134a
in. Long winded, sorry, and thanks in advance

On Fri, 03 Jun 2005 06:50:07 GMT, wrote:

>Clutch died on thsi van and I installed a used compressor. System
>needed to be charged and I took it to a local garage thinking I'd be
>there awhile. 15 minutes later I went into the service bay to check on
>the progress and I saw the mechanic with one of the small can's hooked
>to the van, just finishing..... I don't think he used his A/C machine,
>I think he just dumped 2 small cans into it. Since the system was
>empty how did he get the compressor to kick in? Jump the pressure
>switch? And will the r134 just flow in to the empty system. Thought
>when you did a vaccum to test and all ok the vaccum will suck the 134a
>in. Long winded, sorry, and thanks in advance

The r134a will pressurize most systems enough to allow the compressor
to engage & suck-in the rest, BUT:

Since the system was opened to allow for the compressor replacement,
it should have been pumped down to a high vacuum to remove any air in
the system & held there for at least 30 minutes to allow any moisture
to 'boil-off'. Good idea to replace the receiver/dryer too. You did
make sure the appropriate amount of refrigerant oil was added with the
used compressor, right??

Sounds like you now need to get a competant shop to remove the
moisture & NCG (air) which is now in the system. Or tools & supplies
are readilly available to do this yourself.

It's easy to be seriously hurt working with A/C if you don't know what
is involved. Judging by your initial question, I'd suggest you leave
it to a pro for safety's sake.

Regards, Al.



Regards, Al.

"Al Haunts" > wrote in message
...
> On Fri, 03 Jun 2005 06:50:07 GMT, wrote:
>
>
> It's easy to be seriously hurt working with A/C if you don't know what
> is involved. Judging by your initial question, I'd suggest you leave
> it to a pro for safety's sake.
>

He DID, he "took it to a local garage"

My experience is that 90% of the service places out there that claim to do
A/C work do
crappy jobs like this. Hell, any garage that buys R134a in the small cans
instead of in a large
container that is sitting on a scale all the time, probably isn't doing
enough A/C work to be
considered a pro when it comes to A/C

A/C work is no more dangerous than pushing a car off a jackstand onto your
foot. In fact
it's probably safer - I think you would be hard pressed to find an example
of someone dying
as a result of improper service on A/C - but there's lots of people maimed
and killed because
of cars falling on them because they used a tire changing jack to hold the
car up while they
went crawling under it.

The tools for servicing A/C are no more expensive than paying someone to do
it, (except for a
refrigerant reclamation machine, and you should be able to go to any garage
that claims to do A/C
work and have them take your freon out of your car) and if you know what
your doing and go
slowly and carefully you will be sure to do a better job than every other
A/C shop in the city,
save the very top shops.

Ted

Ted, I also have a Caravan 1995 that has R134a in it. It has small
leaks in the system that would cost me a bundle to fix, so I have been
getting it charged yearly. Every summer I have to charge it myself.

Do you know of some instructions that would help me charge my own? Here
is a link I found on operating the manifold
http://www.robinair.com/opmans/118571.pdf

Mike

I read about some Kool-Stop or something that seals leaks after you put
it in.

What do you think about that stuff?

I think to fix my leaks you have to remove the dash.