Date: Sun, 25 May 2003 21:36:09 -0400
Reply-To: lauterba <lauterba@BELLSOUTH.NET>
Sender: Vanagon Mailing List <vanagon@gerry.vanagon.com>
From: lauterba <lauterba@BELLSOUTH.NET>
Subject: Re: How long to pump down A/C ?
Content-Type: text/plain; charset="iso-8859-1"
Fred, thank you for your reply. Long pumping time does not suck the hoses
flat. Pulling the vacuum through the Schrader valve limits the pumping
speed even with the biggest vacuum pump. The objective in pumping down the
system is not only to remove the air, but also remove the water on the
surface of the tubing, etc. I know from many years experience with vacuum
equipment in the R&D lab that it generally takes pumping down overnight to
get rid of the water.
John
----- Original Message -----
From: "Fredrich Hesterberg" <FredsVW@WEBTV.NET>
To: <vanagon@GERRY.VANAGON.COM>
Sent: Sunday, May 25, 2003 2:56 PM
Subject: Re: How long to pump down A/C ?
16 hours?
Are you wanting to suck the hoses flat too?
Not needed this long to evacuate.
The most should take with worn out old pump, maybe 1 hour.
New O-rings are needed anytime system is opened at fittings.
Just a better job, no leaks.
Good Afternoon,
E-mail message
Steve, thank you for your reply. I reused the old O-rings as they were
tight. I put it in my question just in case reuse of the O-rings was a
non-no.
Right now, I have had the system pumping down for about 16 hours so it
should be dry by the time I fill it later this afternoon.
John
----- Original Message -----
From: "Steve Cotsford" <Cotsford@AOL.COM>
To: <vanagon@GERRY.VANAGON.COM>
Sent: Sunday, May 25, 2003 9:42 AM
Subject: Re: How long to pump down A/C ?
Why would you use the old o-rings ?
You can get adaptor kits at Pep Boys quite cheap and the new ones are
bluish-green and work with all the oils you may encounter these days
whereas the old
black ones wont.
I would suggest that you pull the vacuum down for at least 45 mins.
Longer if you can wait.
If you are using a conventional gauge set , then you can open both high
and low side to the center hose, assuming thats where you have the pump
attached. Both sides will show a vacuum reading and I would like to see
at least 28. What kind of pump are you using? Sounds like a medical
pump. It maybe worth your while to borrow an automotive a/c pump
which probably wont give any volume values. Once a good vacuum is
pulled, I doubt if the volume means much.
I borrow a friends'. I dont know what brand it is, he just calls it
Monica,
lol
I have worked on 3 systems this spring, including converting my recently
sold
'84 Westy to R134a. If you want to chat on the phone about
it, I
would
be happy to.
p-mail me for the number.
good luck,
Steve Cotsford
Columbia SC
Fred
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