a/c won't "pull" charge in, no leaks, good compressor

[Kim Johnson]

Chris,

If you bump up the idle to 1200 or 1300 RPM it will suck it up. NEVER,
NEVER, NEVER charge thru the high side because you run the risk of turning
that can of freon into a handgrenade. If you are unlucky it's "lights out"
if you know what I mean.

Kim Johnson
tq and 20V
others of lesser stature


----- Original Message -----
From: "Chris Covington" <malth at umich.edu>
To: <quattro at audifans.com>
Cc: <200q20v at audifans.com>
Sent: Friday, September 07, 2001 0:14
Subject: a/c won't "pull" charge in, no leaks, good compressor


> Today my friend and I replaced my compressor which appeared shot (you
> could turn it by hand and no pressure would come out, what a pain that is
> on a 20v BTW) with a known good one, and misc. o-rings, etc.
> The system has no leaks.  I don't know what the device is called that
> we're using to charge the system but it's fairly simple: 2 pressure
> gauges, one for the high (goes to 400 psi) and one for the low (goes to
> around 100psi), 2 connections to the high and low, and one connection to
> the tank of R12.  The line to the low has a small canister which you put
> the oil in, which gets sucked in with the pressure when everything is
> working fine.
>
> However, when we were attempting to charge it, we couldn't get the
> compressor to suck in the charge (not even the oil) even though the clutch
> is engaging via the low pressure switch being shorted to get it to pull
> in the R12.  We tried charging it through the low-pressure switch
> connection and the one right near the compressor to no avail.  The
> pressure on the high side and the low side stays at the same pressure as
> the tank of R12 (approximately 62 psi, the compressor sometimes would go
> to 75psi) so it seems like it isn't being compressed into the system.
> There are no leaks; the system held a charge before with the shot
> compressor and holds the 62 or so psi right now (nowhere near enough).
>
> What can prevent the charge from being pulled in, besides the compressor
> itself (which seems fine)?
>
> Chris
> '91 200q20v
>
>