Date: Sat, 11 Sep 1999 15:07:26 EDT
Reply-To: Gary McEachern <glmce@HOTMAIL.COM>
Sender: Vanagon Mailing List <vanagon@gerry.vanagon.com>
From: Gary McEachern <glmce@HOTMAIL.COM>
Subject: Re: AC pressure problem solved!
Content-Type: text/plain; format=flowed
My AC problem seems to be solved!
The problem I had been having with the fan wasn't that it was coming on when
the AC was turned on. I realize it should normally come on at the low speed
when the AC is first turned on. It will then kick the fan into second speed
(stage) if the pressure in the high pressure line gets too high. The problem
I was having was that the pressure was always too high and it was tripping
the high pressure switch and keeping it on for hours after I turned the AC
off. The fan would then run at mid speed for hours after I shut the AC and
van off. I had to remove power from the second stage relay to stop the fan
because once the fan is "on" with the high pressure switch "on", it latches
the second stage relay "on" at mid speed. The high side pressure was running
around 225-250 at this point with the low side around 50 with less than 2
lbs of R12 refgrigerant in the system.
This morning I assisted my mechanic friend in replacing the expansion valve
I received from Bus Depot last night.(Thank you Ron for getting it to me so
quickly.)
The low side pressure is now 30 lbs and the high side is 200 lbs @80C
ambient temperature with about 2.5 lbs of R12 in the system. The cooling and
the radiator fan appears to be operating properly at this point.
I'm keeping my fingers crossed that this is the end of my AC problems for a
while.
Gary
----Original Message Follows----
From: "David Snyder" <dsnyder@goodnet.com>
Reply-To: "David Snyder" <dsnyder@goodnet.com>
To: "Gary McEachern" <glmce@HOTMAIL.COM>, <vanagon@GERRY.VANAGON.COM>
Subject: Re: AC pressure question
Date: Sat, 11 Sep 1999 07:53:35 -0700
Gary,
Before you do anything, other than the fan running, is the system cooling?
Unless your VW is different from all Air Conditioned VW's I've owned, the
fan is supposed to come on whenever the compressor is running.
Assuming you are using R12 (Freon), your low side should be between 30 and
40 and your high side should be about 2.4XAmbient. (A little less than 2
1/2 times the outside temperature). On all my A1's '81, '82, '83, the
pressure of the high side has nothing to do with the fan operation. The fan
it turned on anytime the AC compressor is running. The high side pressure
switch just turns the AC Compressor off if the high side pressures get too
high (Over 300) I believe. It's possible that yours is different but I
doubt it. Activating the cooling fan when the high side pressure goes up is
like chasing the cows once they've left the barn.
Before you tear into the AC system, please check these and post and I'll let
you know what I think- Ambient Temperature, High Side Pressure, Low Side
Pressure, Duct Temp, R-12, R134a, or other refrigerant.
Dave
-----Original Message-----
From: Gary McEachern <glmce@HOTMAIL.COM>
To: vanagon@GERRY.VANAGON.COM <vanagon@GERRY.VANAGON.COM>
Date: Saturday, September 11, 1999 5:49 AM
Subject: AC pressure question
>Hello
>Does anyone have a good idea of what the normal/min/max pressures should
be
>like on the Air Conditioner's low and high pressure lines?
>
>My high pressure side is presently running around 225 and the high
pressure
>switch, that drives the stage 2 radiator fan, is constantly on as a
result.
>I'm having the expansion valve replaced today.
>
>Gary
>
>Gary McEachern, Reading Ma.
>'84GL,'87GL Wolfsburg
>'82L (4 sp, for sale)
>
>______________________________________________________
>Get Your Private, Free Email at http://www.hotmail.com
>
______________________________________________________
Get Your Private, Free Email at http://www.hotmail.com
