Automotive Air Conditioning Information Forum (Archives)

Provided by

We've updated our forums!
Click here to visit the new forum

Archive Home

Search Auto AC Forum Archives

Vacumn check question

Scout3 on Sun September 28, 2008 8:08 PM User is offline

Year: 1994
Make: Plymouth
Model: Voyager
Engine Size: 3.0
Refrigerant Type: 134
Country of Origin: United States

I performed a vacuum check on my system after changing compressor and drier. My book says to pull vacuum, close gauges, turn off pump and monitor gauges for 5 minutes. If you lose less than 2 inches of vacuum in five minutes you are within specs. My system was within the 2 inches but I went and waited about 30 minutes and it lost about 5 inches total. To me, that means I have a leak that should be corrected. What say the experts? I didn't want to charge the system until I am sure.



Scout3 on Sun September 28, 2008 8:24 PM User is offline

I just read some more and if I read it right it is possible for you to lose some vacuum during the leak test as moisture boils out of the system. If this is correct, how many times, or how long to pull vacuum before checking for a leak? That for all the help you guys provide.


Chick on Sun September 28, 2008 9:33 PM User is offlineView users profile

Pull your vacuum a few times until it holds, the book is correct as moisture boils off, also refrigerant in the trapped in the oil, you will loose vacuum, run the pump a little longer too, you want to bring the microns down as low as you can (if you have a micron gauge, use it) But pull your vacuum two to three times, and it should hold.. Hope this helps..

Email: Chick


Freedoms just another word for nothing left to lose

Scout3 on Tue September 30, 2008 9:41 PM User is offline

Had a chance to get back to my ac repair. Replaced compressor and drier. Pulled vacuum again and it held steady this time. Maybe last time I had a loose fitting? Put in three 12oz cans. Low side 20psi High 210 at about 1800rpm. Outside air 86 degrees. Inside 46 degrees. I'm happy. Thanks for all the help.


Back to Automotive Air Conditioning Forum

We've updated our forums!
Click here to visit the new forum

Archive Home

Copyright © 2016 Arizona Mobile Air Inc.