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

Hot air from A/C after new compressor

chriskim_us on Mon August 09, 2010 7:03 PM User is offline

Year: 2002
Make: Chrysler
Model: Town & Country
Engine Size: 3.3
Refrigerant Type: R134A
Ambient Temp: 95
Pressure Low: 45
Pressure High: 190
Country of Origin: United States

Wish I had found this forum earlier, but hoping you guys might be able to help me.

A few weeks ago, my a/c compressor seized up causing the belt to smoke, so I recently had it flushed and replaced the compressor, drier and expansion valves. Pulled a vacuum which held for 1 hour.

The vehicle takes 48oz of R134A so I charged it with a refill kit initially, the air from the vents was about the same as just having the fan on and compressor was running constantly. We were suspicious that the cheap hose may have been leaking and had emptied all 4 cans of R134A into the system.

After this I bought a can tap for my manifold hoses and added another can with this, now the vents are blowing out hot air and after a while the compressor starts cycling and the low side pressure goes way up to about 120 and then back down to 45 but still hot air.

Do you think its still undercharged? Or should I start looking at something else?


UPDATE: I added about 6 oz of R134A to the system, the rear air is now cold, not ice cold but definitely cold. The front passenger side is blowing cold but less cold than the rear (I don't have a thermometer right now), and the front two driver side vents are a little warmer than ambient. I'm definitely confused now. Everything worked before the compressor seized so no reason for a blend door problem is there?

Edited: Mon August 09, 2010 at 7:25 PM by chriskim_us

EagleMark on Mon August 09, 2010 9:28 PM User is offlineView users profile

Untill you get an answer from the AC experts on here I would be very suspicious of the blend doors. Why would the rear be cooler than front?

1994 Buick Raodmaster Estate Wagon White Woodgrain. My four door Corvette Wagon! 1990 Chevy Suburban Silverado 5.7L 2wd and stuff! R12 Still Works!

Addicted and Obsessed with Fuel Injecting Anything!
[URL="http://"]Shared BIN files, Definitians and Wiring diagrams![/URL]

chriskim_us on Mon August 09, 2010 9:59 PM User is offline

Yeah that had me stumped too, however, I added another 12oz can of R134A to the system still suspecting low charge. That turned out to be the problem, the low side is still at 45 psi and the high side increased to 250 psi. Nice ice cold air now blowing out of all vents. Finally I can rest easy.

Thanks for your reply.

ice-n-tropics on Mon August 09, 2010 10:05 PM User is offline

Isentropic Efficiency=Ratio of Theoretical Compression Energy/Actual Energy. How To Air Condition Your Hot Rod

Edited: Mon August 09, 2010 at 10:09 PM by ice-n-tropics

ice-n-tropics on Mon August 09, 2010 10:07 PM User is offline

Recently I replaced the condenser in a 2001 Town & Country 3.3L. All the condensers eventually leak from the lower passenger corner. AC Kits had a exact replacement of the same design and thickness which performed as good or better than the OEM. I also had to add about 6 oz. extra of R-134a to get optimum cooling and superheat out of the evaporator.
The front evaporator can draw air from either the outside or recirculation mode but the rear evaporator is only recirculation which draws in cooler dehumidified air. When the front evaporator is in the outside air mode the louver air can be about 10 degrees hotter than in the recirculation mode.
Therefore be sure to set the front mode in recirculation by depressing the second button from the right each time the car is started.

Isentropic Efficiency=Ratio of Theoretical Compression Energy/Actual Energy. How To Air Condition Your Hot Rod

chriskim_us on Mon August 09, 2010 10:10 PM User is offline

Thanks for that information, that explains it. I was pretty sure it was something to do with recirculation because the problem went away when I hit the recirculate button. I didn't know about the back being only recirculate which explains why back was cold front was hot. With the extra R134a in there the front is now cold in both modes but colder in recirculation mode just like you said. I'm so relieved now, yesterday I had about given up and was planning to recover and rebuild the whole system meaning I wasted over $700. What a difference a day makes.

Thanks for your quick responses!

fasto on Tue August 10, 2010 3:37 PM User is offline

Did you replace the front evaporator? If not, it's going to leak out the refrigerant and oil again, and seize up your new compressor. Happened to me on a 1999 Plymouth Grand Voyager.

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.