Old Jeep AC Help

CDS1042 on Mon June 22, 2015 12:30 PM

Year: 87
Make: Jeep
Model: Wrangler
Engine Size: 4.2l
Refrigerant Type: 134a
Ambient Temp: 90
Pressure Low: 19
Pressure High: 225
Country of Origin: United States

This is one of the add on systems they offered on this model Jeep. A few years ago I switched it over to 134a and the vent temp stays around 60 deg. My question is this normal for this system, should I be getting a little cooler temps out of the vent or am I asking too much out this system.

Also when I start up the low is 35 then slowly drops to 19. I am guessing most of the system is original with the exception of the receiver drier which was changed during the switch.

Thanks in advance.......

mk378 on Mon June 22, 2015 2:25 PM

Try a little more refrigerant. If the condenser is tube and fin, you may be undercharging it trying to keep the high side down.

How does it do while driving vs. at idle?

Edited: Mon June 22, 2015 at 2:27 PM by mk378

CDS1042 on Mon June 22, 2015 2:35 PM

While driving and at idle it maintains the temp. It does not go down and might improve just a little as I drive...Could this possibly be a moisture problem?

Dougflas on Mon June 22, 2015 9:34 PM

mist the condenser with a water hos IF high side drops like a rock you have airflow across condenser problem.

CDS1042 on Wed June 24, 2015 9:33 AM

I mist the condenser and it did drop from 225 to under 150 on the high side. The low side also dropped to under 10. I have recently replaced the fan clutch, radiator, cooling system seems to function fine. Any ideas? I appreciate all help......

mk378 on Wed June 24, 2015 3:30 PM

Tube and fin condenser then? That type of condenser has copper tubes with U bends at each end, pushed through aluminum fins. They don't work very well with R-134a, because it is harder to condense than R-12. You could replace the condenser with a parallel flow type for better performance.

Though I still think if you put a little more refrigerant in it could work better, at least on the highway where you get lots of airflow.

CDS1042 on Wed June 24, 2015 8:28 PM

It does have the condenser you described, I guess it is the original one. I did add a little more refrigerant and it did improve a little more. I am going to try to see how that works and start looking into a new condenser. Thanks for pointing me in the right direction.....