Automotive Air Conditioning Information Forum (Archives)

Provided by www.ACkits.com

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

Archive Home

Search Auto AC Forum Archives

Just installed used system, low is negative?

Jeep4Fun on Mon August 10, 2009 12:26 AM User is offline

Year: 1995
Make: Jeep
Model: Wrangler YJ
Engine Size: 4.0
Refrigerant Type: 134
Ambient Temp: 100+
Pressure Low: -
Pressure High: +150
Country of Origin: United States

I recently purchased a used AMA system. The system was working perfectly in the sellers vehicle when I bought it. I installed the system about two weeks after purchasing it. I pulled vacuum and everything looked good, no leaks? Then I started charging the system. I first tried filling the system with 24oz per the manufacturer. The system was not cooling and the pressures were not high enough. I then added one more can, total of 32oz, and little if anything changed. The low side was in the negative and the high side was +150, maybe much higher, don't remember exactly. I shut everything down and the pressures leveled out over time.

I double checked the install of everything and it all looks good. Blower works, clutch works. Any ideas? Like I said, everything worked perfectly before it was removed from the sellers vehicle.

TRB on Mon August 10, 2009 12:38 AM User is offlineView users profile

System uses 24 ounces of refrigerant. Adding more is just making what ever issue you have worse. Are you pulling a vacuum before charging? Do you have capillary tube attach to the suction line on the evap and wrapped with insulation tape?

-------------------------

When considering your next auto A/C purchase, please consider the site that supports you: ACkits.com
Contact: ACKits.com

Jeep4Fun on Mon August 10, 2009 2:17 AM User is offline

Yes, I pulled vacuum before charging. I have that coiled line from what looks like a t-stat the attached to the larger hose fitting and wrapped in insulating tape. Is that what you are talking about?

TRB on Mon August 10, 2009 9:38 AM User is offlineView users profile

Get the charge level back to 24 ounces and repost the low and high side readings.

-------------------------

When considering your next auto A/C purchase, please consider the site that supports you: ACkits.com
Contact: ACKits.com

Jeep4Fun on Mon August 10, 2009 7:56 PM User is offline

Low side is in the negative. High side is about 170. From what I'm hearing, it is most likely the expansion valve. Sound right to you? Can these go bad just by sitting for a couple of weeks in the AZ heat?

TRB on Mon August 10, 2009 8:28 PM User is offlineView users profile

Not normally, but if you're pulling into a vacuum, you have a restriction somewhere in the loop.

-------------------------

When considering your next auto A/C purchase, please consider the site that supports you: ACkits.com
Contact: ACKits.com

mk378 on Mon August 10, 2009 8:42 PM User is offline

Did you use a new receiver-drier? Do you have the receiver drier hooked up in the proper flow direction?

If there's a restriction somewhere else on the high side, the part just downstream of the restriction will get abnormally cold. All the high side lines should be somewhat warm all the way up to the TXV.

The TXV sensor bulb must be attached to the OUTLET of the evaporator, the line leading to the compressor. Not the line leaving the valve and going into the evaporator. After ruling everything else out, it could very well be a bad valve, they are a precision part with a small passage.

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.