A\c Works For 30 Mins

[sarge844]

A\c Works For About 30 Mins Fine 99 Jeep Sport

Then It Seems To Shut Off Warm Air Only I Shut It Down
About 20 Mins And Its Ok Over N Over I Changed A\c Relay
No Change ????? Help ! Thanks

[AlohaBra]

Originally Posted by sarge844

A\c Works For About 30 Mins Fine 99 Jeep Sport

Then It Seems To Shut Off Warm Air Only I Shut It Down
About 20 Mins And Its Ok Over N Over I Changed A\c Relay
No Change ????? Help ! Thanks

HEY...a whole bunch of peoples have this problem....
See the threads....
My AC compressor on my 97 Sport just broke a shaft this week in 105 deg. weather....
Try add one can of R143a.....use a gage kit.

[4x4grey88]

Have you check how much charge is in the system?

When an A/C system cools and warms it normally mean low freon.
Because it does cool in the first place tells you that there is freon in the system (i.e. no major leaks).

Being that you have a newer Jeep the A/C system should have R-134a freon.

You can purchase freon booster/fill cans from places like Wallymart pretty inexpensive. Some come with gauges to tell you how much pressure is in your system. This beats paying a shop to do the same thing.

Keep it cool....

[JDPascal]

this could be caused by:

1. the evaporator frosting over after a short period of use due to low evap temp and high humidity.

2. a frozen expansion valve or plugged orifice tube.


Try turning the controls to - FAN=medium, Temp= low, and air source to RECIRC. If it still quits cooling after 30 min, the problem is likely in the system (expansion valve or orifice). If all is now ok, it was a temp setting/humidity situation.

JD

[AlohaBra]

Originally Posted by sarge844

A\c Works For About 30 Mins Fine 99 Jeep Sport

Then It Seems To Shut Off Warm Air Only I Shut It Down
About 20 Mins And Its Ok Over N Over I Changed A\c Relay
No Change ????? Help ! Thanks

Was searching the web for issues and found this:

1997-2001 Jeep Cherokee: Reliability
Trouble Spots

Consumer Guide's® Auto Editors have scoured repair bulletins and questioned
mechanics to search for commonly occurring problems for a particular vehicle. In some cases we also give possible manufacturer-suggested solutions. In many instances these trouble spots are Technical Service Bulletins posted by the manufacturer, however, we have our own expert looking at additional vehicle problems.

Air conditioner : The air conditioner gradually stops blowing cool air because the evaporator ices up. Replacing the low-pressure cycling switch usually fixes it. (1997-99)