PumpinIron

I'm relatively new to Jeeps. I own a 2000 Jeep Cherokee with 20k miles on a completely remanufactured motor.

The AC in my Jeep works. I know this because every time you turn it on the compressor engages and you can definitely feel cold air coming out of the vents. One thing that is leaving me puzzled though is lately it's been around 97 degrees every day and I notice that while the AC does blow much colder air than it is outside, it doesn't seem like it's as cold as it should be.

I've owned many cars in the past and on all of them the AC blew much, much colder air than the Jeep does.

I went to my local auto parts store and bought some R134a refrigerant which came with a pressure gauge to test the pressure of the AC system. The AC system was a tiny bit low on refrigerant but not by much at all. I filled it up to where it needed to be and the pressure on the system (according to the gauge) is right where it should be.

Needless to say the AC still doesn't blow as cold as I feel it should. I'm not sure what temperature the AC is supposed to blow at on the coldest setting, but if I had to guess I would say the coldest mine ever blows when I'm moving down the highway is about 74 degrees.

Like I said, it's definitely blowing much colder air than the air outside, but it seems like it should be blowing much colder than it is.

Am I just being paranoid or is there someway that the system can fail in which it will still work and hold pressure / refrigerant, but not blow as cold as it should?

Ideally I don't want to drop $1000 at a AC repair shop so I am trying to get opinions on what the culprit might be.

Turbo X_J

"I've owned many cars in the past and on all of them the AC blew much, much colder air than the Jeep does."

Climate control system in a Cherokee, sucks.

Be that as it may you are better off taking it to a shop before you cause a lot of expensive to repair damage.

PumpinIron

What do you mean when you say the climate control system sucks? As in I shouldn't expect it to blow as cold as previous vehicles?

I'm not going to cause any damage because I'm not messing with anything. All I did was refill the refrigerant (which is beyond simple). I don't plan on taking the whole system apart, just looking for culprits as to what could be causing this.

Hell, I don't even know if anything is wrong. I don't have another Jeep Cherokee to compare it to so I'm not even sure how cold it's supposed to blow.

Does anyone have any idea what temperature the AC is supposed to blow at using the coldest setting and max fan speed?

Muaddib420

It's supposed to be colder than 74. If your levels are OK maybe your blend door is stuck. The blend door is in the dash (pain in **** to get to) and mixes the cold and warm air. I find on hot days using the recirculate makes it a bit colder.

PumpinIron

Hmmm interesting thought. The blend door seems to work though. When I turn it to full hot it is definitely as hot as can be, then when I turn it to cold it gets cold, just not cold enough.

74 might have been an exaggeration on my part. I think it's safe to say its somewhere in the high 60s.

tiwvr1

Moisture in the system, a bad clutch fan, blend doors, over charged, under charged, these can all cause these issues.

Replace the reciever drier, vaccume it the system for a hour or so, see if it holds vaccume and then add the proper amount of refridgerant, to much oil will cause issues, as well as stop leak. This is why most of the time we say just take it to a shop instead of throwing parts at it. There are alot of small things that can cause a big diffrence.

Muaddib420

According the the service manual, at 100 degree ambient temperature the temp right at the center panel outlet should ideally be between 43 and 55 degrees. So you're maybe not that far off.

PumpinIron

Arghh, I have a feeling I'll be paying out the *** at a shop for this but it looks like its my only hope.

macgyver35

Actually, in 97+ models the AC and heat work rather well.

Blend door suggestion is a good thought. Also, making sure that the AC is on recirculate, and that the recirculation feature is engaging, as it will produce colder air than constantly cooling hot fresh outside air.

Go to Harbor Freight or some place and buy a pocket thermometer for $3-$4 and check it to be sure. How it "feels" is subjective. Crank her up to high on recirc and let it run for about 5 minutes to get the worst of the hot air out of the cabin, then check with the thermometer. 40-55, depending on ambient air temp, is a good reading.

Bbasso

I have a digi meat temp guage and see cold air in the low 40s sometimes 38 or 39deg on my 99 XJ.

PumpinIron

How would I know if the recirculating mode is engaging?

When I turn it on recirculating mode it blows cold air and I can hear the compressor under the hood engaging so I assume that means its working?

I'll buy a thermometer and check the temps in the cabin. Maybe it is colder than I think it is and I am just being paranoid.

Muaddib420

Put it on three or four in recirculate mode. You should be able to clearly hear the recirc blower under the glove box. Switch back and forth between recirc and regular AC. You'll hear it if it works.