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Discussion Starter · #1 ·
Ok I need help.

Long story short my AC still doesn't work. Finally got some useable info from the new shop I went to. Charged to correct weight, compressor kicks on/off a few times than stops. High side was about 225-250 low side was 10-15lbs. System does not equalize when shut off. Last year was a similar issue. Low side plunged, high side spiked and would blow out the relief valve quickly.

ALL PARTS were new last year when I did the AC initially. Used 4seasons products as they're easy to source locally to me from AutoZone.

I'm goin to try the low hanging fruit here and swap high/low switches and orifice tube as well as check evap core for blockage again. Compressor bad? Of all things I know minimal about hvac, though it is a simple system and not rocket science I don't wanna blindly throw parts at it. There was a fleeting moment last year whenI things worked as they should have, but it was only a few mins.
 

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Discussion Starter · #3 ·
I think kyou are on the right track with the Orifice Tube.

Picked jeep up today and spoke to tech. In summary the low side would sit at 10psi and high side would sit about 250. He said it seemed to strain when the compressor would cycle like something was plugged. Would not equalize when shut down and allowed to sit. Otherwise he said the compressor seemed to function fine and operated as it should when jumped out.

Should I try and flush evap core out? Its the only component I never changed. Should I be concerned about other components?
 

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Not sure the orifice is removable, it is in home systems where my experience is. But if it can be, do it. If not, you will probably need to replace the evap coil. It is a big job. But I think that yoiu are going to have to do it to have AC
 

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Discussion Starter · #5 ·
Not sure the orifice is removable, it is in home systems where my experience is. But if it can be, do it. If not, you will probably need to replace the evap coil. It is a big job. But I think that yoiu are going to have to do it to have AC
I do intend on doing the Heater Core/Evap, just not right now. I know minimal about A.C. at most. I understand the system enough to swap parts/get myself in trouble. At this point even if I can muster mediocre results I would be content, just enough to run with windows up in the event of a thunder storm to be honest.

I don't think there's any way to remove the orifice from the tube. Heading out now to mess with it
 

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Discussion Starter · #6 ·
Not sure the orifice is removable, it is in home systems where my experience is. But if it can be, do it. If not, you will probably need to replace the evap coil. It is a big job. But I think that yoiu are going to have to do it to have AC
Just as a secondary followup, orifice tube was 100% blocked. No idea on that, but I can't get anything to pass through it. New orifice tube has flow both directions. Used my high volume, low pressure tire pump to push through evap core and I'd wager it was full to the top with DYE/OIL. The amount of liquid that came out of it was astonishing. Did my best to clear it out, used my finger to plug one side and lightly pressurize and burp more stuff out. Everything seem seemed to be clean/sediment free out of it so I'm still at a loss for how the orifice was plugged solid. All other lines are clean as well.

Gotta see if I can track down a place to vacuum it down and try to charge it again.
 

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Discussion Starter · #8 ·
If it was full of dye, that is what probably caused the blockage. Once you get things flowing again you will probably be OK

AC works as good as my 2016 Ram! I am stoked!!!!!

Ironically the shop I brought it to today had called me with the same problems as all the others. High side ran up almost immediately....there's a blockage we can't charge it..... Idk why but I just didn't believe them. I had a $20 credit on my AutoZone account so on my way home I stopped and grabbed 2 of the R134a cans. Knowing it had been evacuated properly I added 1-12oz can and the system immediately kicked on and began blowing cool air. Not getting greedy and knowing the system potentially had an unknown amount of oil/dye in it I just ran it full blast while driving around to circulate it. Got home, checked it with the fill gauge I have and the low side was a touch out of the "recommended" range, everything still working like it should. I added small shots of the second can till it was at about 30-31psi on the low side, 90* outside sitting in the sun after driving for a while. Knowing I don't wanna over charge it having no real gauges and not having a thermometer to measure center vents I figure its as close to perfect as a shade tree mechanic can ask for. I have no idea why 4 shops had exactly the same issue but, as of this typing its resolved. We'll see if this holds true long term but today I'm calling it a win.
 

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Discussion Starter · #10 ·
Congrats. One good seat of the pants way to check charge is look at the metal fittings on the return line. They should draw moisture out of the air. Tradesmen call this a "good sweat"
I'll post a pic of the lines tomorrow since it's hard to describe but they look mighty sweaty! I have no idea what's been going on to be quite honest, all I know is it now works. I'm gonna cut into the old orifice tube tomorrow and see what was blocking it. Admittedly I had ZERO idea what I was looking for outside of being too stubborn to give up. The more I read about A.C. the more I'm seeing it's a super fickle system and I'm super intrigued! Never hurts to learn new information.
 

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Yes, very fickle and worse than any women. The earlier XJs like mine had what is called a thermal expansion valve which makes the system tolerate lots of variance in refrigerant charge. They are on all the new high efficiency home systems now. I wish they went back to those on all cars
 
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