Does antifreeze run through our TJ's A/C compressors?

JeepinJake

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Hoping someone can solve a mystery for me...
My son has a 2000 TJ that is leaking coolant. Have put two different water pumps on it, and am ALMOST positive that the water pump is leak free. The leak doesn’t seem to be evident until the heat runs, and after drying off the ac compressor, it seams to be coming from ac compressor. When the heat is OFF, no leak. When I turn it ON, there is a very slow forming leak coming from the seal on the bottom of the compressor.

Heres the problem. I work part time at Autozone, and after explaining this to one of my co workers, he’s insisting that there’s no way coolant runs to the ac compressor.

Thoughts? And thanks in advance!
 

reddvltj

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What’s up crew?
Hoping someone can solve a mystery for me...
My son has a 2000 TJ that is leaking coolant. Have put two different water pumps on it, and am ALMOST positive that the water pump is leak free. The leak doesn’t seem to be evident until the heat runs, and after drying off the ac compressor, it seams to be coming from ac compressor. When the heat is OFF, no leak. When I turn it ON, there is a very slow forming leak coming from the seal on the bottom of the compressor.

Heres the problem. I work part time at Autozone, and after explaining this to one of my co workers, he’s insisting that there’s no way coolant runs to the ac compressor.

Thoughts? And thanks in advance!
Your coworker is correct. Engine coolant does NOT run through the AC compressor
 
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JeepinJake

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Your coworker is correct. Engine coolant does NOT run through the AC compressor
Ok, thanks so much. The ac compressor sure sounds like it’s engaging once the heat is turned on. I can here the clutch (very noisily) engaging every 20-30 seconds. Why would the ac compressor be turning on while running the heat? Also, could the leak I’m seeing be from the ac compressor be refrigerant?
 

reddvltj

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Ok, thanks so much. The ac compressor sure sounds like it’s engaging once the heat is turned on. I can here the clutch (very noisily) engaging every 20-30 seconds. Why would the ac compressor be turning on while running the heat? Also, could the leak I’m seeing be from the ac compressor be refrigerant?
Any time your heat/ac selector is in the defrost or a/c positions the a/c compressor will cycle on and off. In the defrost mode it is used to help remove moisture from inside the vehicle.
 

Hound Dog

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What’s up crew?
Hoping someone can solve a mystery for me...

I work part time at Autozone, and after explaining this to one of my co workers, he’s insisting that there’s no way coolant runs to the ac compressor.

Thoughts? And thanks in advance!
As our buddy Lunchbox Joe Biden would say "What a bunch of malarkey!" What does your co-worker know? How does it cool if it don't use coolant? Cracked that line open and get all that compressed air out so you can load up with a jug of antifreeze. Use the orange type though. Green is bad mojo for jeep air conditioners.
 
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JeepinJake

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And that moisture condenses around the AC tubing & appears to "leak". It's a normal thing.

Any chance this moisture is what your seeing? Did you taste it?
And that moisture condenses around the AC tubing & appears to "leak". It's a normal thing.

Any chance this moisture is what your seeing? Did you taste it?
i guess it could be moisture condensing around the tubing...but the leak is on the front driver side of the vehicle. I usually see the condensation I believe your referring to on the passenger side, towards the firewall. This leak is definitely green. Like I said, I’ve replaced the water pump twice in the past month. The second time was due to a bad pump. As far as I can tell, the pump is dry, but it is REALLY hard to get eyes on the bottom of it it.

The leak only seems to happen when the defrost is running. The compressor bearing and/ or clutch sound rough...could it be a seal gone, and leaking refrigerant?
 

TJ4Jim

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One thing you need to understand is that the heater core circulates at all times and there is no shut off or control valve, so turning the heat off or on has no effect on the coolant flow. It sounds like it could be the plastic top of the radiator is on it's way out, is there coolant or evidence of it under the hood.
 
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JeepinJake

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One thing you need to understand is that the heater core circulates at all times and there is no shut off or control valve, so turning the heat off or on has no effect on the coolant flow. It sounds like it could be the plastic top of the radiator is on it's way out, is there coolant or evidence of it under the hood.
Ok, thanks for that.

I guess the one remaining question I have relating to the leak being in concert with the heat running is if the ac compressor is running when the defrost is on, couldn’t this cause a refrigerant leak from the ac compressor?
 

Airjunky

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Yea, as someone said above, sounds like you have a leak above the AC & it's draining down. Probably a bitch to find, especially if your dealing with snow & butt cold temps right now.
 

Ct_tj

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Your best bet is to figure out what you're seeing leaking before replacing more parts. Coolant and a/c dye can both be green. Try smelling it before tasting it, because the ac dye/freon is a horrible taste that sticks in your mouth for a while. Try taking a pic and posting it for us to see.
 
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JeepinJake

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Yea, as someone said above, sounds like you have a leak above the AC & it's draining down. Probably a bitch to find, especially if your dealing with snow & butt cold temps right now.
I have a garage and a heater, so I’m good there. But your right, this has been a bitch regardless.😂🤦‍♂️
 
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TJ4Jim

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Ok, thanks for that.

I guess the one remaining question I have relating to the leak being in concert with the heat running is if the ac compressor is running when the defrost is on, couldn’t this cause a refrigerant leak from the ac compressor?
Engaging the compressor pressurizes the system up to several hundred pounds that can find its way thru just about any compromised joint, seal or gasket but if that is the case the compressor will stop engaging in short order as the charge will go flat.
 
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JeepinJake

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Engaging the compressor pressurizes the system up to several hundred pounds that can find its way thru just about any compromised joint, seal or gasket but if that is the case the compressor will stop engaging in short order as the charge will go flat.
Wow, awesome. Thanks so much. This also probably explains why the compressor is engaging so frequently, as well. It’s probably loosing pressure quickly.

So...he could run his heat without fear of causing his compressor to seize up, just NOT his defrost, correct?

Also, I’ve had a few people mention that I should just bypass my ac compressor. Thoughts on this? If I’m understanding this correctly, it would just result in a loss of defrost?
 

TJ4Jim

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Wow, awesome. Thanks so much. This also probably explains why the compressor is engaging so frequently, as well. It’s probably loosing pressure quickly.

So...he could run his heat without fear of causing his compressor to seize up, just NOT his defrost, correct?

Also, I’ve had a few people mention that I should just bypass my ac compressor. Thoughts on this? If I’m understanding this correctly, it would just result in a loss of defrost?
You can use defrost anytime you want, all the compressor does is provide air with a lower moisture content to aid in defrosting, defrost will still work fine as it does in Jeeps without factory air. When the system is flat the compressor will not engage to protect the compressor.
 

Blondie70

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I unplugged my compressor from the wiring to it. (at the compressor). Don't want to work on it rite now. Can run any setting on the dial with no compressor....but.....the settings where the compressor should normally run, cause the engine to idle up....not really a problem at all. Unplug it and forget about it if you don't need it for defogging, etc...
 

dimension12

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Refrigerant turns gaseous when exposed to the atmosphere. You wouldn’t see it collecting. Is the a/c compressor on the driver’s side?
How full is the overflow tank? That will push some out and look like a leak. Your best bet is to pressure test the system. Odds are great the upper radiator tank seal is failing. It could also be the overflow hose leaking.
 

reddvltj

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Refrigerant turns gaseous when exposed to the atmosphere. You wouldn’t see it collecting. Is the a/c compressor on the driver’s side?
How full is the overflow tank? That will push some out and look like a leak. Your best bet is to pressure test the system. Odds are great the upper radiator tank seal is failing. It could also be the overflow hose leaking.
Refrigerant does disperse into the atmosphere but the pag oil doesn't and could build up. That said, I think it would be pretty hard to confuse pag oil for antifreeze.
 
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