AC not cold when Stationary?

supermike

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Since day 1 I felt the AC was not as cold as my 2018 JL. Today I was waiting for my gf and sitting at the parking lot and definitely felt the AC was just cool, not cold at all. I have ceramic window film all around including windshield, sitting under the sun at only 85 Fahrenheit, MAX AC wouldn’t even cool the cabin???
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blueweb

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Take it to a dealership or local shop to diagnose your AC problem.
 

Rico1111

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Make sure the recirculation button is on also! It helps a lot ...
 
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supermike

supermike

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Yes it’s recirculating I’m just trying to see if this is a 392 specific issue due to large amount of heat generated and lack of air flow at stationary…dealer is busy and my experience with FCA dealer is they usually creates more problem…
 

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If it works better when moving at a decent speed. Could be a coolant leak or something.
 

Rangemaster

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Since day 1 I felt the AC was not as cold as my 2018 JL. Today I was waiting for my gf and sitting at the parking lot and definitely felt the AC was just cool, not cold at all. I have ceramic window film all around including windshield, sitting under the sun at only 85 Fahrenheit, MAX AC wouldn’t even cool the cabin???
I have the same issue in my eco-diesel also. When your moving it works great, stopped and its just cool.
 

Rob97RR

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I have the same issue in my eco-diesel also. When your moving it works great, stopped and its just cool.
Same. I guess mine's not terrible when parked, but it's definitely colder when moving.
 

SLORubi

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Yes it’s recirculating I’m just trying to see if this is a 392 specific issue due to large amount of heat generated and lack of air flow at stationary…dealer is busy and my experience with FCA dealer is they usually creates more problem…
It’s not a 392 problem. AC units need air moving over the condenser to work, more air flow = more heat exchanged = cooler air output. Plus at low RPM the system is not moving the refrigerant as much. Add them together and you have a system that can’t keep up with the high outside temps.
You can try increasing RPM to see if the extra refrigerant circulation helps. Just a test, sitting at a red light or a parking lot revving your 392 is gonna send a different message.
 
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supermike

supermike

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It’s not a 392 problem. AC units need air moving over the condenser to work, more air flow = more heat exchanged = cooler air output. Plus at low RPM the system is not moving the refrigerant as much. Add them together and you have a system that can’t keep up with the high outside temps.
You can try increasing RPM to see if the extra refrigerant circulation helps. Just a test, sitting at a red light or a parking lot revving your 392 is gonna send a different message.
I totally agree with you. While my 3.6 is freezing cold at idle under the sun at 100 F. Just wondering if’s a 392/diesel thing.
 

Marine2146

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You could use the high idle “winch mode” feature of the tazer mini if your going to be parked often.
 

SSWIM

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It’s not a 392 problem. AC units need air moving over the condenser to work, more air flow = more heat exchanged = cooler air output. Plus at low RPM the system is not moving the refrigerant as much. Add them together and you have a system that can’t keep up with the high outside temps.
You can try increasing RPM to see if the extra refrigerant circulation helps. Just a test, sitting at a red light or a parking lot revving your 392 is gonna send a different message.
The newer ac units work well sitting still. The condenser/radiator fan pulls plenty of air. More so than ram air. I have 2 AC repair facilities. Yes it is more efficient at highway speeds like you referred, but still more than capable at idle.

My 392 works very well at idle. On a hot, 95+ day after sitting in the sun it cools down quickly and has no problem keeping the interior cool.

Mike, get yours checked. Something wrong with it. Mine works every bit as well as my 20 JL 2.0 did which was way good also.

Sam
 

BigGreen

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Yes it’s recirculating I’m just trying to see if this is a 392 specific issue due to large amount of heat generated and lack of air flow at stationary…dealer is busy and my experience with FCA dealer is they usually creates more problem…
2 weeks later "The other ones do it, too, performing as intended."
 
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