Why does the A/C compressor line get hot?

2008 JEEP GRAND CHEROKEE LAREDO
127,000 MILES • 3.7L • V6 • 4WD • AUTOMATIC
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JOE1953
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I use a halogen leak detector to find leaks and the detector found one on the ac condenser, the pressure on my vacuum gauge drop from around 40psi to around 20psi. when I check the pressure in the system do I start engine before I connect the gauges?
Aug 18, 2025 at 6:52 PM
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STRAILER
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It is normal for the A/C line to get hot, please go over this guide to see how the A/C system works.

https://www.2carpros.com/articles/how-a-car-air-conditioner-works

This video will show you how to vacuum down and recharge the system.

https://www.youtube.com/watch?v=4EqdrBVb0sY

Please go over these guides and get back to us.
Aug 19, 2025 at 1:19 AM
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JOE1953
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I still have a Freon leak in the system I check the pressure with the engine off the psi was around 40.
Aug 24, 2025 at 2:51 AM
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STRAILER
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Yep, you have a leak, please start a new question for us to fix it, we only handle one problem per thread, please post your new question here, you must be logged in.

https://www.2carpros.com/questions/new

Cheers, Ken
Aug 24, 2025 at 3:53 AM
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