Air condition low and high side PSI?

2008 JEEP GRAND CHEROKEE LAREDO
259,000 MILES • V6 • 4WD • AUTOMATIC
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JOE1953
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the A/C wasn't blowing cold air. I checked the low side it was 15 PSI, so I put 12oz of freon in it, it went up to 45 PSI, is that a good number? I didn't check the high side what the PSI should be on the high side? the temperature is 35 °F at the left vent.
Jun 24, 2025 at 12:58 PM
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STRAILER
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The system was low that is for sure, the high side should be about 225 in about 75 degree weather. I the system seems cold there is a chance it is overcharged or under charged. Here is a video guide to help you:

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

Let us know if you need anything else.
Jun 25, 2025 at 11:20 AM
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JOE1953
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I vaccum the system for about 30 minutes and close the vaccum gague and pump and the gauge hold steady at 30 do that mean there is no leak in the system?
Aug 13, 2025 at 10:08 PM
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STRAILER
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Yes, this means the system is holding and ready to recharge. Let me know how it goes.
Aug 14, 2025 at 8:13 AM
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JOE1953
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what's the low and high side pressure should be?
Aug 14, 2025 at 11:33 AM
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STRAILER
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If you watch that video it shows the high and low side pressures. Depending on temperature the high side should be about 240 and the low should be about 40 in about 70 degree weather. I would stop once the the starts to get cold.
Aug 15, 2025 at 11:29 AM