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post #1 of 9 (permalink) Old 06-05-2019, 03:53 PM Thread Starter
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AC compresser out?

My AC unit is showing the pressures in the attached pic. The clutch seems to be engaging when the ac is turned on, but it does not cool at all. Can I assume the compressor is out? What else could I check? Thanks.
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post #2 of 9 (permalink) Old 06-05-2019, 04:41 PM
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I assume thos pressures are with the compressor not running.

Operating pressures should look like the attached chart
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post #3 of 9 (permalink) Old 06-05-2019, 06:19 PM
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What was the temperature at the time?

2010 Equinox LT V6 AWD
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post #4 of 9 (permalink) Old 06-05-2019, 09:00 PM Thread Starter
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Attached is what I get now at 88 degrees out. It does not change when turning the AC on/off.
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post #5 of 9 (permalink) Old 06-06-2019, 07:32 PM
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So undercharged, should be close to 100 psi at that temp. The second scale from the center is temperature and should be pretty close to ambient when the system is static and equalized. I'm not finding any thing saying what pressure the BCM needs to see to allow the compressor to run. If you have a scan tool, you can check what the BCM is seeing for pressure. I suppose you could briefly jump the relay to see if the compressor comes on.

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post #6 of 9 (permalink) Old 06-06-2019, 08:04 PM
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You're saying the clutch is engaged and compressor is actually turning? No pressure change at all? Pretty unusual for a compressor to go completely dead but I'm not really up on the late model stuff with variable displacement compressors and controls. Is there actually a clutch?
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post #7 of 9 (permalink) Old 06-06-2019, 09:39 PM
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Expansion valve.
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post #8 of 9 (permalink) Old 06-16-2019, 01:55 PM
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Quote:
Originally Posted by Enoob View Post
My AC unit is showing the pressures in the attached pic. The clutch seems to be engaging when the ac is turned on, but it does not cool at all. Can I assume the compressor is out? What else could I check? Thanks.
Low pressure appears to be to high. Did anyone recently add freon recently. If too high, it was cause the compressor to kick-off.

Let the system remain idle for 30-45 minutes and see if both pressures equalize. If not, agree with the other member could be thermal expansion valve.
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post #9 of 9 (permalink) Old 06-18-2019, 11:43 PM Thread Starter
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So I hooked up the gauges and allowed it to sit for 45 minutes. The first pic had a temp of about 67 and the second about 64. I believe the slight drop in both gauges is due to the temp drop.


When engaging the AC switch, the inner part of the pulley spins. I believe this to be the clutch. It disengages when the AC is switched off. There is no change in the reading of the gauges when turning ac from off to on to off.



Puzzled as to why the pressures are remaining equal. If it was the expansion valve, I would think there would be some variance?? Still thinking compressor at this point. I do not have access to a scan tool.
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File Type: jpg AC reading 2 reduced.jpg (62.2 KB, 5 views)
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