No low pressure

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chvet73
Posts: 7
Joined: Wed Jun 13, 2018 8:56 pm

Re: No low pressure

Postby chvet73 » Wed Jun 20, 2018 8:14 pm

Here is an update with the gauge knobs closed. System running. High side 90

Now the low side showed a vacuum of 22.

As always thanks in advance for your answers.
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bohica2xo
Posts: 423
Joined: Wed May 11, 2016 4:12 pm
Location: Las Vegas, NV

Re: No low pressure

Postby bohica2xo » Thu Jun 21, 2018 6:59 pm

You need to take it someplace & have it recovered. See how much charge is in it.

You need to find a wiring diagram, and find out why it allows the low side to run in vacuum.

You need to pull the expansion device out & find out WHY it is blocked.

Nothing appears to be wrong with the compressor, but keep running it that way & there will be.
chvet73
Posts: 7
Joined: Wed Jun 13, 2018 8:56 pm

Re: No low pressure

Postby chvet73 » Tue Jul 03, 2018 9:11 pm

Just thought I’d post a final report on this. Had it finished at a local shop. Here’s what was found. Blocked expansion valve. Dryer had the desiccant loose inside which is what plugged the expansion valve. You could here it rattle. Also a leaky oring on the condensor. New valve, dryer and recharge and seems to be just fine.
Thanks all for your input.
JohnHere
Posts: 82
Joined: Sun May 13, 2018 10:20 am
Location: South Carolina Upstate

Re: No low pressure

Postby JohnHere » Wed Jul 04, 2018 6:50 am

I had that happen to me once many years ago, very similar to your situation. In the car I was working on, the dessicant bag had ruptured inside the receiver dryer and sent the loose beads down the high-pressure line to the expansion valve, plugging it and the line. Glad you finally found and fixed the problem.
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Cusser
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Re: No low pressure

Postby Cusser » Wed Jul 04, 2018 7:13 am

chvet73 wrote:Just thought I’d post a final report on this. Had it finished at a local shop. Here’s what was found. Blocked expansion valve. Dryer had the desiccant loose inside which is what plugged the expansion valve. You could here it rattle. Also a leaky oring on the condensor. New valve, dryer and recharge and seems to be just fine. Thanks all for your input.


Sounds like the shop knew its stuff. I hate taking in a vehicle to the mechanic's shop for any reason (I use an independent ASE mechanic when I do), but sometimes their experience and better equipment can help a lot.
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bohica2xo
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Location: Las Vegas, NV

Re: No low pressure

Postby bohica2xo » Wed Jul 04, 2018 9:48 am

Yep.

Plugged TXV as predicted.

Glad you got it fixed.
chvet73
Posts: 7
Joined: Wed Jun 13, 2018 8:56 pm

Re: No low pressure

Postby chvet73 » Thu Jul 05, 2018 10:59 pm

Thanks again for the help. I hate to pay someone too but since I have no ability to discharge a system, I decided to do it the right way. If it was empty I would of gone into it. They had to match an expansion valve as the original was not available. They are an old fashioned a/c and radiator shop. I’ve had them rebuild radiators before. So I knew they were honest. The last place near me that can rod out a radiator.
JohnHere
Posts: 82
Joined: Sun May 13, 2018 10:20 am
Location: South Carolina Upstate

Re: No low pressure

Postby JohnHere » Mon Jul 09, 2018 10:44 am

Nice diagnosis, bohica2xo. You nailed it earlier in the thread :mrgreen:

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