Are these pressures high?

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72gmc4x4
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Are these pressures high?

Post by 72gmc4x4 »

2005 PT Cruiser
106* outside temp in the shade.

This is the second time I fix an AC so not too familiar with what pressures/temps should be especially since everything else I've read or seen are in environments where it doesn't get nearly as hot as in the AZ desert.

So, the AC wasn't cold, just cool, even after driving a while. I replaced a low side schrader valve since the line was wet(oil and dirt) around it yet everything else was clean. I pulled a vacuum, 28mm of hg for 30 min, it held the vacuum for about 10 min before I charged it. I added 1lb and 2oz which is what the label under the hood stated. (new 30lb tank on top of a shipping scale used to measure weight)

I get in the car and rev it to 1500rpm, doors open, fan on high, recirculate. Not in the shade because there is none to be found where I was working and I get 55* at the vent. 51* temp drop and that's in direct sunlight.

I leave the car idling and I believe the gauges read 65/350. I read that is an air flow problem. Is this correct? The condenser is full of bugs.

I test drive the car and only a mile down the road the AC feels cold and vent temp is 45*.

I am curious to know if those vent temps and pressures sound correct or if something is wrong...
mk378
Posts: 77
Joined: Tue May 24, 2016 5:53 am

Re: Are these pressures high?

Post by mk378 »

Cleaning the condenser would certainly help. If there are a lot of bent fins from the larger bugs and small rocks, consider replacing it. But you can run what you have it's not too unusual to be pushing 350 in triple digit heat.
jeepsj
Posts: 77
Joined: Mon May 16, 2016 1:41 pm

Re: Are these pressures high?

Post by jeepsj »

Some 409 cleaner on the condenser and flush from the back side with your hose will remove a lot of the dirt.
99 Jeep XJ
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72gmc4x4
Posts: 41
Joined: Wed May 04, 2016 11:19 pm

Re: Are these pressures high?

Post by 72gmc4x4 »

Thanks for your replies. I will definitely clean that condenser out today.
72gmc4x4
Posts: 41
Joined: Wed May 04, 2016 11:19 pm

Re: Are these pressures high?

Post by 72gmc4x4 »

I've been having issues with this AC. The AC stopped working. A connector for the climate control was fried so I replaced. A day later it stopped working. Before I get back to the car, the owner has someone else look at it. Turns out it blew the fuse so it was replaced. A day later, the fuse blew a second time. The owner realized the wrong size fuse was used. Put in the correct fuse and it's been working great since.
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