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brookman
Posts: 1
Joined: Tue Jul 11, 2017 12:49 pm

questions

Postby brookman » Tue Jul 11, 2017 1:43 pm

2006 escape hybrid

I do A/C just as a hobby for me and some close friends, My friend came over complaining about poor cooling.

We live in AZ and it was 108 degrees yesterday. I hook up my gauges and at idle it is 50 on the low side and 200 on the high side.

I had him up the revs to 2000 and it went to 40 and 200. up to 3000 rpm and it was 35/200 .

Initially I was thinking overfilled , but as I thought more about it, with the high side never going up, it had to be undercharged.

I added about 3oz and the high side went up and it started cooling better.

So here are the questions. being low on r134 why was the pressure sitting at 50 on the low side, in my mind it should have been pulling down to the low cutoff and cycling.

Is there a fool proof method other than emptying the system and refilling with the required amount to determine the "proper amount" to add to a low system?

I also ran into something I had never seen on this vehicle and I am guessing it is to assist the hybrid function. I had him turn the key off after we did our pressure tests and the pressures never equalized, it stayed at 50 and 200 . I got to looking and I see a solenoid in line.

Thanks for any input!
Dougflas
Posts: 186
Joined: Mon Apr 18, 2016 6:10 pm

Re: questions

Postby Dougflas » Tue Jul 11, 2017 2:32 pm

Best way to verify a refrigerant charge is to recover and weigh the proper charge. As you get experienced, you can fudge it. In today's vehicles, the charge is small so a few oz can make a difference.
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Cusser
Posts: 271
Joined: Sun Apr 24, 2016 6:29 am

Re: questions

Postby Cusser » Tue Jul 11, 2017 4:03 pm

brookman wrote:I had him up the revs to 2000 and it went to 40 and 200. up to 3000 rpm and it was 35/200 .

I added about 3oz and the high side went up and it started cooling better.

So here are the questions. being low on r134 why was the pressure sitting at 50 on the low side, in my mind it should have been pulling down to the low cutoff and cycling.


Pressures at idle don't mean a whole hot. Looking at your pressures at 2000 and at 3000 rpm, not bad. Typically (I'm in Arizona as well, and not a pro) I see high side pressures closer to 250 psi in our temperatures, so you might be a few oz. low.

Typically, loss of refrigerant is due to an acute leak, but the systems are designed to leak a tad out the compressor seal; so if the 2006 has not had AC service ever or in a while, might just be slow attrition. So maybe add 3 oz. more and see if better/worse/same.

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