Posted by jdemaris on July 23, 2008 at 09:11:27 from (67.142.130.38):
In Reply to: Re: auto a/c posted by Allan In NE on July 23, 2008 at 08:21:26:
I just went through that - sort of - on a 98 Dodge Grand Caravan with front AC only with optional HVAC computerized controls.
Put a new compressor and dryer in it. The previous compressor had a slow shaft-seal leak - i.e. it wasn't trashed.
Got all done - pulled a vacuum for two hours and then charged exactly to specs - 34 ounces of 134A. Then ran it - it would blow cool air at first (cool - not cold), and then get warm after five minutes. I checked low side pressure and high side pressure against outside temps. Also checked high-line temp. All checked in-range as to the factory book. Dodge provides one of the most comprehensive charts I've seen with all pressures at all line temps, evaporator temps, and air temps.
Everything checked pefect but the thing would not cool. In perhaps a stupid bout of desparation - I added an extra 12 ounce can - and the duct air temp went down from 68F to 58 degrees F (on an 80 F degree day). I then added a second 12 ounce can and the duct temp went down to 50 F degrees. So - I got all done and it now works pretty well. It passed the computerized cool-down test. Low and High pressures with the two-can overcharge still pretty much read the same as before - with the low side slightly higher.
I've got no answer to this one - except it now works and I'm going to leave well enough alone.
I had been suspecting that maybe some of my 12 ounce cans - some 10 years old - were maybe not completely full? Well, now I doubt it. I checked one - 15 ounces full and 3 ounces empty - right on the nose.
It was running 38 PSI on the low, and 270 PSI on the high at 85 degrees F. Dodge factory manual says that at 80F - normal is : low at 17-35 PSI and high at 230 - 360 PSI. Air coming out of the AC duct should be 38F to 50F.
This one's a bit beyond me - but it's working good enough for now - especially since I'm sick of working on it.
We sell tractor parts! We have the parts you need to repair your tractor - the right parts. Our low prices and years of research make us your best choice when you need parts. Shop Online Today. [ About Us ]
Today's Featured Article - Talk of the Town: Winterizing Engines - To Drain or Not to Drain? - by Russ Berry. What is this strange attraction I have to equipment and machinery? How did I get this way? I came from the suburbs and own a small horse farm in rural Loudoun County, Virginia. You can call me a "weekend farmer." The local farmers do. Does it bother me? No. I am just happy to have their friendship. At least the word "farmer" is in my title. But what is the attraction? How can I explain the sensation and exhilaration I feel when I turn the key and hear the engine come to life (most
... [Read Article]
Latest Ad:
2022 John Deere 5045E, 4wd, front end loader and 3rd function with grapple. 120 hrs, 55k new, must sell
[More Ads]
All Rights Reserved. Reproduction of any part of this website, including design and content, without written permission is strictly prohibited. Trade Marks and Trade Names contained and used in this Website are those of others, and are used in this Website in a descriptive sense to refer to the products of others. Use of this Web site constitutes acceptance of our User Agreement and Privacy Policy
TRADEMARK DISCLAIMER: Tradenames and Trademarks referred to within Yesterday's Tractor Co. products and within the Yesterday's Tractor Co. websites are the property of their respective trademark holders. None of these trademark holders are affiliated with Yesterday's Tractor Co., our products, or our website nor are we sponsored by them. John Deere and its logos are the registered trademarks of the John Deere Corporation. Agco, Agco Allis, White, Massey Ferguson and their logos are the registered trademarks of AGCO Corporation. Case, Case-IH, Farmall, International Harvester, New Holland and their logos are registered trademarks of CNH Global N.V.
