My A/C is blowing hot. It blew a compressor, that has since been replaced. The unit has been evac'd and had 2.5 pounds of R134A put in the system. Why is it still blowing hot? Do I need to be looking at the expansion valve ( not real sure where to look for that ) or some other similar item I'm apparently missing? I know the pressure should be reading about 40-45 PSI, but it's showing a pressure of 100 PSI. If I bleed the pressure off to bring the pressure down it doesn't help. There are no leaks in the system, but I'm afraid that if it continues at higher pressures I will eventually burn up this compressor ( or worse ). Chilton's and Hayne's both say to replace the dryer ( accumulator ) when the compressor is replaced, but experience and training in the past has taught me that this is not necessary, as long as the system is evac'd and fresh charge of oil and freon.
Breathing issues aside, it is just plain uncomfortable to drive this bugger at this time of year without A/C, and it does make it easier for me to breathe ( asthma ) while driving. Prior to the compressor going south, it was a right chilly A/C unit.. What am I missing?
I'm going to have to assume a couple of things..... the pressures you are reading are low side pressures?? and that the old compressor was replaced with no other work (other than the recharge) to the system??
When a compressor fails internally there's all kinds of little bits and pieces that used to be compressor that infiltrate the rest of the system. I think that you'll find (at the very least) that the orofice tube and condenser are both plugged off. If you are real lucky, none of this crap has made it around to your new compressor (the viscious circle starts here).
I'm not sure who is training folks to avoid servicing the rest of the system when replacing a pooched compressor but I think you are seeing the validity of "cutting costs" in this manner. When I replace a compressor because of an internal failure, the car gets a new condenser, orofice tube and receiver/drier...... there is no way on Gods green earth that I am about to risk giving away free parts and labour because I didn't do what should have been done. Additionally, the evaporater core is back flushed as are all the hoses (though I have changed hoses with mufflers in them). If all of the old stuff isn't spotless clean inside, we are only rolling the dice to see how long before we repeat the process.......
We need to remember that these compressors aren't compressing liquid, they are compressing a gas and, as such, their internal tolerances are really very fine. It doesn't take much wear to have a system that just doesn't perform well enough to keep most customers happy. Like I keep saying, I'm spendy.... very spendy - but after the sticker-shock wears off, my customers are happy.
Back to your problem.... if I were presented with your car in it's current state, I would replace the "usual" parts and, quite likely, the compressor.... in my mind, it is now suspect and I would have some real concerns about offering any kind of warranty (or even releasing the car) with what amounts to a ticking time bomb under the hood.
If you will be performing the work yourself, I'd suggest replacing the "usual" parts and flushing the remainder of the system very, very well. Ensure that the correct amount of oil is added and evac/recharge.
I realize that this is an old car and that pouring this much money into it may not be financially feasable, but it makes less sense to waste money through inadequate repairs.
I have to agree with Jim. Your desire to save money does not make parts serviceable.
When I worked on AC, I often had customers tell me that, *because they wanted to save money*, parts were OK, and didn't need to be replaced. It just doesn't work that way. When a compressor goes, it often grenades, spewing metal everywhere in the system. That metal must be removed; if that means replacing parts, that's part of the cost of having AC that works.
Not much can be added to Jim's advice, except to question whether a 92 was a
134 system or still R12 ? I *thought * they didn't go to 134 until 93/94 on the Aerostars. IF that's the case, and there's a swapover involved in the process as well, there's a whole other host of reasons to replace darn near everything !
Also, many A*'s had a REAR evaporator and thousands of miles of hoses as well that must be flushed.
Well, you're dealing with a pretty bitchy pump in this case. Thanks Ford!
My experience was similar. I believe what happens is the R12 oil vs the R134A might create a flammible substance. When my system did what you're describing I found a LOT of crud in the system - enough to totally clog the condensor ($$) and orface tube. I found sludge, metal, and plastic...
#1 - tear it all apart, clean every inch of it with LOTS of 92% rubbing alcohol (any pharmacy will have it). This includes the upper hose set. I'm still using my original factory upper hose set - its survived the abuse of R12, R134A, and severe overpressurization. Be careful not to expose yourself to too much of this stuff, it will kick your ass in a not so happy way.
Once clean, you should find 'not much' back pressure on any given part...
#2 - I found my condensor was clogged up and would not unclog. Apparently pump-bits found their way into there... $150 later the system worked nicely.
#3 - replace the orface tube. This is at the coupling by the passenger exhaust manifold between the flex hose and the condensor. Removing the airbox will get you pretty easy access. They call for a tool to remove the orface tube, personally I was able to get at it with some grippy hemostats
#4 - replace the dryer. Bloop there goes $30.
#5 - drain pump carefully, fill with R134A friendly oil, drain, refill, etc... until what comes out is clean. I was too chicken to pour alcohol into the pump IIRC (hey, its been a few years).
#6 - replace all o-rings with green ones (black O-rings don't like R134A friendly oils) re-oil everything with PAG or whatever (the R134A friendly stuff), and recharge.
#7 - engine overheating at idle with the A/C on. Needed a fan clutch.
#8 - after all the drama my pressure switch was leaking (would kick the compressor off when the system had plenty of pressure, I guess the diaphragm had a hole popped in it). I wanna say that cost me $8
Also ONLY REFILL THE SYSTEM WITH 70% OF ITS R12 CAPACITY. Overfilling R134A seems to cause some really odd things to occur.
Personally I didn't have access to a pump to pull the system down with, so I went ahead and left in "one atmosphere" of moist texas summer air... I'm sure it didn't do the system any favors, but hey it works.
Officially my AC repair has outlasted two transmission overhauls. on a
95F day it blows 37-40Fish at highway speed on panel air, next to the top fan setting. On a 90F or cooler day, it'll hang near freezing.
Okay, replace the accumulator. I debated doing that today. I probably should have. Rather, I removed it, and checked to see if I had a decent flow through, which, I do. There doesn't appear to be any debris floting around, the oil wasn't emulsified, but rather clear ( aside from a bit of green dye ). The old compressor had simply ceased to continue operating. No bang, ka-boom, just a froze up without warning. I had it all checked yesterday and they mech said it was likely the accumulator or expansion orifice, same as you, and that the compressor was good...but *I* waited for your answer. So I guess teh next item is another accumulator/dryer unit.......and where exactly is this orifice of which you speak. My Haynes manual says it is replaceable, but where is the little booger at and how do I get to it? I spent most of my day in 100 degree heat resolving issues so I could check the unit, so not it is easier to get to to replace ( I really hate working on old stuff that hasn't been touched since it was built..parts are usually stuck or rusted in place and a real bear to remove or replace.
"Jim Warman" wrote in message news:go9Lc.46424$2i3.27943@clgrps12...
It was R12, now R134A. Yes, lots of hoses and stuff, butit has ben evac'd and flushed, as it were. I like to have people take care of things I don't have tools for, simply because I don't like buying parts repetitively....better to replace it and have neessary stuff done. As I had said, the pressure is 40-45 on the LP side. I don't have a fitting to gauge the HP side.
Actually, the last compressor ran excellent...right up until it seized (????) Since I knew I was going to lose the R12 charge, I went ahead and converted. I didn't find any debris floating around in the system, but I may yet be surprised. Since I hadn't pulled the orifice as yet, that may be next, but since Jim and Chief suggested replacing the accumulator as well, I suppose I should. After all, is said and done, I'm a computer geek. I have had to deal with refrigeration systems in over 20 years. You managed to get a cool system and not evac the system? I've never had real good luck with that. I'm impresed. The Nebraska humidity puts Florida and the deep south to shame. It's bloody miserable today...100 degree heat and 72% humidity.
"Jacob Suter" wrote in message news:DnjLc.112078$ snipped-for-privacy@fe45.usenetserver.com...
John, not to sound belittling, but the reason the orifice tube and the dryer are replaced is not to make the mechanic rich, but to get EVERY last bit of contamination out of your A/C system. I'm having the dryer and orifice tube replaced along with the leaking evaporator on my Explorer. A $600 job, but the compressor alone for a Explorer can cost that much. Before you do anything else, do the job right by flushing the system, putting in a new orifice tube and dryer, and then recharging the system. Anything else is false economy. Besides, it sounds like you are doing the work yourself, the parts and refrigerant shouldn't cost more than $150 max.
Good luck. I feel for you, this Florida sun is a bitch.
I think this one is a lost cause... maybe once he sweats enough he'll lower the lazyness level a bit.
The pump is the expensive part, its also the fragile part. Lookin around online the dryers have gotten quite a bit cheaper, the orface tube is only a couple bucks, an 6oz bottle of the correct oil for R134A use is like $3.50, and all the o-rings required might cost you $2.50...
If the condensor is loaded (I bet his is, he's just as hard-headed as I was) the price just went up about $100-150.
The whole thing is a 2-3 hour job. Mine has worked fine for 2 years now, no leaks (ok, its a half a can down after 2 years, big woop) or hassles. It's sure nice to jump into the car and cool off right quick.
S'alright, Richard. I asked for the help, remember.
Yes, it was dumb not to do it, but it is done. I went through and pulled the orifice tube ( crapped up badly and has been replaced ), flushed the lines and cores with alcohol, blew everything out, and have ggod flow through the system. My next move is to try another compressor. When I pulled this one out to flush it out, it had no oil in it ( zero, zip, nada ), and spins freely. So I can only imagine it is not pumping or compressing. With no oil, it can't be good, but I did recheck the orifice tube and no crap in it now.
I don't know what you are calling laziness. but I have been two days in
100 degree heat, 70+% humidity trying to work on this pig with no diagram or decent desciption to go by. My last experience with AC&R is over 20 years ago.....so if taking the initiative is laziness, especially when I am a computer geek by trade and profession, call me lazy. I'm out of work, running out of money, my meds alone are over $1200 a month and trying to get by. Sarcasm is not appreciated.....Capeesh? ....and yes, I am doing the work myself out of necessity. I'm a pretty damned good mechanic when I have stuff to work with. What I am lacking is is information, which I have politely asked for....which reminds me....
Well, after two days of clueless work, I finally managed to get the booger to work. Some of it was repetitive, but thems teh breaks I guess. The orifice tube was crapped up, the accumulator was not ( drained oil anyway and checked for particulates - none ), replaced the compressor a second time.....now all is as it should be adn running very cool at 45 degrees and
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