Anyone converted A/C from POA to accumulator type

[BobbyK]

As the title says.

The newer cars and trucks use a accumulator and preassure switch instead of a POA and preassure valve.
The newer systems are of course R-134 and not R-12.

Anybody done the conversion.

I'm not looking for the Walmart R-134 conversion kit either.

Pic's and details would be great.

[rickspickuppart]

here is the pictures, the picture of the eliminator is a little different than regular one we had them make it w/ out the other fittings so we could block off the oil return line. But normally they are a direct replacement. The second picture is were we normally put the orafice tube holder

[IMG]http://www.****************.com/boardpics/ac1.jpg[/IMG]
[IMG]http://www.****************.com/boardpics/ac2.jpg[/IMG]

[BobbyK]

So the orafice tube in the 2nd pic is the part inbetween the bottom evaporator core tube and the stainless flexable line?Correct?
Looks pretty bling bling!

[rickspickuppart]

yes, it is the piece between the fittings

[red71cheyenne]

So what does changing all that stuff do for you? I mean, is it colder, or what? When I had the guy charge mine last summer, he said that the 134 would not make it get colder, it would just be easier to get. And he had plenty of R12 since he is a shop. So I just left mine R12 and had him charge it up. Still gets plenty cold.

[rickspickuppart]

By getting rid of the POA valve provides the luxury of being able to run 134 (mainly because it's cheaper, 2.00 a can at Sam's Club), and by using an orifice tube and a low pressure cut out switch you can regulate where it cycles the compressor at more acuratly.

And by going w/ a Sanden compressor you gain alot in the area of power since they only take about 5hp to run as apposed to an A6 that takes somewhere around 30-35hp (also a new compressor is cheaper at 220.00 new and you don't have to have a core)

Also a sanden compressor works at an Idle instead of having to run t engine up to 1500rpms to get it to star cooling down in the cab, like you have to do w/ an A6

[red71cheyenne]

Cool. Sounds like a good upgrade. Now how much is this setup going to cost if you already have an existing R12 factory setup?

[Andy4639]

I changed all mine out with a later model truck unit, I think it was a late 80" truck, I bought a new compressor and aculator though, but I ended up with about $300.00 in all of it. I did go with the r-134A also, and it works fine, about 38-40 degrees in the hot summer days here in the South.

[rickspickuppart]

you would be looking at:
eliminator - 85.00
compressor - 220.00
oriffice tube and holder - 30.00 (not needed unless you don't want to run the expansion valve, and it does require welding on the correct fitting on the bottom of the evaporator)
brackets - 80.00


if you are missing any pulleys they would be extra
and you would have to have the hoses made

[ddsmith]

I couldn't sit back and watch this thread without providing input that has not been put out. It is not true that you have to change out a POA to run R-134A. The POA is adjustable to maintain a slightly lower pressure which corresponds to the proper satuation temp to maintain very cold vent temps. That is provided that the POA is not trashed. There is an easy way of determining if the POA is functioning correctly. It involves removing it from the system which would be required to perform the adjustment anyway. I would do everything I could to maintain a POA system if possible. Even if it means finding a working POA in the junkyard to do it The POA by design maintains the lowest possible temp in the evap(just above freezing) to give the coldest vent temps available. They didn't change the design of the system because it was better, they changed it because it was cheaper to produce. Which makes GM more money. The only reason I could see at using a POA eliminator would be because new POA's if available are going for big money. If you have any specific questions regarding how the A/C system functions and why the POA is an excellent setup, ask away.

[rickspickuppart]

I'm not trying to start an arguement (wish the board had a spell check because I am sure I spelled that wrong), but I have changed alot of them over and we have also tried using the original poa valve w/ 134 and it never worked as well in extreme temperatures (110 degrees +).

[ddsmith]

but I have changed alot of them over and we have also tried using the original poa valve w/ 134 and it never worked as well in extreme temperatures (110 degrees +).

Did you make the adjustments necessary to the POA or did you use it without adjusting it. If you did try to use it without readjustment I understand why it didn't cool as well. The saturation curves are different for R-12 and R-134A which requires POA adjustment.

[ddsmith]

red71cheyenne wrote

So what does changing all that stuff do for you? I mean, is it colder, or what?

The only reason that makes sense to switch to R-134A is the cost of the refrigerant. The systems are designed to function with R-12 correctly without any modifications. R-134A on the other hand will require changing out your accumulator, flushing the system out to remove old mineral oil which includes the condenser, the evap and the hoses, an adjustment if using a POA setup or purchase of an eliminator with pressure cyclying setup. Just so you all don't think I'm pulling this out of my a@@. Here is a link from the A/C forum that has plenty of information. http://www.ackits.com/forum/messagev...&threadid=7927

[rickspickuppart]

I can see this isn't going to be easy and it will turn into a heated discussion, I am not here to make enemies or upset people, so I will back out of the thread and in closing what I have done has worked for me.

[ddsmith]

rickspickuppart wrote

I can see this isn't going to be easy and it will turn into a heated discussion, I am not here to make enemies or upset people

Nor am I. I do believe that the discussion benefits all members. I did provide a link to an A/C forum and anyone interested in automotive a/c can benefit from visiting and reading. If anyone wants further information just ask.

[BobbyK]

I went through that forum 2 days ago.I spent about 4 hrs doing various searches.I read the opinions on keeping the POA VS converting to the system Rickpickupparts is talking about.

I am choosing the newer technology as most of my system is gone.I only have the evap. core and all the A/C ducting.Everything infront of the evap. core is gone,removed by the prev. owner.

I think if my system was mostly there and maybe only the compres. was toast I'd try and keep the orig. POA setup.

Hell I'll give it a try and let you guys know how it turns out.:p

[mrein3]

Originally posted by ddsmith
rickspickuppart wrote Nor am I. I do believe that the discussion benefits all members. I did provide a link to an A/C forum and anyone interested in automotive a/c can benefit from visiting and reading. If anyone wants further information just ask.

I'm with ddsmith on this one. In fact I'm in the middle of putting AC on a non-AC truck with all factory parts - including the POA and A6 compressor.

From what I've read and what I know, if you have a functioning POA keep it there after making the proper adjustment to it. The adjustment took me approximately 30 seconds. I spent about a half hour getting 30 year old fittings off, making the adjustment, and retesting the POA while looking at the readings I was getting on my AC gauges.

On my first, and hopefully last pass, I'm going to flush and use a used, original condensor. If the cab doesn't get cold enough I'm going to upgrade to a modern condensor designed to work with R134a.

Am I nuts? Maybe. I purchased enough R12 when it was legal to do so to do the truck many times over but what fun is that? The adjustment to the POA keeps the R134a at just above the freezing point which is a different adjustment than R12's point. This allows the evaporator to have the coldest possible refridgerant flowing through it.

In 1989 I opend up the R12 system on my '72 Chevelle, replaced the receiver/dryer, changed out all the o-rings, pulled a vacuum, and re-charged it with R12. That exact amount of R12 is still in the system and my glasses still fog up when I get out of the car to get the mail when I get home.

Reason #1 for going R134a: R134a doesn't get as cold as R12 but as stated in other posts it is way cheaper (and I believe that "R134a doesn't get as cold" is just a myth started by folks who did the Wal*Mart retro) . Reason #2 for going with R134a is that my truck's cab isn't nearly as large as my car's passenger compartment and it gets damn cold in my old car. #3 the A6 compressor isn't designed to be cycled on and off like the modern compressors that are. #4 I've had too many people say that it can't be done so now it is time to prove them wrong. #5 It sucks pulling my boat home here in Minnesota after a fishing tournament when it is 95 degrees and the humidity is 98%.

I'm taking digi-photos as I go so I'll write up a "how-to" when I'm done.

[ddsmith]

BobbyK,
I'm glad you've been there and looked through the info. i wish I had been there before going with my Old Air setup. I think I would have just bought the compressor, hoses, receiver/drier, and condenser. The evap size is small on the aftermarket units when compared to the original evaps. As you probably know the condenser is the issue when going to a R-134A setup. The original R-12 condenser doesn't have enough heat transfer ability to work well with R-134A. You may be able to provide forced air flow via a condenser fan to assist with heat transfer. If you go with a parallel flow condenser then the hoses will be the issue. Good luck. Let us know how it works out.

[beautimus]

could someone point me to a "how to" on the poa valve adjustment. and if there is a ballpark setting that will get you close? how about the hoses? i have heard that the hoses have to be changed to run 134a and some say not. whats the truth on this?

[Andy4639]

1. I want to say is anything you do must be done right are you will not get the same results as others.
2. I don't care about spell check on here. I know I can't spell good. I thought this was a truck board, not typing class.
3. I have the new R-134A and my system works great.
4. I still use the A-6 compressor and I do cycle it off and on.
5. I changed the POA out because it was going to cost me to much to buy a new one.
Why would you go to all the trouble to buy all new parts,compressor,hoses,acumlator,condensor, and so on, then use a 30 year old POA valve?
6. I did it because it was cheaper and I could do it myself.
7. I agree that the R-134A doesn't cool down as fast, but once mine gets there 38-40 degree's it stays there, weather I'm running 60mph or in traffic.
8. I have had this set up now for about 10 years in my truck. I have had to replace the compressor once, and that was because the water pump went out and bent the fan blades which then made the compressor go bad from wobble. I bought a new fan blade and have not had any more problems since. 5years ago
I'm not trying to make anyone mad just trying to say what I have done and works fine for me.
My truck has over 300,000 miles on it and I still drive it everyday.

[mrein3]

Originally posted by beautimus
could someone point me to a "how to" on the poa valve adjustment. and if there is a ballpark setting that will get you close? how about the hoses? i have heard that the hoses have to be changed to run 134a and some say not. whats the truth on this?

http://www.ackits.com/forum/messagev...AR_MSGDBTABLE=

I didn't have to turn the adjuster screw far to get from 29 to 26 on my gauges.

[BobbyK]

Good link.
I didn't see that one when I did my search.:p