Air conditioning installation

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Jul 16, 2003 | 03:02 AM

willowbilly3

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From: Black Hills of SD

Air conditioning installation

I have an old hang on a/c I want to put in my 68. I really haven't messed with a/c since the r-134 systems came out. Can you use these old units with a r-134 system? I understand you need a different dryer which of course I would buy new. Also I heard it takes a larger condenser. What compresser should I use? Any other advice would be appreciated. I want to do it as cheap as possible with junkyard parts.

Jul 16, 2003 | 03:49 AM

williamwilliam

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From: Bassett Virginia

Air conditioning installation

My a/c unit used r12 a while back, but had leaked down so I had to get it recharged. When I went they did a test to check it to see what was in it, and then charged it with r134. He told me that r134 was compatible with r12, which r134 has a slight mixture of r12 in it anyway. I didnt have to change a thing, and it is pretty cold, it tested out to be blowing around 36 degrees.

Jul 16, 2003 | 11:18 AM

rusty70f100

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From: Iowa

Air conditioning installation

I just got mine done, on the '70 F-100, and I used R-134a in it. One issue with R-134a is determining the right oil to use. I used ester oil in mine, and it causes the compressor to squeak ever so slightly when I just start out. Never does it for the rest of the day after that. I think PAG-42 is the right stuff to use? Anyone know for sure?

Edit: I had to route the heater hose holes lower to allow clearance for the under dash unit. In addition, I had to make a hole in the firewall just behind and a little above the carburetor to allow the AC lines to go through. Just look at the donor truck.

-Kurt

Last edited by rusty70f100; Jul 16, 2003 at 11:21 AM.

Jul 16, 2003 | 09:02 PM

Potent68

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Air conditioning installation

Yes, R-134 uses Pag oil. You should also change out all of your seals, as the R-134/pag oil eats away at them, and you will develop leaks over time. You can still get R12, and while it is more expensive, it works much better in the older systems, strictly because of the smaller size of the older systems. R134 doesn't cool as well, but when combined with a larger a/c system, it can be made to equal the R-12's cooling capabilities. I will be running R-12 in my system when I get home and fix my a/c on my new 71 F250.

Tom

Jul 17, 2003 | 07:35 AM

69crewcab

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From: East Norriton,PA

Air conditioning installation

You could always use HOT SHOT, its a safe replacement for r-12
heres an ad for it
Hot Shot (R-414B) is not just another R-134a enhanced blend. It is actually a unique blend of HCFC refrigerants that mirrors R-12 operating characteristics.

Hot shot, R-414B is environmentally, economically and technically SUPERIOR to any other refrigerant on the market today. It is the environmentally attractive, inexpensive and high performance replacement for R-12, R-134a and R-500.

Hot Shot is produced in 25lb. canisters and 10 oz. cans

I was given this tip from my works HVAC company we use.
WORKS PERFECTLY!

Jul 17, 2003 | 11:42 AM

rusty70f100

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From: Iowa

Air conditioning installation

Cool. Two questions though, does it use the same oil as R-12, and where can I get it?

Jul 17, 2003 | 03:09 PM

Potent68

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Air conditioning installation

The key problem I see with the "Hot Shot" stuff, or any other alternative other than R-12/R-134 is that it can cause your system to come up as contaminated when checked by any other place doing a/c. If this happens and they have to fix it, then it gets real spendy, really fast! Be weary. I specialized in A/C and electrical when I worked for Cadillac, so perhaps that's why I'm so skeptical. I will say my dad used the canned stuff on his wifes Cavalier he says it worked great.

Tom