How much do you pay for a new can of R12?

[AF1JZ]

3p: Two stage rotary vane with integral electronic measurement here, backing a turbomolecular and hot cathode ionization gauge for those really tough jobs. 10E-7 torr FTW

That sentence just gave me a headache reading. I wish I knew big words like that and actually be able to make a sentence :biglaugh: . I not soo smart. Just joking with you JJ.

 

[Ric]

Definately, Wally-World has kits for like $32
I just swapped mine, it was simple and works GREAT

It will for about a year til you need a whole new A/C system.

You need to do a system flush ASAP!!!!!!!!!!!!!!!!!!!!!!!!!1

 

[jetjock]

AF: I was joking with 3p. He's in the same business I used to be and works around that type of equipment all the time. Since it's a scientific business and the machinery does what it does on an atomic level it can have some pretty weird sounding names. It's not as if most people would recognize those terms.


Ric is right. People seem to be missing the point so I'll go over it again. It doesn't take a lot of effort or brains to make a system blow cold. You could fill it with propane and it'd do so. The trick is making it last.

Compressor death is the single most expensive failure of a MVAC system. When it lunches it'll contaminate everything. It's called Black Death in the biz. Repair usually involves complete system teardown, cleaning, and replacement of the evaporator, TXV, condenser, receiver/drier, pretty much everything but the lines. Not to mention the cost of a new compressor and refrigerant. For those unable to do the work themselves we're talking about a thousand bucks or more.

Simply put how long a compressor lasts is directly related to the quality of work done on a system. That's especially true when it comes to refrigerant conversions. It's a question of paying now or paying much more later. Do it right and your system will last a decade or longer. Cheat and your time will come. It may be a year or three but it'll come.

 

[Doward]

Autozone will rent you the gauge set, and the vacuum pump you need.

 

[Ric]

Just flush the system with 141b or whatever it is.. vacuum it out, put some r134a oil and gas in, and good to go.

It's not rocket science. Flush, vacuum, fill. As doward said, you can rent the stuff. You'll save yourself a grand in parts by flushing.

I'm no expert on the matter, but what I understand is, the R134 doesn't mix good with the R12 oil, ends up causing compressor death, which destorys the whole AC system.

 

[jetjock]

You're right. The problem is mineral oil is not miscible in 134. Since the oil must circulate with the refrigerant that means no lube for the compressor which will then start shedding parts of itself from day one beginning with its seals.

The key is to start with a clean system. That means a flush, PAG or Ester oil, no water vapor, and the proper charge. Purity of everything that goes into a clean and tight system is the key to long life. Plus doing it right means the system will stay closed for a long time. Generally speaking the longer it stays closed the longer it'll last.

The barrier hoses used with 134 aren't usually required because the old hoses are so impregnated with mineral oil they'll keep 134 leakage to a minimum. Even flushing won't remove this oil, which in that case is a good thing. That said if I was doing a full off restoration I'd replace the hoses with barrier. I'd also change to HNBR O rings if I was doing that but as you said for a simple conversion you can skip them. Still, when I had the system open to flush I'd replace the ones I could since HNBR kits are cheap and readily available.

 

[Ric]

The last car i just 134a refilled after doing a motor swap (already converted) and had to open the system.. I ran a 2/3 can thru the system with the high side port open then shut it and continued to fill to correct level.

Honestly, that car is still ice fucking cold. Not the best way, but vacuum pump was 3hr round trip away and couldnt wait.

 

[jetjock]

The old quickie purge trick eh? It won't get rid of all the water vapor but at least removes the air. The main thing is you had the right oil in there. I know others who've "gotten away" with this too. Problem is what water was left behind has now turned to acid and is eating the system. As I said it's not about blowing cold

 

[bmoss85]

if you are going to convert deff. do it right. 134 is much cheaper, but i dont think cools as well as R12.

 

[frontierguy25]

I Just use Freeze 12, It cools just as good, here in TX I do it every summer! And it is only $10 per can.

 

[Ric]

isn't RF12 what they use in europe? IDK how compatable it is with mineral oil

 

[jetjock]

I Just use Freeze 12, It cools just as good, here in TX I do it every summer! And it is only $10 per can.

I've explained the problem with Freeze 12 before. It's 80% R134 and 20% R142. R142 is miscible in mineral oil, that's how Freeze 12 gets away with being a "drop in".

The problem is you now have 20% of the refrigerant carrying the oil instead of 100%. This makes Freeze 12 a time bomb. When the 20% of 142 leaks out the compressor will seize. Since there'll still be pressure in the system from the 134 the protection normally provided by the low pressure cut out switch is gone. I don't see the sense of using a product that not only doesn't provide against compressor failure but actually promotes it. Plus it's 80% of something people were trying to avoid installing in the first place.

Not to mention most shops won't touch a car with an alternate refrigerant because they're required to have a recovery machine dedicated to it. Those shops that will work on them love Freeze 12 because it keeps them in business. As I said it's pay now or pay more later.