All,
I finally replaced my AC system with a new compressor, orifice tube and dryer. I bought the parts and took them to a local shop to have them installed with R12. The guy charged me $40/lb for the R12 and I decided to go with it. This was in December. I took the car out last week and turned on the AC and it blew hot air. I took it back to the shop and it was found that the schrader valve/o-ring on the high pressure side was leaking and the cover was the only thing keeping in my R12.

The guy unfortunately had no more R12 when he recharged the system and said the replacement that he was able to get was RS-24 (R426A). Is this stuff ok for the car? It's advertised as great for automotive use. It cools decently when driving, but I'm not too sure about it's cooling ability in traffic or slow moving. I had it recharged yesterday, so I don't have much experience with it yet.

Was this a good move? What should this stuff cost per pound? Thanks

 

Don't reall know anything about the coolant, but found out from experience that you should try and run the compressor either on AC, or defrost in the winter, at least 5-10 minutes every month. It seems to do a better job of keeping the seals lubricated with the oil and keeping it sealed in. Mine leaked out after maybe 6 or 7 months of nonuse, but since I've been running it a little every month, it's held well for a couple of years. I was told this, and don't know if it's based on fact, but has worked for me

 

search r406 autofrost that is what you want to use i think

 

I just bought some R12 on Craigslist. I have 609 cert. but if you look around, you can find someone cleaning out garage who may sell it to you. The small 12-14 oz. containers usually sell for 15 to 20 bucks each.

 

R-426a looks to be sort of in the middle compared to R-12 and R-134a. It has a warmer boiling point than R-12 but a colder boiling point than R-134a (Colder numbers are better).

Critical temp is the same as R-134a. So stuck in a traffic jam, you may run into issues once the condenser gets too hot (no phase transition = no cooling)

Says it's compatible with both mineral oil and POE oil, but as far as I know, the HC blends are the only refrigerents which can do both. Freeze 12 says it runs in both. But both R-426a and Freeze 12 have R-134a in them (which is only good in PAG or POE, never in mineral oil)

The 0.5°C (1°F) "glide" in the condenser is essentially the same as a non blended, single refrigerant (like R-12 or R-134a). As the single refrigerants have zero glide (only one temp/pressure where the phase changes in the condenser)......A higher glide means that the phase change can occur at multiple temperatures inside the condenser. What this means it that a higher glide uses more of the condenser's capacity to shed heat at any given time. This is one of the reasons that Autofrost can cool so darn well.

To put this into perspective with some numbers.

Boiling point (lower is better)
R-12 = -21°F
R-134a = -15°F
R-426a = -19°F
R-406a = -28°F

Critical temp (higher is better)
R-12 = 233°F
R-134a = 213°F
R-426a = 213°F
R-406a = 238°F

Glide (higher is better)
R-12 = 0°F
R-134a = 0°F
R-426a = 1°F
R-406a = 15°F

 

Just for giggles, the boiling point of R-22 and R-290 (propane) are both -44°F.

55% of whats in Autofrost is R-22.
The HC blends run around 50-60% R-290 (propane)

It's what gives them the high performance.

 

I know this is a little off topic, but what side is the suppose to go to the condensor (high side). Im doing a swap and using the third gen compressor on an ls1 in a 280zx. I just need to know what side goes to the condensor, and what side to the evaporator. Thanks