Engine Custom A/C. How to determine correct amount of freon?

Ray65-71-73 said:

First, the reason I tried it was because I have long suspected that Enviro-Safe IS propane.

And I don't use alternatives for money. It is for performance and versatility. Enviro-Safe, and possibly propane, works in both R12 and R134 systems, so I don't need to mess with "conversions" and it works better.

We don;t seem to worry about gas leaks. We treat them as a simple nuisance. But when gas leaks it comes out as a liquid and stays liquid for some time. I will not put a rubber fuel line over an engine. But I have had rubber AC lines blow off over an engine. If the whole three pounds of propane leaked out it would flash off and be gone.

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I applaud that, and I actually think it's pretty cool that it may be even more effective than R12 or R134 and it's safe for the environment. All those points make sense. If you and a few others don't die, then I'll reconsider.... at some point.

RaggedGT said:

I think R134a will do just fine in the Sloth (#Throwback- I don’t remember what you are calling the car theses days lol.)

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That's funny

For black jack the 12 second hatch, Garfield my big orange 7.3 power stroke, Grover the 93GT (from GroverDill + it's blue and I liked Sesame Street as a kid), and Kandi (a good wholesome stripper name for the vert that has been ridden pretty hard and came with a loose top, the names fell right into place and stuck. On the 91, I've tried Man O' War because it was a fast race horse that looked black because of the pictures but no one gets it and it felt too self-indulgent, Sloth because it took forever to get going as a project, and now snake pit because there's a complete cluster of hoses, lines, and wires everywhere, the names just haven't stuck. I suspect snake pit won't last, because I'll eventually clean it up.

I don't care if it's juvenile. I like naming 'em. And don't tell GroverDill since he never named it.

Just looked into this a bit today as I bought 12 cans of R134a, and I noticed another brand Zero R Z134. It is apparently flammable, but I want to know more as amazon users are saying it's significantly outperforming R134a. I don't need anything better than R134 in my Fords because they can alread freeze me out. However, the Saturn could use some help. The Saturn's A/C doesn't seem to blow off due to high pressure like the mustang does. So, I *might* consider using a different refrigerant next time.

Anyways, here's some data I've gathered in my search to understand the basic refrigerants. I'll update this when/if I learn more.

chemical composition
R134a: C2F4H2. (CF3CH2F)
R12: CCI2F2
I could not find the composition of envirosafe or of Z134.

Auto-ignition temperature
of envirosafe: 1,246* F.
of propane: 920-1020* F.
of R134a: 1418* F.
ZeroR Z134: ?

Boiling point:
envirosafe: -36.1* F
Propane: -44*F
R134a: -14.9*F
ZeroR Z134: ?

Found this. Do we have any chemistry whizzes in here?


I found safety data that makes me think H280 is propane, H220 is Natural gas, but I'm not sure I'm reading them right. The "Dipentene" is probably the "odor added" that gives someone a clue that this potentially dangerous gas is leaking. The difference in auto-ignition temperature is enough to be worrying in using propane directly.