Maxi-frig is probably propane. Some cars run on propane for fuel and carry far more than would fit in an AC system but nobody seems to duck into a bomb shelter when they drive past. Most cars have gasoline under high pressure under the hood and nobody ducks into a bomb shelter when they pass. But let someone mention installing propane in an AC system and people act like it is Chernobyl all over again.

I agree that I would rather have R-12 in my AC than propane or R134a.

Some refrigerants produce poison gas when they burn - call homeland security. Code Red.

Some people a thousand miles from home in hot weather and needing refrigerant in their AC, have been known to use the vacuum pump on the engine to pull the AC system down to vacuum and pump it up with propane; chill and enjoy the ride home.

Heads are reeling, blood pressure is rising, take a deep breath and read my sig line. Repeat as necessary.