Is R-22 Freon compatible with R-12 Freon?

No! Answer No, it will run at a much higher pressure and will probably blow your safety valve. Of course, the answer to your question regarding compatibility could be taken another way.

There are mixtures on the market for automobiles with r-22 in them. Chemically it's not a problem, but the pressures are so much higher that to REPLACE r-12 with r-22 would be guaranteeing a system failure. Mixtures for cars with r-22 in them also have other (much lower pressure) components to help control the high pressure of the r-22.In fact, despite the inherent problems with MVAC (leaks and fractionization), mixtures of refrigerants offer more efficient utilization of the condenser and evaporator surface area.

Each refrigerant has it's own 'sweet spot' pressure / temperature for condensation and vaporization If you are running a mixture of refrigerants, each will find it's own sweet spot in the condenser and evaporator, allowing for a number of sweet spots for each refrigerant. When you run one refrigerant, you will get basically one sweet spot per heat exchanger.

I cant really gove you an answer,but what I can give you is a way to a solution, that is you have to find the anglde that you relate to or peaks your interest. A good paper is one that people get drawn into because it reaches them ln some way.As for me WW11 to me, I think of the holocaust and the effect it had on the survivors, their families and those who stood by and did nothing until it was too late.