Originally Posted by Air&Road

Sigh..... Well, it looks as if you are going to make me write this for about the hundredth time:

ALL alternative refrigerants such as Freeze 12 OR Freeze 12a fall into one of two categories; flammable or blend (Freeze 12 and 12a are blends.) The downside to a flammable does not need to be elaborated upon. A blend may need to be described.

Blends typically consist of two, but sometimes more than two refrigerants. Typically one of the components provides oil circulation and the other provides heat exchange.

The disadvantages of the blends are numerous, but the main two disadvantages are that the components leak at different rates, and they cannot be recovered for service.

Since the components leak at different rates, upon servicing a leak, the remaining refrigerant must be completely recovered, the leak repaired and then recharged from scratch with a fresh blend charge. This leads to the second disadvantage:

Since after a leak, the charge no longer has the correct blend, it cannot be recoverd and reused. It must be recovered into a scrap container and a DISPOSAL FEE MUST BE PAID.

Additionally every system using an alternative refrigerant, by Federal Law, is supposed to have the proper refrigerant specific fittings installed. I've done a good bit of auto a/c work and I have NEVER seen anyone install the correct fittings on a converted system except for 134a conversions.

The down sides to these alternative refrigerants are numerous and given that R12 has come back down in price to a level not too far above 134a, price, alternative refrigerants are clearly more trouble than they're worth in today's refrigerant market.