The systems designed for 134a just use a bigger compressor and sometimes a bigger condensor and operate at a little bit higher pressure. Anything can be used as refrigerant with the right design. Some are just more efficient than others. You could make a system work on water if you designed it right...
There is a lot of underlying junk involved with A/C and I wish I understood what the government is trying to do. 134 will burn and is poison, but it's mandated for all new cars. Why? We have dozens of R-12 replacements that are EPA approved. Why don't local A/C shops sell them? If shop A offers to retrofit you for $300-$800 and shop B will vacuum you and charge you up with a new blend for $80, where will your business go?
And if R-12 is so harmful, why can we still buy it? I mean, where does everyone think that it's going? Even if your car has no leaks and the R-12 is recovered before the car becomes scrap metal, eventually all of the R-12 in the U.S. will end up leaking into the atmosphere. If this was not true, there would never be a shortage and the price would not continually go up because we would actually be getting a surplus as more and more R-12 cars hit the junkyard making more and more freon available.
What a deal. I can pay a shop to take my valuable R-12 from me ("recover"), then pay them to work on the system and finally pay them $50/lb.(x2.5lbs=$150) for more of the same substance that will only stay in the vehicle for 1-3 years. Whatever happened to grandfather clauses? This was not my design, it's the way GM made my vehicle, why is it now impossible to maintain it?
What will we do if the EPA ever bans gasoline and we all have to pay for propane conversions?
<font color=green>If a K-5 is "Built not Bought", why does this stuff cost me so much money?
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