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woodman1's avatar
woodman1
Explorer
May 13, 2014

Did they change refridgerant type in newer A/C's ?

Ordering my new 5th wheel. Dealer recommended 3 a/c on a 39 ft model. They said in 2012 government made them use different freon and it doesn't cool like the older ones, according to Dometic. Anyone h...
Huntindog's avatar
Huntindog
Explorer
May 14, 2014
woodman1 wrote:
All I'm saying is what the dealer told me. That Dometic said with the newer freon, it doesn't cool as well. Just saying.

Here is the deal.
The newer refrigerents have a higher boiling point. A pot of water boils at 212. No matter how much more heat you apply to it, 212 is the max. The extra heat is carried off as steam or gas.
R22, R410,R12, and R134 work the same way. Except the boiling points in all of them are below freezing. In a refrigerant system the Freon is boiled off at a controlled rate, absorbing heat from the air as it does so. The compressor then compresses the Freon gas into a liquid that is hotter than the ouside temperture so that it can be cooled by it, and then the process repeats.

So any of the Freons are perfectly capable of maintaining a comfortable temp. The hardware components need to be sized correctly/differently due to the different boiling points, but since they are ALL below freezing, they will all work equally. In fact, the ACs are designed not to allow the outlet air temps to get to the freezing point, to avoid icing up, and restricting the airflow.

And yes some new Freons are coming. It seems that they have just discovered that 410 and 134 are bad for the environment....
I say follow the money.
Dupont held the patent on R12. When it ran out everyone was making it and the price dropped to .79 a can. Dupont lobbied congress about the problems with R12, and got it outlawed. The new 134 had a brand name of Suva and was said to be problem free. Guess who held that patent? Dupont.
I never looked at the 22 vs 410 situation, but I bet it is very similar

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