Jerry makes a good point here about the R-12. On our Angola it worked great for 3 1/2 years, never any trouble, need of charging or anything. We began our research about A/C when we got the coach and got a quote of $8K for the conversion from Prevost Jacksonville and dropped the whole thing as being too many Lew Bucks for fixing something that wasn't broken.

Background: Prevost, as a matter of protocol, guarantees their work for a year. Their protocol also means (relative to changing to 134a) that they replace all hoses, fittings, the condenser sensor unit, synthetic oil, unloaders on the compressor, and so on. Yet, on the other hand, when the change over a seated coach for sale, they evacuate the system, change out the unloaders, put on a 134a charging adapter on the supply side of the compressor, fill it up with the new gas and send it out. So there are two different Prevost Service Center points of view, I guess, depending on who is paying the bill.

In the case of our crummy Liberty, it had, well, ah, self-evacuated due to the seal in the compressor being shot and a 1-inch rupture in the braided stainless line going from the compressor to the midships condensor unit. Replacing all that was going to be a job of removing the genset, water tanks, waste tank, etc. So we patched the line, which held nitrogen at 115 pounds for two days.

So our reason for converting to 134a was because we were indeed, 'there.' If your system is working well, you have enough to do before getting around to change over to 134a.

"If it ain't broken, lube it or chrome it."