I have been looking in the manuals for the amount of freon it takes for the engine chasis air condition on a 92 Breakaway 30' with a Cummins.Czn anybody give me a idea? Has anybody changed them over to 134 freon?

I recently serviced my A/C system and put only 2 lbs of R-12 in after evacuation. Was very surprised how little it took. I wil know next week how well it works on our trip to Houston. Didn't consider changing to R-134 although I am sure that Acme has conversions available for this system

HTH

I changed over to r-134 in my sob 34ft with a cummins. The data plate on your compressor will give you an amount of freon and it should be roughly the same for 134. I'm $ure opinion$ will vary on how in depth you $hould go with the changover, whether to change every $eal in the $y$tem, drain all oil out of the $y$tem, $ome may even $ugge$t replacing the compre$$or. At a minimum, though, you should consider changing out the dryer/filter and replacing any seals that you suspect could be leaking. Automotive parts stores will also have the changeover kits if you do it yourself.

I converted both my van and SOB to R-134a, with no problems. Both also had the compressors replaced, but that was unrelated to the refrigerant.

It's best to flush the system and use the contemporary PAG lubricant.

BTW, usually a bit LESS R-134a than R-12 is appropriate.