Hi folks - It's been a while since I've Posted.

On my '92 Breakaway would the dash/chassis A/C unit be R12? And what about the original DuoTherm roof units?

Thanks.

I believe all the vehicle systems until the mid 90's were R12. The smaller RV and window types used something else I think. All R134 in vehicles now. There should be a charging label somewhere on the sytem.

It can be converted but not simple. R134 systems use higher pressures, with different lube oil. They used higher pressure hoses, since the R12 hoses tended to lose charge. The valves are different sizes so you have to know what you're doing to get it to work well.

I gave up on my engine AC. I just run the generator and the roof ACs. Works fine for me.

good luck!

I'm not sure I want to address anything you "gave up on".

After posting I found writings that all vehicles were forbidden using R12 starting model year '94.

The roof's old DuoTherms work fine. And their noise isn't nothing compared to the wife's ... and ... and

But if I could pick up some old stock refrigerant, I might be able to make it my kids' problem.

I understand they do have charging ports in the event they need boosted.

The R12 systems in our Barth's are old and did not have much capacity to begin with.

The engineers of the day said due to the smaller molecules in R134a one needs to make a bunch or revisions from R12. I think they are just living in a perfect world.

The oil does need to be changed for higher temperature use. The expansion valve may lose a tiny bit of effectiveness but will function. If the rubber hoses and fittings were holding R12 they will hold R134, they were designed with 150% minimum safety factor but even in your case they are 30 years old and probably already are leaking unless they were changed, so change them.

The compressor is old, probably won't last forever, but if it was working it will continue to work for at least a bit longer. You will have to play around with the R134a charge but the receiver's cut down on the required exactness.

Expect to lose a slight bit of cooling power but it probably never was very good anyway!

Steve and I agree the A/C chassis systems are problem prone and not very effective, I dumped mine too and will use the roof unit when necessary.

I have used the roof air going down the road and it does work well. However, my generator is propane (high operating cost) and I'm not wild about driving down the road with my propane's main valve open. Wish they had a G Force cut off on the propane tank (like many cars with electric fuel pumps).

I didn't know if the roof air was R 12 or 22. My coach is not accessible right now.

Started R12, then R134. R134 kept leaking slowly. I am now trying propane. Didn't work well but also ran out before I got it working. Been to hot here so it is on hold until winter comes. But the little I got in it appears to still be in there.

I have had good luck with propane in my 04 Chev pickup. Holds well and cools well. Cheap too.

My '92 Breakaway original DuoTherm roof AC is an R22 refrigerant unit.