I crawled under the dash of my other vehicles... ( both of whom the AC is COLD... and have NEVER "rained" on me. Both driven in areas where the humidity and temps were high.
What I noticed was a LOT of insulation around the duct area, and firewall. Protection for the passengers from heat, engine noise of course, but also it does not allow much of the air in the cabin to come in contact with the ductwork.
Also, much smaller cabin area as compared to that of our Georgetown 360. I'm going to visit a local AC shop, who installs aftermarket units in old cars, and ask them what they use for insulation... or see IF they do.
My goal is to improve the cold air output, and stop the condensation.
Of course, running the RV roof air when I drive should also reduce the humidity, (or would it).... hmmm.
This brings in another point I have been meaning to ask.
ANYONE have an issue with ALL the water that drains from the roof, (when you run the roof AC), and it vents right over your side glass, mirrors and side cameras?
Got to be a way to fix / plug the "cuts" in the roof drip rails, and move them so the water exits in a different spot.
My side cameras also "Fogged" on that last trip! Bad seals... constant water dripping on them from the roof AC... Rain getting in them.... High humidity...
They are clear now, but of course, I'm back home in temperate weather, low humidity, and the RVs at the shop going over my "repair list!
Did I mention my windshield leaked too!! Leaked.... it looked like a water fall down the inside front glass, when I was driving! - LOL
(Dealer is going to reset the windshield)