vintage kin has her original Duo-Therm rooftop air conditioning unit. It works just fine, it's quiet, and it blows cold air. We rarely use it as the majority of our camping is during milder weather or off the grid, but it was hot and sticky last weekend and we decided to fire it up. No problem cooling the trailer down, but after about an hour, condensation began blowing in from the interior vents. When I got home, I took the exterior cowling off and blew/vacuumed all the crud, flake rust, and dirt dobbbers from the floor of the drip pan. I ran the AC for another hour in the drive and it looked like all was well with a rivulet of water running down the side of the trailer like it was supposed to and the inside dry as a bone. However, when I shut it all down and moved the trailer to her parking spot I noticed the condensation dripping from the vents onto the floor. Parked, the trailer was not level, nosing lightly towards the tongue, which might have been the issue. The owners manual doesn't mention anything regarding normal draining, so I thought I would ask the group if there is a plugged weep hole/drain tube I might be missing, another maintenance suggestion (caulking, new weather stripping, etc.) or if the old gal is just plain worn out. I'm just not all that familiar with what I should be looking for on the original units and I hate to "upgrade" to a newer AC if the original is serviceable. Thanks.