Air Conditioner question

j-d wrote:
Doc, Your conclusions are correct. Some room A/C window units have a little passage that can be opened to bring in some outside air. We had an old Coleman Mach RV A/C that I thought had something like that, but it's been a long time so don't hold me to it. Our newer Mach does NOT.

BTW, that diagram is what you need to understand to periodically clean your Roof A/C. It's pictured without the plastic shroud. The angled shrouding over the Blue Part (evaporator) has to come off in order to clean the blue coil, and the drain pan and drain outlets directly under the blue coil. The red coil (condenser) may trap a few leaves but that's usually it. Notice, the air blows through from the front side of that coil.

What the OLD Colemans had was a lever on the inside shroud that caused a damper door inside the metal plenum to open and close to direct more air out the REAR than the FRONT. But not to allow outside air IN. The only units I saw with the Delta's were the original Winne Elandan and Itasca Windcruiser from the mid 80's. Doug

I know this is way off topic, butttt, 1968 Yamaha DT-1 enduro...It was my second motorcycle, I was 16..I was working in my Dads machine shop for $2.25 per hour. (Pretty good at the time for a kid). Paid $750 for the bike. My Dad cosigned a $250 loan from the dealer. Ran the wheels off that bike in the woods and on the road.
Again sorry for the off topic/forum comment but I just couldn't resist. Thanks Chum Lee for bringing that great memory back..

dougrainer wrote:
ALL RV ROOF MOUNT AC UNITS RECIRC THE AIR. THERE HAS NEVER BEEN A RV AC UNIT THAT PULLS IN OUTSIDE AIR AND NEVER WAS AN OPTION TO DO THAT. Of course, I have only worked on RV AC's for 39 years. Doug

I have seen them. but it may have been more than 39 years ago. Let .. No.. I've seen them since then but the A/C's were already years old when I saw 'em. As i said. they don't make 'em that way any more. any more is... Well Sometime last century... The ones I've seen (and this applies to Window A/Cs for houses as well) date back to the 80's at least for home units. likely before that for RV's.

WHY did they stop making them that way? Efficiency THere was a mandate, came out in the 70's as i recall to make things use less energy. and they use less energy if they just recirculate. no exhaust or intake.