[tuga]

As some of you may know, I am a member of POG (Prevost Owners Group). It is a great organizaiton made up of 99% Prevost owners, 2 Newell owners, and a Blue Bird guy. Anyone who is interested in learning about Prevosts can join.

The subject of OTR air comes up often, and as you would imagine there are pros and cons discussed. The only real advantage I can see to an OTR system is redundancy; if your roof/basement ACs break down you have a back-up with OTR. In my 1987 Newell (3 roof ACs) and in my 1993 Newell (3 basement ACs) I have had 2 of the 3 break down at the same time! Guess what month they broke in; yep August, in Texas. I sure wish I would have had a OTR AC then. Keep in mind, that both of these Newells had crap for dash ACs. They never put out cold air - they didn't even put out cool air. I had Newell work on them and other AC shops try to repair them - the result was always the same - THEY DIDN'T WORK! Some time in 1996 or later Newell began using a really good dash AC. I have one in my coach (1999).

The dash AC in my 1999 works so good that I don't have to use the basement ACs until the temps get to 90 degrees. This dash AC is far superior to the old units. The subject of dash ACs brings me to my next point.

Marathon Coach around 1994 and later began converting Prevost shells with a different kind of OTR air. Instead of a 10 ton Carrier OTR AC (belt driven by the engine) they used 2 regular AC compressors like you would find on your car. Each compressor ran off of the engine and they cooled the inside of the coach nicely in average hot weather. So here you had the best of both worlds: a good back up to the basement/roof ACs and yet an inexpensive belt driven system run by the engine AC that could cool the entire coach without running the generator. RVers are cheap; they don't want to spend the money to run the generator. They want free AC using engine driven systems like OTR.

IMO this is the best set up I have ever seen for cooling a coach.

I would like to suggest to Karl to consider building a coach with the automotive compressors and evaporators - one in the dash area and the other in the middle of the coach to be used while driving down the highway. With Newells being insulated as well as they are I think 2 units would work. If not, put 3 units in; I'm sure the 650 hp engine could easily handle the little compressors. If you are going to have redundancy, the ACs are the place to have it. Nothing can ruin your day faster than driving a hot motorcoach!

Just my .02