[twindman]

I have had a 2006 and a 2013. I added an A/C to the front on both units. You definitely need a 2nd A/C. The only drawback is the dump units in the front don't really help a lot with the rear of the trailer. I have used a fan to try to push it to the back, but then the hall gets quite cool and guess where the thermostat is located! So I have to pay attention to temps otherwise the thermostat shuts off the rear unit!!!
My units neither were capable to use the ducts. Wish I could have done that.
By the way, when in the middle of Nebraska in the summer and temps around 100-105 we stopped at a park in the middle of nowhere. Hooked up and apparently they had a problem and blew our some electronic appliances and I think the A/C. Immediately bought a surge protector and it has saved my 2 or 3 times at parks. One park in N Idaho was mostly filled with Canadians! They only had 2 or 3 open temporary sites, so I got one. Each afternoon the voltage would drop to around 102 or so. The surge guard shut us down every afternoon, and would restart again in 3 minutes. I finally turned off the A/C until the temps dropped. A neighbor said his son stayed there the days prior, and said the same thing happened to him.

Just a FYI.