I have a 2013 Key Largo. I continue to be frustated with the inefficiency of the AC. Recently, after running it for 7 hours there was a 5 degree difference between inside and outside. A service representive from the dealer came to look at it, but wasn't able to see a problem. He was going to contact the factory, but months later we've heard nothing. We have dual air conditioners, but neither one seems to be running efficiently. This is frustrating and a problem we never experienced with any of our other RVs. Any thoughts?