Screw the Coleman AC. They are junk. Get a different brand name of AC and you will be fine.
I can get 50 degree air coming out of my AC on a 85 degree day. There is one member on the board that has a Dometic Penguin and he says his will do the same. But, I have no personal experience with them
I hear the Atwood AC's are good but, I do not have one.
I do have experience with the Coleman's because my brother had one. His was ****. Taking the cover off of the top to try and clean it I found it was just a terrible, terrible, design.