I have a 37'7" 3-slide class A. I summer in Eastern lower MI winter in SC. it came with a pair of 13,500 BTU Carrier Air V's which I can not replace. so when they went Compressors Up,. (or down) I replaced with 15,000 btu units... Still not enough in Michigan in August gets into the 90's indoors.
More than enough when it's only 40 out