Phoenix heat in summer w/Class A coach

It can be done! When were in Lake Havasu, AZ. in early October it's around 103* we have a Winnebago with 2 AC's and were at 83* inside the coach. It's very hard to properly cool in Arizona due to there's very little humidity and AC units work off of humidity. Lake Havasu is about 1,500 lower in elevation than Phoenix and on most 100* day's the humidity is around 8. What we found to work best for us is if possible park under a shade tree, get a chrome reflector type windshield sunshade, and start cooling your coach down in the early in the AM as possible. Also, if you don't have them get a shade protector for your tires (wheel cover for your tires), that hot sun and the UV Rays will cause ozone cracks in older tires. I tried cooling my coach down with water my first time in AZ. and what a mistake that was! The water is so hard it left large water spots all over the coach. It made the windows hard to see out of. And if you wash your coach or car do it in the shade and wipe the water off as quickly as possibly, never wash in AZ. out in the sun. And for drinking water we never drink anything in Arizona but, RO Water (reverse osmosis). The PH in AZ. is about 6.5 (very hard water) where in Washington State most places it's 8.5. We also go to laundry mats that feature soft water to wash our clothes in! All of this info is just IMHO, thru experiences the wife and I have been thru in AZ. (3 years in AZ.). Good Luck and Happy trails! I'll be down there in AZ. for 6-7 months in October.