RV's have AC's and furnaces, but very thin walls. That's why some RVParks may frown on leaving animals all day. But we've never stayed in a park like that.
In fact, we've left our two cats for a long weekend and longer without any problems. Most of the people in RV Parks that stay awhile are out working during the day.
RVParks may have power issues and so for periods of time, nothing is running. But with plenty of water cats do fine. We ran out of LP one Winter and our kitty had crawled under the covers to stay warm. The inside temps (which we monitor) were 40d when we opened the door.
