Air conditioners ... open windows to cool things down?

The real solution is to pull 50 amp power to the RV.

Otherwise the air just recirculates so the vent fan may concentrate cool air in one area but in the end is pulling heat in somewhere else. RVs are generally not well sealed. If you have a hot box from driving all day it may help to push some of the hottest air out. Soon you need to just close up and let it work.