If you are crazy, then so am I (as you can see by my signature). I also have Central Air, my sewing room is upstairs, and I put a window A/C in there because it's hotter than Hades in the summer. I do close the door so that I'm not killing my little window A/C trying to cool the entire upstairs ( and paying the local power company even MORE exhorbitant rates than they already charge us). You deserve to be comfortable, just sayin'....