<p>You can’t bring an air conditioner, it’s against fire code. If it has anything “going out” the window, they’ll see it and hunt you down. Seriously, you’ll be fine with a fan. It cools off by the end of September (so maybe 3 weeks maximum of slightly uncomfort) and doesn’t heat back up until the last week of april SOMETIMES. A friend of mine has been in a non-AC room all summer and they survived well enough, so you will do absolutely fine for three weeks.</p>