We bought this AC for my daughters' room which has a 16 foot ceiling and a huge, drafty single pane church window. We've had it for 2 months now and it works really well at cooling the room. I insulated both hoses with spiral duct wrap, as I had heard that would help. And I had to jerry rig something to make the window panel work, as our window was way too wide for the setup it came with. Still, it was worth it, as it does a fantastic job of cooling the room. The room was 92 when I set it up, so I had it set to 80 at first and it cooled very quickly. over the course of a few hours I got it to the temp we wanted so I set it on 71 degrees and let it run. It shuts itself off when it reaches the correct temp and switches on automatically when the temp rises. My girls have been so much happier and can sleep soundly!