I bought this when we rented a house that had a converted attic for the master bedroom. It got incredibly hot in there even if the weather outside was just 60 degrees. It was like a convection oven! We had moved into the house in January, so it just took a few months to warm up and become pretty unbearable. We just needed a small unit (and it was a tiny window, anyway) and this one fit the bill. It kept our room nice and cool. Now we are in a different house, but we still use this in the warm months just for the master bedroom. We've had it since, I believe, Spring of 2013. So we've used it for 3 years now, and we'll probably be putting it up in the window again soon. No problems and no complaints.