When my sister moved into her apartment, she was pleasantly surprised to find that there was a window air conditioner already sitting neatly in her bedroom window. I came up to help her unload the truck, and we were both thrilled at this added bonus.
Once we had brought everything inside, it was nice to get a blast of cool air from this free air conditioner. I was thrilled at how well it worked. It seemed like the previous inhabitant had just bought it and left it behind as a housewarming gift for my sister.
She continued to use the AC that she was given throughout the summer, and was continually happy with its performance. But, since the weather has been getting cold, she asked me if I would help her uninstall the appliance.
Since I already did this with my own air conditioner, I now considered myself an expert at removing window units from the window, and I happily agreed to help her. When I went though, we found out why the previous tenant left the unit behind: It was completely stuck in the window.
Rather than let her nice air conditioner get ruined after a winter exposed to the elements, I did some research and found out that it's possible to winterize a window unit. We purchased an outside air conditioner cover to protect the back of the AC from snow, rain and falling leaves, and then got some window insulation for the inside of the house.
We simply sealed the plastic window insulation over the window to close gaps from the outside, and found that that worked very well in terms of blocking out cold air. With my support, my sister now feels ready to face the winter.