We just started “Winterizing”. I looked at the weather forcast all the way through October and it doesn’t look like we’ll get back to 80 degrees the rest of the way out sooo, the first thing I did,..Shut down the water to the Swamp Cooler and drian it. I want it to be completely dry before I cover it. (I cover the outside box and I also tape foam on the inside unit and cover that).
Here are more ways to Winterize from – http://www.popularmechanics.com/home/interior-projects/how-to/g52/winterize-home-tips-energy-461008/