If you have never purchased an AC unit for your home and are wondering if there is any science to whether or not any size unit will work the best, the answer is yes. If you want to ensure that you will get the best air circulation and have air flow throughout your whole home, than you need to get the proper unit. In this article we will discuss how to choose the best AC unit for your home so you can relax in comfort no matter where you may be resting.