 So I have two zones. I have upstairs and downstairs. So I have two thermostats and two fan controls, and it actually has damper controls, so it turns off the upstairs when I want to. So what's cool with that is, is on a hot day, it could be 70 degrees downstairs. I don't need to have the AC on down there, but I need to have it upstairs, so it'll put everything upstairs. Now, with an older home, you are limited to what your existing ducts are that go up between the first and second floors. So in my house, it can only do so much.