That is what I thought and have been told that by 2 different dealers. I asked a Heartland rep the question of what temp does the system change from heat pump to furnace, and I quote his answer, "They are not connected so they do not work in conjunction with each other. Each are seperate. Per engineering." So, do they switch from one to the other or not. I hear they do, and a Heartland rep says they don't. Still don't have an answer as to what temp the heat pump stops, but according to reps answer, I assume it works at any temp until I turn it off? Have they changed so they don't switch?