I tried searching to see if anyone had this problem, and I couldn't find anything. For most of the summer, I didn't use my AC. When I finally did, the first 3 settings didn't do much, they all blew the same, but the fourth setting blew like it is supposed to. I didn't care too much, since I don't use the AC much. But now I need the heat, and it is the same thing. The first 3 settings all blow the same, and the 4th blows hard. So it's pretty much all or nothing. Does anyone know of any reasons why this would happen? Thanks in advance.