slowassintegra

so when i turn the knob that adjusts my temperature the car gets extremely hot even with the slightest move. When i try to move it back to cold it stays hot. Only way to get rid of the heat is to turn on the a/c. Usually after a day or two the system "resets" and cold air comes out of the vents again. This is beginning to really annoy me. Oh its a 90 GS.
Thanks