Ford Repair: 1996 Ford Thunderbird heater, 1996 ford thunderbird, air conditioner compressor

Question
Erik:
I just replaced the heater core in my car because it was leaking. Now whenever the air conditioner compressor comes on, I get cold air, i.e. when I switch it from floor to defrost. The air flow changes as it should, I just get cold air. I can switch it back to the floor and I get hot air. Also, there is no difference in the heat temperature when I try to adjust it. I checked the wires on the back of the heat adjustment knob. They are connected and tight. What could be causing this problem?
Tom

Answer
Hello and thanks for the question...I'll try to help.
 Since you had to remove the evaporator case to replace the heater core, I would check to make sure that the wiring harness is hooked back up to the blend door control motor.......on top of the evap. case.
Hope this helps,
Erik