HVAC question

[Ice&burban]

Ok, I've got a 90 Burb. I'm wondering if I need to replace the HVAC heater/ac controls. No matter what position I put the the control on (vent, heat, def, etc.) I always get heat out the dash vents. My ac has never worked (either compres or needs charged) but I'm worried about it, always cruise with widows down in summer. Also, if I put the control on cold I still get warm heat. Not as hot when it on warm, but still heat. I did purchase a new cable from LMC (it was a little long) and change it, but it's still warm heat coming out. Do you think I need to replace the entire control set up or could it be something else?