1997 Mazda B2300 heating/air

I have a problem with the heating air conditioning system. The air conditioning only works on max but it produces very cold air. Any other setting on the dial produces hot air ( air, vent, feet/vent, feet, defrost). Also the temperature control does not adjust. The air is always very hot unless on max air conditioning. Since I can not adjust the temperature, I am constantly turning it on or off to adjust my comfort level.