Mercedes Benz repair: 89 mercedes 300E A/C Heat not working, actual control, freon

Question
I replaced the actual control unit inside the car with a newer one. I hear the response when you press the buttons, but no air or heat comes through the vents when the car is on. I'm not sure but i dont think i have any freon in the car either. what could be causing this to happen?

Answer
Heater is Heat and comes from a heater core (which is a small radiator type system in the evaporator case. A/C is what the freon is for. The freon dissipates the heat. One is for one thing and not for the other. So Now tell me exactly what is the problem.
Does the fan blow any air (HOT or otherwise)?