I just bought a '92 190E 2.3. I love it but I don't think the climate control system is working right. If I press the "O" button the air system turns off as it should. But if I press any other button the following happens. Hot air comes out of the defrost vents, hot air comes out of the two vents on the sides of the dash, COLD air comes out of the middle vents on the dash, and at no time does air come out of the floor vents. I'm thinking two things; electrical, or some physical blockage-what-have-you.
Here's to hoping some one has had the same problem and knows the magic wand solution.