Heater Box Design - Lame?

YY1 said

What does the temp slider do on the OP's car?

Been a while since I had an A, but all my B's have that slider control a valve.

Click to expand...

It opens and closes the door at the heater core. I think you can blend the hot air with cold to a desired temp. The other door is for floor/defrost or a blend of the two also. Real simple and cheap heater box.