I've done a pretty good search on this subject

Right now there is no charge in the ac system. (I am refurbishing the components - both under hood and in dash board) Question: I have changed all the vacuum pods. The recirculation (large flap just behind glovebox) does not move - the old one had a leak - tested with mity vac. Does this flap function only when the ac is operable?
Note: The old one did work at one time.

Thanks Steve