Manual A/C only at floor (89 boxie)

My HVAC only discharges at floor. Buick wagon sat idle for 8 months and now doors controlling flow do not move when control slide is moved. Took out radio and controls and found no kinked hoses nor audible vacuum leaks. No leaks under hood either. A/C blows cold on my feet and controls change from max econ bilevel vent heat def with different temps for each but all air discharge is to floor.
What should I do to fix?

Hey John,
I had a similar problem with my '87 box wagon (Chevy). Mine would only blow to the floor and simultaneously to the windshield. In my case it was indeed a vacuum leak. If you're certain you have no leaks, perhaps the louvers controlling air flow are simply stuck...perhaps due to built up dirt...? Another thing that comes to mind is if something is wrong with the selector switch itself...?
Good luck.
Matt

I had an 85 Caprice Wagon, and an '86 Buick Estate Wagon. This goes back a number of years, so it may not be precisely accurate, but the Buick did not have a vacuum operated HVAC system. It was operated by a number of electric motors, and position sensors. To be honest about it, it's a difficult system to repair. Newer systems are self-diagnostic, but this one is not. I had to go to a dealer and purchase a number of pages from the dealers manual in order to trouble-shoot it. I found a number of issues, and ended up going to a junkyard, and purchasing the entire under-dash system, and the  on-dash controller. As I recall, I ended up replacing two motors and three sensors, and that "fixed"it for the remainder of the vehicle's life.
My only suggestion would be to try and find the door that deflects the air from the floor to the vents, and possibly the defroster, and replace that motor and sensor with another.

Texas Mike has had some experience with that type of system. You just have to look into your rearview mirror,and say his name three times WITHOUT BLINKING,and he will respond.

Took radio out and pulled HVAC controls out as far as I could. On the manual system there is a rotary valve that directs vacuum to the appropriate motor to change damper positions. Mine is splitting so I need to find a new one...

Yep, you most-likely need a new ported-selector switch.  

If yours is the manual climate control, Google: Four Seasons 36694 Vacuum Mode Selector Switch



BUT before you do anything else, check the vacuum reservoir ball under the hood.   It's black, and if the hose to it is cracked, or the ball itself is leaking (they tend to leak/crack near the male fitting), that will kill your vent vacuum.



Good Luck!

-Mike