90 Quattro Backwards Recirculation System

["Dick Green" <dick.green@valley.net>]

Hi folks, long time no see.

I have a 1993 Audi 90 Quattro. Last year our not-so-local Audi dealer
replaced the A/C condenser due to a slow chronic freon loss. After that, the
front, rear, and side windows fog up horribly on the inside when the outside
temp is below say, 40F. Additional clue: I've been hearing a whistling
(rushing air) sound coming from under the right side of the dashboard ever
since the condenser was replaced, except when the air recirculation function
is enabled.

My theory is that the air recirculation function is operating backwards. I
believe that normally the car takes in fresh air from the windshield vents
via the fan located under the right side of the dash. When the recirculate
button is pushed, a door (or flap) opens to allow air from the passenger
compartment to mix with the fresh air before being circulated back through
the outlet vents. Trouble is, that door opens up almost immediately after
the car is started and stays open. If the A/C condenser is on, I can push
the recirculate button on and the door closes. I think this is backwards --
shouldn't the door open to recirculate? When the condenser is off, the door
is open and I cannot close it (recirculate is disabled, which is normal
according to the manual.) This is the situation where the fogging is the
worst.

A friend has a theory that either the door or the crank that operates it was
installed backwards when the dealer replaced the condenser. This seems
pretty plausible to me, and I don't see how it could be electrical (the plug
going to the solenoid is keyed so you can't plug it in backwards. This could
possibly explain the rushing air sound, too (i.e., something is incorrectly
oriented in the air stream.)

----> Can anyone out there confirm the theory or explain what's happening?
----> Can anyone out there explain to me how the system is supposed to work?
----> Assuming I can fix the problem, can anyone describe the procedure (I
know how to remove the glove box, but that's as far as I've gone.

Any help would be *much* appreciated. Please reply directly to ny email
address (dick.green@valley.net), as I won't be subscribed to the reflector
for very long.

Thanks,
Dick Green