I haven't been able to figure out exactly what these little sliders are
supposed to do in my van, yet.  I'd guess, since they are blue in color they
have something to do with outside or fresh unheated air.  I am speaking of
the vent panels in the rear lower corners of the front doors in my normal
(non-AC non-Westie) 84.  They are about 10" long and 3" high, with a blue
sliding door/lever and a louvered grill.

  Open or closed, I can't detect any difference in air inside the vehicle.
The Vanagon heating and ventilation system, it's controls, it's basic
design, the way the heated coolant is routed and the valves that direct it
all around....it all seems a bit weird to me...It does work, somehow, when
all is well with the valves and cables and hoses, but you almost seem to
need an Ouiji Board to un-ravel how they were thinking when they built this
system.

  So what the heck to those slider's do?  I am guessing they may be an inlet
to take cabin heated air into the defrost?  Or perhaps something to do with
the vents on the dash corners?

  Anybody?
  Don Hanson