E28 Defroster Vent Blows Heat All-The-Time

[Mark Rich <mrich22@xxxxxxxxxxxxxxxx>]

Is there a way to stop the continuous flow of heat from the defroster
vents in my '84?  It's just like the VW I used to have, year-round
heat.  It looks cheesy when you have to stuff a rag in the vents to
prevent the warm air from smacking you in the face.  It also causes my
A/C to work twice as hard to cool the car.  Any wisdom would be greatly
appreciated.

Thanks in advance,
Arizona heat in my 528e

------------------------------