Why don't you just turn off the fresh air at the air control levers?
Seems to be quite effective for me.
(Ok, maybe a little gets through).

Mike G.

Stan Wilder wrote:

> Close the Vanagon fresh air vent.
> You can use just about any kind of tape.
> Very simple.......... take a look.
> http://williamwareagency.com/forsale/stanvan/closevent.jpg
> Stan Wilder
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