Virgil,
If you can provide a separate feed for the auxiliary fan, wouldn't it be simpler to just use relays with a SPST (normally open) contact and parallel the contacts?
The coils would each be wired independently to the outlets as per your diagram, and either relay closing would energize the aux. fan from its own supply.
[This message has been edited by pauluk (edited 05-25-2002).]
