Thanks Paul,

That is how I will do it. Having the heat source outside the dehydrator itself will give me much more control over how much heat I allow to enter the unit. I'll put both fans on top, independently switched, so I have more control over air movement. Heat source(s), be it light bulbs or heater cones as suggested by Ed on the techniques board, will be independently switched also for more control over amount of heat.

Thanks for your input.

Ken

: Use them for exhausting the air if you use several bulbs and thus have a
: diffused heat source. If you have a concentrated heat source you want the
: air to be directed on that so you spread the heat around and don't get a
: hot spot.

: If you use the fans to exhaust the air in the box you can make a large air
: intake, complete with a large air filter to keep dust off the food. A
: slidign panel in front of this air intake allows you to regulate the
: amount of air that enters the box. With less air entering, the temperature
: will rise a bit more. More air will cool the heating elements, reducing
: the temperature in the box.

: Why not make an air intake on one side, say 15 inches long, by 4 inches high.
: Cover that with a filter. Inside the box, and directly in front of this
: intake place four 100-watt light bulbs and sockets. on the other side
: place a baffle so direect light does not heat the foods by radiant heat
: (overcooking those things that are nearest). The air coming in will flow
: past the bulbs and be heated before being drawn past the racks of food --
: which are not on top of the heating elements, but along side them.

: Just a thought

: PGJ