You can make 8 quarts of yogurt all at once in the Excalibur dehydrator. You use glass canning jars to hold the yogurt and put lids on the cans to keep the temperature even.
First "make yogurt" with water to test the right temperature. I found that on my model I need to raise the temperature by 10 F in order to get the right temp. So I set it 10F more than the instructions.
Comments by Marilyn Alm, author of the forthcoming cookbook, "Louisiana SCD Lagniappe", regarding the Excalibur dehydrator:
I also have two Excalibur 9 tray dehydrators (the 2900 model). I highly recommend this for yogurt making because you can use them for so many other things besides. Making macaroons, making beef snacking sticks, crisping crackers and bread sticks, making jerky, drying fruits and vegetables.... In point of fact, the reason I have two is because it developed that I always had something else in the dehydrator when I was ready to make yogurt! You can set the temperature on this, and it's very easy, as well as allowing you to make around 8 liters of yogurt at a time.
When using my Excalibur, I set the temperature to 105, so that if, for some reason, the temp varies a degree or two on either side, the fermenting temperature is still in the proper range.