I hope this thread gets some action, because I am trying to figure this out too. All my racks are back heat. Wish they were belly heat, but I didnt know that when I bought them. I just cranked them all up, and I think it is good. I have my thermostats set at 98 dg for the large racks and 95 for the smaller. I have been here for about a week or so and everybody seems happy.