I guess I should have said they are in my smallest room and there is a radiant heater that never turns off. Good point with the forced air killing the humidity. I think I could get around vibration with the connection of the heater to the rack being a floating joint of some sort. I was looking this http://www.lowes.com/pd_121116-1509-...t_avg_rating|1
and using some duct work to plumb it. But it would still kill the humidity most likely. But if it's only keeping it up to 80 it wont be running much if its only heating the rack i wouldn't think.