I installed fans in my still air incubators. I think the because of the air being circulated, the temperature stays more even throughout the incubator. There is only 2 ways to hook up the fan. If you don't have the wires right the fan will blow in reverse and all you need to do is reverse the wires so the fan blows in the right direction. I have my fans blowing up towards the top of the lid of the incubator so the air isn't blowing down on the eggs. If the fan blows down on the eggs, when they start to hatch the air blowing on them can cause the membranes in the eggs to dry out and the chicks to stick in the shells. I took some tubing and made some spacers so there is air space between the top and the fan. This is my still air Hova-Bator I installed a fan in. I wired this one to my heating element. This had wire nuts I cut off and put new ones on. This is my LG I installed a fan in. I put a separate adapter on it. With this incubator I would have to cut the wires and lengthen them, so I put an adapter on instead.