Incubation and Hatching effect of humidity Glenda L Heywood Here some facts on hatching and humidity as told to me by a friend. The hatcher and Incubators setting in a house is in a low humidity area. Your air conditioner pulls the moisture out of your house and that makes the house have a lower humidity. If you take your Incubator to a bath room you will have a higher humidity than say in the bed room. But your AC is designed to remove humidity from your house. Your heater will also remove humidity from your house. That is why lots of people put in line humidifiers in the HVAC units. If you put that Incubator/hatcher in a garage it will have more humidity due to the cooling and warming of the room. You temp will fluctuate more because of the change in temp and humidity. In an unheated room you will have fluctuation in temps more that in a stabilized room. The Incubator gets its fresh air from its surrounding so if it takes in cold air the Incubator temp will fluctuate some and the humidity will do the same. I'm just not sold on the idea that the temperature and moisture in a room doesn't affect the moisture and temp in the Incubator. Also the barometric pressure will have some to do with the temperature fluctuating especially if you use the wafer control, but it doesn't seem to bother the electronic control because they don't work on a opening and closing of a wafer.