What Zones Do - Zones are basically little junction boxes that can either open or close sections of the ducting. These zones allow the user to direct what rooms the air conditioner can blow into. Most air conditioners can only run about half the home at any one time, and zones allow you to choose which rooms to have on and which ones to have off. central air conditioning cost The main advantage of zones is that they give your cooling system flexibility. Zones allow you to choose which rooms you want to heat/cool and allows you to turn off rooms that you don’t want to be serviced.