Forced Air SystemThis system is by far the most common type of home heating and cooling system.
Distribution
Air heated in a furnaceAir distributed from furnace through ductwork and into room by registers
Fuel Sources
Furnaces may heat air using various fuel sources such as natural gas, propane, oil or electricity
Advantages
Only distribution method that can used for coolingAir may be filteredAir may be humidifiedAir may be dehumidifiedInexpensiveFurnace can attain highest AFUE
Disadvantages
Requires ductwork and takes space in wallsFurnace fan can often be heardMoving air can distribute allergensAir requires filtration and regular maintenance.