How Does a Duct System Work, and Why is it So Important?
The air distribution system in your home commonly called the “ducts” is used to heat and cool your home is a network of tubes that distribute the heated or cooled air to the different rooms in your home. This branching network of round or rectangular tubes—usually constructed of sheet metal, fiberglass board, or a flexible plastic-and-wire composite—is found within the walls of your home.
The duct system is designed to supply rooms with air that is “conditioned”—that is, heated or cooled by the heating, ventilation, and air conditioning (HVAC) equipment—and to circulate or return the same volume of air back to the HVAC equipment.
Usually, air-duct systems lose 25 to 40% of the heating or cooling energy put out by the cooling and heating system. Leaks are a very common reason why conditioned air is lost in the duct system, which makes the HVAC system work harder, thus increasing your energy bill. In addition, duct leakage can lessen comfort and endanger your health and safety.
Your duct system has two main air-transfer systems—supply and return. The supply side delivers the conditioned air to your home through individual room registers which what you feel blowing out of threw your heating vents. The return side withdraws inside air and delivers it to the air handler of your central system. All of the air drawn into the return duct(s) is conditioned and should be delivered back to the heating registers.