Your home has hundreds of feet of air ducts running through the walls, floors and ceilings. This is the respiratory system of your house. These ducts remove stale air, filter it, deliver it to the heating and air conditioning unit and then distribute the supposedly clean heated or cooled air (depending on the season) back through the house.
The problem is, over time a lot of airborne contaminants get trapped in the ductwork. So that nice heated or cooled air you’re breathing might not be as clean as you think it is. Air duct cleaning is the process of removing the contaminants that have accumulated in the ductwork, so that you can go back to breathing nice clean air.