How to Control Air Flow in Attic Ducts

Attic ducts direct forced air from the household heating and cooling system to different rooms on the main floor or upper floor, in buildings with more than one level. The ducts contain a damper attached to a louver that rotates to adjust air flow. Each damper is controlled separately by a metal rod that extends from the side of the duct. The damper may be located in the attic or at the point where the ductwork enters the attics. Look for the external adjustment rod.

Things You'll Need

• Stepladder
• Flat-blade screwdriver

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Instructions

1. • 1

     Unfold and place a stepladder below the ductwork if necessary to reach the adjustment rod.

   • 2

     Insert the tip of the screwdriver into the slot on the adjustment rod extending from the duct. Do not touch or adjust the wingnut on the rod.

   • 3

     Turn the slot in the rod so it is perpendicular to the ductwork in order to close the damper completely, stopping airflow in the attic ducts.

   • 4

     Rotate the slot in the rod so it is parallel with the duct to open the damper for maximum airflow through the attic ducts.