In this video, This Old House plumbing and heating contractor Richard Trethewey explains how to quiet a noisy forced-air system.
Steps for Quieting a Noisy Forced-Air System
- Mark the center of start collars on the return and supply side of the heating duct.
- Cut holes in sheet metal ducts using a drill fitted with a circle-cutting jig.
- Attach start collars to the duct with ¾-inch self-tapping sheet metal screws.
- Install bypass damper between the two start collars; fasten damper with sheet metal screws.
- Seal seams around start collars with foil tape.
- Adjust the counterbalance weight on the bypass damper arm.
- Turn on the furnace to ensure the bypass damper opens.