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Community and Q&A

Cold weather damper for island exhaust

Peter Whitman | Posted in Mechanicals on

I am looking for advice for a damper on the exhaust-side of my cooktop,island exhaust duct. The fan is 600 cfm and has a gravity damper just above the fan inside the hood meaning the 8″ duct between the damper and outside wall is filled with cold air leaking into the kitchen. I am looking into adding a second damper – probably mechanical that is wired to the hood motor, to open and close when the fan is switched on and off. My HRV guy told me to get a Broan MD8. Broan says no. Any help is appreciated. New home, Closed cell. Southern coastal Maine. HRV. Thanks!

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  1. John Clark | | #1

    You can buy exterior wall caps that have a damper (gravity).


  2. Expert Member
    Michael Maines | | #2

    Tamarack's Cape Backdraft Damper is a good, passive product for your situation: It must be installed in an accessible location for regular inspection.

  3. GBA Editor
  4. Peter Whitman | | #4

    Thanks again Martin!
    Please give my regards to Paul Biebel when you next see him.

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