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Direct duct range hood

moose_head27 | Posted in General Questions on

Hi, just curious to know what the problem could be here with a range hood. The range hood is directed duct to the exterior of the home through a wall. The hood is a stand-alone unit.

The unit is is a Broan CM130WWN. When on, the unit recirculates into the interior of the unit. I checked the backflow damper on the exterior and it opens when on as well. I’d prefer the unit to vent directly outside, with no re-circulation. Any idea on why it’s blowing inside as well?

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  1. Expert Member
    BILL WICHERS | | #1

    The convertible range hoods usually have a baffle that changes the airflow. With the Baffle installed, you’re setup for outdoor venting, not installed is for recirculation more. In my expierience with the broan range hoods, if you have the baffle out but also have the exterior vent cutout open, you end up with a sort of mixed airflow mode with some air going outside and some inside.

    I’d check that the baffle is installed correctly. My guess is it’s not, and that’s why you have air coming out of the unit inside. There’s also a chance you have some kind of obstruction in the outdoor vent duct, but I’d check the baffle I mentioned first.

    Note that broan has manuals for their units available online if you need them.


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