Secondary Damper for Kitchen Exhaust Vent
In a PGH /green and reasonably tight house, should kitchen exhaust have a secondary damper the same way bath exhaust does or is the damper that comes with the hood sufficient?
If a secondary damper is needed for kitchen hoods, will the Panasonic EZ vent work? The Panasonic EZ vent has been reviewed on this site as an exterior termination with a reasonably good secondary damper for bath exhaust. However it is plastic and only comes in 4″.
1. Can the secondary damper and termination for a kitchen exhaust be plastic?
2. Can the Panasonic EZ vent be used to exhaust a 300 cfm 6″ kitchen exhaust (by adding a 6″ to 4″ reducer before the connection to the EZ vent)?
3. If the EZ vent wont work, is there a suggested secondary damper termination combo that could be installed within the soffit area?
The kitchen exhaust hood has a single (flimsy) rectangular damper at the top of the hood. The rectangular duct transitions up to 6″ round hard vertical duct. The 6″ round metal duct takes a 90 above the ceiling and runs about 7′ to the exterior soffit, where it connects to semi rigid flexible metal duct for about 2′, in which it turns down to exhaust out the soffit through a plastic grate with no damper. There is no option to re-route the duct to terminate the exhaust on a wall or the roof.
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