Allows for a 4" outside air vent to be connected to a 3" Outside Air Adapter, both sold separately. For use with the below units

Hearthstone Castleton with 90-53300 adapter
Hearthstone Heritage with 90-53220 adapter
Hearthstone Mansfield with 90-53220 adapter
Hearthstone Equinox with 93-53500 adapter
Hearthstone Bennington with 93-53500 adapter
Hearthstone Manchester with 93-53500 adapter
Hearthstone Green Mountain with 96-53400 adapter
Hearthstone Shelburne with 96-53400 adapter
Hearthstone Craftsbury with 96-53400 adapter
Ambiance Hipster with 96-53400 adapter

When considering placement of the duct on the inside and outside of the house, keep in mind the need to avoid wiring and structural members of the house. Locate the termination of the duct on the outside wall in such a manner as to preclude the possibility of obstruction by snow, leaves, or other materials. Screen the outside termination with a ¼” x ¼” mesh rodent screen, and cover it with a rain/wind proof hood. Periodically check the screen to ensure it is not blocked by debris such as spider webs or leaves

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3" to 4" Outside Air Increaser

Product Description

Allows for a 4" outside air vent to be connected to a 3" Outside Air Adapter, both sold separately. For use with the below units

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Write a Review

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