Draft air control system

Abstract From the Canadian patent

A draft air control system for fireplaces comprising a duct having an outside end in fluid communication with outside air and inside end terminating at a location below the fireplace grate, damper means adjustably controlling the cross-sectional area of the duct, hood means covering the inside terminal end The hood means comprises a throat section passageway in fluid communication with the duct, a second passageway directing airflow in a generally lateral direction and including a downwardly opening outlet to permit essentially unrestricted airflow from the duct into the fireplace beneath the grate and essentially preventing passage of particulate matter into the duct.