Fireplace construction with adaptable combustion air inlet

A free-standing fireplace assembly having plural operating modes, selection of one of the operating modes permitting the source of combustion air and the rate of delivery to a fire to be controlled in accordance with the structure in which the fireplace assembly is installed, said fireplace assembly comprising:

• a housing having a firebox with an open side and a combustion gas outlet adapted to be in fluid communication with a flue;
• a transparent door for substantially sealing said open side;
• a base structure for supporting said housing above a supporting surface including an upright wall member between said housing and the supporting surface;
• a combustion air inlet in said housing near the bottom of said housing through which combustion air may enter said firebox;
• duct means having an upstream end positioned within and at a distance above the bottom of said base structure for opening to the interior of said base structure and a downstream end positioned adjacent the bottom of said housing and communicating with said combustion air inlet;
• an optionally usable intake conduit having one end removably connected to the upstream end of said duct means and its other end communicating exteriorly of the structure interior to provide fluid communication for delivery of combustion air from an external source to said duct means;
• means in said base structure providing communication between the structure interior and the interior of said base structure whereby combustion air is delivered into the upstream end of said duct means from the structure interior for delivery to said combustion air inlet when the intake conduit is disconnected from said duct means;
• and a movable damper mounted in said duct means intermediate the upstream and downstream ends thereof to be in the combustion air flow path regardless of which source of air is utilized and positionable to control the flow of combustion air from either source through said duct means including complete closure of said duct means to prevent air drafts.