Decorative direct vent fireplace

Abstract

A direct vent fireplace unit that resembles an open hearth wood fireplace. The unit is installable in the interior of a dwelling above a surface defining an outer hearth. The unit includes an outer casing to define a cavity in the dwelling adjacent the outer hearth surface. A combustion chamber is provided having enclosing walls, a floor, a roof and an open front face with a combustion air inlet and an exhaust outlet communicating the combustion chamber with the exterior of the dwelling. The combustion chamber is mountable within the cavity of the outer casing such that the floor of the combustion chamber is substantially co-planar with the surface defining the outer hearth. A burner element for burning fuel within the combustion chamber is connectable to a fuel supply. A controller to control the burner element and a transparent cover mountable over the open front of the combustion chamber to seal the combustion chamber from the interior of the dwelling are also provided. The fireplace unit recreates an open, wood fire ambience with active flames and a large front face for viewing the flames. The unit also enjoys improved heating efficiency over a traditional open fireplace while preserving the preferred active flame appearance.

I claim:  
     
         1 . A direct vent fireplace unit installable in the interior of a dwelling above a surface defining an outer hearth comprising: 
 an outer casing to define a cavity in the dwelling adjacent the outer hearth surface;    a combustion chamber having enclosing walls, a floor, a roof and an open front face with a combustion air inlet and an exhaust outlet communicating the combustion chamber with the exterior of the dwelling, the combustion chamber being mountable within the cavity of the outer casing such that the floor of the combustion chamber is substantially co-planar with the surface defining the outer hearth;    a burner element for burning fuel within the combustion chamber connectable to a fuel supply;    a controller to control the burner element; and    a transparent cover mountable over the open front of the combustion chamber to seal the combustion chamber from the interior of the dwelling.    
     
     
         2 . A fireplace unit as claimed in  claim 1  in which the controller is positioned externally to the combustion chamber and the outer casing.  
     
     
         3 . A fireplace unit as claimed in  claim 1  in which the burner element is a gas burner and the fuel supply is gas.  
     
     
         4 . A fireplace unit as claimed in  claim 2  in which the controller comprises a control module that includes a valve to control flow of fuel from the fuel supply to the burner element.  
     
     
         5 . A fireplace unit as claimed in  claim 4  in which the control module is connected to the burner element by at least one flexible line to communicate the burner element with the valve and to carry control signals from the control module.  
     
     
         6 . A fireplace unit as claimed in  claim 1  in which the controller comprises a control module that is operable to ignite fuel and extinguish combustion at the burner element.  
     
     
         7 . A fireplace unit as claimed in  claim 1  in which the base of the combustion chamber defines an inner hearth surface that is co-extensive with the outer hearth surface.  
     
     
         8 . A fireplace unit as claimed in  claim 1  in which the controller is positioned below and in front of the combustion chamber.  
     
     
         9 . A fireplace unit as claimed in  claim 1  in which the transparent cover comprises an outer frame adapted to sealably engage the open front face of the combustion chamber with the outer frame retaining a transparent panel.  
     
     
         10 . A fireplace unit as claimed in  claim 9  in which the transparent panel is a ceramic glass panel.  
     
     
         11 . A fireplace unit as claimed in  claim 9  in which the transparent panel is a tempered glass panel.  
     
     
         12 . A fireplace unit as claimed in  claim 9  in which the outer frame defines a cover having a protruding front surface with angled sides.  
     
     
         13 . A fireplace unit as claimed in  claim 9  in which the outer frame defines a cover having a generally planar front surface.  
     
     
         14 . A fireplace unit as claimed in  claim 13  in which the outer frame includes an arcuate top edge and the open front face of the combustion chamber is shaped correspondingly.  
     
     
         15 . A fireplace unit as claimed in  claim 9  including a clamping system to releasably retain the outer frame over the open front of the combustion chamber.  
     
     
         16 . A fireplace unit as claimed in  claim 15  in which the clamping system comprises 
 at least one anchor point on the combustion chamber;  
 at least one latch member pivotally connected to the outer frame and movable between an engaged position of the at least one anchor point to interconnect the outer frame and the combustion chamber and a disengaged position of the at least one anchor point to permit removal of the transparent cover.  
 
     
     
         17 . A fireplace unit as claimed in  claim 16  including a pressure relief system to avoid excess pressure in the combustion chamber.  
     
     
         18 . A fireplace unit as claimed in  claim 17  in which the pressure relief system comprises a biasing member associated with the at least one anchor point to bias the anchor point to a position that sealably engages the outer frame to the open front of the combustion chamber by default when the latch member and the anchor point are in the engaged position and which allows movement of the outer frame away from the open front of the combustion chamber when excess pressure develops in the combustion chamber to relieve said excess pressure.  
     
     
         19 . A fireplace unit as claimed in  claim 18  in which the biasing member comprises a spring extending between a fixed stop surface mounted to the combustion chamber and a movable stop surface connected to the anchor point.  
     
     
         20 . A fireplace unit as claimed in  claim 17  including a joint formed between the front cover and the combustion chamber to allow pivoting of the front cover with respect to the combustion chamber to permit relief of excess pressure.  
     
     
         21 . A fireplace unit as claimed in  claim 16  in which co-operating anchor points and latch members are positioned at each side of the combustion chamber.  
     
     
         22 . A fireplace unit as claimed in  claim 16  in which the at least one anchor point is removably attached to the interior of the combustion chamber to protrude through a wall of the combustion chamber to the exterior of the combustion chamber.  
     
     
         23 . A fireplace unit as claimed in  claim 16  including a tool to releasably engage and pivot the latch member between the engaged and disengaged positions.  
     
     
         24 . A fireplace unit as claimed in  claim 9  in which the transparent surface occupies an area that is at least about 85% of the area of the open front face of the combustion chamber.  
     
     
         25 . A fireplace unit as claimed in  claim 9  in which the transparent surface extends across substantially the same area as an opening in a wall of the dwelling communicating the cavity defined by the outer casing with the interior of the dwelling.  
     
     
         26 . A fireplace unit as claimed in  claim 1  including a heat storage chamber associated with the outer casing.  
     
     
         27 . A fireplace unit as claimed in  claim 26  in which the heat storage chamber comprises an insulated region of the outer casing above the combustion chamber through which the exhaust outlet passes, exhaust gases in the exhaust outlet heating the insulated region by conduction.  
     
     
         28 . A fireplace unit as claimed in  claim 27  including a heat distribution system for transferring heat from the heat storage chamber to a remote location.  
     
     
         29 . A fireplace unit as claim in  claim 28  in which the heat distribution system comprises at least one port in the heat storage chamber, a passage from the at least one port to the remote location and a fan to transfer heated air from the heat storage chamber to the remote location through the passage.  
     
     
         30 . A direct vent fireplace installed in a cavity in a wall of a dwelling to have a viewable portion extending into the interior of the dwelling through an opening in the wall extending upwardly from a hearth surface comprising, in combination: 
 a combustion chamber having enclosing walls, a floor, a roof and an open front with a combustion air inlet and an exhaust outlet communicating the combustion chamber with the exterior of the dwelling, the open front of the combustion chamber extending across substantially the full opening in the wall;    a burner element for burning fuel within the combustion chamber connectable to a fuel supply;    a controller to control the burner element; and    a transparent cover mountable over the open front of the combustion chamber to seal the combustion chamber from the interior of the dwelling.    
     
     
         31 . A direct vent fireplace as claimed in  claim 30  in which the controller is positioned remote from the opening in the wall.  
     
     
         32 . A direct vent fireplace unit installable in a cavity within the interior of a dwelling that extends upwardly from a hearth surface, comprising: 
 a combustion chamber having enclosing walls, a floor, a roof and an open front face with a combustion air inlet and an exhaust outlet communicating the combustion chamber with the exterior of the dwelling, the combustion chamber being mountable within the cavity and the open front face being dimensioned to define a hearth opening that substantially fills the cavity;    a burner element for burning fuel within the combustion chamber connectable to a fuel supply;    a controller to control the burner element; and    a transparent cover mountable over the open front face of the combustion chamber to seal the combustion chamber from the interior of the dwelling.    
     
     
         33 . A direct vent fireplace unit as claimed in  claim 32  in which the controller is external to the cavity.