Unvented heating appliance having system for reducing undesirable combustion products

An unvented heating appliance located at least in part in a room and comprising:

• a firebox having an inlet receiving room air and an outlet in communication with the room for exhausting combustion gases into the room;
• a gas burner disposed within said firebox, said gas burner providing a primary flame and heat source, heating room air drawn into said firebox, and producing products of combustion;
• a heat exchanger having an inlet, an outlet, and a plenum defining a heat exchanger airstream circuit between said heat exchanger inlet and outlet, said heat exchanger inlet located below and spaced from said heat exchanger outlet and receiving room air into said plenum, said heat exchanger outlet exhausting heated air from said heat exchanger plenum into the room, said heat exchanger partially surrounding said firebox, said firebox outlet in communication with said heat exchanger outlet, a draft resulting from said firebox being under higher pressure than said heat exchanger, said draft aspirating said products of combustion from said firebox to said heat exchanger, whereby room air is drawn through said heat exchanger airstream circuit and exhaust gases from said firebox outlet are drawn into the room air stream;
• and
• a carbon monoxide catalyst element disposed in said firebox outlet, said carbon monoxide catalyst element oxidizing carbon monoxide contained within said products of combustion into carbon dioxide, and preventing airborne particulates from exiting said firebox.

A carbon monoxide catalyst element for oxidizing carbon monoxide into carbon dioxide and for use in heating appliances, said catalyst element comprising:

• a plurality of planar foils manufactured from stainless steel;
• a plurality of corrugated foils manufactured from stainless steel, said corrugated foils alternatingly interposed between said planar foils;
• a ceramic oxide coating disposed on said plurality of planar foils and said plurality of corrugated foils;
• and
• a precious metal coating disposed on said plurality of planar foils and said plurality of corrugated foils.

A gas-fueled stove, comprising:

• a firebox having an outlet in communication with ambient air adjacent said stove;
• a gas burner disposed within said firebox, said gas burner providing a primary flame and heat source, and producing products of combustion, said products of combustion exiting said firebox through said outlet;
• a heat exchanger partially surrounding said firebox, said heat exchanger drawing ambient air in through an entrance provided below said firebox, and exhausting convection heated air through an exit provided above said firebox;
• a combustion gas circuit including an inlet communicating air to said firebox and an outlet communicating products of combustion out of said firebox;
• and
• a carbon monoxide catalyst element disposed within said combustion gas outlet, said carbon monoxide catalyst element oxidizing carbon monoxide contained within said products of combustion into carbon dioxide, and preventing airborne particulates from exiting said stove.