Firebox floor of a furnace for combusting wood

A furnace for combusting wood comprising:

• a base arranged for resting on a support surface;
• a housing supported on the base and defining a primary burn chamber arranged for containing the wood to generate a combustible gas therefrom;
• a body of refractory material carried at a bottom of the primary burn chamber and defining an upper support surface arranged for supporting the wood thereabove that defines a floor of the primary burn chamber;
• a secondary burn chamber in communication with the primary burn chamber for receiving the combustible gas generated in the primary burn chamber and arranged for combusting the combustible gas to generate exhaust gas which is substantially free of incompletely combusted products of combustion;
• a heat exchanger supported in the housing outside the primary and secondary burn chambers and in communication with the secondary burn chamber to receive the exhaust gas therefrom, the heat exchanger being configured for transferring heat from the exhaust gas to a heating medium which acts to subsequently distribute the heat;
• a flue in communication with the heat exchanger and arranged for releasing the exhaust gas with the heat removed therefrom to an ambient environment of the furnace;
• and
• a fan operatively carried by the housing at a downstream location from the secondary burn chamber and arranged to generate an airflow to draw gas from the primary burn chamber and to the flue so as to define a flow of gas through the furnace;
• wherein the body of refractory material is thermally conductive;
• and
• wherein the secondary burn chamber comprises a combustion duct which is defined in the body of thermally conductive refractory material below the upper support surface and arranged to convey the combustible gas and to support combustion thereof upon conveyance through the combustion duct before release to the heat exchanger.