Abstract: An unvented fuel burning appliance that includes a firebox, a burner and a front door releasably securable to the firebox. The firebox has an open front and enclosed bottom, rear, side and top surfaces. The door has a central panel with a catalytic converter positioned on the upper portion of the central panel. Exhaust gases from the burner are directed through the catalytic converter prior to exiting the firebox such that the catalytic converter eliminates or reduces harmful or noxious gases and particulate material contained within the exhaust gases. Heat that is generated by the operation of the catalytic converter is substantially directed, by way of radiation and convection, outwardly through the front of the appliance to reduce heat generated and maintained at the top of the firebox and thereby reduce the heating of the top surface of the appliance.