Gas

A naturally vented firebox is a fireplace that uses a single (double walled) vertical vent or chimney to remove combustion byproducts from the home. Unlike direct vent fireboxes, which use a sealed system to draw air from outside and expel gases outside, naturalyl vented fireboxes rely on the natural draft created by the chimney or vent to exhaust gases. Although they do utilize some of the room air, they typically have a fresh air vent drawing additional combustion air from outside. These fireplaces can also be used to burn wood.