A vent-free gas insert turns your existing wood-burning fireplace into an attractive and efficient heat source. Vent-free fireplace inserts are classified as zone heating appliances. Zone heating is inherently more efficient than your existing wood-burning fireplace or your central furnace. A central furnace wastes 20 to 30 percent of the heat energy through ductwork losses and sends much of the remaining heat to unoccupied rooms. Don’t have an existing fireplace? These vent-free systems are also certified for zero-clearance installation in any wall. Just add one of our available surrounds to create an attractive in-wall fireplace.