| BTUs | British Thermal Unit, the primary heat measurement unit used by the hearth industry. It is the amount of heat required to raise the temperature of 1 lb. of water by 1 degree F. at sea level. |
| B-Vent | A gas-burning appliance that takes in combustion air from the home and vents products of combustion outside the home. B-Vent is also commonly known as natural vent. |
| Builder Series | Fireplaces specially designed for builders and contractors, featuring a beautiful blend of elegance, efficiency and economy |
| Chase | A structure built around, and enclosing, portions of the chimney and in some cases, housing the appliance. |
| Circulating Firebox | Has louvers at the top and bottom so that a fan can be installed. Louvers cannot be covered. |
| Clearance | The distance required by building and fire codes between stove, smoke pipe or chimney and combustible materials such as wood furniture or carpets. Clearances must be observed even if noncombustible plaster or other masonry materials protect the combustible materials, such as wood furniture or carpets. |
| Direct Vent | An appliance that draws combustion air from outdoors and exhausts it's combustion products to the outdoors eliminating the need for a standard chimney system. A glass panel in direct vent units is critical to keeping the combustion system sealed from the home, maintaining high efficiency and indoor air quality. |
| Electronic Ignition | Requires electricity to start the unit either 110 volt or battery. |
| EPA Requirements | Government regulations of wood burning appliances mandating that products sold after July 1, 1992 emit no more than 4.1 grams of particulate matter per hour for catalytic-equipped units and no more than 7.5 grams for non-catalytic-equipped units. |
| Firebox | That portion of the solid fuel appliance where the fuel is located and where primary combustion occurs. |
| Hearth | The floor of the firebox, most commonly used in reference to fireplaces. More generally, the foundation upon which fires for aesthetic and heating purposes are built. Differs from floor protection. |
| Inserts | Heating units that retrofit into an existing fireplace (masonry or factory-built). They burn wood, gas or pellets and offer superior efficiency. |
| Mantle (Flash Mantle) | A finishing option for direct vent and ventless fireplaces. They can be wood, marble or stone. The mantels do not encase the entire fireplace, but frame it. Therefore they are only 1 3/4 to 2 1/2 inches deep. Mantels are used when the fireplace is installed inside the wall or on the outside wall of the house. |
| Mantle (Cabinet Mantle) | Another finishing option for direct vent and ventless fireplaces. A fireplace cabinet is usually a wooden finishing option for direct vent or vent-free fireplaces which are installed on the floor of the room and vented through the wall. They encase the entire fireplace and can be made for walls or corners. They range from 13 to 28 inches deep. |
| Manually Controlled | Control the height of the flame at the unit only. |
| ODS | Oxygen Depletion Sensor - A safety device that activates the fire’s flame monitoring device in case excessive levels of CO² (deadly carbon monoxide), are detected. This would reduce the levels of oxygen, causing the pilot flame to become unstable and lift off the thermocouple tip. The fire then turns off automatically before the situation becomes dangerous. |
| Radiant Fireboxes | Also known as flush face. The facing (Stone, Tile, Brick) can cover above and below the fireplace opening. |
| Remote Ready | Able to turn the unit on and off remotely via a wired or wireless remote. Remote is sold separately. The height of the flame cannot be adjusted remotely. Not recommended for vented gas logs. |
| Surround | A marble or tile frame between the fireplace itself and the wooden mantel. Cabinets seldom use surrounds. However, some manufacturers do call a wooden cabinet a "cabinet surround". |
| Thermostatically Controlled | Senses the temperature at the unit not of the room. Not as versatile as a remote ready with a thermostat. |
| Variable Flame Height | Via the remote, you can increase and decrease the height of the flame and turn the unit on and off. Also available in thermostatically controlled. |
| Vent-Free | Gas appliance that has no need for a flue. Although vent-free units offer high efficiency, some areas may not permit their use. Please check with your local building official. |
| Zero-Clearance Fireplace | A factory-built fireplace that is constructed so that it can be placed, safely, close to combustible material. |
