Homebuyers consistently rate fireplaces as a must have in consumer preference surveys. However, many homeowners do not often use wood-burning fireplaces, because it can be time-consuming and messy to collect wood, build a fire, tend it, cool it down and clean up the ashes.
It is no surprise that gas hearth product shipments zoomed up 600 percent between 1992-2000, while sales of traditional cordwood appliances rose only 11 percent during the same time period, according to the Hearth, Patio and Barbecue Association.
Families who already have a masonry fireplace and a chimney in good shape can easily upgrade to a gas fireplace. And new manufactured gas fireplaces can be installed without a conventional chimney making some gas hearth products appropriate even for high-rise apartments.
Natural gas fireplaces, stoves, fireplace inserts and gas log sets burn more cleanly than wood fireplaces. This means no ash build-up, no creosote in chimneys and no sparks or flying embers that could burn holes in carpets or furniture. Natural gas hearth products are so clean, in fact, that they can be used anytime in areas of the country that have no burn regulations for wood fireplaces and stoves in an effort to reduce air pollution. Gas Fireplaces
Gas fireplaces are complete, prefabricated units that contain a gas fire within a prefabricated metal firebox. They come in a variety of sizes and styles, including see- through, three-sided and traditional fireplace configurations. The size of the firebox, the interior where the fire burns, typically varies from 32 to 45 inches in width. The fireplace can be placed along inside or outside walls, under windows, as a peninsula between rooms, in bookcases and media centers or in corners. These units can be vented up through the roof or through a side wall, or can be unvented. Some models use a fan or blower to circulate warm air from the fire into the room. Because no masonry work is needed, natural gas fireplaces are economical to install.
All natural gas fireplaces feature realistic gas logs with burning flames, and some can be used as supplemental heat. Gas fireplaces that are classified as decorative appliances are designed primarily for their appearance and the radiant heat they provide to a room. Some of these fireplaces can be equipped with blower assemblies that increase the amount of supplemental heat available.
Some types of fireplaces are classified as vented space heaters and are given efficiency ratings like furnaces and other types of vented space heaters. The efficiency rating is called its Annual Fuel Utilization Efficiency or AFUE. The AFUE for a fireplace takes into consideration the energy used while the fireplace is operating, any energy lost in start-up and shut down, and any fuel used in a standing pilot light. Fireplaces classified as space heaters contain a heat exchanger, a metal box used to transfer heat from the burner to the air to be circulated, and a blower or fan to move the warmed air through the room, usually through a decorative grill on the front of the fireplace. Gas Logs
Gas fireplace logs are constructed of ceramic fiber or concrete with a gas burner underneath. They are available in a variety of designs crafted to resemble real wood. The gas burner assembly creates a pleasant effect that suggests lively glowing embers. There are two types of fireplace log sets:
- Vented decorative gas fireplace log sets require leaving the fireplace damper open during operation. These sets are used primarily for ambience, since only about 10 percent of the log appliance s heat is retained in the room. Building codes usually require that the fireplace damper (the metal flap at the top of the firebox, leading to the chimney) be opened permanently with vented gas logs. As a result, glass doors are recommended for the firebox opening in order to keep heat in the room when the fireplace is not in use.
- Vent-free log heaters can contribute to heating a room, and can be used with the fireplace damper closed. A sensor in the unit monitors the percentage of oxygen in the room and automatically shuts the log set off if the level drops beneath its set point. Local building codes vary on installation of these units.
Gas Fireplace Inserts
Another option for an existing fireplace is a gas fireplace insert. These units can upgrade an inefficient wood fireplace into a good source of extra heat. An insert is composed of a set of gas logs built into a steel or cast iron box, usually with a fan or blower to move heat into the room. Inserts can fit into almost any existing fireplace and come in a wide variety of styles and sizes. Vented decorative models come in an airtight metal cabinet with sealed glass door. They sometimes require a chimney liner to ensure proper venting. Vent-free heater models do not require sealed glass doors since all of the heat produced goes into the room. Units can be controlled by a switch, remote control or thermostat. Gas Stoves
Country, rustic or western-style homes are particularly well suited to gas stoves, which provide warmth with the look of a blazing fire. Gas stoves are good substitutes for more polluting wood-burning stoves. These units are freestanding, come in traditional and contemporary styles, and are available in vented and vent-free models. The stoves offer realistic flames, good heating capacity, high efficiency and an attractive appearance.
The heat output of gas stoves can be adjusted by turning the burner up or down, by linking the unit to a thermostat or by using a remote control. During power outages, gas stoves can provide heat as long as the pilot light is on. Energy Use and Operating Costs
It would cost only 21 cents per hour to operate a gas log set for one hour based on a log set that burns at the rate of 25,000 Btu per hour and a national average 2001 natural gas cost of 83 cents per therm (a therm = 100,000 Btu). In terms of energy consumption, natural gas fireplace equipment is rated by the number of British thermal units (Btu) used in an hour (Btu/hr). Larger Btu numbers indicate more fuel usage and, potentially more heat created. Most vented gas log sets and fireplaces are in the 20,000 to 60,000 Btu/hr range. Vent-free heater products have an upper limit of 40,000 Btu/hr.
Bharat Gas Agency