Wednesday, June 3, 2009


Keep the home fires burning--cleanly and efficiently

Energy efficient fireplaces

Let's say you have a basic wood-burning fireplace. Charming as it may be, this old-fashioned device pollutes the air and sends a large amount of its heat roaring out the chimney. But there's no need to get rid of your old fireplace. You can insert an energy-efficient gas-burning fireplace. Many models produce the same comforting yellow-orange flames that you enjoy in a wood fireplace and even contain "logs" made of fireproof material so realistic you would have to look closely to tell the difference. And you don't have to bother with wood and ashes.

Gas fireplaces are usually meant to heat an individual room rather than an entire house. But some models can put out 40,000 Btu--as much as some furnaces. If you have a small house, this could be enough heat for all the rooms.

Top Tips

When shopping, look for

  • Energy efficiency. Like the other types of heating systems we discuss, gas fireplaces are rated by the amount of heat they can produce in British thermal units, or Btu, and by their efficiency. The higher the efficiency, the less the unit will cost to operate. Once the heater is up to the desired temperature, some gas models convert almost 90% of the gas they burn into usable heat. In comparing fireplaces and stoves, you should also consider their Annual Fuel Utilization Efficiency (AFUE), which is a measure of the average efficiency.

  • The right size. The heating capacity of your gas fireplace should calculated carefully, taking into account the climate in your area, room size, ceiling height, quality of insulation, windows, and so forth. A typical residence needs roughly 35 Btu per square foot per hour. So if the room you plan to heat is 20 x 20 feet, or 400 square feet, you would need roughly 400 x 35 or about 14,000 Btu of heat. With a heater that's, say, 80% efficient, you'd need an input of 17,500 Btu. It would be foolish to spend more for a higher capacity heater.

  • A thermostat. Relying on how you feel to decide when to turn a heating device on and off can waste energy. Therefore, it's best to have a thermostat to regulate the temperature of the heater.

  • Electric ignition or low-energy pilot. Electric ignition of the fireplace is more efficient than a gas-powered pilot light, because the gas pilot burns constantly. However, if electric power outages are a problem in your area, you may want to choose a model with a pilot light. If you do, try to get one that 1) burns a minimal amount of gas and 2) is easy to relight or extinguish. This way, in hot weather, when there's no need for the fireplace, you can turn the pilot off, and you won't have a big hassle when you need to turn it back on.

Other Considerations

  • Gas fireboxes installed in existing fireplaces vent fumes from combustion out through a flue installed inside the existing chimney.

  • Gas fireboxes can also be used in homes that don't have fireplaces. They are designed with vents that safely send combustion gases straight out through the wall instead of up the chimney, helping you avoid the expense of chimney repair, upgrade, or installation. If proper venting is possible, these "direct vent" fireboxes can be included as part of any remodeling project if you want the feeling of a fireplace. The same is true of the freestanding fireplaces that look like wood stoves. (Non-vented fireplaces are also manufactured. But they are banned in some states, while in others they may be used only if there is a carbon monoxide detector in the house. )

  • A gas fireplace may even lower your heating bill. How much you turn up the thermostat is largely determined by how comfortable you feel in a given spot. If people in your house tend to spend a lot time one room, you can practice "zone heating," by turning the heat down in the rest of the house and sitting comfortably by your fire while using less energy.

  • Models with built-in fans gently circulate the air. They're worth considering in large rooms, or in rooms where you spend time at some distance from the fireplace.

  • Gas fireboxes cost about $1,200 to $3,200 depending upon their capacity and whether they have extras like a fan and a thermostat (not including installation).

Benefits you
A gas fireplace can give you the cozy feeling of an old-fashioned hearth with none of the hassles. your wallet
A modern gas fireplace can save money on heating, especially if it allows you to turn down heat elsewhere in the house. the planet
Efficient new gas fireplaces emit much less global-warming carbon dioxide than the old models and, if strategically placed, can help you burn less fossil fuel throughout your home.

Common Mistakes

Thinking bigger is better. Don't waste gas by buying a gas fireplace that is too big for your room.

Getting Started

Installing a gas fireplace or freestanding gas stove is not something that should be attempted by most do-it-yourselfers. There are code and safety issues that require professional attention. After finding a model you like, hire a licensed heating contractor who has experience with these systems to do the installation.

No comments:

Post a Comment