Save Money with a New, Energy-efficient Furnace

Enlarge Image Image Gallery Investing in a new, energy-efficient furnace may save you money in the long run, especially with increasing fuel costs. KEITH WARD

Although the number of homes heated by clean, renewable solar energy is growing, the majority still rely on fossil fuels (natural gas and fuel oil) or electricity generated by nuclear and coal-fired power plants. With the cost of these fuels on the rise, it’s becoming increasingly expensive to stay warm in the winter. Fossil fuel combustion also contributes to climate change, as well as acid rain and air pollution.

Concern for these issues has caused many people to consider replacing old, inefficient furnaces with energy-efficient models. If your furnace is more than 15 years old or is frequently in need of costly repairs, or if you’re planning to add on to your home and need to upgrade your furnace to heat the additional space, consider installing an Energy Star-qualified model.

Heat pumps, solar hot water systems and woodstoves are excellent options, but they don’t fit everyone’s budget, home or lifestyle.

An energy-efficient furnace will cut your utility bill substantially, saving hundreds of dollars a year. (See Savings from an Energy-Efficient Furnace.) By reducing electricity use, efficient furnaces help reduce air pollution produced by conventional power plants. They also can improve the air quality of your home.

Before you invest in a new furnace, it pays to make your home more energy efficient. Some actions you can take include sealing the leaks in the exterior walls, attic and roof; then adding insulation and installing insulated window shades. These and other projects will save money over the long haul and could even allow you to reduce the size (heat output) of your new furnace — smaller furnaces cost less.

Numerous companies manufacture high-efficiency furnaces for forced-air heating systems. Let’s review the options and features you should look for.

Gas Furnaces

Conventional gas furnaces are usually located in a basement, utility room or a well-vented closet. They contain a combustion chamber where natural gas or propane is burned. The burner is ignited by a pilot light, a flame that burns 24 hours a day.

In a conventional furnace, air from rooms in the house enters the furnace via the cold-air return ducts. Heat generated in the combustion chamber is transferred via a heat exchanger and distributed throughout the home by a duct system. The heated air is propelled through these ducts by a powerful (and sometimes noisy) electric blower. Waste gases (containing toxic pollutants) from the combustion chamber are vented to the outdoors through a flue pipe. As the hot gases rise, they create a partial vacuum in the combustion chamber. This draws air from the house into the fire, ensuring the continuous supply of oxygen required for proper combustion. The rise of hot air, together with the inflow of air, is known as draft.