High-Efficiency Gas Furnace

A standard gas forced air furnace wastes about 30 cents of every fuel dollar. Older furnaces can waste even more. By taking advantage of the latest technology and installing a new high-efficiency furnace you can save energy dollars and improve comfort.

Most new high-efficiency furnaces have an Annual Fuel Utilization Efficiency (AFUE) of 90% or higher. The AFUE indicates the percentage of fuel turned into heat. The higher the AFUE, the more efficient the unit and more energy dollars you can save. High-efficiency furnaces tend to be slightly more expensive than the standard type, however the additional cost is offset by the increased energy savings.

New residential furnaces are required to display an EnergyGuide label which compares annual fuel costs with those of other similar sized units. (An example of the information included on the EnergyGuide label is shown below.)

Some of the recent developments in high-efficiency furnaces are:

• Electronic Spark Ignitions or "hot surface" ignitions eliminate the need for continuously burning pilot lights which waste fuel and increase operating costs.
• Condensing Furnaces (most 90% furnaces are of this type) draw enough heat out of the combustion gases that moisture in the gas condenses releasing additional useable heat. Exhaust gases from a condensing furnace are cool enough that they are vented through a wall with plastic piping.
• Pulse Furnaces burn gases in small explosive pulses, much like a car engine. Pulse combustion allows the maximum amount of heat to be extracted from the burning fuel. These furnaces can achieve AFUE ratings as high as 97%.
• Automatic Vent Dampers close the flue pipe when the burners are off and reduce the amount of inside air drawn up the chimney.