Highlight on High Efficiency Furnaces

What Is a High Efficiency Furnace?

A high efficiency furnace is a unit with an AFUE at 90% or higher. AFUE, or annual fuel utilization efficiency, is the measurement used to determine a furnace’s fuel efficiency. A furnace’s efficiency rating is noted on the furnace’s nameplate, usually located inside one of the removable access panels on the front of the unit.

High efficiency furnaces are built using new technology and features that simply do not exist on older models. Advancements in heating technology allow high efficiency furnace units to create more heat from the gas or fuel they use, while only using the minimum amount of energy required to do their job.

High Efficiency Furnace Features

High efficiency gas furnaces typically utilize advanced components and technology to deliver better energy efficiency over other models.

• Electronic Ignition: Older gas furnaces are started by gas-burning pilot lights. New high efficiency furnaces feature electronic ignition that is only utilized when the furnace is signaled to come on. This feature conserves energy over a constantly-burning pilot light.

• Two-Stage Heating: Two-stage heating allows high efficiency furnaces to operate with lower energy consumption when temperatures are mild. When temperatures are very cold, the higher stage works to keep your family warm, preventing discomfort.

• Second Heat Exchanger: High efficiency furnaces are also called condensing furnaces. They utilize a second heat exchanger to extract heat that would otherwise escape your system through vented exhaust gasses, gaining more heat from the energy consumed.

• Variable Speed Blower: A variable speed blower can operate at difference speeds based on the home’s current needs. It works at faster speeds when more airflow is needed, and switches to a lower speed when less will do.



• Sealed Combustion: Sealed combustion allows the furnace to draw in outside air for the combustion process, conserving energy and making the process safer for your family.

Shopping for a High Efficiency Furnace

High efficiency furnaces turn more of the money you’re spending on energy into heat, compared to lower rated models. These furnaces are typically more expensive to install compared to lower efficiency models, but users make their money back in energy savings over shorter periods of time, depending on usage.

When shopping for a high efficiency furnace, compare features and efficiency ratings of the models you are considering. Obtain quotes from reputable HVAC contractors to learn the total cost of the furnace and its installation – several factors can affect installation costs, including ductwork installation or repair for improved efficiency.