How to Choose: Conventional Furnace Vs. Condensing Furnace

 If you’re serious about investing in a high-efficiency heating system, a condensing furnace is one of your best options. Condensing furnaces come with the highest AFUE ratings available for gas furnaces and can save homeowners a lot of money over the lifespan of the units. 

So what exactly is a condensing furnace and what makes it more efficient than a traditional unit?

Cold person laying on the couch under a blanket.

What is A Non-Condensing (Conventional) Furnace?

Conventional furnaces are built with just one heat exchanger. During the combustion process that takes place inside of this heat exchanger, a certain amount of the heat that is produced is lost up the chimney in the form of water vapor. What this means is that conventional furnaces lose a significant percentage of the heat that they use energy to produce.

What Is A Condensing Furnace?

Condensing furnaces have a second heat exchanger that is able to extract extra heat from that water vapor that would normally be vented out of your home. This allows them to make more use of the energy that they consume and can significantly reduce their operating costs.

How Does A Condensing Furnace Work?

At the beginning of the heating process, a condensing furnace works similar to a traditional furnace. Gas burners deliver heat into the first heat exchanger and the combustion process leaves a byproduct of hot water vapor. That water vapor is next sent to the second heat exchanger where it is condensed and turned into a liquid.

When a gas turns into a liquid, it releases heat. Your furnace is able to use that extra heat to warm your home. The resulting liquid is then drained out of your home through a PVC pipe.

How Efficient Is A Condensing Furnace?

Because condensing furnaces are able to do more with the fuel that they consume, they come with higher AFUE ratings than traditional furnaces. In fact, condensing furnaces have AFUE ratings of at least 90 percent, with higher-efficiency models reaching AFUE ratings in the upper 90 percentiles.