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Just What Is a Condensing Furnace?


Part of my job is keeping track of developments in comfort technology. Most dogs are interested in only one type of heating technology, which is their fur. I love my fur, but I also love knowing about furnaces and the ways they keep making it easier for humans to stay cozy in winter.

So today I want to talk about one of the best developments in furnace technology, the condensing furnace. Sort of a funny name, but it’ll make sense when I explain it. If you are considering getting a new furnace in Louisville, TN, a condensing furnace might be on your list if it suits your home and current needs.

Double Heat Exchangers

The big difference between a condensing furnace and a standard furnace is that a condensing furnace contains two separate heat exchangers. These are the metal containers that hold the hot combustion gas from the burners and then raise the temperature of the air blown around them by transferring heat from their surface. Heat exchangers are why you get warm air sent around your house.

A standard furnace has one heat exchanger. Once the heating cycle is done, the combustion gas in the exchanger cools down and becomes a vapor. This vapor then goes safely out a flue and out of the house. A condensing furnace, however, has the second exchanger, and this is where the combustion gas vapor goes next.

Squeeze That Fuel for All the Heat It’s Got!

What happens in the second exchanger is the condensing part. The vapor is condensed in this exchanger. If you remember some of your high school science class, you’ll recall that when you condense a liquid, it releases heat. Condensing the combustion vapor in this second exchanger puts out even more heat to be transferred to the air moving around the exchanger. It’s getting every drop of energy possible out of the natural gas. The remaining vapor then exits out a flue. 

Are These the Best Furnaces to Get?

Well … no. Here’s the tricky part about home heating: there is no such thing as a “best” system. If there were, everybody would have that one and I wouldn’t be writing a blog! Condensing furnaces have plenty of advantages, and the top is that they convert more of their fuel source into heating thanks to that second condenser. 

But there are a few drawbacks to consider. For example, to put in a condensing furnace, you may also have to make changes to the venting for the furnace. Condensing furnaces are also more expensive to install, and your home may simply be better off with a standard furnace—there are many excellent models that meet your needs.

Finding the Ideal Home Heating

I’m glad to share this information with you, but if you want answers that apply to your home, you’ll need to call our team and talk to our installing pros. We have many great options when it comes to home comfort, such as our Onyx equipment line. First and foremost, we look out for your family’s comfort!

Stay warm,