What a Furnace Heat Exchanger Is and Why It Matters

Many homeowners in our area have gas-powered furnaces in their households to keep their families warm. A furnace is an excellent choice—it’s powerful and cost-effective. Today’s models even have a higher efficiency rating than just a decade ago, with the highest AFUE (annual fuel utilization efficiency) rating for a gas furnace being 98%. Trust us when we say that’s an efficient heater!

But in addition to efficiency, you want to be able to rely on safety when it comes to your heating system. That’s not to say that gas-powered furnaces are inherently dangerous. But if you don’t properly care for yours, it can become dangerous.

The most common cause of an unsafe furnace—particularly an aging one—is a cracked heat exchanger. Even if you don’t have a problem with a heat exchanger, if your furnace is 15+ years old, it’s time to start looking into an upgrade. We’ll dive more into the “why” of this below.

“First Off, What Does a Heat Exchanger Do?”

We’re glad you asked! This component is not just important to the operation of your gas-powered furnace, it’s vital to it. The heat exchangers are where the heat from combustion gas collects to heat up the metal walls so that air can pass over them and bring heat into your home. In other words, the heat exchangers are the part of your furnace responsible for safely bringing warmth into your home.

Combustion gas enters the clamshell-shaped chamber of the heat exchanger. This gas raises the temperature of the metal walls. The blower fan pushes air over those metal chambers, and the heat transfers to the air. That air then travels through your ductwork and into your home. The metal walls of the heat exchanger are the only thing that stands between the combustion gas and your indoor air.

The Danger of a Damaged Heat Exchanger

Over the years, wear and tear affects your furnace, including the heat exchangers. Every time the heat exchangers get hot, their metal walls expand. They contract when they cool down. After years of this, they’re susceptible to corrosion and subsequent cracks.

These cracks are small—invisible to the naked eye. But when the heat exchangers get hot again and expand, the cracks open up and can leak combustion gas out. When a furnace is well ventilated, this might not be a problem. But there’s one combustion gas in particular—carbon monoxide (CO)—that can be very harmful if it does enter your indoor air.

CO poisoning is the cause of hundreds of illnesses and even fatalities each year. Allowing your furnace to continue operating with a cracked heat exchanger increases the potential of this problem affecting your family. If you have an older furnace, or if your furnace hasn’t been professionally maintained in the past year, then it’s time to give our team a call to schedule a tune-up and maybe even consider a heating system upgrade.  

Schedule your Tallahassee, FL furnace repair with the pros here at Parker Services Inc. Comfort’s Just a Call Away.

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