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Family-Owned and Locally-Operated in West Houston

Family-Owned and Locally-Operated in West Houston


Cool Care Heating and Air Conditioning Blog

What’s the Deal with a Cracked Heat Exchanger?


When folks throughout the country hear mention of Houston, they think of our sweltering summers. But as you’re well aware if you’ve lived here for even just a year, our winters pack quite the punch and, as a result, you use your heater on a very regular basis during this time of the year.

Did you have your heating system tuned-up by a professional before winter started this year? The good news is, if you didn’t, it’s not too late! The only time it’s ever too late for maintenance is if your heater completely broke down, to the point that no repairs will help anymore. Skipping maintenance even just one fall/winter season could leave you with emergency repair needs.

One particular repair need that could be dangerous, especially if you have a gas-powered heater, is a damaged heat exchanger. This is not to say that gas-powered systems are inherently dangerous! But they can become so if they’re not properly cared for. Read on to learn why heat exchangers matter so much when caring for your gas-powered heating system.

What Is a Heat Exchanger?

This is the component that even makes it possible for your furnace to provide heat into your home. When the burners come on, the heat exchangers are filled with hot combustion gas. They have metal walls that get very hot due to these combustion gasses, and then air travels over it, picking up the heat before going through your ductwork and into your home.

This setup means that the only thing that stand between your indoor air and combustion gasses is the heat exchanger.

When everything is operating as it should, when a heating cycle stops, the combustion byproducts that have gathered in the heat exchanger are vented out of the furnace through a flue that releases the gas outdoors, harmlessly.

The Problem with a Damaged Heat Exchanger

The heat exchangers in your furnace expand and contract as they heat up and cool down. This strain on the heat exchangers can lead to small cracks and fissures forming on the metal walls. Corrosion can occur due to the reaction between the metal walls of the heat exchanger and the combustion gasses. This is usually only a problem if the furnace isn’t vented properly, but corrosion should never be ruled out, especially if you have a particularly old furnace (10-15 years old).

The cracks and fissures that we are referring to are going to be microscopic—the average human eye wouldn’t see them. But when the heat exchangers are hot, these cracks open up enough that the combustion gasses could potentially enter your living space. The most harmful of these is CO (carbon monoxide), which leads to hundreds of illnesses and fatalities in the U.S. every year.

“Do I Have a Cracked Heat Exchanger?”

Now you know why a cracked heat exchanger is a problem, but how do you know if you have one? There are a couple of signs. First is age—if your furnace is 10-15 years old, especially if it hasn’t been well-maintained, there’s a good chance that heat exchanger damage can occur. Second is a clicking noise. When your furnace cycles off, do you notice clicking you haven’t heard before? This can be the metal walls of the heat exchangers contracting as they cool down.

Contact Cool Care Heating and Air Conditioning for expert furnace service in Houston, TX.

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