image of blue furnace flames

HVAC experts strongly recommend practicing proper maintenance and care for your home heating equipment to prevent common problems, especially issues with a cracked heat exchanger. If your heater has a cracked heat exchanger, several signs will help you identify the problem. Find out what the heat exchanger in your home furnace is, why this component is so important, and how to verify that you have a cracked heat exchanger.

What Are Heat Exchangers?

Within the heating system, the heat exchanger is an incredibly important component that moves heat from fluid to fluid to either warm the home up or cool it down. In a residential heating system, the heat exchanger warms the air that moves through the home ventilation. Combustible gas collecting in the heat exchanger rises in temperature to increase the temperature of the indoor air. Having a cracked heat exchanger can have a very adverse effect on the overall performance of your home heating equipment.

Signs The Heat Exchanger In Your Home Furnace Is Cracked

Be on the watch for symptoms of a cracked heat exchanger like:

Changes In How The Flame Looks

In a normal gas furnace, the flame will usually appear blue. A blue flame means that your furnace is working as it should. If this flame turns yellow, however, it might mean that your burner needs to be cleaned, or worse, that the heat exchanger is cracked. Standard heating systems have steadily burning flames. When the flame flickers, the unit likely has an internal problem of some sort.

image of soot

Soot Build-Up

Soot develops due to accumulations of carbon within the furnace. This is usually the case when the furnace is not clean and completely burning fuel, as the result of a poorly adjusted burner or a cracked heat exchanger.

Corroded Or Cracked Components

Inspect the components throughout your home furnace for evidence of cracking and rust. If there are physical problems with the exterior components, it may be that the system’s internal components are damaged also.

Suspicious Furnace Smells

When the heat exchanger is cracked, the heating system will emit strange, unpleasant smells, including an odor that is not unlike that of formaldehyde. This can have a negative impact on resident health and may cause extreme headaches. When this occurs, contact a licensed HVAC contractor right away to have your home heating system inspected.

image of man covering nose from bad furnace odor

Resident Health Problems

Carbon monoxide from furnaces can also lead to recurring health issues, including nausea, disorientation, sleepiness, irritation of the nose and eyes, and many other flu-like symptoms. These are typically experienced only at home.

What Causes Heat Exchangers To Crack?

Overheating is the most common cause of a cracked heat exchanger. This is often the result of insufficient airflow. This problem is often avoidable with regular and diligent heater maintenance. As dust, dirt, and other particulates continue to accumulate within the furnace, the filter becomes blocked, and clogs can develop throughout the blowers and coils. This impedes overall airflow. Air is essential for maintaining internal furnace temperatures, and for the absorption of extra heat. When the internal temperature rises, the likelihood of the heat exchanger cracking rises as well.

Worn control valves can also be the cause of a cracked heat exchanger. As these components become worn, the pressure increases to a level that the exchanger simply cannot tolerate. As such, you should have your furnace regularly inspected to identify possible problems before they spiral out of control.

image of interior of a broken furnace

The Issues That A Cracked Heat Exchanger Will Cause

As a homeowner, you will find that having a cracked heat exchanger is far more than a mere inconvenience. This is a problem that can be a real threat to your personal safety and home. A lot of people power their home heating systems with propane, natural gas, or fuel oil. All of these are fossil fuels that create fumes when burned. Fumes can include carbon dioxide, water vapor, soot, and carbon monoxide. If harmful gases increase to high levels, serious health issues can arise throughout the entire household.

How To Resolve A Cracked Heat Exchanger

Once your heat exchanger cracks, you should not try to repair it on your own. If you do indeed have a cracked heat exchanger, this component will need a replacement. Sometimes, your entire heating system may need a replacement. In either case, the job will require serious skill and consideration. A licensed HVAC professional can test and inspect your home heating equipment to identify the source of the problem. They can then give you a recommendation for repairs. Your provider will also give you information on properly caring for your furnace.


A cracked heat exchanger can cause considerable damages to the entire heating system. It can additionally be a major health hazard. Fortunately, this issue is a largely preventable one. With proper and regular maintenance and care, the heat exchanger in your furnace will continue to function as it should for many years to come. If you have any furnace concerns, reach out to a local HVAC company right away to talk about possible solutions and preventative measures. The better care that you give your furnace, the longer it will last, and the better it will ultimately perform.

Contact Tower Energy For Furnace Services Today

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Tower Energy provides first-rate heating and cooling solutions throughout the local area. Our team of top NATE-certified technicians is capable of performing superior HVAC replacements, tune-ups, and repairs. They are sufficiently knowledgeable about servicing your home HVAC equipment correctly the first time.

Does your home furnace need to be replaced? You’re in excellent care with Tower Energy. We guarantee the most competitive local prices on furnace replacements and repairs. If you need a new system for your home, we can help you find the best model for your needs and your budget. As ever, our top priorities are indoor comfort, energy efficiency, air quality, and more. To set up your appointment or to get a no-cost, in-home estimate, call Tower Energy now.

Contact us now or call us at (860) 677-7347 to find out more.