It sometimes happens when a technician is called for an HVAC visit that he finds a crack in the heat exchanger. Generally, this is viewed as a problem, and can lead to the furnace being red-tagged, or shut down. What is a heat exchanger, and why is a crack considered so serious? What is a heat exchanger?Home heating units use a heat exchanger to transfer combustion. A gas furnace mixes gas with air to create the heat that circulates through your house. A crack in the exchanger interferes with the normal mixture of gas and air causing improper combustion. The result can cause furnace malfunction or a buildup of carbon monoxide (CO) in the system or in your home. Since CO is an odorless gas that's potentially lethal and undetectable without testing, a buildup could occur without your knowledge. If you suspect a crack in the exchanger, shut off the furnace and do not run it. Have a professional HVAC technician inspect your furnace.What causes cracks?As the furnace heats up and cools down, the metal contracts and expands, which can cause cracking over time. This is normal and occurs with all furnaces over time; however cracks can occur due to:
Incorrect airflow – Blocked vents, ducts, flue or chimney; dirty air filters
Incorrect combustion – Burners are not firing correctly
Condensation – Condensation builds up in the heat exchanger causing corrosion
Are cracks significant?Small holes or cracks can exist in the exchanger unit for years before they're noticed. They may not do damage or cause your furnace to malfunction, but they should be checked. Small cracks can get larger over time and cause furnace problems, especially in older models. Cracks can cause the blower to force the burner flames out the front of the furnace causing a fire. Holes can keep the burners from igniting or blow out the pilot light causing the possibility of an explosion.Regular maintenance and service can prevent problems with your furnace, especially those that may be hidden. Each of our technicians carry specific analyzing technology that to make sure your furnace is safe. Most companies may only have one of these machines for the entire company use. Therefore you can feel secure you're getting the very best inspection each and every time. For more expert advice about heat exchanger cracks or home comfort needs, please feel free to contact us at Air Assurance, serving the greater Tulsa metropolitan area since 1985.Our goal is to help educate our customers in the Tulsa and Broken Arrow, Oklahoma area about energy and home comfort issues (specific to HVAC systems). Image courtesy of Shutterstock