What Are the dangers of a cracked heat exchanger?

Having issues with your gas furnace? Perhaps you’ve heard of the potential danger of a cracked heat exchanger. Even if your furnace looks fine, a cracked heat exchanger could lead to dangerous gases being leaked into your home. These dangerous gasses can seriously affect those who are exposed to them. When it comes to a damaged gas furnace, it’s important to take it seriously for the safety of your home. 

What is a Heat Exchanger?

A heat exchanger is the furnace’s component that actually heats the air that flows through the system. It is made up of a set of tubes and coils that loops the airflow through the furnace to heat the air inside. A crack in these tubes and coils can lead to the gases being burned in the furnace, such as carbon monoxide, sulfur dioxide, and nitrous oxide, leaking into your home. These dangerous gases can cause illness, or in extreme cases, death. 

How can you tell if it is cracked?


Evidence of soot, a black carbon buildup, on the inside of the furnace is a sign that there could be improperly adjusted burners or a cracked heat exchanger. Soot is caused when your furnace isn’t burning cleanly, like when there is incomplete combustion. 

Corrosion and cracks on furnace components

Stress cracks and other signs of wear and tear on external parts of your furnace can be signs that internal parts are suffering the same wear. Cracks are pretty common, they happen with the expanding and contracting of components during heating and cooling. Components can also become corroded when exposed to fumes emitting chloride or moisture from other sources. 

Water on the floor

Water on the floor at the base of your furnace can be signs of a condensation issue or a cracked heat exchanger. 

Strange smells

A malfunctioning heat exchanger can create a strong, unpleasant odor similar to formaldehyde. People exposed to it may experience headaches, as well as other physical symptoms. 

Other physical symptoms

Along with headaches, flu-like symptoms can also indicate a cracked heat exchanger. Leaking gases can cause nose and eye irritation, sleepiness, disorientation, and nausea in those exposed to it. Be sure to keep a carbon monoxide sensor and test it regularly so that your family can be protected from undetectable gases. If these symptoms start at home and stop when you leave, it is a good idea to have your furnace inspected immediately. It could be a dangerous sign that your heat exchanger is leaking fumes. 

What should you do if you suspect a cracked heat exchanger?

If you are experiencing any of these signs it is a good idea to call a professional. They have the knowledge and tools to identify and repair the issue. Stop running your furnace immediately if you have symptoms from leaking gases or suspect your heat exchanger might be cracked. Call A/C Masters and we will come and inspect your furnace and repair or replace the heat exchanger or furnace.

If your furnace is older than 10 or 12 years, it is a good time for a replacement. Issues with furnaces usually start occurring when these systems reach this age and you don’t want to pay for repairs on a furnace that will break within a few years. If it’s time for a furnace replacement contact A/C Masters and we will be happy to give you a free estimate on any repairs or replacements. Call 757-898-2894, 24/7 in case of an emergency.

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