First off, a point we want to make clear is that a cracked heat exchanger means more for your home, health, and safety in general than it does simply the furnace. We don’t say this to send you into panic mode, but rather to stress the importance of caring for your furnace properly.
Furnace care involves scheduling maintenance each and every year, for starters. Maintenance allows our technicians to thoroughly inspect, clean, and adjust all the components of your heating system, ensuring that it operates as effectively and efficiently as possible. Maintenance also helps prevent repair needs, because it gives our professionals the opportunity to find small issues before they become bigger ones.
And one “small” issue that could quite literally become a big emergency is a cracked heat exchanger. This is more common in older systems (those that are 10-15+ years old) but even if you have a newer system, it’s a good idea to understand what a heat exchanger does, and why a damaged one is bad news. Read on!
The Purpose of the Furnace Heat Exchanger
The heat exchanger of your furnace is the component actually responsible for heating up the air that then travels through your ventilation system and into your home. When the burners of the furnace ignite, they produce hot combustion gasses that are collected inside the heat exchanger. The component itself looks like a metal, clam-shell shaped chamber, or a series of chambers.
The gas in the heat exchanger heats up the metal walls. Then the air from the blower fan travels over the heat exchangers, picking up that radiant heat and dispersing it into your living space. So, the combustion gas is responsible for heating your home, but without making contact with your indoor air!
That is, unless you have a damaged heat exchanger. A fully operational heat exchanger system will allow the combustion byproducts to vent out through a flue outside of your home. A cracked heat exchanger can allow gas into your home.
The Danger of a Cracked Heat Exchanger
Since the metal of a heat exchanger expands and then contracts as it heats and cools, the strain could eventually cause fissures in the metal. They will be microscopic to the naked eye, but every time your furnace comes on, the metal can expand and leak out gas—the most harmful gas being carbon monoxide (CO).
In the best case scenario, CO exposure can lead to headaches, minor dizziness, and sleepiness. But enough CO exposure can lead to much worse symptoms, and even fatalities. So, it’s imperative that you have this problem taken care of right away.
“Can a Heat Exchanger Be Repaired?”
Theoretically, yes. Either a cracked heat exchanger can be repaired or replaced. But if your furnace is on the older side anyway, it would probably do you best to upgrade the entire system. Once a furnace has reached a decade or more in age, it’s unable to work as efficiently as possible. It would save you more money month to month to replace the system altogether!