The heat exchanger is the part of your furnace that is responsible for generating hot air. To create heat, your furnace burns natural gas. When gas is burned, exhaust byproducts travel through the heat exchanger. As the exhaust passes through the furnace’s exhaust outlet, metal is heated. Simultaneously, this hot metal heats the air. From there, your furnace system distributes hot air to your home through your air ducts.
In order to function properly, the heat exchanger must remain sealed. That is why cracks are detrimental.
What Causes A Cracked Heat Exchanger?
The air inside your furnace and heat exchanger gets extremely hot. As a result, this extreme heat causes the metal inside the heat exchanger to expand and contract. Though well-maintained heat exchangers are built to tolerate this heat, eventually this stress causes cracks.
If your heat exchanger is several years old, stress cracks are common. However, if your heat exchanger is under 10 years old, there are other causes of cracking. Causes of premature heat exchanger cracking include limited airflow, and your furnace being too large for your home.
Limited Airflow
Limited airflow to your gas furnace is the result of blocked registers. If registers in the home are blocked, pressure builds up inside the furnace which causes cracks. It is important to note that a clogged furnace filter or obstructed air ducts are also causes of heat exchanger cracks.
Is Your Furnace Too Large For Your Home?
If your furnace is too large for your home, this is an issue because it may ‘short cycle’, meaning it turns on and off frequently. Therefore, your heat exchanger expands and contracts more, resulting in overuse of your furnace system and premature cracks.
Why Cracked Heat Exchangers Are A Problem
If they are not dealt with, cracked furnace heat exchangers can pose a serious safety risk. If you notice a strange smell coming from your furnace or signs of rust along the exterior, this may indicate that there is a problem.
Carbon Monoxide Leak
Because heat exchangers contain carbon monoxide, sulfur dioxide, and nitrous oxide, a crack in your heat exchanger means these harmful gases could escape into the air ducts of your home. A carbon monoxide leak can result in illness and even death.
Flame-Out or Fire
Another risk of a cracked furnace heat exchanger is a flame-out or fire. When gas and air combust in the heat exchanger, the gas builds up. This build-up of gas often reaches a high enough volume to be explosive. As the gas becomes explosive, it will force flames and air pressure out of any hole it can find, such as a crack in the heat exchanger.
Unfortunately, unless your carbon monoxide detector beeps or you notice rust, you may be unaware your heat exchanger is cracked. In order to know for sure, an inspection by a professional technician is required. If you suspect your furnace heat exchanger is cracked, it is important to contact a technician immediately so it can be replaced in a timely manner.
These are just a few causes of cracked furnace heat exchangers and why they are a problem. Be sure to schedule your routine furnace maintenance to ensure your furnace is safe to operate this winter. If you need any assistance with your furnace or home heating equipment, do not hesitate to
contact our team at JOB Heating & Air Conditioning.
JOB Heating & Air Conditioning are Trusted Saskatoon furnace experts. They show up on time, deliver on budget, and leave the work area cleaner than when they arrived! They take pride in their work in this city and surrounding area, so nothing means more to us than testimonials from their clients as their preferred plumber in Saskatoon.
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