Is a Cracked Heat Exchanger a Problem?

If you have a gas furnace, you’re at risk for a cracked heat exchanger. If you’re unsure what that is, or even if you have a furnace or a heat pump, it’s okay. Let’s review these questions and answers. It’s important because the information could lengthen the lifespan of your equipment, save you money as well as eliminate safety risks.  

Do You Have a Furnace or a Heat Pump?

Let’s start here, because many homeowners, especially newer ones, don’t know. Simply, the difference is most people have one or the other.   A heat pump heats and cools a home and is one unit. Heat pumps often use a component called an air handler, to improve the performance and efficiency of the heat pump.   Other homes use a furnace to heat and an air conditioner to cool. If you don’t know what you have, take a look at the big metal box outside your house. This is the condensing unit. You should find a model number on it. Search online and the manufacturer page will identify it as a heat pump or an air conditioner. If it’s an air conditioner, then your heating unit indoors is a furnace.  

What a Cracked Heat Exchanger in a Furnace Means

First, the heat exchanger is a central component in a furnace. The heat exchanger is the source of the fuel combustion. According to a U.S. Energy Information Association survey of 42.6 million homes, 57 percent use a central furnace.   Second, when a gas furnace combusts fuel to create heat, it does so in the heat exchanger. The blower motor blows air across the heat exchanger where the air absorbs the heat. The air continues on and out of the furnace. Finally, it travels through the ductwork to the rooms of the home.  

Cracked Heat Exchanger Causes

There are a couple ways a heat exchanger can become cracked.   One is simply over time. When you purchase a furnace, most will have various types of warranties. Some will have a parts warranty, a unit replacement warranty, a heat exchanger warranty or some combination of the three.   It’s important to note the heat exchanger warranty because it’s such a critical component. It’s also a significantly expensive part to replace.   The other cause is overheating. A heat exchanger can overheat due to a few reasons. The most common are equipment strain and airflow obstruction. These are related issues. When the airflow is obstructed, usually due to a dirty air filter, the furnace has to work harder to push the air through the system.   If there is a faulty thermostat sending inaccurate readings to the furnace causing it to short cycle, the furnace may overheat. Short cycling is identified when the furnace, heat pump or air conditioner starts and stops before it completes its heating or cooling cycle.   This symptom has a variety of causes but also creates a potential for overheating and a cracked heat exchanger.  

Risks of a Cracked Heat Exchanger

If the heat exchanger overheats to an extreme degree, there is a risk of fire. The more likely risk is carbon monoxide poisoning.   Carbon monoxide (CO) is an odorless, colorless gas which causes people to feel ill. Extreme exposure is lethal. When there’s a cracked heat exchanger in a home, the gases created by the combustion process leak into the indoor air.   Normally these gases exhaust outdoors unless they escape through the cracks in the heat exchanger.  

Avoid a Cracked Heat Exchanger with Furnace Experts through AC Southeast®

So, if you suspect you may have a cracked heat exchanger we’re here to help. If you haven’t had an HVAC tune-up in a while, it’s a great idea. Tune-ups include a thorough inspection with special camera equipment to confirm the integrity of the heat exchanger.   In addition to the benefits to your heating and cooling system, it will provide peace of mind. AC Southeast® can help match you with a local professional who can schedule a convenient time to perform a comprehensive inspection of your system.   We only work with trained and certified professionals who provide outstanding customer service. When you choose AC Southeast®, you are guaranteed a certified, trained professional will work on your furnace and if necessary, replace your cracked heat exchanger.