A furnace is almost always a background player for your home, keeping you warm in the cold winter months. It frequently isn't noticed until something goes wrong. 

One root cause may be that your furnace has a cracked heat exchanger. It can be a safety risk, so it’s critical to know the symptoms of a cracked heat exchanger and what you can do if you are worried that is the problem.  

What Is a Heat Exchanger in a Furnace? 

A heat exchanger helps move heat from the combustion chamber of your furnace to the air that flows inside the ventilation. It usually handles this using coils or tubes that warm the air while functioning as a barrier to keep byproducts created in the combustion chamber, called flue gasses, from leaking out into your home.  

Is a Cracked Heat Exchanger Dangerous? 

Because of its key role, it’s no surprise that a damaged heat exchanger can be very dangerous. A crack in the heat exchanger can permit dangerous gasses – such as carbon monoxide, which can be lethal – to be distributed across your home. 

For this reason, don't ever use your heater if you think you're dealing with a cracked heat exchanger, as this could make the entire family ill. Contact an HVAC professional as soon as possible if you think your heating has a cracked heat exchanger that needs to be repaired. 

Four Symptoms of a Cracked Heat Exchanger: 

  • Furnace turns off: Cracks in the heat exchanger could cause your furnace to switch off. 
  • Unusual Smells: If the air coming out of your furnace has a strong chemical scent, it may be an indicator that gas is leaking through cracks in your heat exchanger. These byproducts, which will often smell like formaldehyde, are a major warning sign. 
  • Carbon monoxide alarm initiates or you notice health problems: If a cracked heat exchanger is emitting carbon monoxide in your home, your carbon monoxide alarm could go off or family members may experience signs of carbon monoxide poisoning. Symptoms include headaches, dizziness, weakness, nausea, vomiting or feeling tired. If the alarm goes off or you feel unwell, exit the home immediately and then call for help. 
  • Soot: If you find black sooty collecting on the exterior of your furnace, it’s an indication something may be seriously wrong.

What You Should Do if the Furnace Heat Exchanger is Cracked 

If you worry your furnace has a cracked heat exchanger, call a professional with extensive experience in furnace installation Chadron right away so they can take a look at your system and, if required, start a furnace heat exchanger replacement. Costs often fluctuate depending on the situation, but estimates run in the neighborhood of $1,000 to $3,000. 

Estimates aside, the good news is that heat exchangers are often covered by the warranty. You’ll want to review the warranty paperwork on your furnace, since while the warranty may not cover the entire cost of repairs, it could significantly shrink your bill.  

How to Avoid a Cracked Heat Exchanger in Your Home  

One of the easiest ways to avoid problems in your furnace overall is through routine furnace maintenance. Furnaces provide the best possible return on investment when they work efficiently. Contacting a trained professional to examine your furnace for broken-down parts, clogs in the air filters and other likely problems can help you avoid getting a big bill later on.  

It’s also a good idea to review your furnace filters every few months – it’s encouraged some filters be swapped out every 90 days or sooner if they are dirty or grimy. While the filters aren't connected to the heat exchanger itself, the strain of dragging air through a clogged filter makes the entire furnace work harder to accomplish its job. And the harder your furnace needs to run, the more wear and tear components like the heat exchanger will endure.