Cracked Heat Exchanger: What It Means and What You can Do Next

September 20, 2022

A furnace is almost always a background player in your home, ensuring you're warm in the cold winter months. It frequently doesn’t get noticed until a malfunction appears.

One root cause might be that your furnace has a cracked heat exchanger. It can potentially be hazardous, so it’s worthwhile to learn the signs of a cracked heat exchanger and what you should do if you suspect that is the problem.

What Is a Heat Exchanger in a Furnace?

A heat exchanger helps transition heat from the combustion chamber in your furnace to the air that moves through the air ducts. It usually does this through coils or tubes that warm the air while functioning as a barrier to keep the gasses formed in the combustion chamber, called flue gasses, from leaking out into your home.

Is a Cracked Heat Exchanger Dangerous?

Because of its important role, it isn't surprising that a damaged heat exchanger can pose a risk. Cracks in the heat exchanger can permit dangerous gasses – including carbon monoxide, which can be lethal – to flow throughout your home.

For this reason, never run your furnace if you believe there's a crack in the heat exchanger, as this could make your entire family sick. Reach out to an HVAC professional immediately if you think your heater has a cracked heat exchanger that needs to be repaired.

Four Signs of a Cracked Heat Exchanger:

  • Furnace shuts off: A crack in your heat exchanger may cause your furnace to switch off.
  • Strange Smells: If the air coming out of your furnace has an intense chemical smell, it might be an indicator that gas is seeping through cracks in your heat exchanger. These byproducts, which can smell like formaldehyde, are a significant warning sign.
  • Carbon monoxide alarm goes off or you notice poisoning symptoms: If a cracked heat exchanger is relieving carbon monoxide in your home, your carbon monoxide alarm should go off or household members might start experiencing signs of carbon monoxide poisoning. Complications include headaches, dizziness, weakness, nausea, vomiting or feeling tired. If your alarm goes off or you feel unwell, leave the home right away and then call for help.
  • Soot: If you notice black sooty accumulating around the exterior of your furnace, it’s an indication something could be seriously wrong.

What You Can Do if the Furnace Heat Exchanger is Cracked

If you suspect your furnace has a cracked heat exchanger, contact a professional with extensive experience in furnace installation Northglenn as soon as possible so they can inspect your system and, if necessary, handle a furnace heat exchanger replacement. Costs will fluctuate depending on the situation, but estimates can roughly suggest $1,000 to $3,000.

However, the good news is that heat exchangers are regularly covered by the warranty. It's a good idea to check the warranty paperwork on your furnace, since while the warranty won't always cover the entire cost of repairs, it could significantly lower your bill.

How to Prevent a Cracked Heat Exchanger in Your Home

One of the best ways to prevent a problem in your furnace overall is through regular furnace maintenance. Furnaces provide the best possible return on investment when they run efficiently. Hiring a certified professional to examine your furnace for worn-out parts, dirty filters and other common problems can keep you from getting a big bill later on.

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