Cracked Heat Exchanger: What That Means and What You Should Do Next

September 20, 2022

A furnace is usually a background player in your home, keeping you warm during the cold winter months. It regularly doesn’t get noticed until something goes wrong.

One root cause could be that your furnace has a cracked heat exchanger. It’s a potentially dangerous issue, so it’s important to familiarize yourself with the symptoms of a cracked heat exchanger and what you should do if you believe that may be the problem.

What Is a Heat Exchanger in a Furnace?

A heat exchanger helps transition heat from the combustion chamber of your furnace to the air that moves through the ventilation. It generally does this via coils or tubes that heat the air while acting as a barrier to keep the gasses created in the combustion chamber, called flue gasses, from getting out into your home.

Is a Cracked Heat Exchanger Dangerous?

Given its central role, it isn't surprising that a cracked heat exchanger can pose a risk. A crack in the heat exchanger can allow dangerous gasses – such as carbon monoxide, which can be lethal – to be distributed through your home.

For this reason, don't ever turn on your heating if you believe there's a crack in the heat exchanger, as this could make the whole family sick. Call an HVAC professional immediately if you think your heating has a cracked heat exchanger that should be repaired.

Four Warning Signs of a Cracked Heat Exchanger:

  • Furnace switches off: Cracks in the heat exchanger could cause your furnace to turn off.
  • Odd Smells: If the air leaving your furnace has a powerful chemical odor, it could be a sign gas is slipping through cracks in your heat exchanger. These byproducts, which may smell like formaldehyde, are a significant warning sign.
  • Carbon monoxide alarm is triggered or you notice symptoms of poisoning: If a cracked heat exchanger is emitting carbon monoxide into your home, your carbon monoxide alarm may go off or household members might experience signs of carbon monoxide poisoning. Symptoms include headaches, dizziness, weakness, nausea, vomiting or feeling tired. If your alarm goes off or you feel sick, leave the home right away and then call for help.
  • Soot: If you spot black sooty accumulating on the exterior of your furnace, it’s an indication something may be seriously wrong.

What to Do if Your Furnace Heat Exchanger is Cracked

If you believe your furnace has a cracked heat exchanger, call a professional with extensive experience in furnace installation Naples as soon as possible so they can inspect your system and, if required, perform a furnace heat exchanger replacement. Costs often vary depending on the situation, but estimates can roughly suggest $1,000 to $3,000.

However, the good news is that heat exchangers are generally covered by the warranty. You should review the warranty paperwork on your furnace, since while the warranty might not cover the entire cost of repairs, it can significantly shrink your bill.

How to Prevent a Cracked Heat Exchanger in Your Home

One of the best ways to avoid problems in your furnace overall is with regular furnace maintenance. Furnaces provide the best possible return on investment when they run efficiently. Calling a trained professional to inspect your furnace for worn-out 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 inspect your furnace filters every few months – it’s recommended some filters be swapped out every 90 days or sooner if they are dirty or grimy. While the filters are not part of the heat exchanger itself, the strain of pulling air through a clogged filter makes your entire furnace work longer to do its job. And the harder your furnace works, the more wear and tear pieces like the heat exchanger will experience.