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

September 20, 2022

A furnace is often a background player in your home, keeping you warm during the cold winter months. It frequently won't be noticed until something goes wrong.

One cause may be that your furnace has a cracked heat exchanger. It can potentially be hazardous, so it’s important to know the signs of a cracked heat exchanger and what you should do if you believe that is the problem.

What Is a Heat Exchanger in a Furnace?

A heat exchanger transfers heat from the combustion chamber of your furnace to the air that circulates inside the ventilation. It typically handles this with coils or tubes that warm the air while functioning 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?

Because of its key role, it isn't surprising that a cracked heat exchanger can pose a risk. A damaged heat exchanger can allow dangerous gasses – like carbon monoxide, which can be lethal – to flow across your home.

For this reason, never run your heating if you think it has a cracked heat exchanger, as letting it run could make the entire family sick. Reach out to an HVAC professional right away if you believe your furnace has a cracked heat exchanger that should be repaired.

Four Symptoms of a Cracked Heat Exchanger:

  • Furnace shuts off: A cracked heat exchanger can cause your furnace to switch off.
  • Strange Smells: If the air escaping your furnace has a strong chemical smell, it might be a sign gasses are slipping through cracks in your heat exchanger. These byproducts, which may smell like formaldehyde, are a major warning sign.
  • Carbon monoxide alarm initiates or you feel health problems: If a cracked heat exchanger is emitting carbon monoxide inside your home, your carbon monoxide alarm may go off or household members may experience signs of carbon monoxide poisoning. Complications include headaches, dizziness, weakness, nausea, vomiting or feeling drowsy. If your alarm goes off or you feel sick, leave the home as soon as you can and then call for help.
  • Soot: If you notice black sooty accumulating on the exterior of your furnace, it’s an indication something might be seriously wrong.

What You Should Do if Your Furnace Heat Exchanger is Cracked

If you worry your furnace has a cracked heat exchanger, contact a professional experienced in furnace installation Chadron as soon as possible so they can take a look at your system and, if required, handle a furnace heat exchanger replacement. Costs often vary depending on the situation, but estimates run in the neighborhood of $1,000 to $3,000.

However, the good news is that heat exchangers are regularly protected by the warranty. You’ll want to confirm the warranty paperwork on your furnace, because while the warranty might not cover the entire cost of repairs, it could significantly reduce 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 consistent furnace maintenance. Furnaces work the best when they run efficiently. Contacting a certified professional to inspect your furnace for worn-out parts, dirty filters and other potential problems can keep you from getting a big bill later on.

It’s also beneficial to inspect 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 connected to the heat exchanger itself, the strain of pulling air through a clogged filter makes the entire furnace work longer to do its job. And the harder your furnace works, the more deterioration parts like the heat exchanger will sustain.