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

September 20, 2022

A furnace is almost always a background player at home, ensuring you're warm in the cold winter months. It often doesn’t get noticed until something goes wrong.

One root cause could be that your furnace has a cracked heat exchanger. It can potentially be hazardous, so it’s critical to familiarize yourself with the signs of a cracked heat exchanger and what to do if you believe that is the problem.

What Is a Heat Exchanger in a Furnace?

A heat exchanger helps move heat from the combustion chamber in your furnace to the air that moves throughout the ventilation. It typically does this through coils or tubes that warm the air while serving 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?

Thanks to its important role, it isn't surprising that a cracked heat exchanger can be very dangerous. Cracks in the heat exchanger can enable dangerous gasses – like carbon monoxide, which can be lethal – to circulate throughout your home.

For this reason, do NOT use your heating if you suspect you're dealing with a cracked heat exchanger, as doing so could make the whole family ill. Call an HVAC professional immediately if you believe your furnace has a cracked heat exchanger that needs repair.

Four Symptoms of a Cracked Heat Exchanger:

  • Furnace turns off: A cracked heat exchanger can cause your furnace to shut off.
  • Strange Smells: If the air coming out of your furnace has an intense chemical smell, it could be a sign gasses are seeping through cracks in your heat exchanger. These gasses, which will often smell like formaldehyde, are a significant warning sign.
  • Carbon monoxide alarm initiates or you notice poisoning symptoms: If a cracked heat exchanger is relieving carbon monoxide into your home, your carbon monoxide alarm may go off or family members may struggle with signs of carbon monoxide poisoning. Side effects include headaches, dizziness, weakness, nausea, vomiting or feeling sleepy. If the alarm goes off or you feel unwell, leave the home immediately and then call for help.
  • Soot: If you see black sooty buildup on the exterior of your furnace, it’s more evidence something could be seriously wrong.

What You Can Do if Your Furnace Heat Exchanger is Cracked

If you believe your furnace has a cracked heat exchanger, contact a professional with extensive experience in furnace installation Genoa right away so they can inspect your system and, if needed, start a furnace heat exchanger replacement. Costs should 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 protected by the warranty. You’ll want to confirm the warranty paperwork on your furnace, since while the warranty may 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 easiest ways to avoid problems in your furnace overall is with consistent furnace maintenance. Furnaces work the best when they work efficiently. Contacting a certified professional to inspect your furnace for broken-down parts, dirty filters and other common problems can keep you from getting a big bill later on.

It’s also beneficial to take a look at 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 a part of the heat exchanger itself, the strain of drawing air through a clogged filter makes your entire furnace work harder to accomplish its job. And the harder your furnace needs to run, the more deterioration pieces like the heat exchanger will sustain.