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

September 20, 2022

A furnace is often a background player for your home, helping keep you warm during the cold winter months. It often isn't noticed until something goes wrong.

One source could be that your furnace has a cracked heat exchanger. It can potentially be hazardous, so it’s critical to know the evidence of a cracked heat exchanger and what you should do if you are worried that is 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 circulates through the system. It usually handles this using coils or tubes that heat up the air while functioning as a barrier to keep gas produced in the combustion chamber, called flue gasses, from getting out into your home.

Is a Cracked Heat Exchanger Dangerous?

Given its key role, it shouldn't come as a surprise that a broken heat exchanger can be very dangerous. A damaged heat exchanger can enable dangerous gasses – such as carbon monoxide, which can be lethal – to circulate throughout your home.

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

Four Signs of a Cracked Heat Exchanger:

  • Furnace switches off: A crack in your heat exchanger could cause your furnace to switch off.
  • Unusual Smells: If the air leaving your furnace has a powerful chemical odor, it may be a sign gasses are slipping through cracks in your heat exchanger. These gasses, which can smell like formaldehyde, are a major warning sign.
  • Carbon monoxide alarm goes off or you recognize symptoms of poisoning: If a cracked heat exchanger is releasing carbon monoxide into your home, your carbon monoxide alarm should go off or family members could struggle with signs of carbon monoxide poisoning. Side effects include headaches, dizziness, weakness, nausea, vomiting or feeling drowsy. If an alarm goes off or you feel unusually tired, get out of the home as soon as you can and then call for help.
  • Soot: If you find black sooty buildup on the exterior of your furnace, it’s more evidence something may be seriously wrong.

What You Should Do if Your Furnace Heat Exchanger is Cracked

If you worry your furnace has a cracked heat exchanger, hire a professional experienced in furnace installation Bartlesville as soon as possible so they can take a look at your system and, if necessary, perform a furnace heat exchanger replacement. Costs should 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 generally covered by the warranty. You’ll want to confirm the warranty paperwork on your furnace, as while the warranty might not cover the entire cost of repairs, it could significantly reduce 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 via regular furnace maintenance. Furnaces work the best when they work efficiently. Contacting a certified professional to inspect your furnace for worn-out parts, dirty filters and other common problems can help you avoid getting a big bill later on.

It’s also helpful to review your furnace filters every few months – it’s encouraged some filters be changed 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 dragging air through a clogged filter makes your entire furnace work harder to do its job. And the harder your furnace has to work, the more wear and tear parts like the heat exchanger will sustain.