Cracked Heat Exchanger: What This Means and What to Do Next

September 20, 2022

A furnace is usually a background player at home, ensuring you're warm during the cold winter months. It frequently won't be noticed until something goes wrong.

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

What Is a Heat Exchanger in a Furnace?

A heat exchanger transfers heat from the combustion chamber inside your furnace to the air that circulates through the air ducts. It typically handles this through coils or tubes that heat the air while serving as a barrier to keep byproducts created in the combustion chamber, called flue gasses, from leaking out into your home.

Is a Cracked Heat Exchanger Dangerous?

Given its central role, it shouldn't come as a surprise that a damaged heat exchanger can be very dangerous. Cracks in the heat exchanger can enable dangerous gasses – like carbon monoxide, which can be lethal – to circulate through your home.

For obvious reasons, do NOT use your furnace if you think there's a crack in the heat exchanger, as letting it run could make the entire family ill. Reach out to an HVAC professional as soon as possible if you think your heating has a cracked heat exchanger that needs to be repaired.

Four Symptoms of a Cracked Heat Exchanger:

  • Furnace switches off: A crack in your heat exchanger can cause your furnace to turn off.
  • Unusual Smells: If the air leaving your furnace has a powerful chemical scent, it might be an indicator that gasses are leaking through cracks in your heat exchanger. These gasses, which can smell like formaldehyde, are a major warning sign.
  • Carbon monoxide alarm initiates or you recognize symptoms of poisoning: If a cracked heat exchanger is releasing carbon monoxide in your home, your carbon monoxide alarm may go off or household members might experience signs of carbon monoxide poisoning. Side effects include headaches, dizziness, weakness, nausea, vomiting or feeling drowsy. If your alarm goes off or you feel unusually tired, get out of the home immediately and then call for help.
  • Soot: If you find black sooty collecting near the exterior of your furnace, it’s more evidence something might be seriously wrong.

What to Do if Your Furnace Heat Exchanger is Cracked

If you suspect your furnace has a cracked heat exchanger, call a professional with extensive experience in furnace installation the Rio Grande Valley right away so they can examine your system and, if required, start a furnace heat exchanger replacement. Costs will differ 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 often covered by the warranty. You’ll want to review the warranty paperwork on your furnace, as 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 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 work efficiently. Hiring a skilled professional to examine your furnace for worn-out parts, clogs in the air filters and other common problems can help you avoid 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 replaced 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 harder to do its job. And the harder your furnace has to work, the more deterioration parts like the heat exchanger will sustain.