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

September 20, 2022

A furnace is almost always a background player at home, keeping you warm in the cold winter months. It frequently won't be noticed until something breaks down.

One root cause might be that your furnace has a cracked heat exchanger. It can be a safety risk, so it’s worthwhile to know the evidence of a cracked heat exchanger and what you can 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 flows inside the ventilation. It usually accomplishes this via coils or tubes that heat up the air while acting as a barrier to keep gas created in the combustion chamber, called flue gasses, from escaping out into your home.

Is a Cracked Heat Exchanger Dangerous?

Given its key role, it isn't surprising that a broken heat exchanger can be hazardous. A damaged heat exchanger can enable dangerous gasses – including carbon monoxide, which can be lethal – to flow throughout your home.

For this reason, don't ever turn on your heating if you suspect you're dealing with a cracked heat exchanger, as doing so could make your entire family ill. Reach out to an HVAC professional right away if you think your furnace has a cracked heat exchanger that should be repaired.

Four Signs of a Cracked Heat Exchanger:

  • Furnace shuts off: A cracked heat exchanger could cause your furnace to turn off.
  • Strange Smells: If the air leaving your furnace has an intense chemical odor, it might be evidence gas is slipping through cracks in your heat exchanger. These gasses, which will often smell like formaldehyde, are a common warning sign.
  • Carbon monoxide alarm goes off or you feel health problems: If a cracked heat exchanger is releasing carbon monoxide inside your home, your carbon monoxide alarm should go off or household members might start experiencing signs of carbon monoxide poisoning. Complications include headaches, dizziness, weakness, nausea, vomiting or feeling tired. If the alarm goes off or you feel unusually tired, exit the home immediately and then call for help.
  • Soot: If you notice black sooty accumulating on the exterior of your furnace, it’s more evidence something could be seriously wrong.

What You Should Do if a Furnace Heat Exchanger is Cracked

If you suspect your furnace has a cracked heat exchanger, hire a professional with extensive experience in furnace installation Hudsonville right away so they can inspect your system and, if necessary, start a furnace heat exchanger replacement. Costs often vary depending on the situation, but estimates often hover around $1,000 to $3,000.

However, the good news is that heat exchangers are regularly included in 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 still may 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 with consistent furnace maintenance. Furnaces provide the best possible return on investment when they work efficiently. Hiring a certified professional to examine your furnace for old parts, clogs in the air filters and other potential problems can keep you from getting a big bill later on.

It’s also a good idea to inspect 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 aren't a part of 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 needs to run, the more strain parts like the heat exchanger will endure.