A furnace is often a background player for your home, helping keep you warm during the cold winter months. It often won't be 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 may be 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 moves inside the air ducts. It typically does this using coils or tubes that heat the air while serving as a barrier to keep gas produced in the combustion chamber, called flue gasses, from leaking out into your home.  

Is a Cracked Heat Exchanger Dangerous? 

Given its central role, it’s no surprise that a cracked heat exchanger can pose a risk. A crack in the heat exchanger can allow dangerous gasses – like carbon monoxide, which can be lethal – to flow across your home. 

For obvious reasons, never use your heater if you suspect you're dealing with a cracked heat exchanger, as letting it run could make the entire household sick. Reach out to an HVAC professional as soon as possible if you believe your heating has a cracked heat exchanger that needs repair. 

Four Symptoms of a Cracked Heat Exchanger: 

  • Furnace shuts off: A cracked heat exchanger could cause your furnace to turn off. 
  • Odd Smells: If the air coming out of your furnace has an intense chemical odor, it might be a sign gasses are slipping through cracks in your heat exchanger. These gasses, which may smell like formaldehyde, are a significant 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 may go off or family members could experience signs of carbon monoxide poisoning. Side effects include headaches, dizziness, weakness, nausea, vomiting or feeling sleepy. If your alarm goes off or you feel unwell, leave the home right away and then call for help. 
  • Soot: If you spot black sooty buildup around the exterior of your furnace, it’s an indication something may be seriously wrong.

What to Do if Your Furnace Heat Exchanger is Cracked 

If you worry your furnace has a cracked heat exchanger, call a professional well versed in furnace installation Moline right away so they can inspect your system and, if required, perform a furnace heat exchanger replacement. Costs will fluctuate depending on the situation, but estimates can roughly suggest $1,000 to $3,000. 

Estimates aside, the good news is that heat exchangers are regularly included in the warranty. You should confirm the warranty paperwork on your furnace, since 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 most convenient ways to prevent a problem in your furnace overall is via consistent furnace maintenance. Furnaces offer the most benefits when they operate efficiently. Contacting a certified professional to check 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 helpful to inspect your furnace filters every few months – it’s recommended 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 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 deterioration pieces like the heat exchanger will sustain.