A furnace is almost always a background player in your home, helping keep you warm in the cold winter months. It regularly won't be noticed until a malfunction appears.
One source may be that your furnace has a cracked heat exchanger. It’s a potentially dangerous issue, so it’s worthwhile to know the signs of a cracked heat exchanger and what you should do if you suspect 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 circulates inside the air ducts. It usually handles this via coils or tubes that heat up the air while acting as a barrier to keep byproducts formed in the combustion chamber, called flue gasses, from leaking out into your home.
Is a Cracked Heat Exchanger Dangerous?
Because of its central role, it isn't surprising that a broken heat exchanger can be hazardous. Cracks in the heat exchanger can enable dangerous gasses – including carbon monoxide, which can be lethal – to circulate across your home.
For obvious reasons, do NOT run your furnace if you believe you're dealing with a cracked heat exchanger, as this could make the entire family ill. Reach out to an HVAC professional immediately if you are worried your heating has a cracked heat exchanger that needs repair.
Four Signs of a Cracked Heat Exchanger:
- Furnace turns off: Cracks in the heat exchanger could cause your furnace to shut off.
- Unusual Smells: If the air leaving your furnace has a powerful chemical scent, it may be an indicator that 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 feel poisoning symptoms: If a cracked heat exchanger is releasing carbon monoxide inside your home, your carbon monoxide alarm could go off or household members may start experiencing signs of carbon monoxide poisoning. Symptoms include headaches, dizziness, weakness, nausea, vomiting or feeling drowsy. If the alarm goes off or you feel unwell, leave the home right away and then call for help.
- Soot: If you see black sooty buildup near the exterior of your furnace, it’s more evidence something might be seriously wrong.
What You Should Do if the Furnace Heat Exchanger is Cracked
If you worry your furnace has a cracked heat exchanger, hire a professional with extensive experience in furnace installation Menomonie and western Wisconsin right away so they can inspect your system and, if needed, perform a furnace heat exchanger replacement. Costs often differ depending on the situation, but estimates can roughly suggest $1,000 to $3,000.
However, the good news is that heat exchangers are regularly covered by the warranty. You should confirm the warranty paperwork on your furnace, since while the warranty might not cover the entire cost of repairs, it can significantly lower your bill.
How to Avoid a Cracked Heat Exchanger in Your Home
One of the best ways to avoid problems in your furnace overall is via regular furnace maintenance. Furnaces offer the most benefits when they operate efficiently. Contacting a certified professional to examine your furnace for worn-out parts, clogs in the air filters and other potential 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 recommended some filters be replaced every 90 days or sooner if they are dirty or grimy. While the filters aren't connected to 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 has to work, the more deterioration parts like the heat exchanger will endure.