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 cause may be that your furnace has a cracked heat exchanger. It can potentially be hazardous, so it’s critical to familiarize yourself with the signs of a cracked heat exchanger and what you can do if you are worried that may be 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 throughout the ventilation. It generally does this via coils or tubes that heat the air while serving as a barrier to keep the gasses produced in the combustion chamber, called flue gasses, from escaping out into your home.
Is a Cracked Heat Exchanger Dangerous?
Thanks to its central role, it’s no surprise that a cracked heat exchanger can be very dangerous. Cracks in the heat exchanger can allow dangerous gasses – like carbon monoxide, which can be lethal – to circulate throughout your home.
For this reason, do NOT turn on your heating if you believe it has a cracked heat exchanger, as doing so could make your entire household sick. Contact an HVAC professional immediately if you are worried your heater has a cracked heat exchanger that needs repair.
Four Symptoms of a Cracked Heat Exchanger:
- Furnace shuts off: A cracked heat exchanger may cause your furnace to switch off.
- Strange Smells: If the air leaving your furnace has an intense chemical smell, it could be an indicator that gasses are leaking through cracks in your heat exchanger. These byproducts, which can smell like formaldehyde, are a common warning sign.
- Carbon monoxide alarm goes off or you feel poisoning symptoms: If a cracked heat exchanger is emitting carbon monoxide inside your home, your carbon monoxide alarm could go off or household members could start experiencing signs of carbon monoxide poisoning. Side effects include headaches, dizziness, weakness, nausea, vomiting or feeling sleepy. If the alarm goes off or you feel unusually tired, get out of the home right away and then call for help.
- Soot: If you spot black sooty buildup on the exterior of your furnace, it’s another sign something might be seriously wrong.
What to Do if Your Furnace Heat Exchanger is Cracked
If you believe your furnace has a cracked heat exchanger, call a pro well versed in furnace installation Wisconsin Rapids as soon as possible so they can inspect your system and, if required, start a furnace heat exchanger replacement. Costs will vary depending on the situation, but estimates run in the neighborhood of $1,000 to $3,000.
Fortunately, the good news is that heat exchangers are regularly included in the warranty. You’ll want to review the warranty paperwork on your furnace, since while the warranty might not cover the entire cost of repairs, it still may significantly lower your bill.
How to Prevent a Cracked Heat Exchanger in Your Home
One of the easiest ways to avoid problems in your furnace overall is with routine furnace maintenance. Furnaces provide the best possible return on investment when they run efficiently. Calling a certified professional to examine your furnace for broken-down 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 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 aren't a part of the heat exchanger itself, the strain of dragging air through a clogged filter makes your entire furnace work harder to complete its job. And the harder your furnace has to work, the more strain components like the heat exchanger will experience.