A furnace is usually a background player for your home, keeping you warm during the cold winter months. It frequently doesn’t get noticed until something goes wrong.
One root cause might be that your furnace has a cracked heat exchanger. It can be a safety risk, so it’s critical to know 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 helps move heat from the combustion chamber in your furnace to the air that circulates through the air ducts. It usually handles this via coils or tubes that heat up the air while acting 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?
Because of its central role, it’s no surprise that a broken heat exchanger can be very dangerous. A damaged heat exchanger can allow dangerous gasses – including carbon monoxide, which can be lethal – to be distributed throughout your home.
For that reason, never turn on your heating if you suspect it has a cracked heat exchanger, as doing so could make the whole family ill. Reach out to an HVAC professional right away if you believe your heating has a cracked heat exchanger that should be repaired.
Four Symptoms of a Cracked Heat Exchanger:
- Furnace switches off: Cracks in the heat exchanger may cause your furnace to turn off.
- Odd Smells: If the air leaving your furnace has a powerful chemical odor, it may be an indicator that gasses are seeping 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 poisoning symptoms: If a cracked heat exchanger is emitting carbon monoxide in your home, your carbon monoxide alarm could go off or family members may struggle with signs of carbon monoxide poisoning. Side effects include headaches, dizziness, weakness, nausea, vomiting or feeling sleepy. If your alarm goes off or you feel sick, exit the home immediately and then call for help.
- Soot: If you spot black sooty buildup near the exterior of your furnace, it’s more evidence something could be seriously wrong.
What You Can Do if a Furnace Heat Exchanger is Cracked
If you suspect your furnace has a cracked heat exchanger, contact a professional with extensive experience in furnace installation as soon as possible so they can examine your system and, if needed, start a furnace heat exchanger replacement. Costs often vary depending on the situation, but estimates can roughly suggest $1,000 to $3,000.
Estimates aside, the good news is that heat exchangers are generally covered by the warranty. You should confirm the warranty paperwork on your furnace, as 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 most convenient ways to prevent a problem in your furnace overall is with consistent furnace maintenance. Furnaces work the best when they run efficiently. Calling a skilled professional to check your furnace for broken-down parts, dirty filters and other likely problems can help you avoid 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 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 drawing air through a clogged filter makes your entire furnace work more vigorously to do its job. And the harder your furnace works, the more strain components like the heat exchanger will experience.