
A furnace is almost always a background player at home, keeping you warm in the cold winter months. It frequently isn't noticed until a malfunction appears.
One root cause might 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 can do if you are worried that might 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 through the air ducts. It generally does this through coils or tubes that warm the air while acting as a barrier to keep byproducts created 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 shouldn't come as a surprise that a broken heat exchanger can be hazardous. Cracks in the heat exchanger can permit dangerous gasses – including carbon monoxide, which can be lethal – to circulate across your home.
For that reason, do NOT run your furnace if you suspect you're dealing with a cracked heat exchanger, as this could make the whole household sick. Reach out to an HVAC professional immediately if you think your furnace has a cracked heat exchanger that needs to be repaired.
Four Signs of a Cracked Heat Exchanger:
- Furnace switches off: A crack in your heat exchanger may cause your furnace to turn off.
- Odd Smells: If the air leaving your furnace has a strong chemical scent, it might be an indicator that gasses are leaking through cracks in your heat exchanger. These byproducts, which will often smell like formaldehyde, are a major warning sign.
- Carbon monoxide alarm initiates or you recognize health problems: If a cracked heat exchanger is emitting carbon monoxide into your home, your carbon monoxide alarm could go off or family members may struggle with signs of carbon monoxide poisoning. Complications include headaches, dizziness, weakness, nausea, vomiting or feeling drowsy. If the alarm goes off or you feel unusually tired, get out of the home as soon as you can and then call for help.
- Soot: If you find black sooty buildup near the exterior of your furnace, it’s more evidence something may be seriously wrong.
What to Do if a Furnace Heat Exchanger is Cracked
If you worry your furnace has a cracked heat exchanger, hire a pro well versed in furnace installation Manassas as soon as possible so they can inspect your system and, if necessary, handle a furnace heat exchanger replacement. Costs will fluctuate depending on the situation, but estimates can roughly suggest $1,000 to $3,000.
However, the good news is that heat exchangers are regularly protected by the warranty. It's a good idea to review the warranty paperwork on your furnace, as while the warranty won't always cover the entire cost of repairs, it could significantly lower your bill.
How to Avoid a Cracked Heat Exchanger in Your Home
One of the most convenient ways to minimize the risk of problems in your furnace overall is with routine furnace maintenance. Furnaces offer the most benefits when they work efficiently. Calling a trained professional to check your furnace for old parts, dirty filters and other potential problems can help you avoid getting a big bill later on.
It’s also helpful to inspect your furnace filters every few months – it’s ideal some filters be swapped out 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 dragging air through a clogged filter makes your entire furnace work longer to do its job. And the harder your furnace works, the more deterioration components like the heat exchanger will experience.