Carbon Monoxide: The Silent Killer I Keep Finding in Central and Northern Illinois Homes
Written by Chase Owen
In the past month alone, while inspecting homes across Peoria and Rockford, I have found three separate combustion exhausts in dangerous condition: open holes in a water heater exhaust pipe, a water heater exhaust that was completely disconnected, and a furnace exhaust venting directly into a basement. On top of that, I have walked through multiple homes with no working carbon monoxide detector anywhere on the property. Any one of these conditions can kill a family in their sleep, and the homeowners in every case had no idea.
I want to share what I am seeing in the field, why it matters, and what every homeowner can do this weekend to protect their family.
Why Carbon Monoxide Is Called the Silent Killer
Carbon monoxide is a colorless, odorless, tasteless gas produced anytime fuel burns incompletely. Furnaces, water heaters, gas stoves, fireplaces, generators, and even attached garages with a running car can all produce it. Because you cannot see it or smell it, the only warning most families ever get is the alarm of a working CO detector — assuming one is installed and the batteries are good.
The Centers for Disease Control and Prevention reports that each year, more than 400 Americans die from unintentional carbon monoxide poisoning not linked to fires, more than 100,000 visit an emergency department, and more than 14,000 are hospitalized. Many of those incidents trace back to exactly the kinds of installation failures I am finding during routine home inspections.
What I Am Finding in the Field
Three exhaust failures in one month is not normal, but it is not uncommon either. In Central and Northern Illinois, our combination of older housing stock, heavy winter heating loads, and decades of freeze-thaw stress on metal flues means combustion exhaust systems quietly degrade over time. A homeowner who has lived with the same furnace for fifteen years has no reason to climb into a crawl space and look at the joints — and that is exactly where the failure happens.
The disconnected water heater exhaust in the photo above is a textbook example. The galvanized vent pipe rusted through at the chimney connection. Once that joint failed, every minute the water heater fired, combustion gases poured into the crawl space instead of going up the chimney. The homeowner had no symptoms yet because the exposure was intermittent, but a long shower, a cold snap pushing the water heater harder, or a sealed-up crawl space hatch could have changed that fast.
The other two failures I found this month — open holes in a different water heater exhaust and a furnace exhaust completely open to the basement — were similarly invisible to the homeowners. Neither home had a CO detector anywhere near the mechanical room.
What Every Homeowner Should Do This Week
Install at least one carbon monoxide detector on every floor of your home, including the basement. Place one within ten feet of every bedroom door so an alarm at night will wake you. Most building codes in Illinois already require this, but compliance is uneven and many older homes were never updated.
Test the detectors you already have by pressing the test button. Replace the batteries if they have not been changed in the past year. Check the manufacture date printed on the back of the unit — CO detectors have a five-to-seven year sensor lifespan even if they still beep when tested. Anything older than that should be replaced regardless of how it sounds.
Have your furnace and water heater inspected annually by a qualified HVAC technician. Ask them specifically to check the exhaust venting from the appliance all the way to where it exits the home. Most annual service calls focus on the appliance itself; the venting is often skipped.
Finally, do not idle a vehicle in an attached garage even with the garage door open, do not run a generator inside any enclosed space, and do not use a gas stove or oven for heat.
When to Call for a Professional Inspection
If you are buying a home in Peoria, Rockford, or anywhere in Central or Northern Illinois, a professional home inspection should always include a thorough look at every combustion appliance and its venting. At Heart of Illinois Property Services, I personally inspect the furnace, water heater, fireplace, and any other gas-burning equipment in the home, including the crawl space and attic runs that most people never see. If something is wrong, you will know before you close.
If you already own your home and you have not had your combustion appliances and CO detectors evaluated recently, schedule it now. Do not wait for cold weather to make the problem urgent.
If you have any questions about carbon monoxide safety in your home, or you want a professional set of eyes on your furnace and water heater venting before winter, I am here to help.