Every year, carbon monoxide poisoning sends about 50,000 Americans to the emergency room and kills over 400. Many of these incidents involve home heating equipment.

The good news: CO poisoning is preventable. Understanding how it happens and taking simple precautions can protect your family.

🚨 If Your CO Detector Goes Off

  1. Don't ignore it—assume it's real
  2. Get everyone out of the house immediately
  3. Call 911 from outside
  4. Don't go back inside until emergency responders say it's safe
  5. Seek medical attention if anyone has symptoms

What Is Carbon Monoxide?

Carbon monoxide (CO) is a gas produced when fuels like natural gas, oil, propane, or wood don't burn completely. It's produced by:

  • Gas and oil furnaces
  • Water heaters
  • Gas stoves and ovens
  • Fireplaces and wood stoves
  • Car engines
  • Generators

When these appliances work properly and are well-vented, CO is safely exhausted outside. Problems occur when there's a malfunction or ventilation issue.

How Furnaces Can Produce Carbon Monoxide

Your gas furnace combusts fuel to create heat. The byproducts—including CO—are supposed to exit through the flue (exhaust vent). CO can enter your home if:

  • The heat exchanger is cracked. This is the most serious issue. Cracks allow combustion gases to leak into the air that circulates through your home.
  • The flue is blocked or damaged. Bird nests, debris, or corrosion can prevent proper venting.
  • Improper combustion. Dirty burners, incorrect gas pressure, or inadequate airflow can cause incomplete combustion.
  • Negative pressure. Exhaust fans, dryers, or a too-tight home can pull exhaust gases back inside.

⚠️ Warning Signs of a CO Problem

  • Yellow or orange furnace flame (should be blue)
  • Soot or scorch marks around the furnace
  • Excessive moisture on windows
  • Rust on flue pipes or appliance vents
  • Burning smell or unusual odors when furnace runs
  • Furnace struggles to stay lit

Symptoms of Carbon Monoxide Poisoning

CO symptoms are often mistaken for flu—which is especially dangerous in winter when both furnace use and flu season overlap.

Early symptoms:

  • Headache
  • Dizziness
  • Nausea
  • Fatigue
  • Shortness of breath

Severe symptoms:

  • Confusion
  • Vomiting
  • Loss of consciousness
  • Death

Key difference from flu: CO symptoms improve when you leave the house and return when you come back. If everyone in the household feels sick at the same time, especially pets, suspect CO.

How to Protect Your Family

1. Install CO Detectors

This is non-negotiable if you have gas appliances. Place detectors:

  • On every floor of your home
  • Near sleeping areas
  • Near attached garages
  • At least 15 feet from fuel-burning appliances (to avoid false alarms)

Test detectors monthly and replace batteries annually. Replace the entire unit every 5-7 years (check manufacturer recommendations).

đź’ˇ Combination Detectors

You can buy combo smoke/CO detectors that handle both in one unit. Make sure any detector you buy is UL-listed.

2. Schedule Annual Furnace Maintenance

Professional maintenance includes safety checks that can detect CO risks before they become dangerous:

  • Heat exchanger inspection for cracks
  • Flue and venting inspection
  • Combustion analysis
  • Carbon monoxide testing
  • Burner cleaning and adjustment

This is the single most important thing you can do to prevent furnace-related CO problems.

3. Never Block Vents or Flues

Make sure your furnace and water heater have adequate airflow. Don't store items near them or block air intakes.

4. Know the Age of Your Furnace

Heat exchangers are more likely to crack in older furnaces, especially those over 15-20 years old. If your furnace is aging, more frequent inspections are wise.

5. Never Use Unvented Heating Sources

Don't use your gas oven to heat your home. Never run generators, grills, or camp stoves indoors. These produce massive amounts of CO.

What Happens During a Safety Inspection

When we perform furnace maintenance, here's what we check for CO safety:

  • Visual heat exchanger inspection: Looking for cracks, rust, or corrosion
  • Combustion analysis: Measuring CO levels in the exhaust to ensure proper combustion
  • Flue inspection: Checking for blockages, proper slope, and secure connections
  • Draft testing: Ensuring combustion gases flow up and out properly
  • Ambient CO testing: Checking CO levels in the air around the furnace

If we find any safety issues, we'll explain exactly what's wrong and what needs to happen to fix it.

The Bottom Line

Carbon monoxide is a serious risk, but it's a manageable one. Install CO detectors, schedule annual furnace maintenance, and know the warning signs. These simple steps protect your family from an invisible danger.

If you can't remember the last time your furnace was inspected, or if you've noticed any warning signs, don't wait. Give us a call—your family's safety is worth it.