Can HVAC systems cause carbon monoxide in Colorado Springs homes?

Yes, gas furnaces can cause CO leaks if the heat exchanger cracks. This occurs in an estimated 15-20% of furnaces over 15 years old. The cracking happens due to thermal cycling — the furnace heating and cooling thousands of times over its lifespan, causing metal fatigue.

How often should I replace my CO detector in Colorado Springs?

Replace CO detector batteries annually and the sensor itself every 5-7 years regardless of battery life. Colorado recommends placing at least one detector on every level of your home, with the most critical placement within 15 feet of sleeping areas.

What are the signs of carbon monoxide poisoning vs. the flu?

CO poisoning causes headache, nausea, dizziness, and fatigue — similar to flu. The key difference: flu causes fever, but CO poisoning does not. If everyone in the house feels sick, symptoms improve when you leave, and there's no fever, CO exposure should be ruled out immediately.

How does Colorado Springs elevation affect furnace safety?

Colorado Springs sits at 6,035 feet elevation where thinner air affects combustion. Furnaces must be properly rated and tuned for altitude to operate safely. Technicians familiar with Springs installations know to check altitude compliance; those from lower elevations may not.

Can HVAC Cause Carbon Monoxide? What Colorado Homeowners Need to Know

Gas furnaces in Colorado Springs can produce carbon monoxide if the heat exchanger cracks, affecting an estimated 15-20% of furnaces over 15 years old — making annual inspections critical for safety.

Key Takeaways

Heat exchangers crack after thousands of thermal cycles; CO detectors should be replaced every 5-7 years

Colorado Springs sits at 6,035 feet elevation, requiring altitude-rated furnace tuning for proper combustion

CO poisoning mimics flu symptoms but lacks fever; pet illness alongside human symptoms signals CO exposure risk

Place CO detectors within 15 feet of sleeping areas on every home level for maximum protection

How does a gas furnace produce carbon monoxide?

Every gas furnace burns fuel to produce heat. That combustion creates carbon monoxide as a byproduct. In a properly working system, a component called the heat exchanger keeps combustion gases separated from the air that circulates through your home. The CO goes out the flue. You never know it was there.

The problem starts when the heat exchanger cracks.

Heat exchangers are metal. They heat up and cool down thousands of times over the life of the furnace. Over years, that thermal cycling causes metal fatigue. Cracks develop. When that happens, CO from the combustion chamber can pass through the crack and mix with the air your blower is pushing into your ductwork — and from there, into every room of your home.

What are the signs your heat exchanger might be cracked?

Some are obvious, some aren't:

The furnace flame is yellow or orange instead of blue
You notice a strong, chemical-like smell when the heat runs
There's visible soot buildup inside the furnace cabinet
Your CO detector is alarming
People in the house have unexplained headaches, dizziness, or nausea

That last set of symptoms is where it gets tricky.

How do you tell the difference between CO symptoms and the flu?

Carbon monoxide poisoning symptoms look a lot like the flu — headache, nausea, fatigue, dizziness. The key difference is that flu causes a fever. CO poisoning does not. If everyone in the house feels sick, symptoms improve when you leave, and there's no fever, CO exposure is worth ruling out.

Another tell: pets get sick too. Carbon monoxide affects animals the same as humans.

Where should you place CO detectors in your home?

A working CO detector is your best protection. Colorado recommends one on every level of the home. The most important placement is within 15 feet of sleeping areas, so it wakes you up if CO levels rise at night. Don't put detectors inside the garage — vehicle exhaust will trigger constant false alarms.

Replace detector batteries annually. Most CO detectors have a 5-7 year lifespan on the sensor itself regardless of battery life — check the manufacture date on the back.

Colorado Altitude Note

At 6,035 feet, Colorado Springs sits at a meaningful elevation. Thinner air at altitude affects combustion — furnaces have to work slightly differently than they do at sea level. This isn't a major risk on its own, but it does mean your furnace should be properly rated and tuned for altitude. A tech who works in the Springs knows to check this. One from the Front Range flatlands might not.

Why is an annual furnace inspection important for CO safety?

A cracked heat exchanger doesn't always show obvious symptoms before CO starts leaking. That's what makes annual inspections matter. A professional inspection includes a combustion analysis and visual inspection of the heat exchanger. Catching a crack early means you get it repaired or the furnace replaced before it becomes a CO event.

If your furnace is more than 15 years old, inspections are especially important. Heat exchanger cracks are far more common in aging systems.

What should you do if your CO alarm goes off?

Get everyone out of the house immediately — don't stop to grab anything
Leave the door open as you exit
Call 911 from outside or a neighbor's phone
Do not go back inside until emergency services have cleared the building

Don't assume a CO alarm is a false positive. Treat it as real until proven otherwise.

Get Your Furnace Inspected

If you haven't had a furnace inspection this season, or if your furnace is older and you've been putting it off, it's worth scheduling one. Our furnace repair page covers what a full furnace inspection includes, and we serve Colorado Springs and the surrounding areas.