The Importance of Carbon Monoxide Testing with Furnace Use in Minnesota Homes

As Minnesota temperatures drop and furnaces roar back to life, one invisible danger deserves every homeowner’s attention — carbon monoxide (CO). It’s colorless, odorless, and deadly — and every fall, cases of CO leaks spike across the state as heating systems kick on after months of dormancy.

Why Carbon Monoxide Testing Matters
Carbon monoxide is produced anytime fuel burns — natural gas, propane, oil, or wood. When your furnace is properly vented and maintained, CO is safely expelled outside.

But even a small crack in a heat exchanger, a blocked vent, or poor combustion can leak CO directly into your living space.

According to the Minnesota Department of Health, hundreds of residents experience CO poisoning each year — most often in fall and winter. The signs can start subtle:

• Dull headaches
• Dizziness
• Nausea
• Shortness of breath

And because symptoms mimic the flu, many people don’t realize what’s happening until it’s serious.

How Often Should You Test for Carbon Monoxide?

​CO testing should be part of your annual furnace inspection — ideally before the first long stretch of heating season. A professional HVAC technician uses calibrated instruments to measure CO levels and inspect components that could cause leaks, including:

• Heat exchangers
• Burners and pilot assemblies
• Flue and vent systems
• Draft inducers and exhaust fans

Even if your furnace is newer, yearly testing ensures that small issues don’t grow into major hazards.

Do Carbon Monoxide Detectors Replace Professional Testing? Short answer: no — they complement it.
A CO detector alerts you to a leak, but it doesn’t prevent one. Think of detectors like smoke alarms: essential, but reactive. To truly protect your home, pair your detector system with proactive HVAC maintenance and CO testing each fall. Minnesota law requires CO detectors in every home with fuel-burning appliances or attached garages — ideally placed near sleeping areas and each floor level.

Common Causes of Carbon Monoxide Leaks in Furnaces

1. Cracked heat exchanger – Often due to age or corrosion.
2. Blocked exhaust or vent pipe – Caused by leaves, snow, or ice.
3. Incomplete combustion – Dirty burners or incorrect air/fuel mixture.
4. Improper installation – Incorrect venting angles or undersized flue pipes.

Even the best equipment can fail if not maintained — which is why professional inspection is critical before Minnesota’s first deep freeze.

The Air Comfort MN Difference

At Air Comfort Heating & Air Conditioning, safety isn’t an afterthought — it’s the foundation of what we do.
Our certified technicians perform comprehensive CO testing and furnace safety checks for families across Anoka County and beyond. We ensure your system runs cleanly, efficiently, and safely — all season long.

📞 Call (763) 753-6623 to schedule your furnace safety inspection before winter settles in.