Why carbon monoxide is dangerous

Carbon monoxide, often called CO, is a gas produced when fuel does not burn completely. You cannot see it or smell it, and at high levels it can make people seriously ill very quickly. Gas furnaces, water heaters, stoves, and fireplaces all burn fuel, which is why detectors and maintenance matter.

Warning signs to know

Early symptoms often feel like the flu without a fever. Pay attention if several people in the home feel unwell at the same time, or if symptoms fade when you leave the house.

• Headaches that come and go

• Dizziness or confusion

• Nausea or an upset stomach

• Tiredness and weakness

• Pets that seem unusually sluggish

What causes a leak

A properly working gas furnace sends its exhaust outside through a flue. Problems start when something interferes with that path or the burner itself.

• A cracked heat exchanger

• A blocked or damaged flue or vent

• A dirty or poorly adjusted burner

• Poor airflow caused by a clogged filter

How to protect your family

Detectors are your first line of defense, and a yearly furnace inspection is your best prevention.

1. Install CO detectors on every level and near sleeping areas.

2. Test them every month and replace them according to the manufacturer's schedule.

3. Have your furnace inspected every year before cold weather.

4. Keep vents and flues clear of leaves, nests, and snow or debris.

5. Never use an oven, grill, or portable fuel heater to warm your home.

What an inspection includes

Our technicians check the heat exchanger, burners, flue, ignition, airflow, and safety controls, and they test the air for carbon monoxide during the visit. You get a plain summary of what we found and what, if anything, needs attention.

If your alarm goes off

Treat every alarm as real. Get everyone, including pets, outside right away and call 911 from outside. Do not go back in until responders say it is safe, and have your system checked before you use it again.