What Are the Signs of a Carbon Monoxide Gas Leak?

Carbon monoxide (CO) is called the “silent killer” for a reason. It’s invisible, odorless and tough to recognize without the right tools. If it accumulates in your home, it can quickly become a danger for you and your family. So, how do you protect yourself against something you can’t really notice naturally?

The key is to use carbon monoxide detectors. These alarms are the initial line of defense, notifying you of the presence of CO gas before the situation reaches dangerous levels. But aside from a detector going off, how can you know if there’s a carbon monoxide leak in your home? Below are 10 warning signs to be aware of.

1. Condensation on Windows Closest to Appliances

If you spot lots of condensation on your windows, especially near a fuel-burning appliance like a gas fireplace, this could indicate that something isn’t venting correctly. While condensation by itself may not mean CO, this still warrants investigation.

2. Discoloration or Soot-Like Stains

Fuel-powered appliances should have clear exhaust. If you see brownish-yellow or soot-like stains around a heating system, fireplace or boiler, it could mean something’s wrong with the combustion process. This can signal a carbon monoxide leak.

3. Exhaust Fumes Are Inside

If you start to smell exhaust fumes indoors, you are in danger of carbon monoxide symptoms. Fuel-burning appliances like cars, charcoal grills and generators should exclusively be used outdoors to prevent an accumulation of exhaust fumes indoors.

4. Soot in or Around a Natural Gas-Burning Fireplace

Your chimney should channel smoke and other gases up through and out the chimney. Finding soot inside or around the fireplace is a red flag, especially if there’s more than usual. A clogged chimney could be the reason carbon monoxide is leaking back indoors.

5. Weaker or No Draft in the Chimney

Speaking of chimneys, a properly working one should have the solid updrafts to fully pull out smoke and other fumes. If you notice weak airflow or even no draft at all, your chimney could be blocked, pushing carbon monoxide right back indoors.

6. Discolored or Flickering Flames

Most gas-burning appliances should produce a steady blue flame. When the flame is weak and yellow (and it’s not a decorative gas fireplace), it means the gas is burning inefficiently and may be emitting carbon monoxide.

7. Solid Fuel Fires Aren’t Burning as Fast

In situations where your wood or coal stove starts struggling to burn all the way through or has trouble staying lit, it could have a ventilation issue, raising the risk of CO buildup.

Symptoms of CO Poisoning

If you miss the other signs of a carbon monoxide leak in time, the next clue could come from your health. Symptoms of CO poisoning include:

Flu-like symptoms
Headaches
Dizziness
Nausea or vomiting
Shortness of breath
Confusion
And fatigue

If you or anyone in your family suddenly feels sick, especially together with any of the warning signs listed above, leave the house right away for fresh air before you dial 911.

Prevent CO Poisoning and Gas Leaks with These Safety Tips

Prevention is always better than a cure, especially in the case of CO gas exposure. To start, check that there are carbon monoxide detectors in all the right places. Building codes require them in hallways near all bedrooms, on each level of the house and in rooms with gas-powered equipment. For extra safety, it’s smart to set up interconnected detectors so that if one goes off, all of them will raise the alarm. Check your alarms monthly and swap them out when necessary, usually every five to seven years.

In addition to using carbon monoxide detectors, follow these safety tips: