What Are the Signs of a Carbon Monoxide Leak?

Carbon monoxide (CO) is known as the “silent killer” for a reason. It’s colorless, scentless and tough to recognize without the right tools. If it builds up in your home, it can rapidly turn into a serious threat for you and your family. So, how do you stay safe against something you can’t really notice naturally?

The key is to use carbon monoxide detectors. These safety devices are your first line of defense, notifying you of the presence of CO gas before the situation becomes life-threatening. But aside from a detector going off, how can you recognize if there’s a carbon monoxide leak in your home? Here are 10 signs to watch out for.

1. Condensation on Windows Near Appliances

If you see heavy condensation on your windows, particularly near a combustion-based system like a gas fireplace, this could suggest that ventilation isn’t working properly. While condensation by itself may not mean CO, this still deserves a closer look.

2. Brown, Sooty Stains

Combustion-based appliances should have clean, clear exhaust. If you see brownish-yellow or sooty stains around a furnace, fireplace or water heater, it could mean something’s wrong with the combustion process. This can be a sign of a carbon monoxide leak.

3. Exhaust Fumes Indoors

If you can smell exhaust fumes indoors, you are in danger of carbon monoxide symptoms. Fuel-burning appliances like cars, charcoal grills and generators should only be used outdoors to reduce the risk of exhaust fumes indoors.

4. Soot in or Around the Fireplace

Your fireplace vent should remove smoke and other gases up and out the chimney. Finding soot inside or around the fireplace is a warning sign, especially if there’s excessive amounts. An obstructed flue in the chimney could be the reason carbon monoxide is leaking back into your home.

5. Weak or No Draft from Your Chimney

Staying on the topic of chimneys, a properly working one needs the solid updrafts to fully ventilate smoke and other fumes. If you find weak airflow or even no draft at all, the chimney could be clogged, sending carbon monoxide backward.

6. Discolored or Inconsistent Flames

Gas-powered appliances should have a steady blue flame. Whenever the flame is weaker and yellow (and you don’t have a decorative gas fireplace), it can mean the gas has combustion issues and might be releasing carbon monoxide.

7. Solid Fuel Fires Aren’t Burning as Fast

In situations where your wood-burning stove begins struggling to burn all the way through or has trouble maintaining a flame, it could be dealing with a ventilation issue, raising the risk of CO buildup.

Signs You May Have CO Poisoning

If you fail to notice the other signs of a carbon monoxide leak in time, the next clue might come from your health and well-being. 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 starts getting 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, ensure you’ve installed carbon monoxide detectors in all the right places. Building codes mandate them in hallways near all bedrooms, on each floor of the house and in rooms with fuel-burning appliances. For extra safety, it’s best to set up interconnected detectors so that whenever one goes off, all of them will sound. Perform monthly testing and replace them as needed, usually every five to seven years.

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