What Are the Red Flags of a Carbon Monoxide Leak?

Carbon monoxide (CO) is called the “silent killer” for a reason. It’s invisible, scentless and difficult to notice without proper 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 guard against something you can’t see, smell or taste?

The key is to use carbon monoxide detectors. These safety devices are the initial line of defense, warning you about the presence of CO gas before the situation gets dangerous. But besides a detector going off, how can you tell if there’s a carbon monoxide leak in your home? Below are 10 signs to watch out for.

1. Condensation on Windows Closest to Appliances

If you notice lots of condensation on your windows, namely near a fuel-burning appliance like a gas fireplace, this could mean that something isn’t venting correctly. While condensation alone isn’t always CO-related, this clue warrants investigation.

2. Yellow or Brown Stains

Combustion-based appliances should have unobstructed ventilation. If you see brownish-yellow or dark stains around a furnace, fireplace or water heater, combustion isn’t happening as it should. This can be a sign of a carbon monoxide risk.

3. Exhaust Fumes Indoors

If you can smell or see exhaust fumes indoors, you are in danger of carbon monoxide exposure. Devices that burn fuel like cars, charcoal grills and generators should always be used safely outside the home to avoid the buildup of exhaust fumes indoors.

4. Soot in or Around Your Fireplace

Your fireplace vent should remove smoke and other gases up through and out the chimney. Seeing soot buildup around your fireplace is a red flag, especially if there’s an unusual amount. A clogged chimney could be why carbon monoxide is coming back into your home.

5. Weak or No Draft in the Chimney

On the topic of chimneys, a properly working one should have the strong airflow to fully remove smoke and other fumes. If you find reduced ventilation or even no draft at all, the chimney might be blocked, sending carbon monoxide backward.

6. Yellow or Inconsistent Flames

All appliances that use gas should have a steady blue flame. Whenever the flame is weaker and yellow (and it isn’t a decorative gas fireplace), it can mean the gas is burning inefficiently and could be producing carbon monoxide.

7. Solid Fuel Fires Burning Slowly

In situations where your wood-burning stove starts burning slower than usual or has trouble even staying on, it could have a venting problem, increasing the risk of CO buildup.

Signs You May Have CO Poisoning

If you miss the first red flags of a carbon monoxide leak in time, the next warning might come from your health and well-being. Symptoms of CO poisoning can be:

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 alongside any of the above signs, leave the house right away for fresh air before you dial 911.

Prevent CO Poisoning and Gas Leaks with These Safety Tips

It’s always better to prevent issues than respond to them, especially regarding carbon monoxide. To start, check that there are carbon monoxide detectors in all the right places. Building codes mandate them in hallways near all bedrooms, on each level of your home and in rooms with gas-powered equipment. For an additional safety measure, it’s best to install interconnected detectors so that whenever one detects carbon monoxide, all of them will alarm you as well. Perform monthly testing and replace them as needed, approximately every five to seven years.

Along with installing and maintaining carbon monoxide detectors, keep these safety precautions in mind: