Carbon Monoxide Detectors: Ultimate Guide

Carbon monoxide (CO) is a common risk found in the home. Nicknamed the “silent killer,” CO gas is colorless, odorless, tasteless and non-irritating, however it can lead to unconsciousness, brain damage or death. As a result, more than 400 people suffer fatal carbon monoxide poisoning each year, a larger fatality rate versus other types of poisoning.

When the weather cools down, you seal your home for the winter and count on heating appliances to keep warm. This is when the threat of carbon monoxide inhalation is highest. The good news is you can defend your family from carbon monoxide in several ways. One of the most efficient methods is to add CO detectors around your home. Check out this guide to help you understand where carbon monoxide is produced and how to reap the benefits of your CO detectors.

What causes carbon monoxide in a house?

Carbon monoxide is a byproduct of incomplete combustion. As a result, this gas is generated when a fuel source burns, including natural gas, propane, oil, charcoal, gasoline, woo, and more. Common causes of carbon monoxide in a house consist of:

Clogged clothes dryer vent
Broken down water heater
Furnace or boiler with a cracked heat exchanger
Closed fireplace flue during an active fire
Poorly vented gas or wood stove
Vehicle idling in the garage
Portable generator, grill, power tool or lawn equipment running in the garage

Do smoke detectors recognize carbon monoxide?

No, smoke detectors do not detect carbon monoxide. In fact, they begin an alarm when they recognize a certain concentration of smoke generated by a fire. Installing dependable smoke detectors reduces the risk of dying in a house fire by nearly 55 percent.

Smoke detectors are offered in two main modes—ionization detectors and photoelectric detectors. Ionization detection functions well with quick-moving fires that produce large flames, while photoelectric detection is more applicable for smoldering, smoky fires. Some newer smoke detectors come with both kinds of alarms in a single unit to maximize the chance of recognizing a fire, no matter how it burns.

Unmistakably, smoke detectors and CO alarms are equally important home safety devices. If you check the ceiling and find an alarm of some kind, you won't always realize whether it’s a smoke detector or a carbon monoxide alarm. The visual contrast is based on the brand and model you have. Here are a few factors to remember:

Some devices are clearly labeled. If not, try to find a brand and model number on the back of the detector and locate it online. You can also find a manufacture date. If the device is older than 10 years, replace it as soon as possible.
Plug-in devices that use power with an outlet are almost always carbon monoxide sensors94. The device should be labeled so.
Some alarms will be two-in-one, sensing both smoke and carbon monoxide with a different indicator light for each. Still, it can be difficult to tell if there's no label on the front, so checking the manufacturing details on the back is smart.

How many carbon monoxide detectors do I need in my home?

The number of CO alarms you should have depends on your home’s size, the number of stories and bedroom arrangement. Follow these guidelines to ensure thorough coverage:

Install carbon monoxide detectors nearby bedrooms: CO gas exposure is most common at night when furnaces are running more often to keep your home comfortable. Therefore, every bedroom should have a carbon monoxide sensor installed within 15 feet of the door. If a couple of bedroom doors are less than 30 feet apart, just one detector is sufficient.
Install detectors on every floor:
Concentrated carbon monoxide buildup can become stuck on a single floor of your home, so do your best to have at least one CO detector on all floors.
Put in detectors within 10 feet of an attached garage door: A surprising number of people end up leaving their cars idling in the garage, producing dangerous carbon monoxide buildup, even when the large garage door is completely open. A CO alarm just inside the door—and in the room above the garage—alerts you of elevated carbon monoxide levels entering your home.
Put in detectors at the appropriate height: Carbon monoxide weighs about the same as air, but it’s commonly carried along with the hot air created by combustion appliances. Installing detectors near the ceiling is ideal to catch this rising air. Models that come with digital readouts are best placed at eye level to keep them easy to read.
Add detectors about 15 feet from combustion appliances: A few fuel-burning machines emit a tiny, non-toxic amount of carbon monoxide when they start. This dissipates quickly, but if a CO detector is installed right next to it, it might trigger false alarms.
Install detectors away from high heat and humidity: Carbon monoxide detectors have certain tolerances for heat and humidity. To reduce false alarms, don't install them in bathrooms, in harsh sunlight, around air vents, or close to heat-generating appliances.

How do I test/troubleshoot a carbon monoxide alarm?

Depending on the design, the manufacturer may recommend monthly tests and resetting to sustain proper functionality. Also, change out the batteries in battery-powered units after 6 months. For hardwired units, replace the backup battery once a year or when the alarm begins chirping, whichever comes first. Then, replace the CO detector entirely after 10 years or as outlined by the manufacturer’s recommendations.

How to test your carbon monoxide alarm

All it takes is a minute to test your CO alarm. Read the instruction manual for directions specific to your unit, understanding that testing uses this general process:

Press and hold the Test button. It will sometimes need 5 to 20 seconds for the alarm to go off.
Loud beeping signifies the detector is operating correctly.
Release the Test button and wait for two quick beeps, a flash or both. If the device keeps beeping when you let go of the button, press and hold it again for five seconds to silence it.

Change the batteries if the unit won't work as expected during the test. If replacement batteries don’t make a difference, replace the detector immediately.

How to reset your carbon monoxide alarm

You're only required to reset your unit when the alarm goes off, after running a test or after replacing the batteries. Some models automatically reset themselves in 10 minutes of these events, while other alarms need a manual reset. The instruction manual will note which function you should use.

Follow these steps to reset your CO detector manually:

Press and hold the Reset button for 5 to 10 seconds.
Release the button and wait for a beep, a flash or both.

If you don’t hear a beep or observe a flash, start the reset again or replace the batteries. If that doesn't help either, troubleshoot your carbon monoxide alarm with assistance from the manufacturer, or install a new detector.

What can I do if a carbon monoxide alarm goes off?

Use these steps to take care of your home and family:

Do not ignore the alarm. You may not be able to recognize dangerous levels of carbon monoxide until it’s too late, so assume the alarm is functioning correctly when it starts.
Evacuate all people and pets as quickly as possible. If you're able to, open windows and doors on your way out to attempt to weaken the concentration of CO gas.
Call 911 or your local fire department and report that the carbon monoxide alarm has started.
Don't assume it’s safe to reenter your home when the alarm is no longer beeping. Opening windows and doors might help air it out, but the root cause might still be generating carbon monoxide.
When emergency responders show up, they will search your home, measure carbon monoxide levels, try to find the source of the CO leak and figure out if it’s safe to go back inside. Depending on the cause, you might need to request repair services to keep the problem from reappearing.

Seek Support from Service Experts Heating & Air Conditioning

With the right precautions, there’s no need to worry about carbon monoxide inhalation in your home. Besides installing CO alarms, it’s crucial to maintain your fuel-burning appliances, especially as winter starts.

The team at Service Experts Heating & Air Conditioning is happy to inspect, clean, diagnose and repair malfunctions with furnaces, boilers, water heaters and other combustion appliances. We understand what signs suggest a potential carbon monoxide leak— such as excess soot, rusted flue pipes and a yellow, flickering burner flame—along with the necessary repairs to resolve them.

Do you still have questions or concerns about CO exposure? Is it time to schedule annual heating services? Contact Service Experts Heating & Air Conditioning for more information.