Carbon Monoxide Detectors: Ultimate Guide

Carbon monoxide (CO) is one of the most hazardous gases found in the home. Dubbed the “silent killer,” CO gas is colorless, odorless, tasteless and non-irritating, yet it can cause unconsciousness, brain damage or death. Because of this, more than 400 people die of accidental carbon monoxide exposure each year, a larger fatality rate than any other type of poisoning. 

As the weather cools off, you close up your home for the winter and rely on heating appliances to remain warm. This is when the risk of carbon monoxide inhalation is highest. The good news is you can protect your family from carbon monoxide in a variety of ways. One of the most effective methods is to install CO detectors around your home. Use this guide to help you understand where carbon monoxide comes from and how to make the most of your CO alarms. 

What causes carbon monoxide in a house? 

Carbon monoxide is a byproduct of incomplete combustion. As a result, this gas can appear anytime a fuel source is ignited, such as natural gas, propane, oil, charcoal, gasoline, woo, and more. Common causes of carbon monoxide in a house include: 

• Clogged clothes dryer vent 

• Malfunctioning water heater 
• Furnace or boiler with a cracked heat exchanger
• Closed fireplace flue while a fire is lit 
• Improperly vented gas or wood stove 
• Vehicle idling in the garage 

• Portable generator, grill, power tool or lawn equipment being used in the garage 

Do smoke detectors detect carbon monoxide? 

No, smoke detectors do not detect carbon monoxide. Instead, they sound an alarm when they sense a certain concentration of smoke caused by a fire. Having reliable smoke detectors reduces the risk of dying in a house fire by nearly 55 percent. 

Smoke detectors come in two basic forms—ionization detectors and photoelectric detectors. Ionization detection works best with fast-moving fires that generate large flames, while photoelectric detectors are more effective with smoldering, smoky fires. Some newer smoke detectors come with both types of alarms in a single unit to increase the chance of sensing a fire, no matter how it burns. 

Clearly, smoke detectors and CO alarms are similarly important home safety devices. If you check the ceiling and find an alarm of some kind, you may not know whether it’s a smoke detector or a carbon monoxide alarm. The visual contrast depends on the brand and model you want. Here are some factors to keep in mind: 

• Quality devices are clearly labeled. If not, check for a brand and model number on the back of the detector and locate it online. You should also find a manufacture date. If the device is more than 10 years old, replace it as soon as possible. 
• Plug-in devices that draw power from an outlet are almost always carbon monoxide sensors be labeled as such. 
• Some alarms will be two-in-one, detecting both smoke and carbon monoxide with a different indicator light for each. Still, it can be hard to tell without a label on the front, so checking the manufacturing details on the back is smart. 

How many carbon monoxide detectors should I install in my home? 

The number of CO alarms you require is determined by your home’s size, number of floors and bedroom arrangement. Follow these guidelines to ensure thorough coverage: 

• Install carbon monoxide detectors near sleeping areas: CO gas poisoning is most common at night when furnaces have to run frequently to keep your home warm. Therefore, all bedrooms should have a carbon monoxide detector installed within 15 feet of the door. If multiple bedroom doors are less than 30 feet apart, one detector is sufficient. 
• Install detectors on every floor: 
  Dangerous carbon monoxide buildup can become trapped on a single floor of your home, so do your best to have at least one CO detector on every level. 
• Install detectors within 10 feet of the internal garage door: Many people unsafely leave their cars idling in the garage, resulting in dangerous carbon monoxide buildup, even when the large garage door is wide open. A CO detector immediately inside the door—and in the room above the garage—alerts you of elevated carbon monoxide levels entering your home. 
• Install detectors at the proper height: Carbon monoxide weighs about the same as air, but it’s often carried upward in the hot air created by combustion appliances. Installing detectors near the ceiling is best to catch this rising air. Models with digital readouts are best installed at eye level to make sure they’re easy to read. 
• Install detectors about 15 feet from combustion appliances: Some fuel-burning machines give off a tiny, harmless amount of carbon monoxide when they start. This dissipates quickly, but when a CO detector is positioned too close, it could give off false alarms. 

• Install detectors away from high heat and humidity: Carbon monoxide detectors have specific tolerances for heat and humidity. To reduce false alarms, avoid installing them in bathrooms, in direct sunlight, around air vents, or close to heat-generating appliances. 

How do I test/troubleshoot a carbon monoxide alarm? 

Depending on the model, the manufacturer may encourage monthly testing and resetting to ensure proper functionality. Also, replace the batteries in battery-powered units every six months. For hardwired units, replace the backup battery annually or when the alarm starts chirping, whichever comes first. Then, replace the CO detector entirely every 10 years or according to the manufacturer’s guidelines. 

How to test your carbon monoxide alarm 

It only takes a minute to test your CO detector. Review the instruction manual for directions individual to your unit, knowing that testing follows this general procedure: 

• Press and hold the Test button. It might take 5 to 20 seconds for the alarm to start. 
• Loud beeping means the detector is operating correctly. 
• Release the Test button and wait for two quick beeps, a flash or both. If the device continues beeping when you release the button, press and hold it again for five seconds to silence it. 

Swap out the batteries if the unit fails to perform 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 only have to reset your unit when the alarm goes off, after testing the device or after replacing the batteries. Some models automatically reset themselves within 10 minutes of these events, while others require a manual reset. The instruction manual will note which function applies. 

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 see a flash, attempt the reset again or replace the batteries. If it’s still not working, troubleshoot your carbon monoxide alarm with help from the manufacturer, or replace the detector. 

What do I do if a carbon monoxide alarm is triggered? 

Use these steps to protect your home and family: 

• Do not ignore the alarm. You may not be able to detect unsafe levels of carbon monoxide until it’s too late, so assume the alarm is operating correctly when it is triggered. 
• Evacuate all people and pets as quickly as possible. If you can, open windows and doors on your way out to try and dilute the concentration of CO gas. 
• Call 911 or your local fire department and report that the carbon monoxide alarm has gone off. 

• Do not assume it’s safe to reenter your home when the alarm stops beeping. Opening windows and doors may help air it out, but the source could still be producing carbon monoxide. 
• When emergency responders come, they will enter your home, measure carbon monoxide levels, check for the source of the CO leak and figure out if it’s safe to go back inside. Depending on the cause, you may need to schedule repair services to prevent the problem from recurring. 

Seek Support from Air Engineers Service Experts 

With the right precautions, there’s no need to fear carbon monoxide exposure in your home. In addition to installing CO alarms, it’s crucial to maintain your fuel-burning appliances, especially as winter gets underway. 

The team at Air Engineers Service Experts is qualified to inspect, clean, diagnose and repair problems with furnaces, boilers, water heaters and other combustion appliances. We know what signs could mean a possible carbon monoxide leak— including excessive soot, rusted flue pipes and a yellow, flickering burner flame—along with the necessary repairs to avoid them. 

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