Carbon Monoxide Detectors: Ultimate Guide

Carbon monoxide (CO) is a potentially hazardous gas found in the home. Known as the “silent killer,” CO gas is colorless, odorless, tasteless and non-irritating, yet it can lead to unconsciousness, brain damage or death. As a result, more than 400 people die of accidental carbon monoxide influence each year, a steeper fatality rate than any other kind of poisoning. 

While the weather cools down, you seal your home for the winter and trust in heating appliances to keep warm. This is where the danger of carbon monoxide poisoning is highest. Thankfully you can safeguard your family from a gas leak in a variety of ways. One of the most successful methods is to add CO detectors throughout your home. Check out this guide to better understand where carbon monoxide comes from and how to take full advantage of your CO alarms. 

What generates carbon monoxide in a house? 

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

  • Overloaded clothes dryer vent 
  • Malfunctioning water heater 
  • Furnace or boiler with a damaged heat exchanger
  • Closed fireplace flue during an active fire 
  • Poorly vented gas or wood stove 
  • Vehicle sitting in the garage 
  • Portable generator, grill, power tool or lawn equipment being used in the garage 

Do smoke detectors recognize carbon monoxide? 

No, smoke detectors do not detect carbon monoxide. Alternatively, they start an alarm when they sense a certain level of smoke generated by a fire. Having reliable smoke detectors reduces the risk of dying in a house fire by around 55 percent

Smoke detectors come in two main types—ionization detectors and photoelectric detectors. Ionization detection is ideal with quick-moving fires that emit large flames, while photoelectric detectors are more applicable for smoldering, smoky fires. Some newer smoke detectors include both forms of alarms in one unit to increase the chance of sensing a fire, despite how it burns. 

Obviously, smoke detectors and CO alarms are both beneficial home safety devices. If you look up at the ceiling and find an alarm of some kind, you might not recognize whether it’s a smoke detector or a carbon monoxide alarm. The visual contrast depends on the brand and model you have. Here are a few factors to keep in mind: 

  • Some devices are clearly labeled. If not, look for a brand and model number on the back of the detector and find it online. You can also find a manufacture date. If the device is more than a decade old, replace it right away. 
  • Plug-in devices that extract power with an outlet are generally carbon monoxide will be labeled as such. 
  • Some alarms are really two-in-one, sensing both smoke and carbon monoxide with a different indicator light for each. Still, it can be hard to tell with no label on the front, so reviewing the manufacturing details on the back is worthwhile. 

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

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

  • Place carbon monoxide detectors nearby sleeping areas: CO gas leaks are most prevalent at night when furnaces must run constantly to keep your home comfortable. For that reason, every bedroom should have a carbon monoxide detector installed about 15 feet of the door. If multiple bedroom doors are less than 30 feet apart, a single alarm is sufficient. 
  • Add detectors on every floor: 
    Dangerous carbon monoxide gas can become trapped on a single floor of your home, so try to have at least one CO detector on each floor. 
  • Have detectors within 10 feet of an attached garage door: A lot of people accidentally leave their cars on in the garage, resulting in dangerous carbon monoxide buildup, even if the large garage door is wide open. A CO detector right inside the door—and in the room over the garage—alerts you of increased carbon monoxide levels entering your home. 
  • Have detectors at the proper height: Carbon monoxide is a similar density as air, but it’s often pushed up by the hot air produced by combustion appliances. Installing detectors close to the ceiling is ideal to catch this rising air. Models with digital readouts are best installed at eye level to make sure they’re easy to read. 
  • Put in detectors about 15 feet from combustion appliances: Certain fuel-burning machines produce a tiny, non-toxic amount of carbon monoxide at startup. This breaks up quickly, but when a CO detector is nearby, it might lead to false alarms. 
  • Install detectors away from extreme heat and humidity: Carbon monoxide detectors have specified tolerances for heat and humidity. To reduce false alarms, try not to install them in bathrooms, in strong sunlight, near air vents, or close to heat-generating appliances. 

How do I test/troubleshoot a carbon monoxide alarm? 

Depending on the specific unit, the manufacturer will sometimes encourage testing once a month and resetting to sustain proper functionality. Also, swap out the batteries in battery-powered units every six months. For hardwired units, replace the backup battery every year or when the alarm is chirping, whichever comes first. Then, replace the CO detector completely after 10 years or in line with the manufacturer’s recommendations. 

How to test your carbon monoxide alarm 

It only takes a minute to test your CO alarm. Check the instruction manual for directions unique to your unit, with the knowledge that testing practices this general routine: 

  • Press and hold the Test button. It may take 5 to 20 seconds for the alarm to go off. 
  • Loud beeping signifies the detector is working 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. 

Swap out the batteries if the unit won’t work as expected after the test. If replacement batteries don’t help, replace the detector immediately. 

How to reset your carbon monoxide alarm 

You’re only required to reset your unit after the alarm goes off, after testing the device or after swapping 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 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 listen for a beep, a flash or both. 

If you don’t notice 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 support from the manufacturer, or get rid of the faulty detector. 

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

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

  • Do not dismiss the alarm. You might not be able to detect unsafe levels of carbon monoxide until it’s too late, so anticipate the alarm is working correctly when it starts. 
  • Evacuate all people and pets as quickly as possible. If you can, open windows and doors on your way out to help dilute the concentration of CO gas. 
  • Call 911 or the local fire department and report that the carbon monoxide alarm has triggered. 
  • 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 may still be creating carbon monoxide. 
  • When emergency responders show up, they will go into your home, assess carbon monoxide levels, look for the source of the CO leak and establish if it’s safe to come back inside. Depending on the cause, you may need to request repair services to keep the problem from returning. 

Seek Support from Service Experts Heating, Air Conditioning & Plumbing 

With the proper precautions, there’s no need to worry about carbon monoxide exposure in your home. Along with installing CO alarms, it’s worthwhile to maintain your fuel-burning appliances, particularly as winter starts. 

The team at Service Experts Heating, Air Conditioning & Plumbing is ready to inspect, clean, diagnose and repair problems with furnaces, boilers, water heaters and other combustion appliances. We recognize which signs indicate a possible carbon monoxide leak— including increased 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 & Plumbing for more information. 

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