Carbon Monoxide Detectors: Ultimate Guide

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

While the weather gets colder, you close up your home for the winter and rely on heating appliances to remain warm. This is where the danger of carbon monoxide exposure is highest. Fortunately you can protect your family from a gas leak in several ways. One of the most effective methods is to put in CO detectors throughout your home. Check out this guide to better understand where carbon monoxide comes from and how to make the most 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 produced anytime a fuel source is burned, such as 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 broken heat exchanger
  • Closed fireplace flue with a lit fire
  • Improperly 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 begin an alarm when they detect a certain amount of smoke generated by a fire. Installing functional smoke detectors reduces the risk of dying in a house fire by about 55 percent.

Smoke detectors are available in two basic types—ionization detectors and photoelectric detectors. Ionization detection works best with fast-moving fires that emit large flames, while photoelectric detection is more effective with smoldering, smoky fires. A few smoke detectors incorporate both kinds of alarms in a single unit to maximize the chance of responding to a fire, regardless of how it burns.

Clearly, smoke detectors and CO alarms are similarly beneficial home safety devices. If you look up at the ceiling and see an alarm of some kind, you may not realize whether it’s a smoke detector or a carbon monoxide alarm. The visual difference is determined by the brand and model you want. Here are several factors to consider:

  • Quality devices are clearly labeled. If not, look for a brand and model number on the back of the detector and look it up online. You will also find a manufacture date. If the device is older than 10 years, replace it as soon as possible.
  • Plug-in devices that extract power from an outlet are typically carbon monoxide alarms94. The device should be labeled saying as much.
  • Some alarms will be two-in-one, offering protection against both smoke and carbon monoxide with a separate indicator light for each. Still, it can be hard to tell with no label on the front, so checking the manufacturing details on the back is smart.

How many carbon monoxide detectors will I want in my home?

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

  • Add carbon monoxide detectors around bedrooms: CO gas leaks are most prevalent at night when furnaces have to run constantly to keep your home warm. Therefore, all bedrooms should have a carbon monoxide sensor installed around 15 feet of the door. If a couple of bedroom doors are less than 30 feet apart, a single alarm is adequate.
  • Put in detectors on each 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 every level.
  • Install detectors within 10 feet of the internal garage door: Many people end up leaving their cars running in the garage, producing dangerous carbon monoxide gas, even when the large garage door is wide open. A CO sensor immediately inside the door—and in the room up above the garage—alerts you of heightened carbon monoxide levels inside your home.
  • Install detectors at the correct height: Carbon monoxide features a weight similar to air, but it’s commonly carried upward in the hot air released by combustion appliances. Installing detectors up against the ceiling is best to catch this rising air. Models 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 produce a small, harmless amount of carbon monoxide at startup. This dissipates quickly, but in situations where a CO detector is positioned too close, it may trigger false alarms.
  • Have detectors away from high heat and humidity: Carbon monoxide detectors have certain tolerances for heat and humidity. To reduce false alarms, avoid installing them in bathrooms, in strong sunlight, next to air vents, or close to heat-generating appliances.

How do I test/troubleshoot a carbon monoxide sensor?

Depending on the design, the manufacturer will sometimes suggest testing once a month and resetting to sustain proper functionality. Also, change out the batteries in battery-powered units every six months. For hardwired units, replace the backup battery annually or when the alarm starts chirping, whichever starts first. Then, replace the CO detector outright after 10 years or in line with the manufacturer’s recommendations.

How to test your carbon monoxide alarm

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

  • Press and hold the Test button. It might take 5 to 20 seconds for the alarm to begin.
  • Loud beeping signifies the detector is working correctly.
  • Let go of the Test button and wait for two short beeps, a flash or both. If the device continues beeping when you let go of the button, press and hold it again for five seconds to stop it.

Replace the batteries if the unit won't work as expected after the test. If replacement batteries don’t change anything, replace the detector entirely.

How to reset your carbon monoxide alarm

You only need to reset your unit after the alarm goes off, after testing the device or after swapping the batteries. Certain models automatically reset themselves within 10 minutes of these events, while other alarms need a manual reset. The instruction manual can 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 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 help from the manufacturer, or replace the detector.

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

Listen to these steps to protect your home and family:

  • Do not dismiss the alarm. You may not be able to notice hazardous levels of carbon monoxide until it’s too late, so assume the alarm is functioning properly when it goes off.
  • Evacuate all people and pets immediately. If you're able to, open windows and doors on your way out to attempt to dilute the concentration of CO gas.
  • Call 911 or a local fire department and explain that the carbon monoxide alarm has gone off.
  • Do not assume it’s safe to reenter your home when the alarm stops running. Opening windows and doors might help air it out, but the root cause might still be generating carbon monoxide.
  • When emergency responders arrive, they will enter your home, measure carbon monoxide levels, try to find the source of the CO leak and establish if it’s safe to go back inside. Depending on the cause, you may need to arrange repair services to keep the problem from reappearing.

Seek Support from Service Experts Heating & Air Conditioning

With the appropriate precautions, there’s no need to be afraid of carbon monoxide inhalation 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 Service Experts Heating & Air Conditioning is happy to inspect, clean, diagnose and repair malfunctions with furnaces, boilers, water heaters and other combustion appliances. We recognize which signs could mean a potential carbon monoxide leak— including increased 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 Service Experts Heating & Air Conditioning for more information.