Carbon Monoxide Detectors: Ultimate Guide

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

When the weather cools down, you close up your home for the winter and rely on heating appliances to keep warm. This is when the threat of carbon monoxide exposure is highest. The good news is you can defend your family from a gas leak in a variety of ways. One of the most successful methods is to install CO detectors around your home. Use this guide to better understand where carbon monoxide can appear from and how to make the most of your CO detectors.

What produces carbon monoxide in a house?

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

  • Blocked up clothes dryer vent
  • Faulty water heater
  • Furnace or boiler with a cracked heat exchanger
  • Closed fireplace flue while a fire is lit
  • Poorly vented gas or wood stove
  • Vehicle running in the garage
  • Portable generator, grill, power tool or lawn equipment operating in the garage

Do smoke detectors sense carbon monoxide?

No, smoke detectors do not detect carbon monoxide. Alternatively, they begin an alarm when they sense a certain amount of smoke caused by a fire. Possessing reliable smoke detectors lowers the risk of dying in a house fire by around 55 percent.

Smoke detectors come in two main modes—ionization detectors and photoelectric detectors. Ionization detection is ideal with quick-moving fires that emit large flames, while photoelectric models are more effective with smoldering, smoky fires. A few smoke detectors come with both types of alarms in one unit to increase the chance of responding to a fire, no matter how it burns.

Unmistakably, smoke detectors and CO alarms are both essential home safety devices. If you check the ceiling and find an alarm of some kind, you may not realize whether it’s a smoke detector or a carbon monoxide alarm. The visual discrepancy is based on the brand and model you prefer. Here are a few factors to consider:

  • Quality devices are visibly labeled. If not, try to find a brand and model number on the back of the detector and locate it online. You will also find a manufacture date. If the device is more than 10 years old, replace it right away.
  • Plug-in devices that extract power through an outlet are typically carbon monoxide alarms]]94. The device {should be labeled as such.
  • Some alarms will be two-in-one, detecting both smoke and carbon monoxide with a different indicator light for each. That being said, it can be difficult to tell without a 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 require is dependent on your home’s size, how many floors it has and the number of bedrooms. Consider these guidelines to ensure complete coverage:

  • Place carbon monoxide detectors around wherever people sleep: CO gas exposure is most prevalent at night when furnaces must run frequently to keep your home heated. As a result, each bedroom should have a carbon monoxide alarm installed about 15 feet of the door. If two bedroom doors are less than 30 feet apart, just one detector is sufficient.
  • Put in detectors on every floor: Dangerous carbon monoxide gas can become caught on a single floor of your home, so make sure you have at least one CO detector on every level.
  • Put in detectors within 10 feet of the internal garage door: A lot of people accidentally leave their cars idling in the garage, resulting in dangerous carbon monoxide gas, even if the large garage door is completely open. A CO detector right inside the door—and in the room up above the garage—alerts you of increased carbon monoxide levels entering your home.
  • Have detectors at the appropriate height: Carbon monoxide weighs about the same as air, but it’s commonly carried upward in the hot air created by combustion appliances. Putting in detectors near the ceiling is best to catch this rising air. Models that include digital readouts are best located at eye level to make them easier to read.
  • Add detectors about 15 feet from combustion appliances: Some fuel-burning machines give off a tiny, non-toxic amount of carbon monoxide when they start. This disperses quickly, but if a CO detector is positioned too close, it may give off false alarms.
  • Put in detectors away from excess heat and humidity: Carbon monoxide detectors have specified tolerances for heat and humidity. To minimize false alarms, try not to install them in bathrooms, in harsh sunlight, around air vents, or close to heat-generating appliances.

How do I test/troubleshoot a carbon monoxide detector?

Depending on the model, the manufacturer will sometimes recommend monthly tests and resetting to ensure proper functionality. Also, replace the batteries in battery-powered units twice a year. For hardwired units, replace the backup battery annually or when the alarm starts chirping, whichever starts first. Then, replace the CO detector entirely after 10 years or in line with the manufacturer’s guidelines.

How to test your carbon monoxide alarm

It only takes a minute to test your CO detector. Read the instruction manual for directions individual to your unit, knowing that testing follows 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 functioning correctly.
  • Let go of the Test button and wait for two fast 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.

Replace the batteries if the unit fails to perform as expected for the test. If replacement batteries don’t change anything, replace the detector immediately.

How to reset your carbon monoxide alarm

You only have to reset your unit once the alarm goes off, after a test or after swapping the batteries. Certain models automatically reset themselves within 10 minutes of these events, while other alarms require a manual reset. The instruction manual can note which function you should use.

Use 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, 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 replace the detector.

What should I do if a carbon monoxide alarm starts?

Listen to these steps to safeguard your home and family:

  • Do not ignore the alarm. You won’t always be able to notice dangerous levels of carbon monoxide until it’s too late, so expect the alarm is functioning properly when it starts.
  • Evacuate all people and pets immediately. If you’re able to, 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 explain that the carbon monoxide alarm has triggered.
  • Do not assume it’s safe to reenter your home when the alarm stops running. Opening windows and doors may help air it out, but the source may still be creating carbon monoxide.
  • When emergency responders arrive, they will enter your home, evaluate carbon monoxide levels, look for 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 arrange repair services to prevent the problem from recurring.

Seek Support from Stevenson Service Experts

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

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

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

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