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, but it can lead to unconsciousness, brain damage or death. Because of this, more than 400 people die of accidental carbon monoxide exposure each year, a larger fatality rate versus any other kind of poisoning.

As the weather cools off, you seal your home for the winter and count on heating appliances to remain warm. This is where the risk of carbon monoxide poisoning is highest. The good news is you can defend your family from a gas leak in several ways. One of the most effective methods is to install CO detectors around your home. Try this guide to better understand where carbon monoxide is produced 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 can appear whenever a fuel source is ignited, like natural gas, propane, oil, charcoal, gasoline, woo, and more. Frequent causes of carbon monoxide in a house consist of:

  • Overloaded clothes dryer vent
  • Malfunctioning water heater
  • Furnace or boiler with a cracked heat exchanger
  • Closed fireplace flue during an active fire
  • Improperly vented gas or wood stove
  • Vehicle running 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 start an alarm when they sense a certain concentration of smoke caused by a fire. Having functional smoke detectors decreases the risk of dying in a house fire by around 55 percent.

Smoke detectors come in two basic types—ionization detectors and photoelectric detectors. Ionization detection functions well with quick-moving fires that emit large flames, while photoelectric detection is more applicable for smoldering, smoky fires. The newest smoke detectors come with both forms of alarms in one unit to increase the chance of sensing a fire, regardless of how it burns.

Clearly, smoke detectors and CO alarms are similarly essential home safety devices. If you inspect the ceiling and see an alarm of some kind, you may not recognize whether it’s a smoke detector or a carbon monoxide alarm. The visual difference depends on the brand and model you have. Here are several factors to keep in mind:

  • Most devices are properly labeled. If not, look for a brand and model number on the back of the detector and look it up online. You can also find a manufacture date. If the device is older than 10 years, replace it at the earliest opportunity.
  • Plug-in devices that extract power from an outlet are almost always carbon monoxide sensors94. The device will be labeled as such.
  • Some alarms will be two-in-one, sensing both smoke and carbon monoxide with an indicator light for each. That being said, it can be difficult to tell with no label on the front, so reviewing the manufacturing details on the back is worthwhile.

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 the number of bedrooms. Use these guidelines to guarantee complete coverage:

  • Install carbon monoxide detectors near wherever people sleep: CO gas leaks are most likely at night when furnaces are running frequently to keep your home warm. Therefore, each bedroom 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 adequate.
  • Add detectors on every floor:
    Concentrated carbon monoxide buildup can become caught on a single floor of your home, so try to have at least one CO detector on every level.
  • Put in detectors within 10 feet of an attached garage door: A lot of people accidentally leave their cars running in the garage, leading to dangerous carbon monoxide buildup, even while the large garage door is wide open. A CO alarm immediately inside the door—and in the room above the garage—alerts you of heightened carbon monoxide levels inside your home.
  • Have detectors at the appropriate height: Carbon monoxide is a similar density as air, but it’s often carried along with the hot air released by combustion appliances. Having detectors close to the ceiling is best to catch this rising air. Models that come with digital readouts are best located at eye level to make them easier to read.
  • Install detectors at least 15 feet from combustion appliances: A few fuel-burning machines give off a small, harmless amount of carbon monoxide at startup. This dissipates quickly, but if a CO detector is installed right next to it, it may give off false alarms.
  • Install detectors away from extreme heat and humidity: Carbon monoxide detectors have certain tolerances for heat and humidity. To reduce false alarms, try not to install 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 will sometimes encourage testing once a month and resetting to ensure proper functionality. Also, change out 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 completely after 10 years or as outlined by the manufacturer’s recommendations.

How to test your carbon monoxide alarm

It only takes a minute to test your CO alarm. Read the instruction manual for directions unique to your unit, knowing that testing uses this general process:

  • Press and hold the Test button. It may need 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 continues beeping when you let go of the button, press and hold it again for five seconds to stop it.

Change the batteries if the unit won't work as expected during the test. If replacement batteries don’t change anything, 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 a test or after replacing the batteries. Some models automatically reset themselves in under 10 minutes of these events, while others need a manual reset. The instruction manual will note which function you should use.

Carry out 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 notice 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 support from the manufacturer, or get rid of the faulty detector.

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

Listen to these steps to protect your home and family:

  • Do not dismiss the alarm. You won't always be able to detect unsafe levels of carbon monoxide until it’s too late, so anticipate the alarm is operating properly when it is triggered.
  • Evacuate all people and pets immediately. If you can, open windows and doors on your way out to try and thin out the concentration of CO gas.
  • Call 911 or your local fire department and report that the carbon monoxide alarm has gone off.
  • It's wrong to think 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 source might still be producing carbon monoxide.
  • When emergency responders come, they will enter your home, evaluate 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 will sometimes need to arrange repair services to keep the problem from returning.

Get Support from McKinley Heating Service Experts

With the appropriate precautions, there’s no need to be afraid of carbon monoxide poisoning in your home. Along with installing CO alarms, it’s worthwhile to maintain your fuel-burning appliances, especially as winter arrives.

The team at McKinley Heating Service Experts is happy to inspect, clean, diagnose and repair issues with furnaces, boilers, water heaters and other combustion appliances. We recognize which signs could mean a potential carbon monoxide leak— like excessive 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 McKinley Heating Service Experts for more information.

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