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. Consequently, more than 400 people suffer fatal carbon monoxide influence each year, a steeper fatality rate than any other type of poisoning.

As the weather gets colder, you seal your home for the winter and trust in heating appliances to remain warm. These situations are when the risk of carbon monoxide inhalation is highest. Fortunately you can defend your family from a gas leak in several ways. One of the most successful methods is to add CO detectors throughout your home. Try this guide to help you understand where carbon monoxide can appear from and how to take full advantage of your CO detectors.

What causes carbon monoxide in a house?

Carbon monoxide is a byproduct of incomplete combustion. Because of this, this gas can appear anytime a fuel source burns, such as natural gas, propane, oil, charcoal, gasoline, woo, and more. Frequent causes of carbon monoxide in a house may be:

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

Do smoke detectors recognize carbon monoxide?

No, smoke detectors do not detect carbon monoxide. In fact, they start an alarm when they recognize a certain level of smoke caused by a fire. Installing functional smoke detectors lowers the risk of dying in a house fire by about 55 percent.

Smoke detectors are available in two basic forms—ionization detectors and photoelectric detectors. Ionization detection works best with fast-growing fires that produce large flames, while photoelectric detectors are more applicable for smoldering, smoky fires. Some newer smoke detectors incorporate both kinds of alarms in one unit to boost the chance of recognizing a fire, no matter how it burns.

Obviously, smoke detectors and CO alarms are equally beneficial home safety devices. If you inspect 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 difference depends on the brand and model you have. Here are a few factors to keep in mind:

  • Quality devices are properly labeled. If not, check 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 as soon as possible.
  • Plug-in devices that draw power through an outlet are generally carbon monoxide alarms]]94. The device {should be labeled saying as much.
  • Some alarms are really two-in-one, sensing both smoke and carbon monoxide with a separate indicator light for each. Still, it can be tough to tell without a label on the front, so double 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 need is dependent on your home’s size, number of floors and the number of bedrooms. Use these guidelines to ensure thorough coverage:

  • Install carbon monoxide detectors around wherever people sleep: CO gas leaks are most prevalent at night when furnaces have to run constantly to keep your home comfortable. For that reason, all bedrooms should have a carbon monoxide detector installed around 15 feet of the door. If a couple of bedroom doors are less than 30 feet apart, just one detector is sufficient.
  • Put in detectors on each floor: Dense carbon monoxide gas can become caught on a single floor of your home, so make sure you have at least one CO detector on all floors.
  • Install detectors within 10 feet of the internal garage door: A surprising number of people end up leaving their cars on in the garage, leading to dangerous carbon monoxide buildup, even if the large garage door is fully open. A CO detector just inside the door—and in the room up above the garage—alerts you of heightened carbon monoxide levels entering your home.
  • Install detectors at the proper height: Carbon monoxide weighs about the same as air, but it’s commonly carried upward in the hot air released by combustion appliances. Having detectors close to the ceiling is ideal to catch this rising air. Models with digital readouts are best placed at eye level to keep them easy to read.
  • Add detectors around 15 feet from combustion appliances: Some fuel-burning machines emit a small, non-toxic amount of carbon monoxide as they first start running. This dissipates quickly, but in situations where a CO detector is positioned too close, it could trigger false alarms.
  • Have detectors away from high heat and humidity: Carbon monoxide detectors have specified tolerances for heat and humidity. To minimize 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 sensor?

Depending on the specific unit, the manufacturer will sometimes recommend monthly testing and resetting to ensure proper functionality. Also, replace the batteries in battery-powered units after 6 months. For hardwired units, replace the backup battery annually or when the alarm starts chirping, whichever happens first. Then, replace the CO detector completely every 10 years or as outlined by the manufacturer’s guidelines.

How to test your carbon monoxide alarm

You only need a minute to test your CO detector. Read the instruction manual for directions individual to your unit, with the knowledge that testing uses this general procedure:

  • Press and hold the Test button. It will sometimes need 5 to 20 seconds for the alarm to begin.
  • Loud beeping indicates the detector is functioning correctly.
  • Let go of 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.

Change the batteries if the unit isn’t performing as expected after the test. If replacement batteries don’t help, replace the detector entirely.

How to reset your carbon monoxide alarm

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

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 notice a beep or see a flash, attempt the reset again or replace the batteries. If that doesn’t help either, troubleshoot your carbon monoxide alarm with help from the manufacturer, or get rid of the faulty detector.

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

Listen to these steps to protect your home and family:

  • Do not disregard the alarm. You won’t always be able to identify dangerous levels of carbon monoxide until it’s too late, so assume the alarm is functioning correctly when it goes off.
  • Evacuate all people and pets as quickly as possible. If possible, open windows and doors on your way out to help dilute the concentration of CO gas.
  • Call 911 or a local fire department and inform them that the carbon monoxide alarm has started.
  • Don’t assume it’s safe to reenter your home when the alarm is no longer beeping. Opening windows and doors can help air it out, but the root cause could still be creating carbon monoxide.
  • When emergency responders come, they will search your home, evaluate carbon monoxide levels, check for the source of the CO leak and figure out if it’s safe to come back inside. Depending on the cause, you may need to schedule repair services to stop the problem from returning.

Find Support from Service Experts Heating, Air Conditioning & Plumbing

With the right precautions, there’s no need to worry about carbon monoxide poisoning in your home. Besides installing CO alarms, it’s worthwhile to maintain your fuel-burning appliances, namely as winter gets underway.

The team at Service Experts Heating, Air Conditioning & Plumbing is happy to inspect, clean, diagnose and repair problems with furnaces, boilers, water heaters and other combustion appliances. We understand what signs indicate a likely 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 Service Experts Heating, Air Conditioning & Plumbing for more information.

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