Carbon Monoxide Detectors: Ultimate Guide

Carbon monoxide (CO) is a common risk found in the home. Dubbed the “silent killer,” CO gas is colorless, odorless, tasteless and non-irritating, however it can result in unconsciousness, brain damage or death. Consequently, more than 400 people die of accidental carbon monoxide poisoning each year, a higher fatality rate than other types of poisoning.

While the weather cools down, you close up your home for the winter and rely on heating appliances to keep warm. These situations are when the risk of carbon monoxide poisoning is highest. The good news is you can defend your family from carbon monoxide in different ways. One of the most effective methods is to install CO detectors throughout your home. Check out this guide to better understand where carbon monoxide can appear from and how to reap the benefits of your CO sensors.

What causes carbon monoxide in a house?

Carbon monoxide is a byproduct whenever something combusts. As a result, this gas can appear when a fuel source burns, such as natural gas, propane, oil, charcoal, gasoline, woo, and more. Common causes of carbon monoxide in a house include:

  • Overloaded clothes dryer vent
  • Broken down water heater
  • Furnace or boiler with a damaged 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 being used in the garage

Do smoke detectors recognize carbon monoxide?

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

Smoke detectors are offered in two basic modes—ionization detectors and photoelectric detectors. Ionization detection is ideal with fast-growing fires that emit large flames, while photoelectric detectors are more applicable for smoldering, smoky fires. The newest smoke detectors incorporate both kinds of alarms in one unit to boost the chance of recognizing a fire, no matter how it burns.

Unmistakably, smoke detectors and CO alarms are both beneficial home safety devices. If you inspect the ceiling and notice an alarm of some kind, you won’t always realize whether it’s a smoke detector or a carbon monoxide alarm. The visual difference is determined by the brand and model you prefer. Here are several factors to remember:

  • Quality devices are visibly labeled. If not, try to find 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 more than 10 years old, replace it at the earliest opportunity.
  • Plug-in devices that draw power from an outlet are almost always carbon monoxide will be labeled so.
  • Some alarms are really two-in-one, detecting both smoke and carbon monoxide with a separate indicator light for each. That being said, it can be difficult to tell if there’s no label on the front, so reviewing the manufacturing details on the back is your best bet.

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

The number of CO alarms you need depends on your home’s size, number of floors and the number of bedrooms. Consider these guidelines to ensure complete coverage:

  • Add carbon monoxide detectors nearby wherever people sleep: CO gas exposure is most prevalent at night when furnaces have to run constantly to keep your home comfortable. For that reason, every bedroom should have a carbon monoxide alarm installed within 15 feet of the door. If a couple of bedroom doors are less than 30 feet apart, one detector is enough.
  • Add detectors on every floor: Dense carbon monoxide gas can become stuck 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 an attached garage door: A lot of people unsafely leave their cars running in the garage, producing dangerous carbon monoxide buildup, even when the large garage door is fully open. A CO alarm immediately inside the door—and in the room above the garage—alerts you of increased carbon monoxide levels inside your home.
  • Install detectors at the appropriate height: Carbon monoxide weighs about the same as air, but it’s often carried along with the hot air created 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 make them easier to read.
  • Put in detectors at least 15 feet from combustion appliances: Certain fuel-burning machines give off a tiny, non-toxic amount of carbon monoxide as they first start running. This breaks up quickly, but if a CO detector is installed right next to it, it may lead to false alarms.
  • Put in 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 alarm?

Depending on the specific unit, the manufacturer may recommend testing once a month and resetting to maintain proper functionality. Also, replace the batteries in battery-powered units twice a year. For hardwired units, replace the backup battery once a year or when the alarm is chirping, whichever starts first. Then, replace the CO detector completely every 10 years or in line with the manufacturer’s instructions.

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, knowing 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 means 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.

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

How to reset your carbon monoxide alarm

You’re only required to reset your unit when the alarm goes off, after a test or after replacing the batteries. Some models automatically reset themselves in 10 minutes of these events, while other models need 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 hear a beep or see a flash, try the reset again or replace the batteries. If nothing happens, troubleshoot your carbon monoxide alarm with help from the manufacturer, or get rid of the faulty detector.

What should I do if a carbon monoxide alarm starts?

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

  • Do not ignore the alarm. You might not be able to recognize dangerous levels of carbon monoxide until it’s too late, so anticipate the alarm is functioning correctly when it goes off.
  • Evacuate all people and pets immediately. If possible, 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 inform them that the carbon monoxide alarm has gone off.
  • It’s wrong to think it’s safe to reenter your home when the alarm stops running. Opening windows and doors might help air it out, but the source may still be generating carbon monoxide.
  • When emergency responders show up, they will go into your home, evaluate carbon monoxide levels, try to find the source of the CO leak and establish if it’s safe to return. Depending on the cause, you will sometimes need to arrange repair services to keep the problem from returning.

Get Support from Service Experts Heating, Air Conditioning & Plumbing

With the proper precautions, there’s no need to be afraid of carbon monoxide inhalation in your home. Besides installing CO alarms, it’s worthwhile to maintain your fuel-burning appliances, namely as winter arrives.

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

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