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

As the weather gets colder, you insulate your home for the winter and count on heating appliances to stay warm. This is when the risk of carbon monoxide inhalation is highest. Fortunately you can safeguard your family from a gas leak in a variety of ways. One of the most effective methods is to put in CO detectors in your home. Try this guide to better understand where carbon monoxide comes from and how to make the most of your CO detectors.

What produces carbon monoxide in a house?

Carbon monoxide is a byproduct of something burned. As a result, this gas is produced whenever a fuel source is burned, like natural gas, propane, oil, charcoal, gasoline, woo, and more. Common causes of carbon monoxide in a house may be:

  • Clogged clothes dryer vent
  • Faulty water heater
  • Furnace or boiler with a damaged 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 operating in the garage

Do smoke detectors sense carbon monoxide?

No, smoke detectors do not detect carbon monoxide. Instead, they sound an alarm when they sense a certain concentration of smoke produced by a fire. Possessing functional smoke detectors lowers the risk of dying in a house fire by nearly 55 percent.

Smoke detectors are available in two basic types—ionization detectors and photoelectric detectors. Ionization detection works best with fast-moving fires that generate large flames, while photoelectric models are more effective with smoldering, smoky fires. The newest smoke detectors come with both kinds of alarms in one unit to increase the chance of sensing a fire, no matter how it burns.

Obviously, smoke detectors and CO alarms are equally important home safety devices. If you inspect the ceiling and find an alarm of some kind, you might not know whether it’s a smoke detector or a carbon monoxide alarm. The visual contrast is based on the brand and model you have. Here are several factors to keep in mind:

  • Most devices are visibly labeled. If not, try to find 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 older than 10 years, replace it as soon as possible.
  • Plug-in devices that extract power through an outlet are almost always carbon monoxide sensors be labeled as such.
  • Some alarms are really two-in-one, detecting both smoke and carbon monoxide with a different indicator light for each. Nevertheless, it can be tough 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 need is dependent on your home’s size, the number of stories and the number of bedrooms. Follow these guidelines to ensure total coverage:

  • Install carbon monoxide detectors near sleeping areas: CO gas leaks are most prevalent at night when furnaces have to run constantly to keep your home heated. As a result, all bedrooms should have a carbon monoxide sensor installed within 15 feet of the door. If a couple of bedroom doors are less than 30 feet apart, a single alarm is enough.
  • Install detectors on every floor: Dangerous carbon monoxide buildup can become stuck on a single floor of your home, so make sure you have at least one CO detector on every level.
  • Have detectors within 10 feet of an attached garage door: A surprising number of people accidentally leave their cars on in the garage, producing dangerous carbon monoxide buildup, even while the large garage door is completely open. A CO detector just inside the door—and in the room up above the garage—alerts you of heightened carbon monoxide levels inside your home.
  • Have detectors at the appropriate height: Carbon monoxide features a weight similar to air, but it’s often carried upward in the hot air produced by combustion appliances. Putting in detectors up against the ceiling is a good way to catch this rising air. Models with digital readouts are best located at eye level to make sure they’re easy to read.
  • Put in detectors at least 15 feet from combustion appliances: Some fuel-burning machines give off a tiny, harmless amount of carbon monoxide when they start. This dissipates quickly, but in situations where a CO detector is nearby, it may trigger false alarms.
  • Have detectors away from high heat and humidity: Carbon monoxide detectors have certain tolerances for heat and humidity. To limit false alarms, don’t install them in bathrooms, in harsh sunlight, near 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 suggest testing once a month and resetting to maintain 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 is chirping, whichever starts first. Then, replace the CO detector outright every 10 years or according to the manufacturer’s instructions.

How to test your carbon monoxide alarm

It only takes a minute to test your CO detector. Review the instruction manual for directions individual to your unit, with the knowledge that testing practices this general procedure:

  • Press and hold the Test button. It will sometimes need 5 to 20 seconds for the alarm to go off.
  • Loud beeping means the detector is operating correctly.
  • Let go of the Test button and wait for two quick beeps, a flash or both. If the device goes on beeping when you release the button, press and hold it again for five seconds to quiet it.

Change the batteries if the unit fails to perform as expected during the test. If replacement batteries don’t make a difference, replace the detector immediately.

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.

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 get 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 assistance from the manufacturer, or install a new detector.

What should I do if a carbon monoxide alarm starts?

Follow these steps to protect your home and family:

  • Do not dismiss the alarm. You may not be able to notice unsafe levels of carbon monoxide until it’s too late, so assume the alarm is functioning properly when it is triggered.
  • Evacuate all people and pets as quickly as possible. If you’re able to, open windows and doors on your way out to try and weaken the concentration of CO gas.
  • Call 911 or the local fire department and explain that the carbon monoxide alarm has triggered.
  • It’s wrong to think it’s safe to reenter your home when the alarm stops beeping. 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 search your home, measure carbon monoxide levels, try to find 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 recurring.

Get Support from Service Experts Heating, Air Conditioning & Plumbing

With the proper precautions, there’s no need to fear carbon monoxide poisoning in your home. In addition to installing CO alarms, it’s worthwhile to maintain your fuel-burning appliances, particularly as winter starts.

The team at Service Experts Heating, Air Conditioning & Plumbing is ready to inspect, clean, diagnose and repair problems with furnaces, boilers, water heaters and other combustion appliances. We understand what signs suggest a potential carbon monoxide leak— such as 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 & Plumbing for more information.

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