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, but it can lead to unconsciousness, brain damage or death. Consequently, more than 400 people die as a result of carbon monoxide poisoning each year, a steeper fatality rate than any other kind of poisoning.

When the weather gets colder, you seal your home for the winter and rely on heating appliances to remain warm. This is where the risk of carbon monoxide exposure is highest. Thankfully you can protect your family from a gas leak in different ways. One of the most successful methods is to add CO detectors around your home. Try this guide to better understand where carbon monoxide comes from and how to take full advantage of your CO sensors.

What causes carbon monoxide in a house?

Carbon monoxide is a byproduct of something burned. Because of this, this gas is generated when a fuel source is ignited, including natural gas, propane, oil, charcoal, gasoline, woo, and more. Prevalent causes of carbon monoxide in a house include:

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

Do smoke detectors sense carbon monoxide?

No, smoke detectors do not detect carbon monoxide. Alternatively, they start an alarm when they sense a certain amount of smoke generated by a fire. Possessing functional smoke detectors reduces the risk of dying in a house fire by about 55 percent.

Smoke detectors are offered in two primary modes—ionization detectors and photoelectric detectors. Ionization detection is ideal with fast-growing fires that produce large flames, while photoelectric detection is more suited for smoldering, smoky fires. The newest smoke detectors include both types of alarms in one unit to increase the chance of responding to a fire, regardless of how it burns.

Clearly, smoke detectors and CO alarms are both beneficial 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 contrast is determined by the brand and model you have. Here are some factors to keep in mind:

  • Most devices are visibly labeled. If not, look for a brand and model number on the back of the detector and locate it online. You should 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 through an outlet are generally carbon monoxide will be labeled saying as much.
  • Some alarms are two-in-one, sensing both smoke and carbon monoxide with an indicator light for each. Still, it can be hard to tell with no label on the front, so reviewing 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 provide complete coverage:

  • Add carbon monoxide detectors around wherever people sleep: CO gas poisoning is most prevalent at night when furnaces must run constantly to keep your home comfortable. As a result, all bedrooms should have a carbon monoxide detector installed about 15 feet of the door. If multiple bedroom doors are less than 30 feet apart, one detector is sufficient.
  • Put in detectors on all floors: Concentrated carbon monoxide gas can become trapped on a single floor of your home, so make sure you have at least one CO detector on every level.
  • Install detectors within 10 feet of the internal garage door: A lot of people accidentally leave their cars on in the garage, resulting in dangerous carbon monoxide buildup, even when the large garage door is fully open. A CO sensor immediately inside the door—and in the room above the garage—alerts you of heightened carbon monoxide levels entering your home.
  • Have 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. Installing detectors close to the ceiling is best to catch this rising air. Models with digital readouts are best installed at eye level to make them easier to read.
  • Install detectors at least 15 feet from combustion appliances: Some fuel-burning machines emit a tiny, non-toxic amount of carbon monoxide at startup. This breaks up quickly, but if a CO detector is positioned too close, it may lead to 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 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 monthly testing and resetting to maintain proper functionality. Also, swap out the batteries in battery-powered units every six months. For hardwired units, replace the backup battery once a year or when the alarm starts chirping, whichever starts first. Then, replace the CO detector outright after 10 years or as outlined by the manufacturer’s instructions.

How to test your carbon monoxide alarm

All it takes is a minute to test your CO alarm. Review the instruction manual for directions specific to your unit, understanding that testing uses this general procedure:

  • Press and hold the Test button. It might take 5 to 20 seconds for the alarm to go off.
  • Loud beeping signifies the detector is operating 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 quiet it.

Change the batteries if the unit fails to perform as expected after the test. If replacement batteries don’t change anything, replace the detector entirely.

How to reset your carbon monoxide alarm

You only need to reset your unit after the alarm goes off, after running a test or after swapping the batteries. A few models automatically reset themselves in 10 minutes of these events, while other alarms require a manual reset. The instruction manual should 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 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 assistance from the manufacturer, or install a new detector.

What do I do if a carbon monoxide alarm starts?

Listen to these steps to protect your home and family:

  • Do not disregard the alarm. You won’t always be able to detect hazardous levels of carbon monoxide until it’s too late, so expect the alarm is working correctly 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 help weaken the concentration of CO gas.
  • Call 911 or your local fire department and report that the carbon monoxide alarm has started.
  • It’s wrong to think it’s safe to reenter your home when the alarm stops beeping. Opening windows and doors can help air it out, but the root cause may still be generating carbon monoxide.
  • When emergency responders arrive, they will go into your home, measure carbon monoxide levels, try to find the source of the CO leak and determine 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.

Find Support from Service Experts Heating, Air Conditioning & Plumbing

With the appropriate precautions, there’s no need to fear carbon monoxide inhalation in your home. In addition to 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 happy 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— such as excess 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 Service Experts Heating, Air Conditioning & Plumbing for more information.

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