Carbon Monoxide Detectors: Ultimate Guide

Carbon monoxide (CO) is one of the most hazardous gases found in the home. Dubbed the “silent killer,” CO gas is colorless, odorless, tasteless and non-irritating, yet it can result in unconsciousness, brain damage or death. As a result, more than 400 people die as a result of carbon monoxide exposure each year, a larger fatality rate versus any other kind of poisoning.

As the weather gets colder, you seal your home for the winter and count on heating appliances to stay warm. These situations are when the threat of carbon monoxide poisoning is highest. Thankfully you can protect your family from carbon monoxide in different ways. One of the most successful methods is to put in CO detectors in your home. Check out this guide to better understand where carbon monoxide comes from and how to take full advantage of your CO sensors.

What generates carbon monoxide in a house?

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

  • Blocked up clothes dryer vent
  • Broken down water heater
  • Furnace or boiler with a broken heat exchanger
  • Closed fireplace flue while a fire is lit
  • Poorly 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 detect carbon monoxide?

No, smoke detectors do not detect carbon monoxide. In fact, they begin an alarm when they sense a certain concentration of smoke produced by a fire. Installing dependable smoke detectors lowers the risk of dying in a house fire by nearly 55 percent.

Smoke detectors are available in two primary types—ionization detectors and photoelectric detectors. Ionization detection is ideal with fast-moving fires that produce large flames, while photoelectric detectors are more suited for smoldering, smoky fires. Some newer smoke detectors include both types of alarms in a solitary unit to boost the chance of sensing a fire, no matter how it burns.

Unmistakably, smoke detectors and CO alarms are both important home safety devices. If you check the ceiling and see an alarm of some kind, you may not realize whether it’s a smoke detector or a carbon monoxide alarm. The visual discrepancy is based on the brand and model you want. Here are some factors to keep in mind:

  • Some 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 should also find a manufacture date. If the device is more than 10 years old, replace it right away.
  • Plug-in devices that use power with an outlet are generally carbon monoxide detectors be labeled saying as much.
  • Some alarms will be two-in-one, offering protection against both smoke and carbon monoxide with a different indicator light for each. Nevertheless, it can be hard to tell if there’s no label on the front, so checking the manufacturing details on the back is worthwhile.

How many carbon monoxide detectors do I need in my home?

The number of CO alarms you should have depends on your home’s size, number of floors and the number of bedrooms. Follow these guidelines to provide thorough coverage:

  • Place carbon monoxide detectors near wherever people sleep: CO gas poisoning is most prevalent at night when furnaces are running frequently to keep your home comfortable. Therefore, every bedroom should have a carbon monoxide sensor installed around 15 feet of the door. If a couple of bedroom doors are less than 30 feet apart, just one detector is sufficient.
  • Install detectors on each floor: Concentrated carbon monoxide buildup can become trapped on a single floor of your home, so do your best to have at least one CO detector on every level.
  • Install detectors within 10 feet of an attached garage door: Many people end up leaving their cars running in the garage, leading to dangerous carbon monoxide gas, even if the large garage door is completely open. A CO alarm right inside the door—and in the room over the garage—alerts you of increased carbon monoxide levels entering your home.
  • Put in detectors at the appropriate height: Carbon monoxide weighs about the same as air, but it’s commonly carried along with the hot air released by combustion appliances. Installing detectors near the ceiling is a good way to catch this rising air. Models that come with digital readouts are best placed at eye level to keep them easy to read.
  • Install detectors about 15 feet from combustion appliances: Some fuel-burning machines produce a tiny, non-toxic amount of carbon monoxide when they start. This disperses quickly, but when a CO detector is positioned too close, it might give off false alarms.
  • Install detectors away from excess heat and humidity: Carbon monoxide detectors have certain tolerances for heat and humidity. To limit false alarms, avoid installing them in bathrooms, in direct sunlight, near air vents, or close to heat-generating appliances.

How do I test/troubleshoot a carbon monoxide sensor?

Depending on the design, the manufacturer will sometimes encourage monthly testing and resetting to sustain proper functionality. Also, change out the batteries in battery-powered units twice a year. For hardwired units, replace the backup battery every year or when the alarm starts chirping, whichever comes first. Then, replace the CO detector completely after 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 sensor. Review the instruction manual for directions specific to your unit, understanding that testing follows this general procedure:

  • Press and hold the Test button. It may take 5 to 20 seconds for the alarm to start.
  • Loud beeping indicates the detector is operating correctly.
  • Release the Test button and wait for two short 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.

Replace the batteries if the unit isn’t performing 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 have to reset your unit after the alarm goes off, after testing the device or after swapping the batteries. Some models automatically reset themselves in 10 minutes of these events, while other alarms require 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 listen for a beep, a flash or both.

If you don’t get a beep or observe 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 do 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 detect unsafe levels of carbon monoxide until it’s too late, so expect the alarm is working correctly when it starts.
  • Evacuate all people and pets as soon as possible. If you can, open windows and doors on your way out to help thin out the concentration of CO gas.
  • Call 911 or your local fire department and inform them 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 may help air it out, but the root cause could still be generating carbon monoxide.
  • When emergency responders come, they will search your home, evaluate carbon monoxide levels, try to find the source of the CO leak and figure out if it’s safe to return. Depending on the cause, you might need to schedule repair services to keep the problem from reappearing.

Seek Support from Service Experts Heating, Air Conditioning & Plumbing

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

The team at Service Experts Heating, Air Conditioning & Plumbing is happy to inspect, clean, diagnose and repair issues with furnaces, boilers, water heaters and other combustion appliances. We know what signs suggest a possible carbon monoxide leak— like excess 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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