Carbon Monoxide Detectors: Ultimate Guide

Carbon monoxide (CO) is a potentially hazardous gas found in the home. Nicknamed the “silent killer,” CO gas is colorless, odorless, tasteless and non-irritating, however it can cause unconsciousness, brain damage or death. Consequently, more than 400 people suffer fatal carbon monoxide exposure each year, a larger fatality rate than other types of poisoning.

When the weather gets colder, you insulate your home for the winter and trust in heating appliances to keep warm. These situations are when the risk of carbon monoxide poisoning is highest. Fortunately you can safeguard your family from a gas leak in several ways. One of the most successful methods is to install CO detectors throughout your home. Use this guide to help you understand where carbon monoxide comes from and how to reap the benefits of your CO alarms.

What generates carbon monoxide in a house?

Carbon monoxide is a byproduct of something burned. Therefore, this gas is produced when a fuel source is ignited, including 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 during an active fire
  • Poorly 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. Alternatively, they begin an alarm when they detect a certain amount of smoke produced by a fire. Having functional smoke detectors reduces the risk of dying in a house fire by about 55 percent.

Smoke detectors are available in two primary forms—ionization detectors and photoelectric detectors. Ionization detection functions well with fast-growing fires that generate large flames, while photoelectric models are more suited for smoldering, smoky fires. The newest smoke detectors incorporate both kinds of alarms in a single unit to boost the chance of recognizing a fire, despite how it burns.

Obviously, smoke detectors and CO alarms are equally beneficial home safety devices. If you inspect the ceiling and notice an alarm of some kind, you won't always know whether it’s a smoke detector or a carbon monoxide alarm. The visual discrepancy is determined by the brand and model you have. Here are a few 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 look it up online. You should also find a manufacture date. If the device is more than a decade old, replace it right away.
  • Plug-in devices that draw power through an outlet are generally carbon monoxide alarms94. The device should be labeled as such.
  • Some alarms will be two-in-one, detecting both smoke and carbon monoxide with an indicator light for each. That being said, it can be tough to tell without a label on the front, so 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 should have depends on your home’s size, number of floors and bedroom arrangement. Follow these guidelines to ensure total coverage:

  • Add carbon monoxide detectors near sleeping areas: CO gas leaks are most common at night when furnaces have to run more often to keep your home comfortable. As a result, all bedrooms should have a carbon monoxide detector installed around 15 feet of the door. If multiple bedroom doors are less than 30 feet apart, just one detector is adequate.
  • Put in detectors on all floors:
    Dense carbon monoxide gas can become trapped on a single floor of your home, so do your best to have at least one CO detector on each floor.
  • 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 when the large garage door is wide open. A CO sensor right inside the door—and in the room up above the garage—alerts you of elevated carbon monoxide levels inside your home.
  • Put in detectors at the proper height: Carbon monoxide weighs about the same as air, but it’s commonly carried upward in the hot air created by combustion appliances. Putting in detectors close to the ceiling is ideal to catch this rising air. Models with digital readouts are best installed at eye level to make them easier to read.
  • Add detectors about 15 feet from combustion appliances: A few fuel-burning machines produce a tiny, non-toxic amount of carbon monoxide as they first start running. This dissipates quickly, but when a CO detector is positioned too close, it could trigger false alarms.
  • Have detectors away from excess heat and humidity: Carbon monoxide detectors have specified tolerances for heat and humidity. To reduce false alarms, don't install them in bathrooms, in direct sunlight, next to air vents, or close to heat-generating appliances.

How do I test/troubleshoot a carbon monoxide detector?

Depending on the design, the manufacturer will sometimes suggest monthly testing and resetting to maintain proper functionality. Also, change out the batteries in battery-powered units after 6 months. For hardwired units, replace the backup battery annually or when the alarm begins chirping, whichever comes first. Then, replace the CO detector outright every 10 years or as outlined by the manufacturer’s instructions.

How to test your carbon monoxide alarm

It only takes a minute to test your CO alarm. Check the instruction manual for directions unique to your unit, with the knowledge that testing follows this general procedure:

  • Press and hold the Test button. It might 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 quick 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.

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

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 replacing the batteries. Certain models automatically reset themselves in under 10 minutes of these events, while other alarms require a manual reset. The instruction manual will note which function applies.

Follow 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 notice a beep or see a flash, attempt the reset again or replace the batteries. If nothing happens, troubleshoot your carbon monoxide alarm with help from the manufacturer, or install a new detector.

What do I do if a carbon monoxide alarm starts?

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

  • Do not dismiss the alarm. You won't always be able to recognize dangerous levels of carbon monoxide until it’s too late, so expect the alarm is functioning correctly when it goes off.
  • Evacuate all people and pets as soon as possible. If possible, open windows and doors on your way out to help weaken the concentration of CO gas.
  • Call 911 or a local fire department and inform them that the carbon monoxide alarm has triggered.
  • Don't assume it’s safe to reenter your home when the alarm is no longer beeping. Opening windows and doors might help air it out, but the source could still be generating carbon monoxide.
  • When emergency responders come, they will go into your home, evaluate carbon monoxide levels, try to find the source of the CO leak and determine if it’s safe to come back inside. Depending on the cause, you might need to request repair services to prevent the problem from recurring.

Get Support from Service Experts Heating & Air Conditioning

With the appropriate precautions, there’s no need to fear carbon monoxide exposure in your home. In addition to installing CO alarms, it’s important to maintain your fuel-burning appliances, particularly as winter gets underway.

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