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, however it can result in unconsciousness, brain damage or death. Because of this, more than 400 people die of accidental carbon monoxide poisoning each year, a larger fatality rate compared to any other kind of poisoning.

As the weather cools down, you insulate your home for the winter and rely on heating appliances to remain warm. This is when the danger of carbon monoxide poisoning is highest. Fortunately you can safeguard your family from carbon monoxide in several ways. One of the most effective methods is to install CO detectors in your home. Use this guide to better understand where carbon monoxide can appear from and how to make the most of your CO sensors.

What causes carbon monoxide in a house?

Carbon monoxide is a byproduct whenever something combusts. Therefore, this gas can appear whenever a fuel source burns, including natural gas, propane, oil, charcoal, gasoline, woo, and more. Prevalent causes of carbon monoxide in a house may be:

Blocked up clothes dryer vent
Broken down water heater
Furnace or boiler with a broken heat exchanger
Closed fireplace flue with a lit fire
Poorly vented gas or wood stove
Vehicle sitting 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 start an alarm when they detect a certain concentration of smoke caused by a fire. Installing functional smoke detectors decreases the risk of dying in a house fire by around 55 percent.

Smoke detectors are available in two main modes—ionization detectors and photoelectric detectors. Ionization detection is ideal with fast-growing fires that produce large flames, while photoelectric detectors are more suited for smoldering, smoky fires. Some newer smoke detectors come with both kinds of alarms in a single unit to boost the chance of responding to a fire, despite how it burns.

Clearly, 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 contrast is determined by the brand and model you have. Here are some factors to keep in mind:

Some devices are properly labeled. If not, check for 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 older than 10 years, replace it right away.
Plug-in devices that extract power with an outlet are typically carbon monoxide detectors94. The device will be labeled so.
Some alarms will be two-in-one, detecting both smoke and carbon monoxide with a separate 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 smart.

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

The number of CO alarms you should have is dependent on your home’s size, the number of stories and bedroom arrangement. Follow these guidelines to ensure total coverage:

Install carbon monoxide detectors nearby sleeping areas: CO gas leaks are most common at night when furnaces are running constantly to keep your home warm. For that reason, every bedroom should have a carbon monoxide sensor installed about 15 feet of the door. If a couple of bedroom doors are less than 30 feet apart, a single alarm is enough.
Put in detectors on each floor:
Dangerous carbon monoxide buildup can become caught 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 your internal garage door: A surprising number of people unsafely leave their cars idling in the garage, resulting in dangerous carbon monoxide buildup, even when the large garage door is wide open. A CO detector just inside the door—and in the room above the garage—alerts you of heightened carbon monoxide levels entering your home.
Have detectors at the correct height: Carbon monoxide is a similar density as air, but it’s commonly carried upward in the hot air created by combustion appliances. Having detectors up against the ceiling is best to catch this rising air. Models that come with digital readouts are best located at eye level to keep them easy to read.
Add detectors at least 15 feet from combustion appliances: A few fuel-burning machines emit a tiny, non-toxic amount of carbon monoxide when they start. This dissipates quickly, but when a CO detector is positioned too close, it might lead to false alarms.
Put in detectors away from excess heat and humidity: Carbon monoxide detectors have specified tolerances for heat and humidity. To minimize false alarms, try not to install them in bathrooms, in harsh sunlight, next to air vents, or close to heat-generating appliances.

How do I test/troubleshoot a carbon monoxide alarm?

Depending on the model, the manufacturer may suggest monthly testing and resetting to ensure proper functionality. Also, replace 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 entirely after 10 years or as outlined by the manufacturer’s recommendations.

How to test your carbon monoxide alarm

All it takes is a minute to test your CO alarm. Check the instruction manual for directions unique to your unit, understanding that testing follows this general routine:

Press and hold the Test button. It will sometimes take 5 to 20 seconds for the alarm to begin.
Loud beeping signifies the detector is operating correctly.
Let go of the Test button and wait for two short beeps, a flash or both. If the device goes on 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 won't work as expected during 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 after the alarm goes off, after running a test or after swapping the batteries. Certain models automatically reset themselves in under 10 minutes of these events, while other models need a manual reset. The instruction manual will note which function applies.

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 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 nothing happens, troubleshoot your carbon monoxide alarm with help from the manufacturer, or install a new detector.

What can I do if a carbon monoxide alarm goes off?

Follow these steps to protect your home and family:

Do not ignore the alarm. You may not be able to identify 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 soon as possible. If you can, open windows and doors on your way out to attempt to thin out the concentration of CO gas.
Call 911 or your local fire department and explain 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 might still be generating carbon monoxide.
When emergency responders arrive, they will go into your home, measure carbon monoxide levels, look for the source of the CO leak and determine if it’s safe to go back inside. Depending on the cause, you might need to schedule repair services to keep the problem from recurring.

Get Support from Knochelmann Service Experts

With the right 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, especially as winter starts.

The team at Knochelmann Service Experts is happy to inspect, clean, diagnose and repair problems with furnaces, boilers, water heaters and other combustion appliances. We understand what signs could mean a possible carbon monoxide leak— like 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 Knochelmann Service Experts for more information.