Questions About Carbon Monoxide

1) What is Carbon Monoxide?

Carbon monoxide (CO) is an invisible, odorless gas. It is a common by-product of incomplete combustion, produced when fossil fuels like wood, coal, charcoal, gasoline, kerosene, natural gas, or oil burn.

2) Where does Carbon Monoxide come from?

Carbon Monoxide can be produced by gas or oil appliances like a furnace, clothes dryer, range, oven, water heater, or space heater. When appliances and vents work properly, and there is enough fresh air in your home to allow complete combustion, the trace amounts of CO produced are typically not dangerous. These conditions can cause CO levels to rise quickly:

• Appliance malfunction, i.e. the heat exchanger on your furnace cracks.
• Vent, flue, or chimney is blocked by debris or even snow.
• Fireplace, wood burning stove or charcoal grill is not properly vented.
• Vehicle is left running in an attached garage and CO seeps into the house.
• Several appliances are running at the same time, competing for limited fresh air. This can cause incomplete combustion and produce CO, even if all appliances are in good working condition.

3) Why is Carbon Monoxide dangerous?

Because CO robs your blood of oxygen. When you inhale carbon monoxide, it bonds with the hemoglobin in your blood, displacing life-giving oxygen. This produces a toxic compound in your blood called "Carboxyhemoglobin" (COHb). Over time, exposure to CO can make you sick. Victims exposed to enough carbon monoxide can suffer brain damage, or even die. According to the Journal of the American Medical Association (JAMA), 1500 people die each year because of CO poisoning, and another 10,000 become ill. Since you can't see, smell, or taste carbon monoxide, it can make you sick before you even know it's there.

4) What are the symptoms of Carbon Monoxide poisoning?

Mild exposure: Slight headache, nausea, vomiting, fatigue, flu-like symptoms Medium exposure: Throbbing headache, drowsiness, confusion, fast heart rate. Extreme exposure: Convulsions, unconsciousness, heart and lung failure. Exposure can lead to brain damage and death.

5) Is Carbon Monoxide lighter than air?

Carbon monoxide weighs about the same as air and distributes evenly throughout the room and house. When installing a CO alarm, choose a location where the alarm will stay clean, and out of the way of children or pets. See User's Manual for specific installation requirements.

6) What level of CO will hurt me or my family?

This is different for each person. Since it is a poison, it affects everyone at different levels. Age, size, and health are other factors that can determine the effect CO has on them. You should contact your own physician for advice regarding this question. Everyone is at risk from carbon monoxide poisoning, but some people are more vulnerable. Unborn babies, infants, children, seniors, and people with heart or lung problems are at higher risk from CO poisoning.

7) What does "Move to Fresh Air" mean?

The "Move to Fresh Air" mean printed on the face of newer CO alarms is a reminder to move all family members to an area with fresh air if the alarm sounds. You should not unplug or move the CO alarm itself.

8) What should I do when the CO alarm sounds?

Silence the alarm. Call your emergency services, fire department, or 911. Move everyone immediately to fresh air-outdoors or by an open door or window. Do a head count to check that all persons are accounted for. Do not re-enter the premises or move away from the open door or window until the emergency services responder has arrived, the premises have been aired out, and your CO alarm remains in its normal condition.

9) Why didn't the emergency responder find CO after an alarm?

If your carbon monoxide alarm went off, it detected CO. Here are some reasons why a responder may not find CO during an investigation:

• Carbon monoxide dissipated in fresh air. If windows and doors open before a responder arrived, the same concentration of CO may no longer be present. Be safe first, the responder can try to recreate the conditions.
• The alarm may have been caused by an on-again, off-again problem. CO alarms measure exposure over time, so the exact conditions that cause an alarm may be difficult to duplicate in an investigation.

Questions About CO Alarms

1) Will CO alarms detect gas leaks?

No, this is a CO Alarm and it reacts to carbon monoxide only. To detect gas, you need a gas detector.

2) How long does a Carbon Monoxide Alarm last?

First Alert alarms are warranted for 5 years, then it should be replaced with a new CO Alarm. SensorPack Modules and batteries should be replaced as needed for those alarms requiring them.

3) Where should I install my First Alert residential Carbon Monoxide Alarm?

Install at least one CO Alarm near or in each separate sleeping area. For added protection, install an additional CO Alarm at least 15-20 feet away from the furnace or fuel burning heat sources. Also, locate CO Alarms at least 10 feet from sources of humidity like bathrooms and showers. In two story houses, install one CO Alarm on each level of the home. If you have a basement, install that CO Alarm at the top of the basement stairs.

4) Is there anywhere I shouldn't install my Carbon Monoxide Alarm?

DO NOT locate a CO Alarm in garages, kitchens, furnace rooms, or in any extremely dusty, dirty, humid, or greasy areas. Do not place units in direct sunlight, or areas subjected to temperature extremes. These include unconditioned crawl spaces, unfinished attics, uninsulated or poorly insulated ceilings, and porches. CO Alarms should not be located in outlets covered by curtains or other obstructions. Do not place in turbulent air-near ceiling fans, heat vents, air conditioners, fresh air returns, or open windows. Blowing air may prevent CO from reaching the CO sensors.

5) Can First Alert Carbon Monoxide detectors be used in RVs?

No. Our carbon monoxide detectors are designed for residential use only, not for recreational vehicles, automobiles, airplanes, or marine vehicles.

6) Is one CO Alarm enough for my home? If not, how many should I have?

Install a CO Alarm on every level of your home. If you install only one CO Alarm in your home, locate it near or in your bedroom.

7) How high should I install my CO Alarm?

For ease of viewing you can locate the alarm about 5 feet off the floor. Carbon monoxide weighs about the same as air and distributes evenly throughout the room/house. Choose a location where the CO Alarm will stay clean and out of the way of children or pets. See your User's Manual for specific installation requirements.

8) Why does my CO Alarm sound when there doesn't seem to be a problem?

Remember, CO is an odorless, colorless gas. If your carbon monoxide alarm went off, it detected potentially harmful amounts of CO. Make sure no one has any symptoms of CO poisoning. Here are a few situations that may cause alarms:

• The CO alarm needs to be relocated. The CO alarm should be located 15-20 feet away from all fossil fuel burning sources like furnaces and stoves. It should be located 10 feet away from sources of humidity like showers.
• Fossil fuel burning appliances not burning fuel completely. Check pilot lights/flames for blue color. Appearance of yellow or orange flames indicates incomplete combustion-a source of carbon monoxide.
• The type and age of the CO Alarm. If your CO alarm is one with a Sensor Pack Module: The SensorPack Module should be replaced after 2 years of use. If you have a plug-in alarm: Was the unit unplugged and then plugged in again?

9) Where can I buy a replacement SensorPack Module?

SensorPack Modules are available at many local retail stores. If your store does not carry them, you can purchase a replacement directly from First Alert. The current replacement SensorPack Module is Model FCD1R. It will fit all of our CO detectors using SensorPack Modules. These modules last an average of 2 to 3 years.  

10) Is the date on the SensorPack Module an expiration date?

No, it's a Best if Installed by date. You need to replace the SensorPack Module every 2 to 3 years.

11) How long does it take for the SensorPack Module to reset?

SensorPack Modules are designed to clear in fresh air in about 1 to 3 hours. The actual time will depend on how much CO the sensor has been exposed to. The sensor is designed to react to CO like your blood does. The higher the exposure, the longer the reset time.

12) Why does the red light flash?

Do I have CO? No. The red light flashes to show the CO Alarm is receiving battery power.

13) Can I unplug the CO alarm to silence or reset it?

No! Plug-in alarms will only reset when it is receiving electricity. Press and hold the Test/Silence button for 5 seconds to quiet the alarm while ventilating. You may have to do this numerous times to give the alarm time to reset.

14) Can you reset a plug-in CO Alarm with the Test/Silence button?

No, that only tests or silences the CO Alarm. To reset the alarm, the unit needs fresh air and time to burn the contamination off the sensor. Push and hold the silence button for 5 seconds to silence the alarm while contamination is being burned off the sensor. You may need to do this a number of times to give the alarm time to reset.

15) On my plug-in Carbon Monoxide Alarm, why is the green power light flashing?

Every time there is a power outage, brownout, or surge the alarm goes through a power up cycle. The flashing should stop after 5 minutes, then the light will stay a steady green.

16) How do I test the CO Alarm?

Press and hold the Test Button on the front of the alarm until the alarm sounds. Be sure you hold the button down long enough. It can take up to 20 seconds for the alarm to respond to the button.

17) Can the Carbon Monoxide Alarm be tested any other way besides pressing the test button?

The test/silence button is the only proper way to test the CO Alarm. NEVER use vehicle exhaust! Exhaust causes permanent damage and voids your warranty. For alarms with the remote control test/silence, you can also use your household IR (standard television) remote control to test or silence the alarm.

18) Can I remove the battery from the CO Alarm to silence or reset it?

NO! The CO Alarm is designed to reset automatically. Use the Test/Silence Button to quiet the alarm while the alarm is resetting.

19) Why does the horn "chirp" once a minute on my battery powered CO Alarm?

The battery may be low or weak. Is the Battery Light yellow or green? If it's yellow, it means the battery is low. Replace it with a new battery.

20) What does the SERVICE light mean on the FCD3 and SC01 units?

First, check the User's Manual to make sure the correct 9-volt battery is installed. If that's OK, then the problem is with the sensor and the detector will have to be replaced.

21) Is there an audible and visual warning for carbon monoxide presence?

An 85-decibel alarm will sound when carbon monoxide reaches the alarm level. Some Carbon Monoxide Alarms have lights to indicate if the alarm is in early warning or full alarm. Check your User's Manual to determine how your CO Alarm works.

22) Why should I leave the CO Alarm plugged in all year?

CO problems can happen at any time. Remember, your furnace or space heaters aren't the only source of CO. Gas ranges, water heaters, dryers, charcoal grills, or vehicles left running in an attached garage can all cause CO problems.

23) Have First Alert CO Alarms ever been recalled?

There has never been a recall on any of our CO Alarms.

24) How long will the batteries last in the alarm?

Actual battery service life depends on the Smoke or CO Alarm and the environment in which it is installed. All the batteries specified in the users manual are acceptable replacement batteries. Regardless of the manufacturer’s suggested battery life, you MUST replace the battery immediately once the unit starts “chirping” (the “low battery warning”).

25) I have a Carbon Monoxide alarm that states that you can use your TV remote control to silence or test this alarm, but it will not operate.

If the Alarm does not respond to your remote control, there may be an obstruction between you and the Alarm. You may be standing too far away, or your remote control may not be compatible.

DISCLAIMER: Check your state and local codes before starting any project. Follow all safety precautions. Every effort has been made to ensure the accuracy and safety of the information in this document. Neither NRHA, any contributor nor Aubuchon Hardware can be held responsible for damages or injuries resulting from the use of the information in this document.

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