First Alert CO400 Battery-Powered Carbon Monoxide Detector

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  • Electrochemical sensor
  • Adds security & safety
  • 1 button tests alarm functions
  • Customers also considered

    About this item

    Important Made in USA Origin Disclaimer: For certain items sold by Walmart on Walmart.com, the displayed country of origin information may not be accurate or consistent with manufacturer information. For updated, accurate country of origin data, it is recommended that you rely on product packaging or manufacturer information.
    The First Alert CO400 Battery-Powered Carbon Monoxide Detector is an easy-to-use product that comes with one carbon monoxide alarm, a user's manual and two AA batteries. It features a test/silence button that silences the alarm and allows you to test its functionality. This detector also monitors and re-alarms if carbon monoxide levels persist, sounding a loud 85-decibel horn. No installation is required for this carbon monoxide detector alarm, and the attractive design allows the unit to be placed anywhere you need it. The alarm includes an optional wall mount with no outlet required, and is powered by two AA replaceable alkaline batteries, giving you peace of mind even during power outages. One of the main benefits of having this First Alert carbon monoxide detector is that it serves as an early warning if any carbon monoxide is leaking into your home.

    About this item

    Important Made in USA Origin Disclaimer: For certain items sold by Walmart on Walmart.com, the displayed country of origin information may not be accurate or consistent with manufacturer information. For updated, accurate country of origin data, it is recommended that you rely on product packaging or manufacturer information.

    The First Alert CO400 Battery-Powered Carbon Monoxide Detector is an easy-to-use product that comes with one carbon monoxide alarm, a user's manual and two AA batteries. It features a test/silence button that silences the alarm and allows you to test its functionality. This detector also monitors and re-alarms if carbon monoxide levels persist, sounding a loud 85-decibel horn. No installation is required for this carbon monoxide detector alarm, and the attractive design allows the unit to be placed anywhere you need it. The alarm includes an optional wall mount with no outlet required, and is powered by two AA replaceable alkaline batteries, giving you peace of mind even during power outages. One of the main benefits of having this First Alert carbon monoxide detector is that it serves as an early warning if any carbon monoxide is leaking into your home.

    The noise is loud enough for everyone in the house to hear and receive sufficient time to get out of the house. The First Alert CO400 Battery-Powered Carbon Monoxide Detector also offers stability against changing temperatures and humidity to avoid false alarms or the failure of internal circuitry. This stability also helps them accurately respond to carbon monoxide and not other common household gases or chemicals such as ammonia.
    First Alert CO400 Battery-Powered Carbon Monoxide Detector:

    • Carbon monoxide detector alarm uses electrochemical sensor for increased security
    • First Alert alarm mute feature silences detector when nuisance alarm sounds
    • Single button tests alarm functions
    • Easy front access to the battery
    • Meets UL standards
    • Battery operated, 2 AA batteries included
    • End-of-life timer, alarm chirps when it is time to replace it
    • Loud 85db alarm
    • First Alert carbon monoxide detector includes manufacturer's 5-year limited warranty

    Explore this item

    Specifications

    Cable Length: 4 Inches
    Color: Multicolor
    Battery Size: 9 V
    Mount Type: Wall
    Contained Battery Type: Alkaline
    Primary Shelf ID: 1031859
    Model: CO400
    Brand: First Alert
    Condition: New
    Material: Multi
    Manufacturer Part Number: CO400
    Features:
    • Alarm mute button
    • End of detector life timer
    • Loud 85db alarm
    Show

    Comparison Table

    Brand Image
    Alarm Type
    Alarm Type
    Power Type
    Power Type
    Digital Display
    Digital Display
    Test/Silence Button
    Test/Silence Button
    Remote Control Silence
    Remote Control Silence
    Multi-Pack Available
    Multi-Pack Available
    You are viewing
    First Alert Battery Powered Carbon Monoxide Detector CO400
     
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    2-AA Batteries
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    1-9 Volt Battery
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    Show

    Manuals & Guides

    Customer Reviews

    Customer Reviews | 95 reviews | 4.3 out of 5

    4.5 stars

    95 reviews | 4.3 out of 5

    4.5 stars

    95 reviews | 4.3 out of 5

    89%
    Would recommend to a friend
    5 stars
    62
    4 stars
    18
    3 stars
    5
    2 stars
    4
    1 stars
    6
    1-10 of 82 total reviews
    89%
    Would recommend to a friend

    Age

    Gender

    Great product!
    5/5/2016

    Customer review by Deeonwheels

    5.0 stars 5/5/2016 by Deeonwheels
    by Deeonwheels

    I had one of these carbon monoxide detectors for many years. It suddenly stopped working. It served me well for a long time so I looked for a replacement and found an exact replacement, same make and model, so I'm sure it will serve me well for many years to come also. I love the fact that I can order products on Walmart.com then pick up at the store to save shipping costs and also that "if" I do have to return or exchange something I can just take it back to the store to make my return/exchange without having to "ship" it back to a company. Thanks Walmart!

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    Deeonwheels
    Would recommend to a friend? Yes
    Just what I needed
    11/17/2009

    Customer review by Troys98

    5.0 stars 11/17/2009 by Troys98
    by Troys98

    This product is great for placement exactly where you need it. We had a new gas waterheater installed to replace an existing electric. Being that it is gas I felt the need to have this item installed so that if there ever were a problem with the waterheater we would know. I was able to install it in the room right where I wanted it without having to worry about cord placement, etc. Highly recommend.

    Was this review helpful? (45) (2)
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    Troys98
    Salisbury, MD
    Would recommend to a friend? Yes
    Age:35 - 44
    Ownership:2 - 7 weeks
    Gender:Male
    Usage:Every day
    a very necessary product
    3/25/2010

    Customer review by theexmichigander

    5.0 stars 3/25/2010 by theexmichigander
    by theexmichigander

    it is now a law that you must have a carbon monoxide detector, and if it wasn't you would be very foolish not to have them in your home. it was very easy to install, and it was very helpful that the detector came with the batteries including. it was very easy to shop Walmart Online and will be doing it again

    Was this review helpful? (25) (0)
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    theexmichigander
    Elmira,NY
    Would recommend to a friend? Yes
    Age:65 or older
    Ownership:2 - 7 weeks
    Gender:Male
    Usage:Every day
    Works Great in My Antique Car!
    6/22/2009

    Customer review by KellydaBelly

    5.0 stars 6/22/2009 by KellydaBelly
    by KellydaBelly

    I bought this detector for my antique car which I suspected was getting some exhaust in the cabin. The possibility of carbon monoxide inside the car worried me. Sure enough when we got the car out on the open road the alarm went off! So now we are having a mechanic look into the possibility an an exhaust leak. So this device works and it is a good value.

    Was this review helpful? (86) (11)
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    KellydaBelly
    Florida
    Would recommend to a friend? Yes
    Age:45 - 54
    Ownership:2 - 7 weeks
    Gender:Female
    Usage:Every day
    Does as designed
    6/30/2016

    Customer review by weekendwarriorRV

    5.0 stars 6/30/2016 by weekendwarriorRV
    by weekendwarriorRV

    Perfect - plugs into wall outlet.

    Was this review helpful? (0) (1)
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    weekendwarriorRV
    Would recommend to a friend? Yes
    Just what I was looking for
    8/25/2010

    Customer review by MrFrugal099

    5.0 stars 8/25/2010 by MrFrugal099
    by MrFrugal099

    This is a great carbon monoxide detector-- reasonably priced, great design, not too large or too small. Would recommend.

    Was this review helpful? (17) (0)
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    MrFrugal099
    Cortland, OH
    Would recommend to a friend? Yes
    Age:45 - 54
    Ownership:2 - 7 weeks
    Gender:Male
    Usage:Every day
    CO2 detector
    6/26/2016

    Customer review by jamest48

    5.0 stars 6/26/2016 by jamest48
    by jamest48
    Verified purchaser
    Verified purchaser
    Customer has been confirmed to have purchased the item from Walmart.

    Great price and easy to install

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    jamest48
    Would recommend to a friend? Yes
    Verified purchaser
    Verified purchaser
    Customer has been confirmed to have purchased the item from Walmart.
    Great price and filled the bill
    5/9/2016

    Customer review by StillTryingtoWin

    5.0 stars 5/9/2016 by StillTryingtoWin
    by StillTryingtoWin

    This is a small, unobtrusive detector. I just purchased two - one for upstairs and one for downstairs. The fit nicely above the thermostats and look like they belong there. We had to put them in when we were having our home appraised. The appraiser accepted them without question so I guess they "fill the bill" for passing state guidelines.

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    StillTryingtoWin
    Would recommend to a friend? Yes
    Tiny but Mighty
    5/5/2011

    Customer review by Revel222

    5.0 stars 5/5/2011 by Revel222
    by Revel222

    If you have a fireplace or gas appliances in your home, you should have this product. I have peace of mind now knowing I have a Carbon Monoxide Detector in the home. Easy to hang. Follow instructions about where to place it.

    Was this review helpful? (8) (0)
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    Revel222
    Pennsylvania
    Would recommend to a friend? Yes
    Ownership:2 - 7 weeks
    Gender:Female
    Usage:Every day
    Great Product!
    11/23/2012

    Customer review by megatrends

    5.0 stars 11/23/2012 by megatrends
    by megatrends
    Verified purchaser
    Verified purchaser
    Customer has been confirmed to have purchased the item from Walmart.

    Very pleased with this product and happoy it takes AA batteries, them square 9 volt ones are annoying. The installation was very easy and it came with plastic screw anchors with correct drill bit size info. Also it had a paper stencil to use as a guide for hole spacing. Installed easily, straight and perfectly the first try. Easy peasey lemon squeezy.

    Was this review helpful? (7) (0)
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    megatrends
    Lewiston, ME
    Would recommend to a friend? Yes
    Age:35 - 44
    Ownership:2 - 7 weeks
    Gender:Male
    Usage:Every day
    Verified purchaser
    Verified purchaser
    Customer has been confirmed to have purchased the item from Walmart.
    1-10 of 82 total reviews See all
    1-10 of 82 reviews

    Customer Reviews | 95 reviews | 4.3 out of 5

    Customer Reviews

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    Customer Q&A

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    Questions & Answers 14 questions
    1-3 of 14 questions

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    Back
    by an anonymous customer 5/3/2011
    8 answers
    • A. NO. You can have enough CO in the air to kill you without noticeable smoke so this serves a different alarm purpose. Other combo models do both jobs but his one is just CO.
      by OzzieSr10/17/2015
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    • A. NO. It has no means to detect smoke.
      by SylviaII10/17/2015
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    • A. No, this is separate. However, they do sell ones that are smoke detectors AND carbon monoxide detectors, Walmart has them too.
      by LoveBling10/17/2015
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    • A. A CO alarm does not replace a smoke alarm. Each alarm warns ONLY about the danger for which it was designed.
      by donever10/17/2015
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    • A. no
      by p6243w7/23/2011
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    • A. NO. While there are more expensive models on the market that provide both CO detection/alarm and smoke detection/alarm, this inexpensive unit monitors/alarms ONLY for CO.
      by LivingstonRandy7/22/2011
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    • A. Absolutely not!! You need both. Your smoke detector will not in most cases detect carbon monoxide and vice versa.
      by Revel2226/15/2011
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    • A. Yes. It replaces a wired unit.
      by Tridd3/12/2015
      Was this answer helpful? (1) (6)
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    1-3 of 14 questions See all
    1-3 of 14 questions
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