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Customer Reviews for First Alert First Alert CO400 Battery-Powered Carbon Monoxide Detector

First Alert First Alert CO400 Battery-Powered Carbon Monoxide Detector

The First Alert CO400 Battery-Powered Carbon Monoxide Detector is an easy to use carbon monoxide detector that comes with one carbon monoxide alarm, a user's manual, and two AA batteries. This carbon monoxide detector features a test/silence button that silences the alarm and allows you to test its functionality. The First Alert alarm monitors and re-alarms if carbon monoxide levels persist sounding a loud 85-decibel horn. No installation is required for this carbon monoxide detector, and the attractive design allows the unit to be placed anywhere you need it. The First Alert CO400 Battery-Powered Carbon Monoxide Detector 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. 5-year limited warranty. Carbon Monoxide alarm meets UL standards.
Average Customer Rating:
4.284 out of 5
4.3
 out of 
5
(67 Reviews) 54
Open Ratings Snapshot
Rating SnapshotOverall Rating Totals
5 stars
43
4 stars
13
3 stars
3
2 stars
3
1 star
5
Customer Recommendation88%59 out of 67reviewers would recommend this product to a friend.
Customer Questions & Answers:
12 Questions | 49 Answers
Open Ratings Snapshot
Rating SnapshotOverall Rating Totals
5 stars
43
4 stars
13
3 stars
3
2 stars
3
1 star
5
Customer Reviews
Review 1 for First Alert CO400 Battery-Powered Carbon Monoxide Detector

did not work properly

12/21/2013
By
1 out of 5
1 out of 5
The battery would not stay in place rendering the device useless. The only way it works is if you hold the battery in place with your finger--not exactly practical.
Product Attributes:
Value
1 out of 5
1 out of 5
Meets Expectations
1 out of 5
1 out of 5
Recommends this product? No
+4points
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Review 2 for First Alert CO400 Battery-Powered Carbon Monoxide Detector

as expected

04/03/2014
By
5 out of 5
5 out of 5
Easy to follow instructions and installation
Product Attributes:
Value
5 out of 5
5 out of 5
Meets Expectations
5 out of 5
5 out of 5
Recommends this product? Yes
0points
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Review 3 for First Alert CO400 Battery-Powered Carbon Monoxide Detector

Just what I needed

11/17/2009
By ,
Salisbury, MD
5 out of 5
5 out of 5
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.
Product Attributes:
Value
5 out of 5
5 out of 5
Meets Expectations
5 out of 5
5 out of 5
Recommends this product? Yes
Age:35 - 44
Gender:Male
Ownership:2 - 7 weeks
Usage:Every day
+29points
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Review 4 for First Alert CO400 Battery-Powered Carbon Monoxide Detector

Works Great in My Antique Car!

06/22/2009
By ,
Florida
5 out of 5
5 out of 5
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.
Product Attributes:
Value
5 out of 5
5 out of 5
Meets Expectations
5 out of 5
5 out of 5
Recommends this product? Yes
Age:45 - 54
Gender:Female
Ownership:2 - 7 weeks
Usage:Every day
+58points
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Review 5 for First Alert CO400 Battery-Powered Carbon Monoxide Detector

Worthless

12/09/2013
By ,
Bateville
1 out of 5
1 out of 5
Battery would not stay attached into recepters and therefore didn't work.
Product Attributes:
Value
1 out of 5
1 out of 5
Meets Expectations
1 out of 5
1 out of 5
Durability
1 out of 5
1 out of 5
Recommends this product? No
Age:55 - 64
Gender:Female
Ownership:1 week or less
Usage:Never
+5points
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Review 6 for First Alert CO400 Battery-Powered Carbon Monoxide Detector

Disappointed

02/20/2014
By
2 out of 5
2 out of 5
says it has AA batteries but really takes in 9 volt
Recommends this product? No
+1point
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Review 7 for First Alert CO400 Battery-Powered Carbon Monoxide Detector

Easy installation

03/28/2014
By ,
NH
5 out of 5
5 out of 5
Works as described. priced just right.
Recommends this product? Yes
Age:65 or older
Gender:Male
Ownership:1 week or less
Usage:Every day
0points
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Review 8 for First Alert CO400 Battery-Powered Carbon Monoxide Detector

Didn't work.

11/26/2013
By ,
chicago
1 out of 5
1 out of 5
Return it to the store, didn't work.
Product Attributes:
Value
3 out of 5
3 out of 5
Meets Expectations
1 out of 5
1 out of 5
Durability
1 out of 5
1 out of 5
Recommends this product? No
Age:35 - 44
Gender:Female
+4points
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Review 9 for First Alert CO400 Battery-Powered Carbon Monoxide Detector

a very necessary product

03/25/2010
By ,
Elmira,NY
5 out of 5
5 out of 5
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
Product Attributes:
Value
5 out of 5
5 out of 5
Meets Expectations
5 out of 5
5 out of 5
Recommends this product? Yes
Age:65 or older
Gender:Male
Ownership:2 - 7 weeks
Usage:Every day
+16points
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Review 10 for First Alert CO400 Battery-Powered Carbon Monoxide Detector

Just what I was looking for

08/25/2010
By ,
Cortland, OH
5 out of 5
5 out of 5
This is a great carbon monoxide detector-- reasonably priced, great design, not too large or too small. Would recommend.
Product Attributes:
Value
5 out of 5
5 out of 5
Meets Expectations
5 out of 5
5 out of 5
Recommends this product? Yes
Age:45 - 54
Gender:Male
Ownership:2 - 7 weeks
Usage:Every day
+13points
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Review 11 for First Alert CO400 Battery-Powered Carbon Monoxide Detector

good shopping experience, product not as expected

11/21/2013
By ,
Dallas, TX
2 out of 5
2 out of 5
the product comes with a 9V battery not 2 AA as indicated in the description. There was not a good fit between the battery and the connector. I did not feel comfortable that the detector was getting power from the battery. The test was erratic. Took it back to WalMart and got the Kidde CO Alarm, operated by 3 AA batteries. The battery compartment of the Kidde is well designed and it started working immediately. May be my product was faulty, I read other reviews and people were happy with the First Alert CO400
Both products are competitively priced and the service was very good. Thank you WalMart!
Product Attributes:
Value
2 out of 5
2 out of 5
Meets Expectations
2 out of 5
2 out of 5
Durability
2 out of 5
2 out of 5
Recommends this product? No
Age:45 - 54
Gender:Male
Ownership:1 week or less
Usage:Every day
+2points
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Review 12 for First Alert CO400 Battery-Powered Carbon Monoxide Detector

Bad installation instructions and harder to check

12/01/2013
By ,
New England
3 out of 5
3 out of 5
The installation instructions include a statement and a template showing the attachment screws are spaced 2.5" apart. After I made the holes in my wall I realized that they are actually further apart than that (more like 4"). That meant I had to redo one of them to get the alarm onto the wall.
This alarm was a replacement for another brand that blinked once a minute to show that it was working. This one does not blink and only shows it is functional after the alarm-test button is pressed.
The instructions do not state clearly that after 7 years the alarm is at the end of its life and will not detect CO anymore. Other brands also fail at "end of life" but their instructions make that more obvious (all CO alarms are designed to need replacement after that time).
Product Attributes:
Value
3 out of 5
3 out of 5
Meets Expectations
3 out of 5
3 out of 5
Durability
3 out of 5
3 out of 5
Recommends this product? Yes
Ownership:2 - 7 weeks
Usage:Every day
+1point
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Read Comment (1)
Read Comments (1)
Customer Avatar
Massachusetts
Great review
Posted 02/19/2014
Thank you for your very helpful review, especially noting that that it doesn't blink periodically to indicate that it's working. That's a deal breaker for me.
0points
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Read Comment (1)
Review 13 for First Alert CO400 Battery-Powered Carbon Monoxide Detector

Hopefully it will never go off.

10/31/2013
By
5 out of 5
5 out of 5
Got two of these mainly because of the price point which was far better that anything else. Seems to be pretty good quality, although the wall anchors it came with a exceptionally cheap. Included battery (a nice feature!) was a little difficult to install but not terribly. The alarm is VERY loud but lets hope that I'll never have to hear it!
Product Attributes:
Value
5 out of 5
5 out of 5
Meets Expectations
5 out of 5
5 out of 5
Durability
5 out of 5
5 out of 5
Recommends this product? Yes
Age:25 - 34
Gender:Male
Ownership:1 week or less
+2points
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Review 14 for First Alert CO400 Battery-Powered Carbon Monoxide Detector

A good device for home

02/14/2014
By ,
Houston, tx
4 out of 5
4 out of 5
This is a good device for home in case an unknown situation happen were a silent killer like carbon monoxide will be present. This device will give you warning and alarm you of present danger
Product Attributes:
Value
4 out of 5
4 out of 5
Meets Expectations
4 out of 5
4 out of 5
Recommends this product? Yes
Age:45 - 54
Gender:Male
Ownership:1 week or less
Usage:Every day
0points
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Review 15 for First Alert CO400 Battery-Powered Carbon Monoxide Detector

Tiny but Mighty

05/04/2011
By ,
Pennsylvania
5 out of 5
5 out of 5
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.
Product Attributes:
Value
5 out of 5
5 out of 5
Meets Expectations
5 out of 5
5 out of 5
Recommends this product? Yes
Gender:Female
Ownership:2 - 7 weeks
Usage:Every day
+5points
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Review 16 for First Alert CO400 Battery-Powered Carbon Monoxide Detector

Great Product!

11/22/2012
By ,
Lewiston, ME
5 out of 5
5 out of 5
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.
Product Attributes:
Value
5 out of 5
5 out of 5
Meets Expectations
5 out of 5
5 out of 5
Recommends this product? Yes
Age:35 - 44
Gender:Male
Ownership:2 - 7 weeks
Usage:Every day
+4points
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Review 17 for First Alert CO400 Battery-Powered Carbon Monoxide Detector

What every house needs

10/08/2010
By ,
Baltimore,MD
5 out of 5
5 out of 5
very good price for a well brand name.
Product Attributes:
Value
5 out of 5
5 out of 5
Meets Expectations
5 out of 5
5 out of 5
Recommends this product? Yes
Age:45 - 54
Gender:Female
Ownership:2 - 7 weeks
Usage:Every day
+5points
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Review 18 for First Alert CO400 Battery-Powered Carbon Monoxide Detector

Easy to Install and a Great Value

04/25/2012
By ,
IN
5 out of 5
5 out of 5
I'm glad I purchased this carbon monoxide detector. It was very easy to install and already came with 2AA batteries. It was also the most inexpensive I could find - a good value. The manual is easily understood, too.
Product Attributes:
Value
5 out of 5
5 out of 5
Meets Expectations
5 out of 5
5 out of 5
Recommends this product? Yes
Age:25 - 34
Gender:Female
Ownership:1 week or less
Usage:Every day
+3points
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Review 19 for First Alert CO400 Battery-Powered Carbon Monoxide Detector
07/21/2011
By ,
Livingston, CA
5 out of 5
5 out of 5
Looking for a) inexpensive, b) reliable, c) brand-name manufacturer, d) easy to install, 3) meets all California state requirements for CO detection/alarm devices?
Look no further, this is it.
Product Attributes:
Value
5 out of 5
5 out of 5
Meets Expectations
5 out of 5
5 out of 5
Recommends this product? Yes
Age:65 or older
Gender:Male
Ownership:5 - 6 months
Usage:Every day
+3points
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Review 20 for First Alert CO400 Battery-Powered Carbon Monoxide Detector

Excellent Value

01/11/2011
By ,
Mansfield Center, CT
5 out of 5
5 out of 5
The detector is easy to install and test. It is a great value for the peace of mind it provides.
Product Attributes:
Value
5 out of 5
5 out of 5
Meets Expectations
5 out of 5
5 out of 5
Recommends this product? Yes
Age:65 or older
Gender:Male
Ownership:2 - 3 months
Usage:Every day
+3points
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1-20 of 55 total reviews
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