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Average rating: 4.2out of 5 stars
4.2 out of 5 | 121 reviews
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1-20 of 108 reviews
1-20 of 108 reviews
Model number same but entirely DIFFERENT unit!!!
8/24/2017
Average rating:1out of5stars, based onreviews
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I bought to replace model CO400. Model no is same but unit has changed. States in description it uses 2 AA batteries (as did my previous one) but this one takes 9 volt battery and the battery door is on back instaead of front. To top it off, if you are replacing CO400 model and already have holes drilled for screws to hang, FORGET IT! The holes in this one are not spaced the same and you'll need to redrill new holes for anchors and pull out old anchors fill in the old holes!! TOTALLY RIDICULOUS!!!! They should have named with completely "different" model number to save people all this trouble. I called First Alert and they said they still make both units but it's a guess as to which one you'll get when ordering. UNACCEPTABLE!
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Good
8/8/2017
Average rating:5out of5stars, based onreviews
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My thing stopped working and had to buy a new one. I was glad I found a similar model. This works well. Not sure why buying online is always cheaper than in the store
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Model has changed
8/12/2017
Average rating:4out of5stars, based onreviews
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The CO400 shown might be the wrong one. First Alert has a new detector which looks almost the same, and has the same model number, but has some distinct differences. The older model has the battery compartment on the front where it's easy to get to. It also runs on 2 AA batteries. The chirp pattern is shown on the back of the unit, so you don't have to refer to the instruction sheet. Be aware that unless Walmart has a big stock of the older models, you will be getting one which doesn't match the one here. Otherwise, it is a decent unit and I would recommend it to anyone looking for a economical CO detector.
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Just what I was looking for
8/25/2010
Average rating:5out of5stars, based onreviews
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This is a great carbon monoxide detector-- reasonably priced, great design, not too large or too small. Would recommend.
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a very necessary product
3/25/2010
Average rating:5out of5stars, based onreviews
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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
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Just what I needed
11/17/2009
Average rating:5out of5stars, based onreviews
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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.
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Works Great in My Antique Car!
6/22/2009
Average rating:5out of5stars, based onreviews
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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.
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Good for ~3 years
8/7/2017
Average rating:4out of5stars, based onreviews
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Purchased a new CO detector after the sensor for previous one (same model) expired. Detector will work fine for ~ 3 years
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Tiny but Mighty
5/5/2011
Average rating:5out of5stars, based onreviews
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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.
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Great Product!
11/23/2012
Average rating:5out of5stars, based onreviews
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 Verified purchaser
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.
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Bad installation instructions and harder to check
12/1/2013
Average rating:3out of5stars, based onreviews
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 Verified purchaser
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).
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Great purchase!
8/30/2017
Average rating:4out of5stars, based onreviews
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 Verified purchaser
Price was fair, it does what I need, I hope. I can't really tell if it is working. I would buy it again! [This review was collected as part of a promotion.]
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Battery compartment issue and design change issue
2/24/2017
Average rating:1out of5stars, based onreviews
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 Verified purchaser
Even though it's same model number CO400, the design changed! Battery compartment changed from the front to the back, and it's very difficult to open the door.. I need to go back to the store to ask the staff to open for me. And the battery is so difficult to install. The worst part is even the screws location also changed. It's much wider than before. So I have to hammer my wall again in order to hang up the product. This's supposed not happen for same model number!!
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Product is a lifesaver.
3/7/2013
Average rating:5out of5stars, based onreviews
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 Verified purchaser
I had an older First Alert CO detector, and the alarm was beeping. I changed the battery and this did not solve the problem. I figured the older unit had aged out and needed to be replaced, but I turned off my heating system and opened windows and ventilated the house, I also heated with my wood fireplace in 21 degree weather for 2 days, and immediately bought this CO400 unit. When this alarm went off again after turning on the heating system, I called my heating contractor. The entire furnace had to be replaced as the heat exchanger was full of holes (it looked like a swiss cheese) and was allowing significant CO exhaust fumes into my hot air vents. I could have been killed. I am very happy I put in this new unit immediately.
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carbon monoxide detector
3/7/2017
Average rating:4out of5stars, based onreviews
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 Verified purchaser
I received the item on time and undamaged. that is why I have given a very good rating.
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Would have been a five but...
1/25/2017
Average rating:4out of5stars, based onreviews
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 Verified purchaser
Walmart was great. I bought this to replace one the same model number. I did not want to add new holes and wanted to use the originals mounting. Well, the batteries are now a 9v and the mounting holes are wider. They should have changed the model number in my opinion. I had to add a hole in the wall to mount it. Otherwise I am satisfied.
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Great product!
5/5/2016
Average rating:5out of5stars, based onreviews
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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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Excellent Value
1/11/2011
Average rating:5out of5stars, based onreviews
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The detector is easy to install and test. It is a great value for the peace of mind it provides.
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What every house needs
10/9/2010
Average rating:5out of5stars, based onreviews
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very good price for a well brand name.
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carbonmonoxide detector
3/14/2017
Average rating:4out of5stars, based onreviews
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 Verified purchaser
great product came fast too.
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Electrode, Comp-184640679, DC-prod-dfw3, ENV-prod-a, PROF-PROD, VER-8.12.5, SHA-f8bb53b0cf6e9da799126d89d3bcede34110bf32, CID-