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First Alert CO400 Battery Powered Carbon Monoxide Detector: 9-Volt CO Alarm, Silences Unwanted Alarms, 7-Year Warranty
$19.99
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About this item
Highlights
- Keep your family safe with this easy to use, battery operated carbon monoxide alarm; battery powered alarms provide continuous monitoring of CO levels, even if there's a power failure
- Features an advanced electrochemical carbon monoxide sensor that accurately detects carbon monoxide levels, no matter where the detector is placed in the room
- A loud 85-decibel alarm sounds when CO levels reach dangerous levels
- To ensure complete protection make sure to place one on each level of your home and in each bedroom
- 5-7 year limited warranty; equipped with end-of-life signal chirp, so you know when it's time to replace the unit for safety
- All First Alert CO alarms are rigorously tested to meet UL standards
Description
The First Alert CO400 Carbon Monoxide Alarm utilizes an electrochemical carbon monoxide sensor to monitor your space for a carbon monoxide threat. The battery-powered design doesn't require an electrician; simply insert the included 9-volt battery, and the carbon monoxide detector is ready to go.
The advanced electrochemical CO sensor detects carbon monoxide leaks from multiple sources, such as faulty fuel-burning appliances, blocked chimneys, and generators running inside or too close to homes. When CO levels become elevated, a loud 85-decibel alarm alerts you to the threat.
Because CO evenly distributes itself, it's important to have a CO detector on every level and in every bedroom of your home. Designed to be simple to use, the CO detector has just one button that silences or tests the unit, as well as an end-of-life timer that lets you know when it's time to replace the device.
The advanced electrochemical CO sensor detects carbon monoxide leaks from multiple sources, such as faulty fuel-burning appliances, blocked chimneys, and generators running inside or too close to homes. When CO levels become elevated, a loud 85-decibel alarm alerts you to the threat.
Because CO evenly distributes itself, it's important to have a CO detector on every level and in every bedroom of your home. Designed to be simple to use, the CO detector has just one button that silences or tests the unit, as well as an end-of-life timer that lets you know when it's time to replace the device.
Dimensions (Overall): 3.38 Inches (H) x 4.87 Inches (W) x 1.56 Inches (D)
Weight: .45 Pounds
Features: Silences Unwanted Alarms
Package Quantity: 1
Requires Hardwired Installation: No
Battery: 1 9-Volt Alkaline, Required, Included
Warranty: 7 Year Limited Warranty. To obtain a copy of the manufacturer's or supplier's warranty for this item prior to purchasing the item, please call Target Guest Services at 1-800-591-3869
TCIN: 11134898
UPC: 029054013101
Item Number (DPCI): 085-14-0248
Origin: Imported
If the item details aren’t accurate or complete, we want to know about it.
Shipping details
Estimated ship dimensions: 8.39 inches length x 6.66 inches width x 2.72 inches height
Estimated ship weight: 0.474 pounds
Return details
This item can be returned to any Target store or Target.com.
This item must be returned within 90 days of the date it was purchased in store, shipped, delivered by a Shipt shopper, or made ready for pickup.
See the return policy for complete information.
Q: Will this carbon monoxide detector work even if battery is out?
submitted by Bubba - 7 years ago
A: Thank you for your question. This is a battery powered unit that will not function without batteries.
submitted byFirstAlertProductExpert - 4 years agoBrand expertA: No. It has to have 9v in it
submitted by - 5 years ago
Q: Can it sit on a table?
submitted by Kathy rieth - 1 year ago
A: Yes. It can stand up on its own (although not the most stable if on a place that gets bumped or moved)
submitted byJumpman23 - 10 months ago
Q: Does this CO detector have a LED to show it is powered up with battery ?
submitted by Phantom of darkness - 2 years ago
A: No, you have to press the Test button.
submitted byRudolph - 2 years ago
Q: what is the lowest amt it will detect?
submitted by Cilla - 3 years ago
A: Thank you for your question. If the alarm is exposed to 400 ppm of CO, It must alarm between 4 and 15 minutes. If you have any additional questions, please don't hesitate to reach out directly to our Support Team at First Alert at at 1 (800)-323-9005.
submitted byFirstAlertProductExpert - 3 years agoBrand expert
Q: Does it works when ice fishing in tents?
submitted by allaboutevecapricorn - 4 years ago
A: Thank you for your question. We recommend not placing in areas where temperature is colder than 40˚ F (4˚ C) or hotter than 100˚ F(38˚ C).
submitted byFirstAlertProductExpert - 4 years agoBrand expert
Q: What size batteries does it take?
submitted by Tina R - 5 years ago
A: This particular model takes 9 volt
submitted by - 5 years ago
Q: How does this attach to the wall?
submitted by JH - 6 years ago
A: Two screws in the wall and it slides onto them
submitted by - 5 years ago
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5 out of 5 stars with 1 ratings
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4.2 out of 5 stars with 185 reviews
quality: 3.46 out of 5
value: 3.71 out of 5
75% would recommend
54 recommendations
1 out of 5 stars
Thumbs down graphic, would not recommend
10 August, 2025Verified purchase
Use a knife to remove battery door, no thanks!
The battery compartment is so difficult to remove that I'm returning this item. It says "easy slide open" or something similar in the directions. Nope! I found several online reviews saying they need to use a knife to remove the battery door. Not acceptable.
4 out of 5 stars
Thumbs up graphic, would recommend
12 July, 2025Verified purchase
Much needed
I owned the brand pryer and purchased this one not k owing it was battery operated
1 out of 5 stars
Thumbs down graphic, would not recommend
1 May, 2025Verified purchase
Not accurate and turns on too much.
The sound alarm turns on after being installed two mintues. There's no gas leak smell and it continues to turn on and the alarm sound is really loud.
1 out of 5 stars
Thumbs down graphic, would not recommend
24 February, 2025Verified purchase
not accurate
sounds alarm every now & then when there is not carbon monoxide present, very frustrating device.
1 out of 5 stars
Thumbs down graphic, would not recommend
9 November, 2024Verified purchase
Terrible design
Cannot get the battery door open!! Seriously BAD design! Back it goes
1 out of 5 stars
Thumbs down graphic, would not recommend
3 November, 2024Verified purchase
Does not last long!
Purchased in March 2024 stopped working October 2024 what a scam
1 out of 5 stars
Thumbs down graphic, would not recommend
20 August, 2024
Stopped Workomg
Bought in March 2023 and stopped working Aug 2024.
5 out of 5 stars
Thumbs up graphic, would recommend
15 July, 2024Verified purchase
Really great for the price!
It was really easy to put together and there was a battery included. I live in an apartment and wanted extra assurance that I'm safe. Also super easy to put up!
5 out of 5 stars
Thumbs up graphic, would recommend
26 April, 2024Verified purchase
Good brand. Good price.
Perfect replacement for our previous CO detector that died after 7 years.
1 out of 5 stars
Thumbs down graphic, would not recommend
12 April, 2024Verified purchase
Didnt Alert to Gas Leak
Didn’t catch a gas leak in our kitchen. Would not recommend
5 out of 5 stars
Thumbs up graphic, would recommend
29 January, 2024Verified purchase
Great alarm
The price was right. The alarm has a nice profile.
1 out of 5 stars
Thumbs down graphic, would not recommend
21 December, 2023
Difficult to Set Up
The battery door is impossible to open. It should not be this inconvenient to even set up.
5 out of 5 stars
Thumbs up graphic, would recommend
30 August, 2023
Buy it
Bought this after a scare! Everyone needs one of these in their home
1 out of 5 stars
Thumbs down graphic, would not recommend
17 May, 2023
Garbage - Didn't work
Don't buy this garbage. Didn't work stright out of the package!
1 reply from FirstAlertProductExpert team - 2 years ago
Thank you for your feedback, Doug. We apologize for any inconvenience. This detector comes with a 7-year warranty. We would like to talk to you about how we can help. Please don’t hesitate to reach out to us at First Alert at 1 (800)-323-9005 to further trouble shoot or replace the unit.
2 out of 5 stars
Thumbs down graphic, would not recommend
16 March, 2023
Battery door hard to open & super loud
The battery door was nearly impossible to open. The instructions say to press the test button after installing battery and the “chirp” was so loud I lost my hearing for an hour.
1 reply from FirstAlertProductExpert team - 3 years ago
Thank you for your feedback. We apologize for any inconvenience. We’re here to help. We would like to talk to you further to better understand your experience. Please don’t hesitate to reach out to us at First Alert at 1 (800)-323-9005.
4 out of 5 stars
Thumbs up graphic, would recommend
28 February, 2023Verified purchase
Carbon monoxide detector
good quality and it was in stock when I needed it.
5 out of 5 stars
Thumbs up graphic, would recommend
10 December, 2022
Good!
This was the exact replacement and came with the battery, so it was very easy to put up quickly.
5 out of 5 stars
Thumbs up graphic, would recommend
9 August, 2022Verified purchase
Easy to use
Battery operated and easy to relocate as needed.
5 out of 5 stars
25 June, 2022
2015-2022
Just wanted to post regarding the life of the unit. It started chirping 5 times the other night. I got it a new battery and same thing. The back states that 5 chirps means end of product life, so that feature works. Product is marked 2/2015 and it chirped a few days ago and I think had a battery in it the majority of that time. No issues with it while it was working. I couldn’t even say if I changed the battery on it (which is also a feature) so it isn’t a battery-sucker.
4 out of 5 stars
Thumbs up graphic, would recommend
23 March, 2022Verified purchase
Works well
Alerted me when I didnt expect it to go off. And it was justified.