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FIRST ALERT BRK SC9120FF Hardwired Smoke and Carbon Monoxide (CO) Detector with Battery Backup, 1 pack , White

4.7 4.7 out of 5 stars 25,272 ratings
Amazon's Choice highlights highly rated, well-priced products available to ship immediately.
Amazon's Choice in Smoke & Carbon Monoxide Alarms by FIRST ALERT

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1-Pack
Detector

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About this item

  • Keep your family safe with this hardwired smoke and carbon monoxide alarm; The battery backup means constant monitoring, even if there's a power failure
  • Features an electrochemical carbon monoxide sensing technology as well as an ionization sensor for smoke detection.
  • Indicator lights on the face of the unit display the presence of smoke or carbon monoxide, while an 85 decibel siren provides a clear, loud warning upon detection
  • Can connect to other compatible BRK or First Alert detectors, to ensure all alarms will sound when threat is detected
  • Simple to use, with a single test/silence button, and side load battery compartment; Tamper resistant locking brackets and universal mounting brackets make installation easy
  • Rigorously tested to meet UL standards
  • Faster turnarounds on job sites with the easy-to-install, most-trusted alarms in home safety
  • First Alert has been the most trusted brand in home safety since launching the first residential smoke alarm in 1958 (Based on a First Alert Brand Trust Survey in February 2018)
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Customer ratings by feature

Safety Features
4.9 4.9
Easy to install
4.6 4.6
Motion detection
4.5 4.5
Battery life
4.3 4.3

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FIRST ALERT BRK SC9120FF Hardwired Smoke and Carbon Monoxide (CO) Detector with Battery Backup, 1 pack , White
FIRST ALERT BRK SC9120FF Hardwired Smoke and Carbon Monoxide (CO) Detector with Battery Backup, 1 pack , White
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First Alert BRK SC9120B-6 Hardwired Smoke and Carbon Monoxide Detector (CO) with Battery Backup. 6-Pack , White
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Price$39.31-5% $44.96
Typical:$47.12
$42.99-16% $46.13
List:$54.99
$38.29$216.80
Delivery
Get it as soon as Monday, Apr 1
Get it as soon as Monday, Apr 1
Get it as soon as Monday, Apr 1
Get it as soon as Monday, Apr 1
Get it as soon as Monday, Apr 1
Get it as soon as Monday, Apr 1
Customer Ratings
Easy to install
4.6
4.4
3.8
4.5
4.6
Battery life
4.3
4.4
3.9
4.2
4.3
Value for money
4.0
4.0
3.8
4.2
4.0
Tech Support
4.1
3.0
4.1
Sold By
Amazon.com
Amazon.com
X-Sense US
Amazon.com
Amazon.com
Amazon.com
power source
Battery Powered,Hardwired
Corded Electric
AC
Hardwired
Battery Powered
Battery Powered
sensor type
electrochemical,ionization
Ionization
Photoelectric, Electrochemical
Photoelectric, Electrochemical
Photoelectric, Electrochemical
Electrochemical
style
Hardwired Alarm
Smoke, CO
Hardwired Interconnected Model (with Voice Location)
Updated Model
Updated Model
Hardwired Alarm
alarm
Audible
Smoke, CO
Fire, Smoke, Carbon Monoxide
Combination Smoke and Carbon Monoxide Alarm
Audible
weight
0.5 pounds
0.56 pounds
0.45 pounds
1 pounds
0.7 pounds

From the manufacturer

First Alert
What is carbon monoxide?

Common sources of Carbon Monoxide

Furniture

Dryer Vent

Chimney

What does the beep mean?

4 beeps and a pause

1 beep every minute

5 beeps every minute

Emergency: Carbon monoxide has been detected. Move to fresh air and call 911.

Low battery: It's time to replace the batteries in your carbon monoxide alarm.

End of life: It's time to replace your carbon monoxide alarm.

Recommended alarm placement

Looking for specific info?

Product information

Technical Details

Additional Information

Warranty & Support

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Product Warranty: For warranty information about this product, please Click here [PDF ]

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FIRST ALERT BRK SC9120FF Hardwired Smoke and Carbon Monoxide (CO) Detector with Battery Backup, 1 pack , White


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Product Description

The BRK SC9120B hardwire combination smoke and carbon monoxide alarm detects two hazards with one simple unit. Carbon monoxide (CO) is a colorless, odorless, deadly gas. It can be emitted by sources including gas or oil furnaces, gas clothes dryers, water heaters, fireplaces, wood stoves, charcoal grills, gas ranges, and space heaters. A clogged chimney, improper venting, and attached garages can also cause carbon monoxide accumulation. The BRK SC9120 hardwire combination smoke and CO alarm with battery backup includes these features: Quick plug in power connector for easy installation, 120 volt AC inter connectable (with maximum 18 compatible devices 12 other compatible smoke alarms + 6 compatible devices like bells, horns, repeaters and door closers. If one unit triggers an alarm, all smoke alarms in the series will sound. Single test/silence button which both silences a non-threatening alarm or low battery warning and allows you to test the unit's functionality. Automatically performs internal test of functionality. Latching alarm indicator which automatically identifies which unit initiated the alarm. Battery drawer lock and mounting bracket lock for tamper resistance. AC power indicator and alarm indicator light. Low battery warning "chirp" and missing battery tab. 9 volt battery backup for peace of mind during power outages. All BRK Electronics carbon monoxide alarms are listed to UL Safety Standard 2034 for residential carbon monoxide alarms. Includes 9 volt backup battery. 10 year limited warranty. Includes: One combination smoke and CO alarm, one 9 volt battery, and user’s manual.Hardwired combination CO smoke alarm features battery backup for constant monitoring.

Customer reviews

4.7 out of 5 stars
4.7 out of 5
25,272 global ratings

Customers say

Customers are happy with the quality, performance and value of the gas smoke fire alarm. For example, they say it's a reliable brand, works well and is good value for money. Customers are also impresseded with the ease of installation, fit, and ease of replacement. That said, some complain about the noise and battery life.

AI-generated from the text of customer reviews

1,014 customers mention976 positive38 negative

Customers find the installation process of the gas smoke fire alarm to be easy. They mention that it's super easy to install, does what it needs, and is easy to plug in existing wiring.

"Install was super easy. Tested fine. And looks nice. I took the picture in low light to show the green light. Reliable brand...." Read more

"...All three of these went up easily and mounted to the old ring attached to the ceiling. Just flawless. All three tested perfectly...." Read more

"...For hardwired detectors these were as easy as lights to install and were solid replacements for the existing ones...." Read more

"You can't go wrong with First Alert. Easy to install and the back plate is the same size as 11 years ago, so no repainting is necessary." Read more

725 customers mention516 positive209 negative

Customers like the quality of the gas smoke fire alarm. They say it's well made, reliable, and a must for every home. Some mention that the alarms have zero issues and were manufactured fairly recently. Overall, customers are satisfied with the quality and performance of the product.

"...I took the picture in low light to show the green light. Reliable brand. I'll be buying another one too replace my other old smoke detector." Read more

"...To meet code we got these because they have both the CO and smoke detection...." Read more

"...Had to look up the three beeps. It indicates that the CO sensor "has malfunctioned". Everything I can find says it means to throw it away...." Read more

"...I'm glad these are dual function as California requires carbon monoxide detectors in the house. My old ones were only smoke detectors...." Read more

701 customers mention614 positive87 negative

Customers like the performance of the gas smoke fire alarm. They mention that it works well, is well-made, and has zero issues. Some say that the test functions work clearly and loudly, and that it is hardwired.

"Install was super easy. Tested fine. And looks nice. I took the picture in low light to show the green light. Reliable brand...." Read more

"...Just flawless. All three tested perfectly. Highly recommend." Read more

"Easy to install and works great" Read more

"These detectors worked great to replace my old ones that had stopped working. They were doing the 3 beeps meaning they needed to be replaced...." Read more

350 customers mention316 positive34 negative

Customers appreciate the value of the gas smoke fire alarm. They mention that it has a good price, is a cheaper replacement product, and is able to fit in with their home decor. Some say that the price seems good for 3 alarms and that they saved money by purchasing it.

"Great price. Easy to install. Used to replace older units" Read more

"...detectors are so expensive but these turned out to be the most cost effective option, they were super easy to install, AND they came with a duracell..." Read more

"Easy to install. Good value." Read more

"Good, cheaper replacement products. Worked better than the ones at costco, which for some reason didn't work. Glad it wasn't just me." Read more

218 customers mention204 positive14 negative

Customers find the replacement of the gas smoke fire alarm to be easy. They mention that it takes just a few minutes to replace the old one, without having to rewire. Some say that the old unit arrived with a dead battery and that it was easy to retrofit to the same model's base. Overall, most are satisfied with the ease of replacement.

"...these were as easy as lights to install and were solid replacements for the existing ones. I’d recommend these (I got them on sale)." Read more

"...Perfect form/fit/function fit. No need to change baseplate. Took me longer to go find the step stool than it did to do the actual part change." Read more

"...These new units have been a very easy replacement since they use the same mounting ring and wiring harness as my original units...." Read more

"...It did! So when the old one went bad, it was a super-quick swap out. And now we have CO2 protection too...." Read more

141 customers mention132 positive9 negative

Customers are satisfied with the fit of the gas smoke fire alarm. They mention that it fits right into existing housing, without the need for the included wires or new wall plate. Some say that the replacement detector fits into the original bracket and connects to the existing wiring. Overall, most are happy with the performance and ease of installation of this product.

"...Easy to install and the back plate is the same size as 11 years ago, so no repainting is necessary." Read more

"...Perfect form/fit/function fit. No need to change baseplate. Took me longer to go find the step stool than it did to do the actual part change." Read more

"...These devices fit perfectly in the existing wiring harness." Read more

"Retrofit an old smoke detector with this on.Fit perfectly" Read more

240 customers mention111 positive129 negative

Customers are mixed about the battery life of the gas smoke fire alarm. Some mention that it comes with a 9-volt battery included and a backup battery. However, others say that it's difficult to replace the battery and it died in 8 months.

"...It's super hard to take the battery out unless you un-attach the smoke detector from the ceiling/wall. Even then it is pretty hard to take out...." Read more

"...They even came with 9 volt batteries. The batteries last a long time in these units since they are simply backups. The detectors are AC powered." Read more

"...Lifetime has been a little shorter than I would have expected. But, the replacement process has been quick and easy." Read more

"...Ties in to other monitors which is awesome and has battery backup!!" Read more

181 customers mention42 positive139 negative

Customers are dissatisfied with the noise produced by the gas smoke fire alarm. They mention that the beeping is just loud enough that they can't sleep through it. Some say that the alarm starts chirping late at night, just as the family was going to sleep. They also say that it makes a full alarm sound rather than making the little chirps. Some customers also say the alarms start triple-chirping which indicates that the unit needs to be replaced.

"...Make sure to have ear protection or something as the alarm going off can be really loud especially if you are just right next to it...." Read more

"...I couldn't trace the source by myself and the chirp made sleeping in the bedroom impossible...." Read more

"...I’ve had to replace the batteries on 3 of the units and one of them just continues to beep. 1 out of 6 isn’t bad - but 1 out of 6 isn’t great either...." Read more

"...Beeping instantly stopped. Since the detector is up high, I couldn’t have stopped it manually. So glad it stopped by itself. Very good product." Read more

Great choice
5 Stars
Great choice
Install was super easy. Tested fine. And looks nice. I took the picture in low light to show the green light. Reliable brand. I'll be buying another one too replace my other old smoke detector.
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Top reviews from the United States

Reviewed in the United States on March 4, 2024
Size: 1-PackPattern Name: DetectorVerified Purchase
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5.0 out of 5 stars Great choice
Reviewed in the United States on March 4, 2024
Install was super easy. Tested fine. And looks nice. I took the picture in low light to show the green light. Reliable brand. I'll be buying another one too replace my other old smoke detector.
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Reviewed in the United States on March 24, 2024
Size: 3-PackPattern Name: DetectorVerified Purchase
Reviewed in the United States on March 16, 2024
Size: 3-PackPattern Name: DetectorVerified Purchase
Reviewed in the United States on February 16, 2024
Size: 3-PackPattern Name: DetectorVerified Purchase
Reviewed in the United States on May 18, 2020
Size: 3-PackPattern Name: DetectorVerified Purchase
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4.0 out of 5 stars Dual Function Is Nice But Battery Removal Not So Much
Reviewed in the United States on May 18, 2020
I got the 3 pack of these smoke/carbon monoxide detectors for my house as the old ones are starting to malfunction. My house is from 1998 and the old detectors haven't been changed since then besides the battery. They are starting to have problems and start randomly beep throughout the night even with the battery out or with fresh batteries. I'm glad that I found these as these have the dual smoke and carbon monoxide detector. I'm glad these are dual function as California requires carbon monoxide detectors in the house. My old ones were only smoke detectors.

Installation:
These smoke detectors were easy to install for me. Each detector came with its own hardwire to use. However, since my old detectors were already hardwired, I just needed to plug it in for it to work. One thing that I had to do though was unscrew the old plate from the old detector and install the new plate. This actually took the longest as unscrewing took a little bit because of the long screws. Something to note: These detectors do not come with screws for the plate so if you need screws go to Home Depot first or somewhere similar. These detectors also come with instructions so they should be pretty easy to follow if needed.

One of the cons of these detectors is that the battery seems to be jammed in pretty good. It's super hard to take the battery out unless you un-attach the smoke detector from the ceiling/wall. Even then it is pretty hard to take out. I'm not looking forward to the day that I have to change the battery in the middle of the night for these. Hopefully that won't be for a while. One of the other things I noticed when installing these alarms was that one randomly went off after I installed one of them. Another one started beeping with the low battery sound right away and went away after 5 minutes. I don't know if it's because of bad design or defective product but they seem fine now and have the green light. Just something I thought I should mention for those looking to buy this product.

Usage/Function/Testing:
After installing these, you can test the alarm by using the "test" button on the detector. Make sure to have ear protection or something as the alarm going off can be really loud especially if you are just right next to it. It was loud enough for me to hear throughout the house. Make sure the alarm also has a steady green light as this means that it is functioning correctly. Overall, easy to use and we'll see how long this lasts before it needs to be changed.

I recommend this product to anyone who needs a replacement of their carbon/smoke detector. This took only a few minutes to install and was relatively easy. Only a few cons as I mentioned above which is why I gave this 4 stars instead of 5.
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16 people found this helpful
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Reviewed in the United States on March 14, 2024
Size: 1-PackPattern Name: DetectorVerified Purchase
Reviewed in the United States on January 28, 2024
Size: 6-PackPattern Name: DetectorVerified Purchase
One person found this helpful
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Reviewed in the United States on March 11, 2024
Size: 6-PackPattern Name: DetectorVerified Purchase

Top reviews from other countries

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jill
5.0 out of 5 stars works very well
Reviewed in Canada on September 14, 2023
Size: 1-PackPattern Name: DetectorVerified Purchase
Michèle
5.0 out of 5 stars Carbon monoxide and fire alarm
Reviewed in Canada on September 3, 2023
Size: 1-PackPattern Name: DetectorVerified Purchase
Clyde Cohen
5.0 out of 5 stars replacement product
Reviewed in Canada on August 8, 2023
Size: 1-PackPattern Name: DetectorVerified Purchase
bilodeau suzanne
5.0 out of 5 stars Facile d’installation
Reviewed in Canada on December 15, 2023
Size: 1-PackPattern Name: DetectorVerified Purchase
Spud
4.0 out of 5 stars Best for the buck?
Reviewed in Canada on October 7, 2022
Size: 1-PackPattern Name: DetectorVerified Purchase