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BRK 9120B Smoke Alarm, Dual Ionization, 120V Hardwired w/ Battery Backup
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The BRK 9120B smoke alarm is a great choice when it comes to affordability. Redeigned from the ground up, BRK created the 9120B model to directly replace past BRK smoke alarms while greatly improving sensing technology, installation ability, and improved connectivety. The first alert 9120B smoke alarm has an 85dB horn, 9V battery back-up and a silence feature.
The BRK 9120B smoke alarm uses dual ionization technology to reduce false alarms more efficiently and more accurately than ever before. The 9120B smoke alarm is designed for sleeping rooms in your home, hospitals, hotels, motels, college dormatories and multi-family housing units. This BRK smoke alarm complies with NFPA101, UL217, CSFM, NFPA72, HUD, FHA, and other agencies. Where AC/DC silent smoke alarms are required, BRK smoke alarms work perfectly.
The BRK 9120B model has the ability to be interconnected within a circuit of alarms and other alert devices such as bells, whistles, repeaters, fans, or switches. You can connect up to 17 BRK devices of which 11 can be smoke alarms, and 6 can be alternate devices! Integrated within the BRK 9120B smoke alarm is a 9V battery backup to make sure your smoke alarm does not loose operation when power fails which providing added security and peace of mind.
All around, BRK smoke alarms are the perfect choice if you are looking for affordability, function, and ease of use.
BRK Smoke Alarm Replacement
This BRK Electronics 9120B smoke alarm is the direct replacement for the discontinued BRK smoke alarm models 4120B, 4120SB, 4919 and 86RAC. Wiring harness and communication protocol is the same across BRK models (i.e. a 4120B will talk to a 9120B). When replacing an older smoke detector, only the mounting bracket needs to be changed.
About BRK Smoke Alarms
For over 50 BRK smoke alarms have been the preferred smoke alarm to protect lives. BRK makes hardwired, battery operated, and plug-in smoke alarms for professionals, remodeling, homeowners. Designed for easy installation, easy mainatenance. Many BRK smoke alarm models can be interconnected with their patented OneLink® and has quickly become the preference for contractors. Many of BRK smoke alarms
- 120 VAC; Interconnectable
- 9V Battery Included
- AC Power Indicator
- Alarm Indication
- Battery Activation Tab
- Battery Back-Up
- Battery Drawer Lock
- Easy Install Mounting Bracket
- Ionization Sensor
- Low Battery Warning "Chirp"
- Missing Battery Tab
- Mounting Bracket Lock
- Quick Plug-In Power Connector
- Swing-Open Battery Door
- 120V AC
- Alarm Dimensions: 5.6" dia x 2.0" H
- Audio Alarm: 85dB at 10 feet
- Humidity Range: 10 percent to 90 percent relative humidity (RH)
- Operating Current: .04 amps (standby/alarm)
- Operating Voltage: 120V AC 60Hz w/ 9V battery backup
- Temperature Range: 40 Degree F (4 Degree C) to 100 Degree F (38 Degree C)
- Weight: 7.8 oz (9120B)
- 10-year warranty through BRK Electronics
- Customer Reviews
Good quality product
One of the go to hardwired smoke alarms!
on 01-29-2016 by MMC
I ordered 970 smoke detectors (BRK9120B) all were in good working condition none of these had to be sent back or replaced even the batteries are holding up which was very surprising to me because usually I get low quality batteries that have been in a warehouse for 10 years when I buy an item with batteries already installed. I was 100% satisfied with this purchase.
on 11-16-2015 by Ronald
Easy replacement and reasonable
My original BRK smoke alarms started acting up after about 10 years. Only then did I find out that smoke alarms have a lifespan of about 10 years and should be replaced. These were perfect replacements for what I had, and have worked perfectly (no chirping) since I installed them.
on 11-02-2015 by Joe
Almost 1/2 Price!
These were the same electrical connector as my1996 models which I replaced 7 of. What a great price!! $15 at Home Depot each, $8 here...no brainer. Even bought a spare and shipping was still less than Home Depot by $32! Smoke alarms shipped in three days!
on 03-08-2015 by DirtyHarry
Easy to install can be interconnected with others smoke detectors in bedrooms and hallways and on each level of your house. Wired 120 volt and battery backup makes these very dependable to protect your family.
on 10-24-2014 by Doug
i think it is really good
it is excellent, it can detected smoke fast, it really help to maintain protected from fire.
on 09-18-2011 by eli
Easy to Install but . . .
Great service and price from Westside. Got these to replace outdated contractor-installed alarms. These installed easily on existing mounting rings and electric pigtails connected right to existing connectors. But these alarms are susceptible to spiders getting inside and setting off false alarms, usually in the middle of the night. While the case protecting the ionization detector has slots to prevent bugs from having direct access, small spiders get in through the gap between the mounting ring and the alarm case and set off the alarms. With the alarms being interconnected, the middle of the night the spider-induced alarms' sounding is, well, alarming. Then it''s usually necessary to take down the alarm with the problem and shake it vigorously to get the spider out.
on 07-29-2011 by Kawasaki Biker
Difficult to replace battery
These were installed in a newly built house that we bought in 2007. The only problem I have is that inserting the battery is very difficult. Otherwise I would give it 5 stars for quality.
on 02-16-2011 by Florida gal
Replaced 3 BRK 86RAC smoke alarms with 3 new BRK 120V Hardwired 9120B models. They ARE a direct replacement for the old ones, same plug ins. Out of the box, put up new brackets, old screws aligned perfect, plugged in, and pulled the battery tag. Did all three in less than ten minutes. Also received on delivery date, could not have been more simple. Outstanding!!!!
on 12-31-2010 by RFH
mon a mi
bonjour. what is for us is different than the states. we find these and buy for to change our old one. thank you for this. Ciao
on 02-17-2010 by Georges
this is right
part of the problem was that no one knew that this would work. after we called westside they shipped these to us and we installed them. so far, no issues. I guess as far as smoke detectors go, their sort of cute. much better than the old yellow ones that we had up there. I'm not even sure if they make them anymore.
on 02-17-2010 by Jennifer
we have the old ones and now we have the new ones and this is what we need. PJ installed them in all the rooms and then came back to tell me and I was surprised. He installed them so quickly. I was on this website looking for the shower heads and i see that this is what looks like I have. I think that maybe this is the best one on the market because i don't like cheap things.
on 02-17-2010 by Mr. Patel
I wish that I had known these were here. This is exactly what I needed. The connector is the same and thats important
on 02-17-2010 by Sussie LImpkin
I recently purchased 8 of these units for my home. They installed in minutes and work great!
on 02-03-2010 by Howie
direct plug in replacment
Had to repalce all the smoke alarms in my 15 year old house. These are direct replacment for the older RK alarms. Just had to change out the plastice mounting rings and they plugged directly into the original plug, no wiring changes. The units will tell y9ou which alarm is causing the alarm. The older ones took troubleshooting to find the offending unit.
on 05-10-2009 by PeteExcellent rplacement better technology
Talk about easy installation!
I recently had to replace my old 4120B. It took me 15 minutes to get it wired up and in the ceiling. At this price I might as well replace them all since its so simple.
on 02-19-2009 by Ethan
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- Questions & Answers
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Why does my smoke alarm beep every 30 seconds? How do I get it to stop?by Joan T. on 04-06-2015
The beeping may be due to needing to change the batteries or it could mean that it is time for new smoke alarms. The lifespan on a smoke alarm is about 5-7 years.on 04-07-2015
What is the difference between the BRK 9120B and the BRK SC9120B?by Robert F. on 03-01-2015
BRK 9120B is only a smoke alarm, while the BRK SC9120B is a smoke and carbon detector.on 03-03-2015
I need a replacement for the BRK 1839WN. Will the BRK 9120B work for me?by Linda B. from MO on 02-16-2015
The BRK 1893WN has been discontinued, the best replacement would be the BRK 9120B. Since the alarm you have now is an older series there would be some rewiring involved.on 02-17-2015
I am interested in some new smoke alarms and would like to know if I was to buy the 120V alarm, could I use them on 9V without hooking them all up on AC?by Charles H. on 01-08-2015
No, per the manufacturer that is not recommended and can actually pose a fire hazard.on 01-14-2015
What is the difference between the BRK 9120 and the 9120B smoke detectors?by Allan J. on 06-16-2014
The BRK 9120 is hardwired only, while the BRK 9120B is hardwired with a battery back up.on 06-17-2014
I have the BRK SC9120B. Will the BRK 9120B be an exact replacement? The remaining units in my house all still tested ok.by Floyd S. on 06-10-2014
You are able to replace a BRK SC9120B with a BRK 9120B, but please keep in mind that the BRK SC9120B is a smoke and carbon monoxide detector while the BRK 9120B is just a smoke detector.on 06-10-2014
I am replacing the BRK 86RAC units (have 5 of them) because one occasionally just begins to sound for no obvious reason. Is there a direct replacement or will the BRK 9120B smoke alarm use the same plug-in connector?by John S. from NJ on 02-01-2014
The BRK 9120B is the direct replacement for the BRK 86RAC.Wiring harness and communication protocol is the same across all models. When replacing an older detector, only the mounting bracket needs to be changed.on 03-17-2014
I have an older model BRK 4120B smoke detector that is chirping. I purchased this house from the original owners but cannot find a replacement. Please help.by Dennis F. on 01-11-2014
The BRK 9120B smoke alarm is the direct replacement for the BRK 4120B.Note: This item is the DIRECT replacement for the discontinued BRK 4120B, 4120SB, 4919 and 86RAC. Wiring harness and communication protocol is the same across all models (i.e. a 4120B will talk to a 9120B). When replacing an older detector, only the mounting bracket needs to be changed.on 03-26-2014
When should one replace a fire alarm unit. I have the old model 4120B for about 7 yearsby Howard C. on 10-10-2012
It is recommended that you replace your smoke alarms every 5-7 years, unless otherwise specified. The BRK 9120b has an extended warranty of 10 years.on 10-16-2012
can you still buy the brk 4120b smoke detectorsby chuck T. on 07-23-2012
No, the BRK 4120B smoke alarms have been discontinued by the manufacturer, and they have released the 9120B as an direct replacement.on 07-23-2012Please login or register before adding a question.