FIRST ALERT9120B Smoke Detector, Hardwired Alarm with Battery Backup, 6-Pack

Purchased a six pack for replacements of my 18 year old units, which by the way never gave us any problems. Replaced them all in December of 2017. Three months later (late February) as we were preparing to leave home for an appointment they all started going off and would not stop. Do you know how difficult it is to find which one is causing the false alarm? After running up and down the steps from the basement to the second floor, unplugging all of them (8 total, we also have two photoelectric sensors) I finally found the one causing the problem. I replaced the battery, only to have them go off again a few short minutes later. Ordered a new one and replaced the defect.Fast forward to July 1st, sleeping nicely at 6 am on a Sunday morning and here we go again, they all start chirping. This time it only lasted for about five minutes, enough time for me to run up and down the stairs looking for smoke or fire and the beeping stops. Of course, this wasn't enough time for me to find the defect. Now we get to go to sleep every night wondering when it's going to happen again. At least I have the confidence of knowing that when we're away we have another model hooked directly to our home alarm system, which will give us an alert over our cell phone. I just hope that a false alarm won't drive our parrot absolutely crazy if we're not at home.Time to look for another brand or model.

I hate these with a passion. They are super sensitive, so if I make a tiny amount of smoke on the stove, or in the oven, boom whole house is screaming about it. It is almost impossible to determine which unit has a low battery as they all seem to beep, not often enough (really). The fact that they are hard wired is both good and bad. This is great if there is an actual alarm, because they will all alarm. It is also bad if you ever plan to switch, or they discontinue the model who knows you may need to swap out every alarm. However, they are still 100X better than any smoke detector that want's an internet connection, so whatever... If you are replacing one, do it. If you have to replace a bunch, I would look into finding a better, less exhausting system.

I've had 9 of these in my home for over a year. While on the one hand, they seem to be doing their job, on the other hand, what IS their job? To sit quietly by and wait. And if they ever detect smoke, to warn you. Pretty simple.These detectors FAIL.FALSE ALARMS!!!!!!!!!I've never had a smoke detector in my 50 year life give false alarms...until now! These have some MAJOR design defect, because they go off for NO REASON, most often in the middle of the night.I'm not quick to judge either. I've wanted to believe that it's just an anomaly. It started only a few weeks after installation. Alarms going off at 3am or 4am. One night it was in one room, another night a different one. Random and unpredictable. I would reset the specific detector that alerted, then just hope it wouldn't happen again. Sometimes it wouldn't, for weeks. Sometimes it would, the next night. But I was patient, and asked my family to bear with them. Tonight I've simply had enough!!!! 3 times the one in my bedroom went off. 3 times I reset it. Then I disconnected it and set it aside. I've GOT to find another brand. I can't take it anymore with these.If you don't like sleeping peacefully, without your whole family being startled awake at 3am by false alarms, randomly for many nights in a row, with occasional weeks in between, then buy these. But be forewarned. They are the worst smoke detectors I've ever had, and will NEVER BUY FIRST ALERT AGAIN.What kind of product are they producing? One that fails to do its job. What's their advice if you call customer service? Vacuum all 9 detectors every week! REALLY???You gotta be kidding me!!! That's just a bad joke.Seriously, don't decide based on price or ease of installation. Decide based on whether or not you value your sanity.10/6/22 Here's an update...I have removed these detectors when they give a false alarm. I discovered that if I blast them with compressed air, then reinstall, they work normally, with no false alarm...for awhile. Can't say how long, but I've been doing it successfully for most of this year and haven't had any nighttime alarms. Take that for what it's worth...

Let me first say that I needed smoke detectors that didn't give me false alarms. I have a hardwired system of 7 alarms, and was considering the CO and smoke detector combo. NO! from all that I have read and reviewed, bad idea, both First Alert and Kidde can't seem to get it right, and have very often faulty alarms and premature deaths of the alarms. Photoelectric? Not as often, but from what I read and reviewed as well, same thing. I made my purchase on what I know as time tested and true! These alarms "BRK9120b" are the exact same thing that have been running in my home since 2007, and without one issue. In fact, all the old ones were working quiet well (incense test), before I replaced them. I didn't realize that they were way past expired until upon further inspection than the weekly test. The replacement of them for 6 took less than 30 minutes. The hardwired adapters were the exact same as the the ones installed in 2007. So what about the CO for my gas burning CO emitting stuff. Well I plan to get some standard stuff. I read a review of only one person that actually tested their CO detector before installing. How? He put it in front of his vehicle's tailpipe. Genius.I take smoke alarms pretty serious as one actually saved my life. Years ago I moved into an old home without one smoke detector. Installed several el cheapos in every room and called it a day. As the years went on and the batteries failed, I just yanked the batteries and planned on getting replacements. With a full time job, and night school, I just didn't get around to it. I had one smoke detector left that had a good battery. I fell asleep very exhausted (school finals), and awoke to a whole home full of smoke, my entire kitchen was ablaze. After rescuing my animals, I grabbed my garden hose and extinguished the fire. If that one smoke detector had a dying and chirping battery and I yanked it like the rest of them, I would not be writing this review today. Point being, I am a firm believer in keeping your smoke alarms up and running in peak performance. Set a yearly reminder in your cell phone to replace the batteries every 11 months (do it now!) Get up on a ladder and see how old your detectors are (there is a manufacturing date on the back). 9-10 years old, replace it. $50-60 bucks ain't worth you or your families life! Hope this message reaches at least one person. Also, as with all my reviews, should something fail, or go wrong, believe me, I update.

No returns on this products so buyers beware. I purchased 3 boxes and one was not used completely seal and I couldn’t return it.Product update. I guess you get want you pay for, half the smoke detectors don’t work right out of the box. There’s an issue with the battery tray that won’t close properly cause the green light to blink on and off. Awful that I only got 2 good smoke detectors out of 6 pet box and I purchased 3 boxes. Add insult to injury this product can’t be returned.I wish seller would contact me to figure something out.