First Alert BRK SC-9120B Hardwired Smoke and Carbon Monoxide (CO) Detector with Battery Backup

About 6 years ago I had this product installed in the basement, on the main floor and upstairs in our home. I had never had a problem until last month. The alarms were hardwired and contained a 9 volt battery in case the power was to go out. The alarms woke us up in the middle of the night and terrorized us for 24 hours. I changed the batteries on all of the alarms and they worked fine for a few hours then noise began again.Frightened that we may have carbon monoxide in the house, I called an electrician. Sixty-five dollars service call and $50 for one new BRK SC9120B Smoke and Carbon Monoxide Alarm later we were fine for about three hours, then the noise kicked in again.Unable to deal with the noise, I unplugged all of the alarms.I checked local stores for replacements for the other two alarms; however, one said they did not carry this brand and the other said that they would have to special order them. Finally, I checked amazon.com.Scheduled to go away for the weekend, I ordered two BRK SC9120B Smoke and Caron Monoxide Alarms using amazon.com and amazon.com's free "Prime" shipping at a total cost of $70.00. The following Monday morning the alarms arrived.With the old brackets in place, I followed the instructions, plugged the new devices in and screwed them into the brackets. The whole process took about 10 minutes and required about the same skill as screwing a light bulb in.They work fine now. After reading the instructions included with the box, I learned that these alarms are built to last 5 years. Mine lasted 6 years.I am comforted and sleep easy with the knowledge that my devices are top of the line smoke and carbon monoxide alarms with alkaline battery back-up that will protect me and my family for at least 5 more years.I saved a total of $30 on the devices I bought from amazon.com.Now that I know an electrician is not necessary to replace these alarms in the future, I will save the cost of a house call in addition to the list price of the alarms from the electrician.These are easy to install reliable devices that save lives. Enjoy!

We were quite confident in the safety of the system interaction since the new alarm types matched the existing alarms in our home. Tested it with the existing system, and no issues. The design was perfect for us and there is a clip that connects the alarm’s wiring to the home’s existing wiring that we removed and replaced with ease.

Easy to use. It was a direct replacement for my original units which are all failing after 10+ years.

This is the exact match for my system. Only issue is it says last 5 years, my whole house has these and they are 9 years and work perfectly. Hope this one does the same

10/2011 UpdateOne unit malfunctioned last night, 10/2011, which is why I am on the sight purchasing another unit and updating my review.As the units are in series it took some time to figure out which one was defective...I had to take two down, leaving the battery in until the bad one went off again to indicate it was malfunctioning. Why does it always happen at bedtime?I only give four stars on reliability for two reasons. First when I first received the four units, one was bad, so I had to return it for a replacement. Second the unit I am replacing is only 3 years old, when they are rated to last 5 years. If another unit goes early I will place them all with another brand if BRK does provide to sort of rebate.10/2008Originally had BRK alarms, but did research anyway as my alams were 15 years old. After doing my research decided on replacing all four of my existing alarms with this model, SC9120B. For just a few dollars more I figured it was worth having the CO2 detector on all levels of the house. Installation was simple, I replaced the connectors with the power on, NOT recommended, you need to be careful and not ground yourself, but it is much faster. The units went right in. HOWEVER one of the units was defective, it worked but did not trigger the other units to go off. After some switching of units I was able to determine which unit it was. Reqested a replacement, got it, installed it, and then returned the unit. Return was quick and easy.Some suggestions, tag the connectors in the electrical box, clearly identifing the installation date so you and others can tell when the units were installed. Before installing check the manufacture dates on the units themselves, do not accept older ones as the life of a unit is 5 years. While some people report receiving 1 to 2 year old units, mine were all only a few months old. Change the batteries once a year on a specific and rememberable date, such as the time change.The units work well, as I was leaf blowing outside this weekend and the units were triggered by the exhaust because the windows were open in the house. Turned on the whole house fan and the unit went silent after a few minutes.

We have a 2 year old home. One of our detectors decided to go haywire...in the middle of the night. We replaced it with this detector and allhas been quite and we have our peace of mind back.

I bought the same exact model, because the last one lasted me 11 years. Your should replace them every 10 years maximum.

This item works great and was an product type as I one that had to be replacedWould highly recommend this product