FIRST ALERTBRK SC9120LBL Hardwired Smoke and Carbon Monoxide (CO) Detector with 10 Year Sealed Battery Backup , White

I was looking for a replacement smoke/CO detector since my old detector had to be replaced after 8 years (which I thought should be 10 years). The old detector started chirping because of low battery. However when I replaced the battery, it was still chirping, but this time it was 5 beeps every minute. Looking at the back of the detector I saw the manufacturing date of 2014 but I also noticed the warning that 5 beeps means it needs to be replaced.The old detector is a First Alert combo with a 9v battery backup. The battery itself needs to be replaced every 6 months, which is really a hassle as well as it costs $8 for a pack of 2. Thus I wanted to find a new combo detector with a 10-year lithium battery. This is probably the best option since the battery lasts as long as the detector itself. The whole unit can be replaced every 10 years. This also saves a lot on the battery replacement itself. Plus the unit is just $10 more than the one with the 6-month battery backup.Installation was very easy since this unit has the same size as the old one, so I just use the old bracket since it fits perfectly. Also the old wire connector plugged in perfectly into the slot in the new unit. This is why I chose the same brand, to ensure perfect replacement fit. The only thing I had trouble with was the tab, which needs to be pulled out to activate the battery. It was very hard to pull it out, so I had to open the battery compartment (which was pin-locked) and pull out the tab completely.So my advise is, if you plan to replace your combo detector, just choose the same brand to ensure compatibility and easy installation. I would recommend this unit since it has a 10-year battery backup for peace of mind. Hopefully this will last 10 years as promised. That's a battery saving of $40 right there for a new unit like this in another 10 years. I also plan to get another 3 units of this model to replace when I hear another low battery beeps of the old ones.

These things might work too good. Any small bit of smoke in the house and these bad boys pick it right up. I installed these in my house I just finished building. They work great. Easy to install also.

This replaced the same model after 9.5 years of reliable service - 8 units total. So glad we upgraded to the sealed lithium battery model. No problem removing the plastic tab from the battery compartment. Just pull tab straight out with strong, even pressure. Plugged them in to the existing electric harnesses, rotated them into the existing mounting bracket, turned on the power at the circuit breaker and tested each one. Success! No more trying to change a battery in the middle of the night every few months…. P.S. It’s LOUD!

I have 7 hardwired smoke/carbon dioxide detectors. Like most people I have been awakened in the middle of the night when the battery runs low and the system starts chirping. I am also an old man who has 12 ft ceilings. Replacing those batteries in the middle of the night requires me finding my 8 ft step ladder in a packed garage and perching myself 6 feet off the ground. I was relieved to see they now make 10 year battery sources that coincide with the lifetime of the alarm.I wanted to make sure that the new alarms fit the installed bases and wiring of my old alarms so I asked my low voltage installer and the staff at First Alert and they told me they would. (see photos for comparison of the old and new alarms). I ordered them from Amazon and installed them the same day. It was a perfect fit.If you do decide to make this change keep in mind that the battery compartment on the 10 year battery life alarms do NOT open even though they look like battery compartments on the old alarms that hold 9V batteries. Secondly, to activate the alarms pull the plastic tag out exactly in the suggested direction r it will be impossible to remove.I gave this a 4 star rating because the 10 year battery life is uncertain at this point. The installation was easy. The alarm itself seems more well lit on the ceiling. I am hoping to realize the benefit of keeping old men off of ladders in the middle of the night. A closing thought that I have is about the necessity of batteries in a hard wired alarm in the first place. Hard to believe there is not a better way to alert the homeowner that the power to the smoke and CO detectors is down.