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The First Alert 120VAC Hardwired Smoke Alarm with Battery Backup work exceptionally well in detecting flaming fires. Capable of wiring directly into your home's electrical system, these alarms feature a near effortless installation process. This alarm comes equipped with a Mute Button that serves the dual purpose of quickly silencing your alarm as well as testing its function. First Alert's series of 120VAC Hardwired Smoke Alarms with Battery Backups also come equipped with an EZ access battery door that removes the hassle and burden of collecting your alarm from the ceiling and replacing its batteries. The combination of a Battery Backup that provides optimal protection in the event of a power outage and an increased emphasis on the unit's 85d output establish the ultimate in peace of mind. This alarm comes with a 10 year limited warranty and complies with UL217 Standards. Save additionally with the purchase of this bundle.
Ionization Sensor Reliably Detects Flaming Fires
The First Alert 9120B Hardwired Smoke Alarm with Battery Backup comes equipped with an ultra-reliable ionization sensor to provide the earliest possible warning of a fast-flaming fire. The sensor is optimized to detect flaming fires, such as those caused by paper, kitchen grease, and other fast-combusting materials.
Gasket-less for Easy Installation
To facilitate hassle-free installation, this smoke alarm features a streamlined mounting system with a gasket-less base. The mounting bracket keeps the alarm secure over a wide rotation range while maintaining perfect alignment. The alarm also comes with a dust cover to keep the unit clean during construction. AC-powered smoke alarms must be installed in accordance with all local electrical codes.
Battery Backup for Detection During a Power Outage
This smoke alarm is designed for hardwired installation, but it also features a battery backup that helps ensure continued functionality in the event of a power outage. The unit comes with a 9-volt battery and features a pivoting, easy-to-access battery drawer that allows you to replace the battery without dismounting the alarm.
Works in Tandem with Other First Alert Alarms
In addition to functioning independently, this smoke alarm can also integrate with up to 12 other First Alert or BRK hardwired alarms for coverage of larger spaces. It also integrates with up to six other compatible devices, such as bells, horns, and repeaters. If one alarm in the series is triggered, they will all sound. The alarm features a latching indicator to identify which unit triggered the alarm, alerting you to the area of danger.
First Alert Smoke Alarm 9120B-48P
Recommended replacement for the following obsolete models:
First Alert SA4120B
First Alert SA4121B
First Alert SA4919B
Average Rating Based on 3 reviews: (5)
I was glad to find online. - 05/26/2015
Reviewer: Ken Spurling
I needed a lot of smoke detectors and could never find enough at the local Home Depot or Lowes.
Reviewer: Patrick Dempsey
They were to replace old smoke alarms and it was easy and simple all unit owners were well satisfied.
5 - 07/28/2014
Reviewer: Ray Young
Other reasons include: It could be a different device or appliance such as a security system, monitor, carbon monoxide alarm, or other device which has a similar low battery or alert signal. Some of the same factors that cause unwanted alarms can cause intermittent alarms: dust and insects in the alarm or power interruptions in hardwired alarms. Improper wiring on AC or AC/DC smoke alarms. AC alarms will chirp every 5 seconds if the interconnect wire is grounded. The orange interconnect wire should NEVER be grounded; it should only be used to interconnect other smoke alarms or compatible devices.
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