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Designed to help promote household safety, the First Alert 9120B Hardwired Smoke Alarm with Battery Backup can provide a vital early warning of fire. This hardwired smoke detector uses an ionization smoke sensor to reliably detect smoke from hot, fast-flaming fires.
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 9120B6CP
Recommended replacement for the following obsolete models:
First Alert SA4120B
First Alert SA4121B
First Alert SA4919B
In this guide, we'll be showing you how to install First Alert Hardwired Smoke and Carbon Monoxide Alarms. Here are a few items you'll need before starting the installation process: Needle-nose pliers or utility knife, screwdriver, wire stripper, wire nuts and a ladder.
Hardwired Smoke or Carbon Monoxide Alarm Requirements:
To begin, turn off power at the junction box and connect your alarm to the building's electrical wiring.
|Attach to black wire on power connector|
|Attach to white wire on power connector|
Standalone (single-station) alarm: This wire is not needed; tuck the orange wire into the junction box.
If you are installing more smoke or carbon monoxide alarms, you'll want to repeat the process throughout the building. Interconnected smoke and co alarms must meet all requirements:
The same fuse or circuit breaker must power all interconnected alarms.
Up to 18 compatible detectors can interconnect, with a limit of 12 smoke alarms.
The total length of wire interconnecting the alarms should be less than 1,000 ft. (300 meters). This type of wire is commonly available at hardware and electrical supply stores.
All wiring must conform to all local electrical codes and NFPA 70 (NEC). Refer to NFPA 72, NFPA 101, and your local building code for more information.
Interconnect wiring diagram:
If you have any doubts or reservations about these interconnect requirements, please contact an experienced electrician to install your wiring and hardwired alarms.
Once you've installed your hardwired alarms, you'll want to restore power to the junction box. Under regular operation, the power indicator light on the alarm will shine/blink to indicate that it is receiving AC power.
Here's how you can test standalone or interconnected alarms:
Standalone Alarms: Press and hold the Test/Silence button until the unit triggers an alarm.
Interconnected Alarms: Press and hold the Test/Silence button until the first unit triggers an alarm. All interconnected detectors should sound off. Repeat this process to test each alarm in the interconnected series.
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