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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
Average Rating Based on 43 reviews:
Smoke Alarms - 09/25/2018
Reviewer: Christopher Cooney
Very easy & clean installation. Installs within minutes. The side battery installation is easy & very convenient. Item works great with no chirping or false alarms.
Reviewer: Dennis Atkinson
replaced my worn out alarms great quality great price
smoke alarms - 02/14/2018
Reviewer: charles mcdonald
Easy Install - 01/23/2018
Reviewer: adam myers
So far so good. Easy to install. Tested that they were all linked and everything is working well. Knock on wood.
Reviewer: Ronald Darrell
Awesome - 10/31/2017
Reviewer: Michael Gordinier
Product as described super fast shipping. Replace old First Alert sensors - new connectors were very easy to install. Would buy again.
Excellent service - 10/16/2017
Reviewer: P Kornowske
Product delivered on time and was exactly as described on the site. I purchased these to replace previously installed detectors that had reached their life span. Included instructions easy to follow.
Owner of resident - 10/04/2017
Reviewer: Alan Collier
VERY GOOD PRODUCT AND EASY INSTALLATION. WORKING GREAT AND FEEL SAFE. THX
Reviewer: Kenneth Miller
I started a new propane stove after installing these smoke detectors and the stove initially was very smoky and the detectors worked well
Reviewer: Bobby Marcus
Previous detector retired. Easily installed new back plate and installed new detectors.
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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