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The First Alert 120VAC Hardwired Smoke Alarm with Battery Backup works exceptionally well in detecting flaming fires. Capable of wiring directly into your home's electrical system, this smoke detector features a near effortless installation process. This hardwired smoke alarm comes equipped with a Mute Button that serves the dual purpose of quickly silencing your detector as well as testing its function. 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 85db output establish the ultimate in peace of mind. This First Alert Hardwired Smoke Alarm comes with a 10 year limited warranty and complied with UL217 Standards. Save additionally with the option to bundle.
Ionization Sensor Reliably Detects Flaming Fires
The First Alert 120VAC 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.
Test and Silence Button
Mute Button has been included to serve the dual purpose of silencing nuisance alarms and testing the functionality of your alarm.
EZ-Access Battery Door
The addition of an EZ Access Battery Door removes the hassles and burdens associated with changing your alarm's batteries.
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.
Recommended replacement for the following obsolete models:
First Alert SA4120B
First Alert SA4121B
First Alert SA4919B
First Alert 120VAC Hardwired Smoke Alarm with Battery Backup - SA9120BCN
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.
Average score based on 183 reviews
- Reviewed: 06/12/2018 by Mark Chlebecek
Replacements for original units / Fit well
- Reviewed: 03/19/2018 by Margaret M Wytrwal
Smoke Alarm w/Battery Backup
Exactly what I had hoped for. Great pricing and quick delivery
- Reviewed: 01/22/2018 by Theodore Taylor
Ease of Installation and Price
The 3 smoke alarms were much improved over the last ones I bought years ago with respect to being able to insert the alarm into the bracket with ease. Also all the alarms go off in any one of them detects smoke/fire. Would recommend them to anyone seriously interested in their own safety!
- Reviewed: 01/18/2018 by Dennis Reimink
happy in safety
I changed all of our 14 year old smoke alarms. It took less than 1 hour. We hadn't known the alarms are only good for a defined time.
- Reviewed: 01/17/2018 by Joe D
Thank goodness your local
Our smoke detectors decided to kick the bucket New Years weekend after 15 long years! We were so glad you were local - we were able to pick up the replacement devices and saved a TON of money versus buying replacement devices from local big box stores. Your staff was so friendly and so accommodating! I hope all of my neighbors buy their replacement devices direct from you when the time comes!
- Reviewed: 01/10/2018 by jackie floen
No problem with orders, received exactly what I ordered, prompt delivery.
- Reviewed: 01/10/2018 by Kathy Romano
Easily replaced our existing alarms that are no longer working with these.
- Reviewed: 12/26/2017 by JoAnn Landry
- Reviewed: 12/26/2017 by Ian Montgomery
Replaced a 8 year old unit, fit and worked as expected. Glad they still make this model. Would have been a pain to install another style.
- Reviewed: 09/04/2018 by John Meich
Replacement product is excellent and matches the current system!