FireX Hardwired Interconnected 120-Volt Smoke Alarm with Battery Backup-21007581 at The Home Depot
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Model # 21007581

Internet # 202029419

Store SKU # 343598

Hardwired Interconnected 120-Volt Smoke Alarm with Battery Backup

FireX Hardwired Interconnected 120-Volt Smoke Alarm with Battery Backup

This item has been discontinued.
The Home Depot no longer carries this specific product.

$14.97 / each
Item cannot be shipped to the following state(s): GU,PR,VI


Model # 21007581

Internet # 202029419

Store SKU # 343598

Store SO SKU # 198092

FireX i4618 alarm is a 120V hardwire smoke alarm and battery back-up feature. Utilizes ionization technology that may detect fast flaming fires sooner than photoelectric. Install this alarm in your home to provide you and your family an early warning in the event of a fire. Battery back-up feature provides protection even during power outages and the smart hush feature will silence false alarms.

  • Front loading battery feature for easy battery change, no need to remove the alarm from the ceiling
  • Test/reset button allows you to check on the sensor's functionality and cease false alarms
  • 9 Volt battery backup provides protection during power outages
  • Pre-stripped wiring harness with easy off cap provides easy access to wiring components
  • Interconnectable feature with up to 24 devices of which 18 can be initiating
  • Unit is equipped with piezoelectric horn that is rated at 85 decibels at 10 ft.

Info & Guides

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Alarm Sensor Type  Ionization  Alarm Type  Smoke 
Alarm/Detector Features  Battery Back-Up,Hush Feature,Interconnected  Assembled Depth (in.)  3 in 
Assembled Height (in.)  6.25 in  Assembled Width (in.)  6.63 in 
Certifications and Listings  1-UL Listed  Commercial / Residential  Commercial / Residential 
Connector/Contact Type  2-Wire  Included  Batteries 
Returnable  90-Day  Voltage (volts)  120 


Rated 4.1 out of 5 by 82 reviewers.
Rated 5 out of 5 by Great basic smoke alarm. This is a great basic smoke alarm at the right price. Easy installation and looks good. I have had no nuisance alarms. This alarm is interconnected to all the alarms in my house. If one alarm is activated, they all alarm. November 18, 2013
Rated 5 out of 5 by Smoke Detector the smoke detector works fine, the associate at Home Depot was very helpful. September 25, 2014
Rated 1 out of 5 by Problem with High Humidity I installed six 4618's in my home here in Hawaii. Was easy to do & went in fine ... I thought. Whenever it rains and is cool (i.e. high humidity conditions), they go into nuisance alarm. And because they are all interconnected, they ALL go off (not their fault, lousy code). But the unit that went into "nuisance alarm" is NOT indicated by LED, exacerbating the problem. I suppose I will pursue the photo-electric variety instead. But buyer beware of use of a 4618 in a humid environment! May 29, 2013
Rated 1 out of 5 by Continuous false alarms There is a reason for a "Quick Hush Feature for False Alarms" on these units. I would not recommend this smoke alarm to anyone that likes their sleep. It constantly went off with false alarms. And with them being hard wired together, the whole house rang out when one would go off. After following the directions from the company and from posts of people who complained, I still kept getting them. Although they may be fairly priced, they are not worth the headache. November 13, 2013
Rated 4 out of 5 by Many good features Replaced aging ones with these. They installed very easily and the battery back-up is a great safety feature. LED indicators give you a status update at a glance. June 11, 2014
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