FireX Hardwire Interconnectable 120-Volt Smoke Alarm with Battery Backup-21006371 - The Home Depot


Model # 21006371

Internet # 100573489

Store SKU # 146389

Hardwire Interconnectable 120-Volt Smoke Alarm with Battery Backup

FireX Hardwire Interconnectable 120-Volt Smoke Alarm with Battery Backup

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

$19.97 / each


Model # 21006371

Internet # 100573489

Store SKU # 146389

The Kidde Hardwire Interconnect able Photoelectric Smoke Alarm with Battery Backup can act as a stand-alone unit or can be integrated into an existing electrical system. This unit sounds an early warning to alert you and your family of the presence of visible fire particles detected by the alarm's photoelectric sensor. Powered by 120-Volt AC, this alarm protects you, your home and the people you hold dear even during power outages, thanks to a 9-Volt battery backup. A power harness facilitates an easy installation and a simple push of a button activates this alarm's test and hush features.

  • Utilizes photoelectric sensor to detect visible fire particles
  • Sounds an early warning when smoke or fire particles are detected
  • Offers dual functionality as a single-station alarm or can be interconnected into a wired system
  • 120-Volt AC, 2-wire connection
  • Push-button operation tests alarm functionality
  • 9-Volt battery backup provides protection during power outages
  • 9-Volt battery included
  • Pull tab keeps battery fresh until initial activation
  • Power harness makes installation fast and easy
  • Dust cover protects sensor during construction

Info & Guides

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Product Depth (in.)  1.55  Product Height (in.)  5.6 
Product Width (in.)  5.6 
Alarm Sensor Type  Photoelectric  Alarm Type  Smoke 
Alarm/Detector Features  Battery Back-Up,Hush Feature,Interconnected  Commercial / Residential  Commercial / Residential 
Connector/Contact Type  2-Wire  Included  Batteries 
Power Source  Hardwired  Returnable  90-Day 
Voltage (volts)  120 
Warranty / Certifications
Certifications and Listings  1-UL Listed 


Rated 3.9 out of 5 by 25 reviewers.
Rated 1.0 out of 5.0 by Short life before repeated false alarms. I have 12 Kidde detectors, four models. I've owned others over 20 years. I had...had..four of this model. All four began giving false alarms, one then the next, between 12-18 mos after install. The irony is that these four were chosen over dual sensor units, not to save money, but because having photoelectric only units near the kitchen and bathrooms is recommended to avoid false alarms in humid environment with "PI" or "I" units. I have had no problems with Kidde dual PI2010's or the four combo photoelectric/co2's that I have. Choose another model. I just threw four of these in the trash. July 1, 2014
Rated 5.0 out of 5.0 by always great service and great products and prices easy to install,also home depot had great assortment of electrical connectors April 8, 2015
Rated 5.0 out of 5.0 by Smoke Detector The smoke detector was easy to install. I also liked the feature that even if the batteries are dead, that the 110 current will keep it working for safety. March 12, 2015
Rated 2.0 out of 5.0 by Inconvenient Battery Access I bought 6 of these to replace horrid BRK 4120B models that go off for no reason. Unfortunately, this model has doesn't have side access to the battery. You have to unscrew the alarm, and then ALSO unhook the hard-wire connection before opening the battery case. Yeah, they're easy to install the first time, but if you plan on changing the batteries (which of course you must!) good luck! Guess these are more marketed to contractors, not homeowners who will actually maintain them. March 16, 2013
Rated 4.0 out of 5.0 by Great replacement for our older Ionization unit that was always going off in the kitchen We used this unit as it was made by the same people as the existing unit and the form factor and the mounting were the same. This meant that we did not need to repaint the ceiling or even touch it up. The unit has not created any false alarms so far and we have had it in place for about 2 months. It is located just outside the kitchen where the old ionization unit was and that unit was always going off whenever we made anything that gave off even a little smoke. January 27, 2015
Rated 3.0 out of 5.0 by Kidde FireX Smoke Alarm After the tornado & repairs to our home, our contractor installed 2 of these Photoelectric Smoke alarms in two bedrooms (one room has no door used as an office) and 3 Combination Smoke/CO2 alarms one in our hallway near the kitchen, one upstairs in finished attic and one in the cellar in 2012 after final inspection from the building inspector. Small 4 room cape style house. Can't bake in the oven over 425° or deep fry on the stove, the alarms go off. The alarms have gone off 2:20 am and 3:00 am for no reason. They're interconnected, so they beep and yell out FIRE FIRE FIRE.. My pets are frightened as we are too. I called Kidde and the person asked if we had ceiling fans, of course we do, the one in the bedroom is going all night and every night. She said they throw dust and that could be why they go off. I have to climb a ladder to clean them with the dust remover or vacuum. The contractor said the model p12040 which is in the bedrooms may be the ones setting off the others. Kidde representative said the batteries I have may have caused trouble . I bought Duracell MN1504 9V as specified in their manual. exp. DEC 2018. She tried to say this battery with the expiration date may have problems. I called Duracell to report this and they said there has been no complaints. But when I sent an email to that woman from Kidde about contacting Duracell, she called me saying she didn't say that. She originally asked me to buy Energizer # 522. They did send me free replacement Smoke alarms as they have a 10 yr warranty. But I'm afraid to install them. Any suggestions? We can not install another brand as we have the Combos that are wired to the electric. Also the manual says there's a HUSH button! Wrong.. The TEST button is supposed to be the hush button, but that didn't shut it off. February 7, 2015
Rated 1.0 out of 5.0 by This is not a good product! I purchased 11 detectors and have them wired with the interconnect feature for a newly built house based on the good reviews. Appr. 3 months - 6 months afterwards these detectors would go off randomly at all hours of the day and night. There is nothing in the instructions that provide any guidance on what may be the cause. I tried to call there customer support line for help and after being on hold for longer then I liked I sent an E-Mail which was never replied too. I decided to change ALL the batteries with brand new well named batteries and it only took 6 weeks for the 1st one to go off (the only good feature with these units is being able to determine which detector is sounding the alarm). As of these writing 3 have been removed. The only option that I see to resolve this issue to to start to shop around for something other then Kiddie detectors. October 10, 2013
Rated 5.0 out of 5.0 by Purchased PE120 Photoelectric Smoke Alarms I replaced 13 year old units with the same PE120 from Home Depot. Used the online HD site to research and picked up in store. Purchased 8 units receiving bulk discount. Installed all 8 within a 1.5 hrs. Home was already wired so it was straight forward to replace the base and plug in the new unit. So far so good. They tested fine and after 20 hours no chirping. I believe it’s important to replace all unit at once to maintain the system wide connection. HD had the best pricing on these units. January 26, 2013
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