Kidde i4618 Ionization Smoke Alarm, Hardwired with 9V Battery Backup (21007581)

Brand: Kidde
Model: i4618
Condition: New
Warranty: 5 Years
SKU: 126148
5 (2 Reviews)
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Kidde i4618

Regular Price: $11.99
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The Kidde i4618 Firex ionization smoke alarm (21007581) is a 120V AC/DC alarm with a 9V backup battery. Chock full of features, it's compatible for both single and multiple stations, with the 15-minute false alarm control element that will silence an alarm, if needed. This ionization smoke alarm also includes a front-sliding door for a 9V battery, test switch, dual-purpose LED indicator, and an 85-decibel horn.

A constant green on the LED indicator allows one to know if there is AC power available for use. A flashing red LED indicator that displays the alarm and battery status. Due to its innovative PowerLink tab, the Kidde i4618 is shipped with a battery installed and ready to go. This tab prevents drainage of the 9V battery until installation is complete The Kidde i4618 connects with up to 24 other compatible Firex smoke and heat alarms

 It is designed with dual ionization detection chambers, factory-sealed housing to prevent tampering and an attractive, low-profile design.This product is UL listed and comes with a five-year Kidde warranty. This smoke alarm comes in standard bulk packaging, and is not enclosed in retail box packaging.

Note: 1,000 ft. of wire can be used in the interconnect system.

  • Ionization Senses, Detects Invisible Fire Particles
  • Front Sliding Battery Door
  • Pre-Stripped Wiring
  • Connectable With up to 24 Devices
  • Dust Cover Reduces False Alarm Occurrences
  • 9 Volt Battery Backup
  • One Button test/hush to silence
  • Part Number: 21007584
  • Temperature for Operation: 40°F to 100°F
  • Dimensions: 5.6” diameter x 1.8” Depth
  • Power: 120 VAC, 9-Volt Battery Back-Up
  • Horn Loudness: 85db at 10 feet
  • Listing: U.L. 217
  • Detection: Dual ionization
  • Humidity Operation: 10% - 93% relative humidity
  • Weight: 5 LBS
5 year warranty thru Kidde
Customer Reviews

Worked fine

Used where the original alarm was discontinued. Worked fine.


on 01-15-2016 by Leon

Great Price

Top notch detector at a great price. no false alarms.


on 12-24-2015 by Scott

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Questions & Answers

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I bought 12 of I4618, one chirping, i have it hooked to hard wire and batteries; can i use it only with hard wire. OR do i have to have batteries as well....

by sherry P. on 09-07-2016

You can use without battery, the battery is there for if and when there is a power outage.

on 09-16-2016

I have a model i4618 and it has a slow flashing green light what does that mean? Also I think last night I heard a chirp. Do I need to replace the battery?

by Judy K. on 11-19-2015

Yes, try replacing battery first. If it continues, unit may need replaced.

on 11-29-2015

I need to replace firex Model fadc# 5000 120-1056F Is this the item I need or can you point me to the correct one? Thank you

by William S. on 11-17-2015

The I4618 is the correct replacement.

on 11-29-2015

*I have six older Firex Model 98310 smoke alarms. Will this unit replace the Firex model? Does it require an electrician to replace? Luis

by Luis F. from Lake Placid, Florida on 11-03-2015

If you are replacing AC hardwired Firex brand alarms manufactured prior to 2009, there is no current model that will fit the same wiring harness or mounting bracket. Replacing alarms will require first changing the mounting bracket, and then either changing the wiring harness, or for certain of these Firex models you can use the KA-F Adapter in order to avoid having to rewire to the new wiring harness. When you change one of these older alarms, you will need to replace ALL devices attached to it. This can easily be done without an electrician. Yes this the replacement for this Firex model.

on 11-29-2015

I need a replacement for the FireX model FADC. Is the Kidde i4618 smoke detector the replacement?

by M. D. on 02-17-2014

Per Kidde, the i4618 is a direct replacement for the FireX FADC.

on 03-10-2014

What is the replacement smoke detector for the FireX 120-1056C?

by Daniel H. on 02-11-2014

The replacement for FireX 120-1056C is the Kidde i4618 smoke detector.

on 03-11-2014

I am a bit confused. It seems Kidde makes many detectors that will replace my FireX adc unit. May I assume that they will all work, but the differance will be battery location, warrenty, size etc?

by richard W. on 12-14-2012

This is correct. There are several types of sensors depending on the installation location, th type of sensing, and each one's benefits.

This guide will give you better details before ordering:
Click here to view the Guide

on 12-14-2012

Are there units I can buy to replace Firex model G-18 without having to replace the wiring and bracket too?

by Brian M. on 09-08-2012

No, there are no compatible replacements to Firex items that will not require a new bracket / wiring harness

on 09-10-2012

All of our Smoke Detectors are firex 120-1072B, is this the replacement and how will it wire? Jim

by James S. on 08-21-2012

Yes, this is the replacement for your old smoke detectors. They will come with a wiring harness adapter and new mount bracket. Simply remove the old unit and mounting bracket, install the new mounting bracket, and attached the wiring harness to your previous connection. 

on 08-22-2012

I have a kidde model #1235 what is the replacement for this model

by Ron S. from 11758 on 07-30-2012

The Kidde i12020 is the direct replacement for the 1235.

Click here to view the Kidde i12020 

on 08-01-2012
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