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Kidde i4618 Firex Smoke Alarm Hardwired w/ Battery Backup and Hush Item 21007581

by Kidde
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SKU i4618_OB
Kidde i4618 Firex Smoke Alarm Hardwired w/ Battery Backup and Hush Item 21007581
Brand new. Box has been opened.


Front-loading battery door allows you to change the battery without removing the alarm from mounting bracket
  • Provides a Hush™ feature to quickly silence nuisance alarms
  • Tamper resist locking feature deters alarm theft
  • Alarm memory flashes red LED indicating which unit was the initiating alarm in interconnected system.
  • Battery backup provides protection in case of power failure
  • Interconnectable with up to 24 devices (of which 18 can be initiating) including smoke, CO and heat alarms. See user’s guide for complete instructions.
  • Part # (Ordering Number): 21007581
  • Previous part #/model #: 120-1182, fadc, 120-538b, i5000


The Kidde i4618 is an AC/DC powered, ionization smoke alarm that operates on a 120V power source with 9V battery backup. This alarm uses ionization sensing technology. Ionization sensing alarms may detect invisible fire particles (associated with flaming fires) sooner than photoelectric alarms. Photoelectric sensing alarms may detect visible particles (associated with smoldering fires) sooner than ionization alarms.

The front-loading battery door allows user to change the battery without removing the alarm from the mounting bracket making battery replacement easy and convenient. This smoke alarm is available in a 6-piece cut case with tray for easy display as well as a 6-piece bulk pack for contractors and property owners. This unit is a UL Listed product with a 5-year limited warranty. Kidde strongly recommends that both ionization and photoelectric smoke alarms be installed to help insure maximum detection of the various types of fire that can occur within the home.


Easy Installation
• Front battery pull tab allows battery activation without removing alarm from mounting bracket.
• Large mounting base makes mounting easier, protects surface paint from dirt and covers imperfections.
• Pre-stripped wiring harness with easy off cap does not require stripper tool. Tinned strands increase conductivity and wire nut grip.

Fewer Callbacks
• Large centrally located Test/Hush® alarm control button.
• Dust cover protects sensor from contaminates during construction reducing nuisance alarms.

User-Friendly Features
• Easy access front loading battery door.
• Battery backup provides protection in case of power failure.
• Interconnectable with up to 24 devices (of which 18 can be initiating) including smoke, CO and heat alarms. See user’s guide for complete instructions.


Technical Specifications

Model: i4618
UPC: 0-47871-07581-2
Power Source: 120VAC (80mA Max)
Sensor: Ionization
Audio Alarm: 85dB at 10ft
Temperature Range: 40°F (4.4°C) to 100°F (37.8°C)
Humidity Range: Up to 85% relative humidity (RH)
Size: 5.6 in diameter x 1.8 in depth
Weight: .5lbs
Interconnects: Up to 24 Kidde devices
LED: Green, receiving ac power,Red, 4 modes of operation
Warranty: 5 year limited

Architectural and Engineering Specifications

The smoke alarm shall be Kidde Model i4618 or approved equal. It shall be powered by a 120VAC, 60Hz source along with a 9V battery backup. The unit shall incorporate an ionization sensor with nominal sensitivity of 0.50 to .92%/ft. The temperature operating range shall be between 40°F and 100°F (4°C and 38°C) and the humidity operating range shall be up to 85% relative humidity. The smoke alarm can be installed on any standard single gang electrical box, up to a 4” octagon junction box. The electrical connection (to the alarm) shall be made with a plug-in connector. A maximum of 24 Kidde devices can be interconnected in a multiple station arrangement. The interconnect system must not exceed the NFPA (National Fire Protection Association) limit of 18 initiating devices, of which 12 can be smoke alarms. With 18 initiating devices (Smoke, heat, CO, etc), interconnected, it is still possible to interconnect 6 strobe lights and/or relay modules. The alarm shall provide optional tamper resistance that deters removal of the unit from the wall or ceiling. No additional pieces shall be required to activate this feature. The alarm shall include an easy access battery compartment that is opened and closed by sliding the battery door. The 9V battery carrier will ensure proper battery backup protection by not allowing the battery door to close if the battery is placed in the unit incorrectly or if a battery is not present. The unit shall include a piezoelectric horn that is rated at 85 decibels at 10 feet. The unit shall include the Smart HushTM feature that silences the unit for approximately 8 minutes if a nuisance condition occurs. The unit shall incorporate red and green LED indicators. The green LED (when illuminated) indicates the presence of AC power. The red LED (located under the TEST/Hush button) has four modes of operation: Standby Condition: The red LED will flash every 30-40 seconds to indicate that the smoke alarm is operating properly. Alarm Condition: When the alarm senses products of combustion and goes into alarm the red LED will flash one flash per second. The flashing LED and pulsating alarm will continue until the air is cleared. When units are interconnected, only the red LED of the alarm that senses the smoke or is being tested (the originating unit) will flash. All other units in the interconnected system will sound an alarm but their red LED’s will NOT flash. Alarm Memory: This smoke alarm is equipped with an alarm memory, which provides a visual indication when an alarm has been activated. The red LED will illuminate for about 1.5 seconds every 16 seconds to indicate the memory condition. Smart HushTM Mode: The red LED will illuminate for 1.5 seconds every 8 seconds, indicating the smoke alarm is in the Smart HushTM Mode. The unit shall at a minimum meet the requirements of UL217, NFPA72, and (chapter 11), The State of California Fire Marshall, NFPA101 (0ne and two family dwellings), Federal Housing Authority (FHA), Housing and Urban Development (HUD).

Installation of Smoke Alarm

The smoke alarm should be installed to comply with all local codes having jurisdiction in your area, Article 760 of the National Electric Code, and NFPA 72. Make certain all alarms are wired to a single, continuous (non-switched) power line, which is not protected by a ground fault interrupter. A maximum of 1000 ft. of wire can be used in the interconnect system. Use standard UL listed household wire as required by code.