• Firex Smoke Alarm - i4618 - 21007581

    - Hard Wired - 9 V Battery Back up - Ionization Technology - 120V AC/DC

    Product ID • I46180000000

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The Firex i4618 Smoke Alarm is an ionization 120V AC smoke alarm with battery back-up for single or multiple station use. It includes a Quick QuietTM False Alarm ControlTM feature which allows the user to quiet an unwanted alarm for up to 15 minutes. The Firex i4618 has a front loading battery door, 85 decibel horn, test switch and dual purpose LED indicator; constant green power on confirms AC power is present and the flashing red displays alarm/battery status. The Latching LED feature clearly identifies the smoke alarm that initiated an alarm in an interconnected system with a flashing red LED. The LED will remain flashing until the test button is depressed on that unit. Our unique PowerLinkTM Tab is designed to allow the smoke alarm to be shipped with the battery already installed. It keeps the door from closing until installation, which prevents the battery from draining prematurely. The installer simply removes the PowerLinkTM Tab, closes the door and tests the unit. This results in a faster installation time.

The dust cover eliminates nuisance call-backs by keeping construction dust and debris from causing false alarms.

The Firex i4618 smoke alarm mounts to any single or 4 inch octagon junction box or square-to-round drywall ring and has 8 inch long pigtails with a Quick Connect harness for permanent connection. The Firex i4618 is interconnectable with up to 11 other compatible Firex smoke alarms and 6 Firex heat, carbon monoxide or smoke/CO combo alarms for a total of not more than 18 Firex devices. When interconnected with other Firex smoke alarms, the unit that initiates an alarm will display a rapidly flashing red LED while the other interconnected alarm LED's remain extinguished.

Need to replace old Firex alarm?

Please Note. Unless you are replacing Firex FADC, ADC, and AD, you are required to replace ALL your old Firex alarms with this i4618 unit. Otherwise, your old Firex units will NOT be able to communicate with this i4618 unit. This Firex i4618 model can replace the following old Firex models:

4618 - 4418 -  ADC - 120-1072B - 4518 - 120-538B - 120-1182 (120-1182B) - 120-1072C - 5000 - 120-557B - FADC - AD - 120-1070 (120-1070B) - 120-1056E - 46182

Since old Firex and new replacement have different wiring harness, the existing wiring harness needs to be changed.

If you don't want to rewire, you need to get a quick convert adapter Kidde KA-F and perform 3-easy-step installation:
1.Replace the ceiling mounting bracket
2.Install KA-F adapter and attach existing wiring to the alarm.
3.The new alarm will now be interconnected and compatible with your Firex alarm system.

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Manuals & Docs

Technical Specs

Firex Hush Smoke Alarm Hard Wired - i4618 - 21007581 Techs and Specs

  • Model
  • Power Source
    120 Volts
  • Audio Alarm
    85dB at 10 Feet
  • Battery Backup
    9 Volts Battery
  • Temperature Range
    40 Degrees F to 100 Degrees F
  • Humidity Range
    10% to 93% relative humidity (RH)
  • Weight
    1 Pound
  • Interconnects
    Up to 18 Kidde Firex Devices
  • LED Green
    Receiving ac power
  • LED Red
    Alarm mode
  • Warranty
    10 year limited

Firex Hush Smoke Alarm Hard Wired - i4618 - 21007581 Features

  • NEW Alarm Locator - Red LED flashes until reset for quick, clear identification of the initiating alarm in an interconnected system
  • Front loading battery door - Makes battery changing simple
  • PowerLink™ Tab - Makes installation faster and easier than ever
  • Quick Quiet™ False Alarm Control™ - Quiets unwanted alarms for up to 15 minutes
  • NEW Visible Low Battery Indicator - Helps locate chirping unit
  • Interconnects with other Firex smoke and heat alarms - Compatible with other contractor preferred Firex devices
  • NEW Ramp-Up Test Horn - Allows you to test the unit without the earpiercing horn
  • Factory sealed housing - Prevents tampering and provides outstanding durability
  • Dust Cover - Eliminates nuisance call-backs
  • Attractive low-profile design - Favorite among consumers