• Firex Hush Smoke Alarm - P12040 - 21006371

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

    Product ID • P12040000000

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The Kidde Firex P12040 21006371 is a 120 volts powered photoelectric Smoke Detector alarm with 9 volts battery back up. This Firex advanced smoke alarm has the ability to function as a stand-alone unit or in an interconnected system. The Kidde Firex P12040 includes a test button, quick-connect power harness.

This Kidde Firex P12040 alarm uses photoelectric sensing technology. Photoelectric sensing alarms may detect visible particles (associated with smoldering fires) sooner than ionization alarms. Ionization sensing alarms may detect invisible fire particles (associated with flaming fires) sooner that photoelectric alarms.

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.

The Kidde Firex P12040 includes a 9 volt battery backup to provide continuous protection during a power failure and included a quick connect power harness to make installation simple.

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 P12040 unit. Otherwise, your old Firex units will NOT be able to communicate with this P12040 unit. This Kidde P12040 model can replace the old Firex model: Firex 4580, FPAD, PAD, PG40, 120-890 and 4480.

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 - PI2040 - 21006371 Techs and Specs

  • UPC Number
  • Model
  • Power Source
    120 Volts
  • Audio Alarm
    85dB at 10 Feet
  • Temperature Range
    40 Degrees F to 100 Degrees F
  • Humidity Range
    5% to 95% relative humidity (RH)
  • Sensor
  • Size
    5.6 inches diameter x 1.55 inches depth
  • Weight
    1 Pound
  • Interconnects
    Up to 24 Kidde Firex Devices
  • LED Green
    Receiving ac power
  • LED Red
    Alarm mode
  • Warranty
    10 year limited

Firex Hush Smoke Alarm Hard Wired - PI2040 - 21006371 Features

  • Photoelectric Sensor - Advanced photoelectric sensor may detect visible particles (associated with smoldering fires) sooner than ionization alarms
  • Battery Backup (9V Battery Included) - Provides continuous protection even during power outages
  • Test Button - Tests unit's electronic circuitry, horn and battery function
  • Quick Connect Power Harness - Makes installation fast and easy
  • Dust Cover - Protects sensor during construction
  • Battery Pull Tab - Eliminates battery installation time and keeps battery fresh. Red LED - Indicates that the smoke alarm is operating properly, HushTM, and alarm condition
  • Green LED - Indicates the presence of AC power