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Kidde Firex Hardwired Ionization Smoke Alarm

Model number
i4618AC

The Kidde Firex i4618AC is a 120V AC hardwired ionization smoke alarm from the Firex pro/contractor sub-brand, designed for use in interconnected systems. It supports up to 24 interconnected devices (18 initiating) including smoke, CO, and heat alarms. Alarm memory with a red LED identifies the initiating unit in the system. The Hush feature silences nuisance alarms. This Firex model is recognized on NFPA installation lists and has been replaced by the Kidde 20SAR.

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Model no.
i4618AC
Brand
Kidde
Category
Smoke Alarm Hardwired
Canonical URL
/kidde/smoke-alarm-hardwired/i4618ac-kidde-firex-hardwired-smoke-alarm/
Official page kidde.com →
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§ Specifications

#specifications
Product Type
Smoke Alarm
Alarm Type
smoke
Sensor Smoke
ionization
Power Source
hardwired-ac
Voltage
120
Battery Backup
Yes
Battery Type
9V
Battery Replaceable
Yes
Voice Alerts
No
Smart Wifi
No
App Connected
No
Ring Ecosystem
No
Interconnect
Yes
Interconnect Type
hardwired
Wire Free Rf
No
Max Interconnect Devices
24
Max Initiating Devices
18
Self Testing
No
Hush Feature
Yes
Smart Hush
No
Strobe
No
Egress Light
No
Alarm Db
85
Ul Smoke
UL 217
Warranty Years
10

§ What's Included

01 alarm unit
02 9V battery
03 wiring harness
04 mounting hardware
05 quick install guide

§ FAQ

What is the Firex brand?

Firex is a Kidde sub-brand targeting the professional contractor and builder channel. Firex alarms are recognized on NFPA installation lists and are commonly specified by building professionals for residential new construction and renovation projects.

How many alarms can be interconnected with the i4618AC?

The i4618AC supports hardwired interconnect with up to 24 compatible Kidde devices, with up to 18 initiating devices. All alarms in the system sound when one detects smoke, CO, or other hazards.

What does alarm memory do on the i4618AC?

The alarm memory causes the red LED to flash on the unit that first triggered an alarm, helping identify the initiating alarm in an interconnected system for troubleshooting and follow-up.

Is the i4618AC still sold?

The i4618AC has been discontinued. Kidde recommends the 20SAR DETECT-line model as a current replacement for Firex hardwired installations.

Does the i4618AC include a battery backup?

Yes. The i4618AC includes a 9V battery backup for continued operation during power outages. Replace the battery annually or when the low battery warning chirp sounds.