Kidde AC Hardwired Interconnect Smoke Detector Alarm with Hush | Model I12040

Price: $58.02
(as of Sep 23, 2026 16:47:25 UTC – Details)


The Kidde i12040A 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. 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. 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 10-year limited warranty. Part Number (Ordering Number): 21006378
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. 9V Battery Backup (included)
Fewer Callbacks – One button design for easy operation and less confusion. Operates Hush and alarm test. Battery run down protection will shut down alarm memory when AC power is not present, reducing low battery chirp. Dust cover protects sensor from contaminates during construction reducing nuisance alarms
User-Friendly Features – Tamper resist locking feature deters alarm theft. Alarm memory flashes red LED indicating which unit was the initiating alarm in interconnected system. One button design (operates Hush and test)
Interconnectable – Connect up to 24 devices (of which 18 can be initiating) including smoke, CO and heat alarms. See user’s guide for complete instructions
Ionization Sensing Technology
Customers find the smoke detector easy to install, taking 30 minutes to set up six units, and appreciate its compatibility with existing wiring harnesses and mounts. The product serves as an exact replacement for older Kidde models and offers good value for money. However, durability and battery life receive mixed reviews – while some units lasted a year, others died within 8 months, and the 9V battery typically lasts less than a year. Additionally, customers report issues with beeping and continuously flashing red lights.