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Kidde Fire Sentry Smoke Detector, 9V Battery Powered Smoke Alarm, 4 Inch Compact Design

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$21.48

$ 8 .99 $8.99

In Stock

About this item

  • At only 4-inches in diameter, this is one of the smallest smoke detectors you can install in your home, RV, and mobile home
  • Basic ionization smoke alarm, affordable and simple to use to provide detection of dangerous smoke or fire
  • Operating on a 9-volt alkaline battery, the Kidde smoke alarm provides reliable detection of smoke or fire, even during power outages
  • Easy installation – this basic smoke detector requires no wiring
  • An 85-decibel alarm sounds & a red LED indicates the smoke detector is sensing smoke or fire
  • Test-Hush button makes it easy to test the smoke detector and silence false alarms that occur from cooking or shower steam
  • UL listed with a 3-year limited manufacturer warranty on alarm only (not a battery performance claim). Warranty begins when the alarm is powered on. If that date is unknown, it should be assumed that replacement is needed.


Product Description

The Kidde Fire Sentry Smoke Detector, 9V Battery Powered Smoke Alarm, 4 Inch Compact Design, model i9040, is a smaller designed, 4-inch diameter smoke detector that you can install in tight spaces in your home, your RV, or mobile home. The Kidde Smoke Detector uses ionization sensor technology to detect invisible fire particles (associated with flaming fires) sooner than photoelectric alarms. When smoke or fire is detected, an 85-decibel alarm will sound. The Kidde Smoke Detector is powered by a 9-volt battery, which provides easy installation since the alarm requires no wiring, plus coverage during a power failure. A red LED indicates that the smoke detector is sensing smoke or fire. A test-hush button allows you to test the battery operations as well as silence nuisance alarms that may occur from cooking or shower steam. The Kidde Smoke Detector will chirp when it's time to replace the battery. Install a smoke detector & carbon monoxide detector on every level of your home and near bedrooms to help keep your family safe from fire & poisonous gas. UL Certified with a 3-year limited manufacturer's warranty. Meets requirements of UL 217, NFPA72 (chapter 11 2002 edition), NFPA101 (One and two-family dwellings), and Federal Housing Authority (FHA).

Amazon.com

Designed to help protect you and your family from the dangers of smoke and fire, the Kidde i9040 Fire Sentry Compact Smoke and Fire Alarm, Ionization Sensor is a compact, battery-operated unit that provides continuous protection, even during power outages. UL-listed, it uses ionization technology to detect smoke and fires as soon as they start, providing both extra escape time and peace of mind. callout top i9040 Fire Sentry Compact Smoke and Fire Alarm At a Glance: Battery-operated alarm offers continual operation, even during power outages Protects your family in case of a home fire Uses ionization technology to detect even invisible fire particles Includes 9-volt battery Three-year limited warranty callout top i9040 Fire Sentry Compact Smoke and Fire Alarm Each alarm provides a range of user-friendly features for easy operation and maintenance. View larger. i9040 Fire Sentry Compact Smoke and Fire Alarm Use the test button to check the alarm's circuitry, horn, and battery function. View larger. Smoke Alarms Prevent Home Fire Deaths Every year, 70 percent of all home fire deaths occur in homes with no alarms or no working alarms, while nearly one quarter of smoke alarms in reported fires are not working. Installing smoke alarms like the i9040 in your home can provide reliable protection in case of fire. And because the i9040 offers several user-friendly features, you'll always know when it's working properly, and when the batteries need to be replaced. Compact Unit Provides Protection Against Home Fires Measuring just four inches in diameter, the i9040 is smaller and more discrete than traditional smoke alarms, which makes it an ideal choice for smaller spaces or for blending in with your decor. It installs quickly without wires, and includes a test button that allows you to periodically check the circuitry, horn, and battery function. Also, a chirping sound makes it clear when it's time to replace the battery. Ionization Sensor Technology To ensure early detection of fires, the i9040 use ionization sensing technology Ionization sensing alarms may detect invisible fire particles (associated with fast flaming fires) sooner than photoelectric alarms. Photoelectric sensing alarms may detect visible fire particles (associated with slow 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 fires that can occur within the home. Compliancy and Warranty Information The i9040 alarm is UL listed and is backed by a three-year limited warranty. About Kidde: A UTC Fire and Security Brand Renowned for global leadership in fire detection and suppression, Kidde provides solutions ranging from portable fire extinguishers to advanced industrial controls such as flame detection and explosion suppression systems. Kidde is a UTC Fire and Security brand, with a history that's rich with innovations, from the patent of the Chubb Detector Lock in 1818 to the development of the world's first wireless networked smoke detectors in 2004. What's in the Box Kidde i9040 Smoke and Fire Alarm, 9-volt battery, mounting hardware, and installation guide. i9040 Fire Sentry Compact Smoke and Fire Alarm Keep your family safe by placing alarms and extinguishers in each area of the house, and by having a fire escape plan. Click here for a detailed image.


Katherine B.
2025-09-04 12:38:40
Great product. Great price. I’ve had this same smoke detector in my home for 20 years and it finally wore out. I didn’t want to mess with mounting a new style. Even though the new one (I ordered two) comes with the mount, I was able to attach the new smoke detectors to old mount.
Kyle William Loshure
2025-08-31 17:27:06
Mounting underneath my mailbox so when they light up the smoldering fire all night long with stagnant air that the fire department is protecting with the sheriff department it might get many other to call the fire in . Worth a try Great value and batteries included Easy to installLouder than my siren I had on all night that didn’t work like contacting fire department They got a new plan that’s allowing the corrupt government to keep methville Florida open for business It’s insane here
BS AZ
2025-08-21 16:46:33
Good, basic smoke detector to put up in my camper trailer. Even fit the mount that was already in there.
glennwolv
2025-08-11 13:11:23
Neede to replace the smoke detector in my studio apartment. This was perfect for my needs and affordable. Arrived in 2 days, was easy to install, came with a battery. Easy peasy.
Audiophile MB (Marco B.-NYC)
2025-07-22 15:43:49
Unfortunately, uses 9 volt battery (got tired of buying those expensive batteries, so I bought rechargeable NiMH 9v charger right here on amazon,{Caution Lithium Ion batts will NOT work ionization type smoke detectors / I've already made that mistake}.....very inexpensive for 2 bats and charger, BTW)…..so, since I'm a landlord and have 3 apartments here in Brooklyn that mandates I supply smoke detectors and this one fits the bill. I have it in my own apartment and it works quite well; just keep about 8 to 10 feet away from cooking stove and at a height where you can push the reset button! Ionization detectors are far more accurate at detecting "fire" smoke as they are not infra red operated! Kidde is a superb brand that I've been using for years and now I can just buy ONE when I need to replace every 7-10 years instead of a card of 2 or 3 like at Costco or big box store! Very inexpensive for what it is and trust me when I say I've bought too many of these that they almost seem disposable. BTW,...ALL of the smoke detectors now made have a lifetime of 7-10 years before you have to toss them! DEFINITELY WORTH THE COIN!UPDATE: 2/8/20....all of these are still working like gangbusters AND the price is now all of $4. Yep, NOT a typo $3.84 to be exact! Now that really IS a no brainer!Hey folks,...I spend a fortune in time, energy and money on stuff that I buy and use here on amazon so, if this review was HELPFUL,....well you know what to do! Thanks fellow consumers!UPDATE: 5/16/21.....apparently these have gone up in price to approx. $11.00,.....don't you just love human nature's ability to pique the "greed" factor out in so many of our fellow human beings?? I willl certainly buy as few things as possible from this point forward. I am really NOT predisposed to pay for private Taj-Mahal reflecting pools on private islands OR expensive divorces. Are You??I guarantee this addendum will not make it past amamzon big brother censor! You really should be red and bald faced ashamed at what you do with price manipulation. It's not ALL trade embargoes....it's lets get filthy rich at our LOYAL customers' expense, eh Jeff???
Missouri Rancher
2025-06-27 16:36:25
Small and easy to install smoke detector is also as sensitive to smoke as the much more expensive ones. Worked well in actual smoke situation. Highly recommend.
Joyce
2025-05-17 15:25:39
Easy to put up, works fine, it’s not real big and the sound would definitely wake me if it went off. I had another just like it. The only reason I replaced, it says to replace after 10 years like most do.
AJ
2025-05-05 13:52:37
I purchased these as gifts for my kids. I had previously purchased sealed smoke alarms and didn't find them to last for very long. I had been looking for alarms that batteries were replaceable! My kids loved them, even though they were part of Christmas gifts. I purchased a sizable amount and we have replaced all alarms and feel protected and safe in our homes. Great shipping, great prize and dependable
martin
2025-04-01 15:47:24
good quality product alarm activates as per design
Oreos thoughts
2025-02-12 10:17:57
Exact replacement
KAMAL
2024-12-31 10:56:33
I tried many times with cigarette and other low flame smoke it does not activate only a large quantity of smoke can activate it
Ishita
2024-12-25 18:09:30
Completely useless as a fire prevention/intimation device. Do not buy. The alarm is triggered only by close contact of fire and a large volume of smoke
Kamal
2024-12-16 11:08:25
It was working fine for a month and then it started beeping without any smoke or heat. It's waste of money