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Kidde Hardwired Smoke & Carbon Monoxide Detector, AA Battery Backup Smoke Alarm, Interconnectable, LED Warning Light Indicators, 2 Pack

  • Based on 466 reviews
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Availability: In Stock.
Fulfilled by Amazon

Arrives Wednesday, Sep 3
Order within 2 hours and 41 minutes
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Style: 9th Edition


Size: 2 Pack


Features

  • 2-IN-1 DETECTION: Alerts you to both smoke & carbon monoxide (CO) using a single, cost-effective detector.
  • HARDWIRED & 2 AA BATTERY BACKUP (Included): Operates on 120V AC wiring (installed in the ceiling) with 2 AA alkaline batteries that provide battery backup coverage during power outages.
  • ENHANCED SENSING TECHNOLOGY: Reduces false smoke alarms often caused by cooking. Comprehensively tested to meet the latest UL standards, meets UL 217 9th Edition, UL 2034 4th Edition, & FCC standards.
  • INTERCONNECT CAPABILITY: When one alarm sounds, they all sound, so you can get out faster. (Different models offer different interconnection options and requirements. See User Guide for more info.)
  • SELF-TESTING ALARM: Internal components ensure alarm is always operating as expected. Not a substitute for a manual push test, perform a button test once per week to verify alarm operation.
  • 3 LED NOTIFICATIONS: LED lights indicate alarm status, green = normal operation, amber = operating error, red = smoke or carbon monoxide detected & a loud 85-decibel alarm will sound.
  • TEST & HUSH BUTTON: Makes it easy to test the 5-inch combination detector and silence false alarms, should they occur.
  • 10-YEAR LIMITED WARRANTY: Warranty begins when the alarm is powered on. If that date is unknown, it should be assumed that alarms should be replaced.

Description

Experience the next level of fire safety with the Kidde Hardwired Smoke & Carbon Monoxide Detector, AA Battery Backup, Interconnectable, LED Warning Light Indicators, 2 Pack, model 30CUAR. This smoke & CO detector has enhanced sensing technology that reduces false alarms often caused by cooking and sends fast alerts that help give your family more time to get out safely. To detect carbon monoxide, an electrochemical sensor is used. This alarm offers a modern 5-inch design ideal for all living spaces such as living rooms, hallways, kitchens, & bedrooms. Comprehensively tested and designed to the latest UL standard for safety and reliability, the 5-inch smoke & CO alarm is powered by 120V AC wiring with 2 AA alkaline replaceable backup batteries (included) for continual detection even during outages. Batteries should be replaced every 6 months or when the alarm sounds a low battery chirp. In addition, it’s self- testing and easy to install with the included twist-and-click mounting bracket. This Kidde combination alarm is equipped with end-of-life notifications that will beep to remind you it’s time to replace it at the of its 10-year lifespan. Meets requirements of 9th Edition UL 217, UL 2034 4th Edition, FCC, and CSFM.

Brand: Kidde


Style: 9th Edition


Power Source: Hardwired


Color: White


Product Dimensions: 1.88"D x 5"W x 5"H


Item Weight: 12.8 ounces


Alarm: Smoke and Carbon Monoxide Alarm


Operating Humidity: 10 to 95% relative humidity (RH), non-condensing


Upper Temperature Rating: 100 Degrees Fahrenheit


Sensor Type: Photoelectric, Electrochemical


Brand: ‎Kidde


Style: ‎9th Edition


Power Source: ‎Hardwired


Color: ‎White


Product Dimensions: ‎1.88"D x 5"W x 5"H


Item Weight: ‎12.8 ounces


Alarm: ‎Smoke and Carbon Monoxide Alarm


Operating Humidity: ‎10 to 95% relative humidity (RH), non-condensing


Upper Temperature Rating: ‎100 Degrees Fahrenheit


Sensor Type: ‎Photoelectric, Electrochemical


Material: ‎Plastic


Number of Items: ‎1


Manufacturer: ‎Kidde


UPC: ‎047871328482


Part Number: ‎21032848


Item model number: ‎30CUAR


Size: ‎2 Pack


Shape: ‎Circular


Item Package Quantity: ‎1


Included Components: ‎AA batteries, Mounting Hardware, Two Alarm, User Guide


Batteries Included?: ‎Yes


Batteries Required?: ‎Yes


Battery Cell Type: ‎Alkaline


Date First Available: September 9, 2024


Frequently asked questions

If you place your order now, the estimated arrival date for this product is: Wednesday, Sep 3

Yes, absolutely! You may return this product for a full refund within 30 days of receiving it.

To initiate a return, please visit our Returns Center.

View our full returns policy here.

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Top Amazon Reviews


  • Excellent replacement detectors
Size: 2 Pack
I ordered 4 of these to replace my 10-year old Kidde interconnected voice smoke/carbon dioxide detectors. The old ones were at end of life and they were making a big, annoying fuss about it. These are the current equivalent to my previous units. The power plug is different unfortunately, Kidde did drop the ball there. They were easy enough to switch out though, just unscrew the existing wire nuts and reinstall with the new wire harness. The mounting plate is the same size as the units being replaced so no paint touchup was required. The new units themselves are slightly smaller however. A nice upgrade these new ones feature is the AA battery backup rather than the expensive 9V battery backup, a welcome change. All 4 of the new units I purchased tested good and are working fine. No false alarms or issues yet. I will update this review if anything changes. Oh, and a great price here on Amazon as compared to local big box stores. ... show more
Reviewed in the United States on July 31, 2025 by Kory

  • Easy to Install and Works Great
Size: 2 Pack
I purchased this hardwired smoke and carbon monoxide detector and installed it myself with no issues. The instructions were clear, and the wiring matched up perfectly with my existing setup. It only took about 10 minutes to swap out my old unit. Once installed, it tested correctly right away. I really like that it combines both smoke and CO detection in one device, which saves space and adds peace of mind. Overall, an easy DIY project and a solid upgrade for home safety. ... show more
Reviewed in the United States on August 28, 2025 by Monica R.

  • replace every 10 years
Size: 2 Pack
good combo CO & smoke detectors. I replaced all 12 in my house as you are meant to every 10 years. good quality and complete wiring harness and very easy to replace. functions well,
Reviewed in the United States on July 21, 2025 by DIYer

  • Accuracy of sensor
Size: 2 Pack
For some reason last night the alarm went off for 10 seconds and then off don't know why alarm sounded .
Reviewed in the United States on April 4, 2025 by Al Cempel

  • Newer replacement product requires complete removal of expired unit to replace .
Size: 2 Pack
These are very well made, and I was able to replace one of my 7 units in my house that decided to go rogue after 10 years of service! These came with the updated wiring harness, so we replaced the whole unit, very easily. It will require a ladder, screwdriver, fresh wire nuts, and some knowledge of electricity to prevent electrocution. All in all, fairly easy to install. Great replacement product, Kidde! ... show more
Reviewed in the United States on August 8, 2025 by June Vivion

  • Great Purchase
Size: 2 Pack
Comes with the wiring adapter and is a great price for two. It's easy to change out, even if you have no experience with electrical. Love that it's for smoke & carbon monoxide.
Reviewed in the United States on August 26, 2025 by Amelia Jee

  • No More Beeping
Size: 2 Pack
Easy replacement. Even after replacing AA batteries in old unit it still beeped. Installed to replace old alarms that were 10 yrs old. Had to swap wiring connection, 3 wires with wire nuts (included). 5 minutes to replace the unit. No more beeping
Reviewed in the United States on August 19, 2025 by CPIJ

  • Great Replacement Fit
Size: 2 Pack
I saw a few review that were looking for replacement info. Hopefully this helps. These were replacements to my Kiddie Model#KN-COSM-1B. I also had to order the attachments (20-9003). They both work great together. DO NOT let the electric company tell you they have to rewire because the attachment is too bulky. I had my handman come over and put the attachment on the new detectors and it went right in with no problem. ... show more
Reviewed in the United States on August 3, 2025 by CB

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