Kidde smoke & carbon monoxide detector battery powered review & price


Does it really last for 10-year? Pretty standard looking smoke detector with CO warning, battery opening on the front. After installing the batteries, the voice option and beeps immediately told me what to expect if the alarm went off. The directions were very well written with pictures of where alarms should be located in the house. Know details in Kidde smoke & carbon monoxide detector battery powered review.

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Pros & Cons – Kidde smoke & carbon monoxide detector battery powered


  • Hush feature for false alarms
  • Battery is easy to change
  • Detects fire and CO threats
  • Voice warning system
  • Not hardwired
  • Uses same mounting system as other Kidde products


  • Batteries need to be replaced every six months

Specs – Kidde smoke & carbon monoxide detector battery powered

  • Model: KN-COSM-BA
  • Size: 5.6” in diameter x 1.8” depth
  • Temperature Range: 40˚F (4.4˚C) to 100˚F (37.8˚C)
  • Power Source: 2 AA Battery
  • Sensor: Smoke: Ionization, CO: Electrochemical
  • Audio Alarm: 85dB at 10ft
  • Humidity Range: 10%-95% relative humidity non-condensing
  • Weight: 13oz
  • Interconnects: No


The Kidde alarm is one of the more affordable combination units available at $45. Some models with more advanced features or integrated smart technology can cost $100 or more, but Kidde is a trusted brand

What is good in Kidde smoke & carbon monoxide detector battery powered?

Combined Carbon Monoxide and Smoke Alarm – A single unit can be installed where previously, two were needed. Reduces installation time and helps to keep home décor attractive.

Voice Alarm – Announces the hazard type detected thereby helping to speed up the correct reaction to the hazard detected. Alarm announces “Fire!” when a smoke or fire hazard is detected and announces “Warning Carbon Monoxide” when a CO hazard is detected.

Low Battery Warning – The unit warns of a low battery condition by announcing “low battery” and by initiating an alarm chirp and activating a flashing red LED.

Test/Reset Button – Tests alarm circuitry and triggers the voice announcement.

Battery Powered – Provides protection even during power outages when many fire and carbon monoxide incidents occur.

Hush® Feature – Temporarily silences nuisance alarms.

LEDs – Flashing green for normal operation and flashing red for alarm condition.

Battery Safeguard – The battery door will not close unless the batteries are properly installed.

Ionization Smoke Alarm Sensor

Kidde smoke & carbon monoxide detector battery powered review


‎It has a dimension of 1.8 x 5.6 x 5.6 inches and weighs only 12.3 ounces. The battery compartment will only shut if the batteries have been installed properly. Two LEDs are provided. Flashing green for normal operation and flashing red for alarm condition.

CO detectors should be placed between knee height and 5 feet.  If wall mounting, you need to keep the edge of the alarm a minimum of 4 inches from the ceiling and a maximum of 12 inches below the ceiling. If mounting on the ceiling, it needs to be a minimum of 4 inches from the side wall. 


It’s an ionization-sensing alarm, and it’s equipped with the company’s patented Hush technology, which allows you to essentially turn off the alarm for about 7 minutes when you know what is setting the alarm off, such as burning something in the oven (no need to rip it off the wall and rip the battery out to stop it from sounding!). It’s also designed to be tamper-proof.

Loud alarm

The 85-decibel alert was loud and clear enough that we were confident it’d wake us if we were sleeping. The resulting alarm was a voice prompt that told us it had detected “fire.” The alarm signal and voice warnings sound loud and clear, and it is simple to test the unit.

Hush feature

The Smart Hush feature silences the fire alarm for approximately 8 minutes. The green LED on the alarm will flash every 60 seconds in standby condition.


We first hung up the base, which attaches to the wall or ceiling using the included screws and anchors. Once the base was secure, we attached the detector itself. The detector screws into the base easily. To install the batteries (two AA), we just had to open the compartment door and slide them in. We like that changing the batteries doesn’t require removing the detector from the base. 

How does it work?

This alarm uses ionization sensing technology. Leading authorities recommend 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. 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 smoke & carbon monoxide detector battery powered customer review

Slight Difference Noted

After owning a Kidde joint CO2 & Smoke Alarm for about 7 years, I received an unexpected signal which I thought was an alert that the batteries were low. Upon changing to new batteries, & finding that wasn’t the problem, I decided what most all men do at that point; I finally read the instructions.
Based on the alarm signal code, it stated that the unit was malfunctioning, which actually wasn’t correct; the unit had reached it’s preprogramed time limit & it was considered to be out of date & needed to be replaced.

After a little research, I called & ordered a similar new unit direct. It arrived in a few days & I eagerly awaited its arrival even though I have several other alarms strategically placed throughout the house. My one disappointment was; while it showed that it used 3 AA batteries in the online ads, it really is only a 2 AA battery unit. I expect that the additional battery isn’t needed for proper operation, just wondering if the life expectancy will still be that same as my first unit?

By Capt. Jim at Kidde

* Residents of the below cities or states – Please Note: This Alarm is Not Compliant with your state’s 10-Year Sealed Battery Alarm Legislation Requirements: Oregon, California, Louisiana, North Carolina, Georgia, Maryland, New York, Wisconsin, Phoenix-Arizona, Philadelphia-Pennsylvania, Louisville-Kentucky, Indianapolis/Marion County, Indiana.

Alternate of Kidde smoke & carbon monoxide detector battery powered

First Alert SCO5CN

The First Alert SCO5CN not only detects smoke–it also detects unsafe levels of carbon monoxide (CO) in your home. Carbon monoxide is a colorless, orderless gas that can be deadly. Getting a CO detector is important because this gas is impossible to detect on your own.

On the front of the alarm, there are lights to let you know if there is a fire or CO emergency. Our favorite part is that the easy-access battery compartment makes it easy to change the batteries without removing it from the wall or ceiling. 


  • Alerts you when your smoke or CO detector goes off
  • Offers professional monitoring
  • Has voice alarm


  • No voice alerts

Editor’s recommendations

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