Kidde KN-COB-B-LP Nighthawk Carbon Monoxide Alarm
- 3 AA batteries included, battery operated
- 85 decibels at 10 feet alarm
- Electrochemical CO sensor, meets UL requirements
- 7 year end-of-life warning to replace the unit
- Green and red LEDs, green flashes every 30 seconds
- Wall or tabletop mounting
- Seven year limited warranty
Last refreshed Sep 8, 2026 · Based on the Amazon listing and published specifications, not hands-on testing.
A simple battery-powered CO alarm that works through power outages and installs anywhere without wiring. No digital readout or interconnect is listed, so it only signals that CO is present, not how much.
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ASIN: B001P3UO3YCategory: Carbon Monoxide Detectors
Overview
Renters and homeowners without hardwired alarm circuits get carbon monoxide protection from a unit that runs entirely on batteries, so it stays on during power outages. The Kidde Nighthawk uses an electrochemical sensor, a test-reset button and two status lights, and it mounts on a wall or stands on a tabletop.
Battery power is the reason to buy: no outlet or wiring decides where it goes, and an outage does not silence it. The limit is information, since status comes from two lights and a beep pattern instead of a reading on a screen.
Who it's for
Bedrooms, hallways and rentals without spare outlets are the natural home for it. Households that want linked alarms throughout the house or a live CO reading should look at a connected or display model.
Pros and cons
- Runs through power outages on batteries
- Batteries included in the box
- Test-reset button checks operation
- Wall or tabletop placement
- Digital CO display not listed
- CO only, no smoke detection
- Whole unit must be replaced at end of life
- Listing mixes LP and LS model codes
Performance notes
Detection relies on an electrochemical sensor that reacts to carbon monoxide in the surrounding air, so placement near sleeping areas governs how early you hear it. Because the unit draws only on its batteries, it monitors during outages when plug-in-only units go dark. The beep pattern repeats in cycles, and the test-reset button resets the alarm.
Specifications
| Brand | Kidde |
|---|
Frequently asked questions
How do you install the Kidde Nighthawk battery CO alarm?
It needs no wiring. The listing describes multiple mounting options for a wall or a tabletop, and three AA batteries come in the box. Mounting screws are not itemized in the box contents.
Does the Kidde Nighthawk KN-COB-B-LP plug into an outlet?
No. It is battery operated only, which is why it continues to monitor during power outages.
What does the Kidde Nighthawk do when it detects carbon monoxide?
A red LED pulses and the alarm sounds four short beeps, five seconds of silence, then another set of four short beeps.