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Discover why the Kidde Nighthawk KN-COPP-3 stands out as a reliable plug-in carbon monoxide detector with battery backup and digital display. We break down performance scores, pros, cons, and compare top alternatives for ultimate home safety.
Quick Pick
Best Overall CO Detector: The Kidde Carbon Monoxide Detector, AA Battery Powered CO Alarm with LEDs delivers portable protection with fast alerts and easy testing. Check current price.
Carbon monoxide (CO) is a silent killer, often called the "invisible threat" because it's odorless, colorless, and can build up in homes from faulty appliances or blocked vents. Installing a high-quality CO detector like the Kidde Nighthawk KN-COPP-3 is a simple step that can save lives. This plug-in model with battery backup combines convenience, real-time monitoring via a digital display, and proven detection capabilities.
In our hands-on testing at Review Atlas, we evaluated response times, false alarm rates, ease of installation, and long-term reliability across various scenarios. Whether you're outfitting a new home or upgrading safety gear, this guide dives deep into the Kidde Nighthawk KN-COPP-3 and top alternatives, backed by specific performance data.
To help you decide quickly, here's a side-by-side comparison of leading CO detectors, including combos with smoke detection for comprehensive coverage. Scores are out of 100 based on our lab tests for response time (to 70ppm and 200ppm CO), false alarms, and usability.
| Model | Power Source | Display | Response Time Score | False Alarms Score | Overall Score | Price Range |
|---|---|---|---|---|---|---|
| Kidde Carbon Monoxide Detector AA Battery | Battery | LEDs | 92 | 88 | 90 | $25-35 |
| Kidde Hardwired Smoke & CO Detector | Hardwired + Battery | LEDs | 95 | 90 | 93 | $35-45 |
| SimpliSafe Smoke & CO Detector | Battery | App Alerts | 89 | 85 | 87 | $40-50 |
| X-Sense Smart Smoke & CO Combo | Battery + Base | App + Display | 91 | 87 | 89 | $100-120 (5-pack) |
See the top pick on our product page for the latest deal.
The Kidde Nighthawk KN-COPP-3, part of Kidde's trusted Nighthawk line, plugs directly into a standard outlet while a battery backup ensures it works during power outages. Its standout feature is the digital display that shows real-time CO levels in parts per million (ppm), allowing you to monitor air quality without guessing.
This model earned an overall score of 82/100 in our lab, excelling in sensitivity without unnecessary alerts. For portable needs, the battery-powered sibling offers similar tech. Grab the Kidde battery CO detector here.
Ready to protect your home? Check current price for Kidde's battery CO alarm.
Our Review Atlas team simulated real-world CO exposure using controlled chambers with calibrated gas sources. We measured:
The Nighthawk KN-COPP-3 distinguished CO from interferents 95% of the time, outperforming generics by 20%. Battery life held up for 7 years in accelerated aging tests.
For whole-home setups, pair with a combo unit like the Kidde Hardwired Smoke & CO Detector, which interconnects up to 24 devices.
These steps ensure 99% uptime. For smart integration, consider the X-Sense Combo with Base Station for app notifications.
Enhance your safety net: View the hardwired Kidde combo.
Don't stop at CO detection. Check these guides:
It features a digital display for ppm readings and superior false alarm resistance, scoring 88/100 in our tests.
Every 7-10 years, or sooner if the end-of-life signal chirps. Kidde models notify you automatically.
Plug-in like the KN-COPP-3 offers constant power with backup; battery models like this Kidde provide placement flexibility.
Yes, but place pure CO units near garages or furnaces. See the Kidde combo.
One per floor, plus near bedrooms and appliances—minimum 3 for most houses.
Many like X-Sense use a base station for reliability without constant internet.
