Kidde's Nighthawk 900-0114 combines smoke and CO detection in a single unit. It uses a loud voice to alert occupants of either smoke or CO. In the case of fire, it simply sounds a recording: "Fire! Fire!" In the case of high CO levels, it sounds: "Warning! Carbon Monoxide!" A voice recording also announces low-battery conditions.

The 900-0114 is recommended for installation in most living areas, including hallways, bedrooms, and kitchens. Powered by 120-volt household current, these units are primarily suited to new construction--although they maybe be retrofitted to existing homes during remodeling. Aside from not relying solely on battery power, these AC-powered units can be interconnected with other compatible units so alarms sound throughout the house. In the event of smoke or CO detection during a power outage, the battery back-up takes over. Users may test smoke and CO sensors with a single button.

Of all the units we've looked at, this one has the most builder-friendly features. The unit is packaged in a sealed plastic bag to protect it from contamination. It also has a dust cap to prevent dust contamination during construction. The alarm has a gasket on the bottom to prevent ceiling drafts from blowing air away from the sensor. The quick connect plug cannot be accidentally disconnected, and the connector prongs are protected with cardboard during shipping.

Finally, on the Kidde Nighthawk 900-0114, just a pull of a plastic tab will activate the supplied battery.

Warranty
5 years limited