BRK Hardwired Smoke and Carbon Monoxide Alarm SC9120B — Ionization Smoke + CO Sensor, 9V Backup

The BRK SC9120B is a hardwired, interconnectable alarm that combines ionization smoke detection and carbon monoxide sensing with a 9V battery backup for continuous home protection.

This single unit monitors two different household hazards—fast-flaming smoke and invisible carbon monoxide—so you don't need separate devices. Designed for permanent 120V wiring with an included quick plug-in connector and battery backup, the SC9120B is built for reliable operation, easy installation, and clear notifications when something goes wrong.

How does the SC9120B detect both smoke and carbon monoxide?

The SC9120B integrates an ionization smoke sensor to spot fast-flaming fires and a dedicated carbon monoxide sensor to sense the odorless gas. Each hazard triggers its own distinct audible and visual alert so you can quickly understand the type of danger.

• Dual sensors: ionization for flaming fires; CO sensor for carbon monoxide.
• Separate audible tones and visual latching indicators for smoke vs CO.
• Microprocessor control to reduce false alarms while maintaining sensitivity.

Can multiple units be connected together across a home?

Yes—the SC9120B supports hardwired interconnection so one triggered alarm can alert every connected unit. It works with up to 18 compatible devices in a network, including other BRK and First Alert hardwired alarms and select notification accessories.

• Interconnectable across a circuit: up to 12 other smoke alarms and 6 notification devices.
• Power indicators show which unit initiated the alarm for quick locating.
• Compatible with bells, horns, repeaters and door closers for expanded systems.

What features make the SC9120B practical for everyday use?

The unit includes a one-button test/silence control, tamper-resistant locks, and an automatic self-test routine to keep maintenance simple. A 9-volt battery is included so the alarm continues to function during power outages.

• Single test/silence button to quiet nuisance alerts and perform checks.
• Battery drawer and mounting bracket locks for tamper resistance.
• AC power and alarm indicator lights plus low-battery chirp and missing battery tab alert.

How easy is installation and long-term upkeep?

The SC9120B ships with a universal mounting bracket and a quick plug-in power connector to streamline wiring tasks, making it contractor- and homeowner-friendly. Routine upkeep is limited to the included battery replacement and periodic testing using the built-in button.

• Quick plug-in connector for straightforward hardwire hookup.
• Universal mounting bracket fits standard junction boxes and locations.
• Auto internal tests plus manual test button for regular verification.

Who is this for? The BRK SC9120B is suited for homeowners, landlords, and builders who want a single, hardwired device to monitor both smoke and carbon monoxide across living spaces. It's ideal where interconnection with other alarms is required—near bedrooms, in hallways, and throughout multi-room systems—offering a dependable backup battery and tamper-resistant features for family and property protection.

• Features: Superior CO sensor; ionization smoke detection
• Included: 9V battery; universal mounting bracket; quick-connect power plug
• Compatibility: Interconnects with BRK and First Alert hardwired alarms
• Warranty: 7-year limited warranty