First Alert SC9120B Combination Alarm Review Reliable Hardwired Smoke and Carbon Monoxide Detector
First Alert SC9120B Combination Alarm Review Reliable Hardwired Smoke and Carbon Monoxide Detector
- The adapter plugs truly simplify replacing existing hardwired alarms, eliminating the need for rewiring.
- A 10-year battery backup ensures uninterrupted monitoring, even during power outages.
- The intelligent smoke sensing technology effectively minimizes false alarms.
- Indicator lights and an 85-decibel siren provide clear and immediate warnings for smoke or carbon monoxide detection.
- The end-of-life signal is a valuable safety feature, notifying when it’s time for a replacement.
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Description
Design and Build Quality
As I unboxed the First Alert SC9120B, the first thing that caught my attention was its sleek and compact design. It’s not bulky or overbearing, which is a big plus when mounting it on ceilings or walls. The white plastic finish blends seamlessly into most home interiors, making it inconspicuous yet functional. At just 0.63 pounds, it’s lightweight but doesn’t feel cheaply made. The materials seem sturdy enough to withstand years of service, and the overall build inspires confidence that this device is built to last.
The adapter plugs included in the package are a thoughtful addition. These made replacing my old hardwired alarm a breeze, saving me from the hassle of rewiring. The quick-connect wiring harness simplifies the installation process even further. It’s clear that a lot of thought went into ensuring this product is user-friendly and straightforward to set up.
Performance and Features
One of the standout aspects of this combination alarm is its dual functionality. It’s both a smoke alarm and a carbon monoxide detector, utilizing ionization smoke sensing technology and an electrochemical CO sensor. I tested the alarm by simulating smoke and CO conditions, and the 85-decibel siren was loud enough to grab anyone’s attention, even from another room.
The indicator lights on the face of the unit are another practical feature. These lights clearly display whether smoke or carbon monoxide has been detected, which can be crucial in an emergency. I appreciate the intelligent sensing technology that helps reduce nuisance alarms. Burning toast in the kitchen didn’t set it off, which was a huge relief compared to my old alarm that seemed to go off at the slightest hint of smoke.
Additionally, the latching alarm indicator is a lifesaver. It automatically identifies which unit initiated the alarm, even after the incident has passed. This feature eliminates any guesswork when trying to pinpoint the source of danger.
Key Benefits
- Combination smoke and carbon monoxide detection for comprehensive safety.
- Intelligent sensing technology minimizes false alarms.
- 85-decibel siren ensures that alerts are heard from various parts of the house.
- 10-year battery backup provides peace of mind, even during power outages.
Areas of Concern
While the First Alert SC9120B excels in many areas, there are a few caveats worth mentioning.
- The 10-year lithium battery is non-replaceable, which means the entire unit must be replaced once the battery’s lifespan ends.
- While installation was straightforward for me, homeowners unfamiliar with hardwired systems might find it slightly intimidating.
- The alarm sound, although effective, could be overwhelming in smaller spaces.
Usability and Maintenance
Using this alarm daily, I found that the test/silence button is intuitive and easy to access. Testing the unit takes seconds, and the ability to silence it during a nuisance alert is incredibly convenient. The end-of-life signal is another practical feature, ensuring you know when it’s time to replace the unit entirely.
This device also connects seamlessly with other First Alert or BRK alarms, creating a unified safety network throughout my home. When one alarm triggers, all connected alarms sound off, which is a game-changer for larger homes or multi-level residences.
Competitive Options
When comparing this alarm to other combination smoke and CO detectors, I noticed a few areas where it stands out. For instance, the Kidde KN-COSM-IBA offers similar dual detection but lacks the latching alarm indicator that’s so useful in identifying the source of an alert. On the other hand, the Kidde model is slightly more compact, which might appeal to those with space constraints.
The Nest Protect is another competitor that adds smart features like mobile notifications and voice alerts. However, it comes at a much higher price point and requires more technical setup. For those who prioritize affordability and straightforward functionality, the First Alert SC9120B strikes an excellent balance.
Price Performance
From a cost-effectiveness standpoint, this alarm delivers great value for its features. The 10-year battery backup alone ensures long-term reliability, while the quick-connect wiring and adapter plugs make it an excellent choice for replacing older hardwired systems. While it lacks the bells and whistles of some premium models, the core safety features are robust and dependable.
For anyone looking to enhance home safety without breaking the bank, this product offers true value. The combination of smoke and carbon monoxide detection, along with its user-friendly design, makes it a worthy investment for peace of mind.
Additional information
| Brand | First Alert |
|---|---|
| Style | Hardwired |
| Power Source | Corded Electric |
| Color | white |
| Product Dimensions | 0.07"D x 0.22"W x 0.22"H |
| Item Weight | 10.1 ounces |
| Alarm | Audible |
| Sensor Type | Electrochemical |
| Global Trade Identification Number | 00029054018786 |
| Material | Plastic |
| Number of Items | 1 |
| Manufacturer | First Alert |
| UPC | 029054018786 |
| Part Number | 1039807 |
| Item model number | SC9120B |
| Batteries | 1 Lithium Metal batteries required. (included) |
| Is Discontinued By Manufacturer | No |
| Size | No Size |
| Pattern | Alarm |
| Item Package Quantity | 1 |
| Included Components | Alarm, Battery |
| Batteries Included | Yes |
| Batteries Required | Yes |
| Battery Cell Type | Lithium Metal |
| Warranty Description | Warranty |
| ASIN | B07G95Z38H |
| Customer Reviews | Array |
| Best Sellers Rank | #25,308 in Tools & Home Improvement (See Top 100 in Tools & Home Improvement) #76 in Smoke & Carbon Monoxide Alarms |
| Date First Available | August 7, 2018 |














