1. Introducció
The First Alert BRK 9120LBL is a hardwired smoke detector designed to provide early warning of smoke and fast-flaming fires. This unit features an ionization sensor and includes a 10-year sealed battery backup, ensuring continuous operation even during power outages. Adapter plugs are provided for easy replacement of existing hardwired alarms without requiring rewiring. This manual provides essential information for proper installation, operation, and maintenance to ensure optimal performance and safety.

Imatge 1: Frontal view of the First Alert BRK 9120LBL Hardwired Smoke Detector.
2. Informació important de seguretat
Please read and understand all instructions before installing and operating this smoke detector. Failure to follow these instructions may result in property damage, injury, or death.
- ADVERTIMENT: Turn off power at the circuit breaker before beginning installation or maintenance.
- No pinteu el detector de fum. La pintura pot obstruir les cambres de detecció i impedir que l'alarma funcioni correctament.
- Test the smoke detector weekly to ensure proper function.
- This smoke detector is designed for use in single-family residences.
- Replace the unit immediately if it is damaged or not functioning properly.
For additional safety information, refer to local building codes and fire safety guidelines.
3. Contingut del paquet
Verifiqueu que tots els elements estiguin inclosos al vostre paquet:
- First Alert BRK 9120LBL Smoke Detector
- Suport de muntatge
- Adapter Plugs (various types for compatibility)
- Cargols i ancoratges de muntatge
- Manual d'instruccions (aquest document)

Image 2: All components included with the First Alert BRK 9120LBL smoke detector.
4. Instal·lació
Proper placement and installation are crucial for the effective operation of your smoke detector. Follow these steps carefully.
4.1 Col·locació recomanada
Install smoke alarms on every level of your home, including the basement, and in every bedroom. For optimal protection, place alarms in hallways outside sleeping areas and in living rooms.
Video 1: This video illustrates recommended placement for smoke alarms and other fire safety devices within a home.
4.2 Cablejat i muntatge
- Apagueu l'alimentació: Before starting, ensure the power to the circuit where you are installing the alarm is turned off at the main electrical panel.
- Remove Old Alarm (if applicable): If replacing an existing alarm, carefully disconnect it from the wiring and remove its mounting bracket.
- Col·loqueu el suport de muntatge: Secure the new mounting bracket to the ceiling or wall using the provided screws and anchors. Ensure it is firmly attached.
- Connecteu el cablejat: Use the appropriate adapter plug to connect the smoke detector to your home's electrical wiring. Match the wire colors (typically black to black, white to white, and orange/red for interconnect if applicable). The adapter plugs are designed for easy replacement without rewiring.
- Activate Battery Backup: The unit comes with a 10-year sealed lithium battery. Ensure the battery is activated by pulling the tab or following the instructions on the unit.
- Connecteu el detector de fum: Alineeu el detector de fum amb el suport de muntatge i gireu-lo en sentit horari fins que quedi ben encaixat.
- Restaura l'alimentació: Torneu a encendre l'alimentació al disjuntor.
- Prova l'alarma: Press and hold the Test/Silence button until the alarm sounds. This confirms the unit is receiving power and functioning correctly.

Image 3: A person installing the smoke detector mounting bracket on a ceiling.

Image 4: The back of the smoke detector showing the wiring connections and adapter plug interface.
Vídeo 2: Aquest vídeo ofereix una visió generalview of the First Alert 9120LBL smoke alarm, including its quick connect plug and battery backup features.
5. Funcionament
The First Alert BRK 9120LBL smoke detector is designed for simple operation and clear alerts.
5.1 Botó de prova/silenci
The large button on the front of the alarm serves two primary functions:
- Prova: Press and hold the button to test the alarm's electronic circuitry, horn, and battery. The alarm will sound if functioning correctly.
- Silenci: In case of a nuisance alarm (e.g., from cooking smoke), press the button to temporarily silence the alarm for several minutes. The alarm will automatically reset after the silence period if the smoke has cleared.

Image 5: The smoke detector highlighting the 10-year battery backup and the Test/Silence button.
5.2 Indicadors d'alarma
The alarm uses both audible and visual indicators:
- So d'alarma: A loud, 85-decibel alarm will sound in the presence of smoke. If interconnected with other compatible alarms, all connected alarms will sound.
- Indicador LED: A red LED light indicates the status of the alarm (e.g., normal operation, alarm, low battery, malfunction). Refer to the detailed signal patterns in the full user manual for specific meanings.
6. Manteniment
Un manteniment regular garanteix que el detector de fum es mantingui en condicions òptimes de funcionament.
6.1 Proves setmanals
Test your smoke detector at least once a week by pressing and holding the Test/Silence button until the alarm sounds. If the alarm does not sound, refer to the Troubleshooting section.
6.2 Neteja
Clean your smoke detector at least once a month. Use a soft brush or vacuum cleaner attachment to remove dust and debris from the vents. Do not use water or cleaning solvents.
6.3 10-Year Sealed Battery
This smoke detector is equipped with a 10-year sealed lithium battery that does not require replacement for the life of the alarm. When the battery reaches the end of its life, the unit will emit an end-of-life signal (a specific chirp pattern) indicating it's time to replace the entire smoke detector.
7. Solució De Problemes
If your smoke detector is not functioning as expected, consult the following common issues:
| Problema | Causa possible | Solució |
|---|---|---|
| Alarm sounds intermittently (chirping) | Senyal de final de vida útil | Replace the entire smoke detector unit. |
| Alarm sounds without smoke | Nuisance alarm (cooking smoke, steam, dust) | Press the Test/Silence button. Ventilate the area. Clean the alarm. |
| L'alarma no sona durant la prova | No power, unit malfunction | Ensure power is on. Check wiring connections. Replace the unit if still unresponsive. |
Per a problemes persistents, contacteu amb l'atenció al client.
8. Especificacions
- Model: 9120LBL
- Font d'alimentació: Hardwired (120V AC) with 10-Year Sealed Lithium Battery Backup
- Tipus de sensor: Ionització
- Volum de l'alarma: 85 dB a 10 peus
- Dimensions del producte: 5.58 "P x 5.58" W x 1.99" H
- Pes de l'article: 0.61 lliures (aproximadament 9.8 unces)
- Color: Blanc
- Material: Plàstic
- Certificat UL: Sí

Image 6: Diagram showing the dimensions of the smoke detector.
9. Garantia
This First Alert BRK 9120LBL smoke detector comes with a limited 10-year warranty. For detailed warranty terms and conditions, please refer to the warranty information provided with your product packaging or visit the official First Alert weblloc.
10. Atenció al client
If you have any questions or require assistance with your First Alert BRK 9120LBL smoke detector, please contact First Alert customer support. Contact information can typically be found on the product packaging or the official First Alert weblloc.





