First Alert SM210L
First Alert SM210L Smoke Alarm Instruction Manual
Model: SM210L | Brand: First Alert
Introduction
The First Alert SM210L Smoke Alarm provides advanced smoke detection with a 10-year sealed battery and an integrated Safety Path Light. Designed for ease of use and long-term reliability, this alarm helps ensure the safety of your home and family.
Key Features
- 10-Year Sealed Battery: Eliminates the need for battery replacements and annoying low-battery chirps for a full decade.
- Safety Path Light: Illuminates your path to safety in case of an emergency, guiding you through smoke-filled environments.
- Precision Detection Technology: Advanced sensing technology complies with new industry standards, reducing nuisance alarms from cooking while providing early warning of actual fires.
- Slim Profile Design: Half the depth of a standard alarm, allowing for seamless integration into any room's aesthetic.
- Test/Silence Button: Allows for convenient testing of the alarm's functionality and silencing of nuisance alarms.
Setup and Installation
Proper placement and installation are crucial for optimal performance and safety. Install smoke alarms on every level of your home and in every bedroom.
Recommended Placement

This diagram illustrates the recommended placement of smoke alarms, carbon monoxide alarms, and fire extinguishers throughout a typical home, including bedrooms, hallways, living room, kitchen, basement, and garage.
Mounting Instructions
- Prepare the Mounting Bracket: Use the provided screws and anchors to securely attach the mounting bracket to the ceiling or wall. Ensure the screws are firmly in place.
- Activate the Alarm: Align the alarm with the mounting bracket and turn clockwise until it clicks into place. This action activates the sealed battery.
- Test the Alarm: Press and hold the Test/Silence button on the alarm until it sounds. This confirms the alarm is activated and functioning correctly.

The smoke alarm comes with a mounting bracket, screws, and wall anchors for easy installation. The bracket is designed to be securely attached to a ceiling or wall.

The front of the smoke alarm features a prominent Test/Silence button and a power indicator light. Pressing this button tests the alarm's functionality.
Operation
Testing the Alarm
Test your smoke alarm regularly, at least once a month, to ensure it is operating properly. Press and hold the Test/Silence button until the alarm sounds. The alarm will emit a loud, pulsating sound.
Silencing Nuisance Alarms
If the alarm sounds due to non-emergency conditions (e.g., cooking smoke, steam), press the Test/Silence button to temporarily silence it. The alarm will automatically reset after a few minutes if the smoke clears.
Maintenance
The First Alert SM210L features a sealed 10-year battery, eliminating the need for battery replacement. However, regular cleaning and testing are essential.
- Monthly Testing: Test the alarm monthly as described in the "Operation" section.
- Cleaning: Gently vacuum or use clean compressed air to remove accumulated dust from the alarm's vents. Do this monthly or as needed. Avoid using water, cleaners, or solvents, as they may damage the unit.
- End-of-Life Warning: After approximately 10 years, the alarm will begin to chirp three quick chirps every minute, indicating it's time for replacement. This is a permanent signal and the unit must be replaced.

This image emphasizes the importance of replacing smoke alarms at least every 10 years to ensure continued home safety.
Troubleshooting
| Problem | Possible Cause | Solution |
|---|---|---|
| Alarm sounds frequently without apparent smoke. | Nuisance alarms (e.g., cooking smoke, steam), dust accumulation. | Press the Test/Silence button to silence. Relocate the alarm if nuisance alarms persist. Clean the alarm as per maintenance instructions. |
| Alarm chirps three quick chirps every minute. | End-of-life warning. | Replace the alarm immediately. The battery is sealed and cannot be replaced. |
| Alarm does not sound when Test/Silence button is pressed. | Alarm not activated, unit malfunction. | Ensure the alarm is properly aligned and twisted onto the mounting bracket. If still unresponsive, replace the alarm. |
Specifications
- Model: SM210L
- Power Source: 10-Year Sealed Lithium Battery (non-replaceable)
- Sensor Type: Photoelectric
- Alarm Type: Audible
- Dimensions: 1"D x 1"W x 1"H (Slim Profile)
- Weight: 6.24 ounces
- Color: White
- Manufacturer: Resideo
- Certifications: ETL Intertek (Conforms to UL STD 217)
Warranty and Support
For customer service or technical support, please refer to the user's manual included with your product or visit the official First Alert website.
Customer Service Team: 1-800-323-9005
Website: firstalert.com
This product is backed by a 10-year limited warranty, covering defects in material and workmanship from the date of purchase. Please retain your proof of purchase for warranty claims.
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