Introduction
Thank you for choosing the Sunlite FDL28 Fluorescent Quad Tube Plug-in Bulb. This 28-watt bulb is designed to provide bright, energy-efficient, and long-lasting illumination for various indoor applications. Featuring a GX32D-3 base and a 5000K daylight color temperature, it delivers 1350 lumens of light with an impressive 10,000-hour lifespan. This manual provides essential information for safe installation, operation, and maintenance of your new bulb.

Image: Sunlite FDL28 Fluorescent Quad Tube Plug-in Bulb, showcasing its compact design.
Safety Information
Please read and understand all safety instructions before installing or using this product. Failure to follow these instructions may result in electric shock, fire, or other hazards.
- Turn off power: Always disconnect power to the fixture at the circuit breaker or fuse box before installation, removal, or inspection.
- Handle with care: Fluorescent bulbs contain a small amount of mercury. Handle with care to avoid breakage. In case of breakage, follow local guidelines for cleanup and disposal.
- Indoor use only: This bulb is designed for indoor use in appropriate fixtures. Do not expose to water or excessive moisture.
- Proper base type: Ensure your fixture is compatible with a GX32D-3 base. Forcing an incompatible bulb may damage the fixture or bulb.
- Do not dim: This fluorescent bulb is not designed for use with dimmer switches unless explicitly stated on the packaging or bulb itself. Using it with an incompatible dimmer may cause damage or reduce lifespan.
Setup and Installation
Follow these steps to safely install your Sunlite FDL28 bulb:
- Ensure Power is Off: Before beginning, confirm that the power supply to the light fixture is completely turned off at the circuit breaker or wall switch.
- Remove Old Bulb (if applicable): If replacing an existing bulb, carefully remove it from the fixture. Allow it to cool if it was recently in use.
- Identify Base Type: Verify that your fixture requires a GX32D-3 base. The Sunlite FDL28 bulb has a GX32D-3 plug-in base.
- Insert New Bulb: Align the pins of the GX32D-3 base on the Sunlite FDL28 bulb with the corresponding slots in the fixture's socket. Gently push the bulb into the socket until it is firmly seated. Do not force the bulb.
- Secure Bulb: Ensure the bulb is securely in place and does not wobble.
- Restore Power: Once the bulb is securely installed, restore power to the fixture at the circuit breaker or wall switch.
- Test: Turn on the light switch to confirm the bulb is working correctly.

Image: Close-up view of the GX32D-3 plug-in base, showing the pin configuration.

Image: The Sunlite FDL28 quad tube bulb, illustrating its form factor.
Operating Instructions
Operating the Sunlite FDL28 bulb is straightforward:
- Ensure the bulb is correctly installed in a compatible fixture.
- Turn on the wall switch or fixture switch to illuminate the bulb.
- Turn off the switch to extinguish the bulb.
The bulb will provide 1350 lumens of 5000K daylight illumination, suitable for various indoor environments such as kitchens, offices, or general living spaces.

Image: Example of the Sunlite FDL28 bulb installed in a fluorescent ceiling fixture, providing bright illumination.
Maintenance
Proper care ensures the longevity and performance of your bulb.
- Cleaning: Before cleaning, always turn off the power and allow the bulb to cool. Wipe the bulb gently with a soft, dry cloth. Do not use liquid cleaners or abrasive materials, as these can damage the bulb's surface or internal components.
- Replacement: When the bulb reaches the end of its lifespan (approximately 10,000 hours) or fails, replace it with a new Sunlite FDL28 Fluorescent Quad Tube Plug-in Bulb. Follow the installation steps outlined in this manual.
- Disposal: Fluorescent bulbs contain small amounts of mercury and should be disposed of according to local, state, and federal regulations. Many retailers and municipalities offer recycling programs for fluorescent bulbs.
Troubleshooting
If you encounter issues with your Sunlite FDL28 bulb, refer to the following table:
| Problem | Possible Cause | Solution |
|---|---|---|
| Bulb does not light up. | No power to the fixture. Bulb not properly seated. Defective bulb. Fixture issue. | Check circuit breaker/fuse. Ensure bulb is firmly inserted. Replace bulb with a new one. Consult an electrician if fixture is faulty. |
| Bulb flickers. | Loose connection. End of bulb life. Incompatible dimmer. | Ensure bulb is firmly seated. Replace bulb. Remove dimmer or replace with a compatible fixture. |
| Light output is dim. | Dust or dirt on bulb/fixture. Aging bulb. | Clean bulb and fixture. Replace bulb. |
Specifications
Key technical specifications for the Sunlite FDL28 Fluorescent Quad Tube Plug-in Bulb:
| Feature | Specification |
|---|---|
| Model Number | FDL28/50K |
| Wattage | 28 Watts |
| Light Output | 1350 Lumens |
| Color Temperature | 5000 Kelvin (Daylight) |
| Base Type | GX32D-3 |
| Lifespan | 10,000 Hours |
| Voltage | 120 Volts |
| Color Rendering Index (CRI) | 80 |
| Light Type | Fluorescent (CFL) |
| Indoor/Outdoor Use | Indoor |
| Item Weight | 3.2 ounces |
| Material | Glass, Metal, Plastic |

Image: Diagram highlighting key features including 80 CRI, 10,000-hour lifespan, 5000K Daylight, and energy efficiency.
Warranty and Customer Support
For warranty information, please refer to the product packaging. Sunlite products are designed for quality and reliability.
For further assistance or inquiries, please visit the official Sunlite Store or contact their customer support channels as indicated on the product packaging or their website.
You can find more information about Sunlite products at the Sunlite Store on Amazon.