1. Product Overview
The Waterdrop WF13 is a high-performance under sink replacement water filter designed for compatible Waterdrop stainless-steel under sink water filter systems (models WD-AS13, WD-BS13, WD-AP13). This filter is engineered to provide clean, fresh-tasting water by reducing various contaminants while retaining beneficial minerals.
Key Features:
- NSF/ANSI Certified: Certified to NSF/ANSI 42 for chlorine, taste, and odor reduction, and NSF/ANSI 372 for lead-free materials. Reduces PFOA/PFOS and PFAS.
- 6-Stage Advanced Filtration: Utilizes a multi-stage filtration technology to remove harmful substances and enhance water quality.
- Long-lasting Service Life: Provides up to 12 months or 16,000 gallons of filtered water, reducing the frequency of replacements.
- Eco-friendly Design: Helps reduce plastic waste by replacing numerous plastic water bottles.
- Mineral Retention: Designed to retain essential minerals, which contributes to healthy hydration. Note: This system does not lower TDS value as it adds beneficial minerals.
2. Parts List
Ensure all components are present before beginning installation.
- Waterdrop WF13 Replacement Filter Cartridge
- Filter Housing (part of the existing system)
- Inlet Hose
- Outlet Hose
- Wrench Tool (for housing)
- Teflon Tape
- Various Adapters/Connectors (3/8"-1/2" converter, quick-connect lock clips)

Image: Waterdrop WF13 filter and associated system components, including hoses and connectors.
3. Installation Guide
This section provides general installation steps. Refer to your specific system's manual for detailed diagrams and safety precautions. Ensure the main water supply is turned off before starting installation.
Step-by-Step Installation:
- Prepare the Area: Clear the space under your sink. Ensure you have a towel or small bucket to catch any residual water.
- Turn Off Water Supply: Locate the cold water supply valve under your sink and turn it off. Open your kitchen faucet to release any remaining water pressure.
- Connect Inlet Hose: Connect the inlet hose to the cold water supply valve. Use the provided converter (3/8"-1/2") if your valve outlet is 1/2". Apply Teflon tape to external threads for a secure, leak-free connection.
- Connect Outlet Hose: Connect the outlet hose to your faucet's cold water line. Use the appropriate converter if needed.
- Connect Hoses to Filter Head: Connect the inlet hose to the 'IN' port and the outlet hose to the 'OUT' port on the filter head. Ensure hoses are fully inserted into the quick-connect fittings.
- Secure Connections: Once hoses are fully inserted, place the blue lock clips on the fittings to prevent accidental disconnection.
- Mount the Filter System: Secure the filter system in a convenient location under the sink using the provided mounting brackets or by placing it on a flat surface.
- Start the Filter Life Timer (if applicable): If your system includes a filter life timer, press and hold the button for 5 seconds to activate it.
- Check for Leaks and Flush: Slowly turn on the cold water supply. Check all connections for leaks. If leaks occur, turn off the water, re-tighten connections, and re-apply Teflon tape if necessary. Flush the filter by running cold water through the faucet for 5 minutes to remove carbon fines and air.
Video: Installation guide for Waterdrop WD-AS13 under sink water filter system. This video demonstrates the connection process for the inlet and outlet hoses, and flushing the system.
4. Operating Instructions
Once installed and flushed, your Waterdrop WF13 filter system is ready for use. Simply turn on your cold water faucet to enjoy filtered water. The system operates automatically, providing filtered water on demand.
Important Notes:
- Use only with cold water. Do not connect to a hot water supply.
- The system does not reduce Total Dissolved Solids (TDS) as it is designed to retain beneficial minerals.
- For optimal performance, ensure the filter is flushed for 5 minutes after any replacement.
5. Maintenance and Filter Replacement
Regular filter replacement is crucial for maintaining optimal water quality and system performance. The WF13 filter has a lifespan of 12 months or 16,000 gallons, whichever comes first.
Filter Replacement Steps:
- Turn Off Water Supply: Turn off the cold water supply valve under the sink and open the faucet to release pressure.
- Unscrew Housing: Use the provided wrench tool to unscrew the filter housing. Be prepared for a small amount of water to overflow; place a towel or container underneath.
- Remove Old Filter: Pull out the old filter cartridge from the housing.
- Insert New Filter: Remove the protective cap from the new Waterdrop WF13 filter. Insert the new filter cartridge into the designated slot in the housing, pushing gently until it reaches the final position.
- Tighten Housing: Screw the housing back into place and tighten it securely with the wrench tool. Do not overtighten.
- Reset Filter Life Timer (if applicable): If your system has a timer, short press the button to arouse the light, then hold press for 5 seconds until the system buzzes 3 times to reset the timer.
- Turn On Water and Flush: Slowly turn on the cold water supply. Check for leaks. Flush the new filter by running cold water through the faucet for 5 minutes.
Video: Filter replacement guide for Waterdrop UL12A under sink water filter system. This video demonstrates the steps for replacing the filter cartridge and resetting the timer.
6. Troubleshooting
- Reduced Water Flow: This may indicate that the filter is nearing the end of its lifespan and needs replacement. Ensure the water supply valve is fully open.
- Leaks: Turn off the water supply immediately. Check all connections for proper tightening. Ensure Teflon tape is correctly applied to threaded connections. Verify that the filter cartridge is seated correctly within the housing.
- Unpleasant Taste/Odor: If taste or odor returns, the filter may be exhausted and requires replacement. Ensure the filter was properly flushed after installation.
- Cloudy Water After Replacement: This is usually carbon fines from the new filter. Flush the filter for an extended period (5-10 minutes) until the water runs clear.
7. Specifications
| Material | Stainless Steel |
| Product Dimensions | 2.87"D x 2.87"W x 10.39"H |
| External Testing Certification | ANSI, NSF |
| Product Benefits | Removes chlorine, lead, PFOA/PFOS, and PFAS; adds essential minerals for improved taste and health; long-lasting service life; eco-friendly by reducing plastic waste |
| Item Weight | 11.6 ounces |
| Compatible Water Purifier Models | Waterdrop WD-AS13, WD-BS13, WD-AP13 |
8. Warranty and Support
For warranty information, technical support, or to purchase replacement filters, please visit the official Waterdrop website or contact their customer service. Keep your purchase receipt for warranty claims.
Contact Information:
- Website: www.waterdropfilter.com
- Customer Service: Refer to your product packaging or Waterdrop's website for the most current contact details.





