1. Introduction
This manual provides detailed instructions for the installation, operation, and maintenance of your Waterdrop 15UA Under Sink Water Filter System. Please read this manual thoroughly before installation and use to ensure proper function and safety. The Waterdrop 15UA system is designed to provide filtered water directly from your kitchen faucet, reducing various contaminants while retaining beneficial minerals.

Image 1.1: Waterdrop 15UA Under Sink Water Filter System with hoses and connectors.
2. Safety Information
- Connect the system only to a cold water supply.
- Do not install the system in direct sunlight or near heat sources.
- Ensure all connections are secure to prevent leaks.
- The activated carbon filter is made from natural coconut shells. If you have allergies, please confirm suitability.
- Verify the dimensions of your under-sink space before installation to ensure proper fit.
- Do not use with water that is microbiologically unsafe or of unknown quality without adequate disinfection before or after the system.
3. Package Contents
Please check the package to ensure all components are present:
- Waterdrop Undersink Water Filtration System ×1
- Inlet hose ×1
- Outlet hose ×1
- 3/8’’–1/2’’ Convertor set ×1
- Self-tapping screws ×2
- Teflon tape ×1
- Drilling sticker ×1

Image 3.1: Complete accessory kit for the Waterdrop 15UA system, showing all included parts and dimensions.
4. Setup & Installation
The Waterdrop 15UA system is designed for quick and easy installation, typically taking less than 3 minutes. It connects directly to your existing cold water line.
4.1 Pre-Installation Steps
- Ensure you have all components listed in Section 3.
- Turn off the cold water supply to your kitchen faucet.
- Relieve pressure by opening the cold water faucet until water stops flowing.
4.2 Connecting the System
The system features push-to-connect fittings for simplified installation. It includes a 3/8” hose for direct connection to standard 3/8’’ feed water valves. A 3/8’’–1/2’’ convertor fitting is provided for compatibility with both 1/2’’ and 3/8’’ cold water lines.
- Connect the inlet hose to your cold water supply valve.
- Connect the outlet hose to your faucet's cold water line.
- Ensure the filter unit is securely mounted under the sink using the self-tapping screws and drilling sticker if needed.

Image 4.1: Diagram illustrating the innovative design with dual sealing gaskets for secure connections.
4.3 Post-Installation Steps
- Slowly turn on the cold water supply.
- Check all connections for leaks. Tighten if necessary.
- Open the filtered water faucet and flush the filter for 5 minutes to remove any carbon fines and air.

Image 4.2: Visual guide for the 3-second filter replacement and 3-minute installation process.
5. Operating Instructions
Once installed and flushed, your Waterdrop 15UA system is ready for use. It provides a fast and stable flow of filtered water.
5.1 Water Flow and Quality
The system delivers pure and fresh-tasting water with a tested full flow rate of 0.75 gallons per minute (gpm) at 60 psi. The innovative multistage filtration effectively reduces PFAS, PFOA/PFOS, lead, chlorine, heavy metals, chemical impurities, sediment, and other large particles, while retaining essential minerals like calcium, potassium, sodium, and magnesium.

Image 5.1: Demonstrates the steady and fast water supply, filling a cup in approximately 5 seconds.
5.2 Usage Environments
The Waterdrop 15UA is suitable for various applications, including:
- Kitchen: Drinking, cooking, washing produce.
- Bathroom: Skincare, brushing teeth.
- RV: Providing filtered water on the go.
- Office: For daily hydration needs.

Image 5.2: Examples of product usage environments including kitchen, bathroom, and RV.
6. Maintenance
6.1 Filter Replacement
The filter cartridge (Model: WD-RF15) has a maximum service life of 24 months when used with municipal water. Regular replacement ensures optimal filtration performance.
- Turn off the cold water supply to the system.
- Twist the old filter cartridge counter-clockwise to unlock and remove it. The system's design allows for a 3-second replacement process.
- Insert the new filter cartridge and twist clockwise to lock it into place.
- Turn on the cold water supply and flush the new filter for 5 minutes.

Image 6.1: Illustration of the integrated filter design and the twist-free connection for easy replacement.
6.2 Storage During Vacation
If going on vacation, place the filters in separate sealed plastic bags and store them in your refrigerator (not the freezer) to maintain freshness for up to 30 days.
7. Troubleshooting
7.1 Low Water Flow
- Check for Kinks: Ensure hoses are not kinked or bent, which can restrict water flow.
- Filter Clogging: Over time, filters can accumulate particles, reducing flow. The Waterdrop 15UA features an upgraded filtration area with 20X increased dirt adhesion to minimize clogging. If flow remains low, consider replacing the filter.
- Water Pressure: Verify that your household water pressure is adequate. The system operates optimally at 60 psi.
7.2 Water Quality Concerns
- Taste/Odor: If taste or odor issues persist after initial flushing, flush the system for an additional 10-15 minutes. If the problem continues, the filter may need replacement.
- TDS Readings: A TDS (Total Dissolved Solids) meter is not an accurate tool for measuring the effectiveness of this filter. The Waterdrop 15UA system retains beneficial minerals (dissolved solids) like calcium, potassium, sodium, and magnesium, which will still register on a TDS meter. It focuses on removing harmful contaminants, not all dissolved solids.

Image 7.1: Illustrates the contaminants reduced by the filter and clarifies that it does not reduce TDS.
8. Specifications
| Feature | Detail |
|---|---|
| Brand | Waterdrop |
| Model Name | WD-15UA |
| Product Dimensions | 3.9"L x 3.6"W x 16.7"H |
| Item Weight | 1.63 Kilograms (3.59 Pounds) |
| Installation Type | Under Sink |
| Maximum Flow Rate | 0.75 Gallons Per Minute (at 60 psi) |
| Filter Life | Up to 24 months or 16,000 gallons |
| Certifications | IAPMO certified against NSF/ANSI 372 (lead-free) and NSF/ANSI 42 (chlorine, taste, odor reduction). Tested by third-party laboratory against NSF/ANSI 53 (lead reduction). |
| UPC | 840814170847 |

Image 8.1: IAPMO certification document for the Waterdrop 15UA filter system.
9. Warranty and Support
For warranty information, technical assistance, or to purchase replacement filters (Model: WD-RF15), please contact Waterdrop customer support. You can find contact details on the official Waterdrop website or through your retailer.
Replacement filters can be found by searching for "B085G78F7R" on Amazon.







