Product Overview
Image 1.1: The RKIN U1 Hot & Cold Alkaline Countertop Reverse Osmosis Water Filter System. This image displays the main unit with its digital display, water dispenser, and a glass of water, alongside the product packaging and filter cartridges.
1. Introduction
This manual provides comprehensive instructions for the RKIN U1 Hot & Cold Alkaline Countertop Reverse Osmosis Water Filter System. The U1 system is designed to provide purified water with multiple temperature options and enhanced properties, including alkaline and hydrogen enrichment. It features a 4-in-1 functionality, offering instant hot, cold, alkaline, and hydrogen-enriched water. The system incorporates advanced reverse osmosis filtration to remove contaminants and includes a built-in TDS monitor and filter lifespan indicator for convenient maintenance.
2. Important Safety Information
Please read all safety instructions carefully before operating the RKIN U1 system. Failure to follow these instructions may result in electric shock, fire, or injury.
- Ensure the appliance is connected to a grounded 100V-120V electrical outlet only. Do not use with 220V outlets without a compatible 1500W continuous power voltage converter.
- Do not immerse the appliance, cord, or plug in water or other liquids.
- Keep the appliance out of reach of children. The hot water function can dispense water at high temperatures; use the child lock feature to prevent accidental burns.
- Do not operate the appliance if the power cord or plug is damaged, or if the appliance malfunctions or has been damaged in any manner.
- Place the appliance on a stable, level surface, away from direct sunlight and heat sources.
- Only use RKIN proprietary filters designed for this system.
- The wastewater produced by the system contains impurities and is not recommended for consumption. It can be used for non-potable purposes like watering plants.
3. What's in the Box
Verify that all components are present upon unpacking your RKIN U1 system:
Image 3.1: Contents of the RKIN U1 packaging. This image displays the main U1 water system unit, three pre-installed filters, a user manual, a laminated guide, a metal clamp, a filter tool, a drip tray, and a cooler plug, all packaged within a cardboard box.
- RKIN U1 Water System Unit
- Pre-Installed Filters (Sediment, Activated Carbon, RO Membrane, Alkaline Post-Filter)
- Polishing Alkaline Post-Filter (additional, if not pre-installed)
- Removable Magnetic Water Drip Tray
- User Manual
- Laminated Guide
- Metal Clamp
- Filter Tool
- Cooler Plug
4. Setup
The RKIN U1 system requires no complex installation. It is designed for countertop use.
- Unpacking: Carefully remove the U1 system and all accessories from the packaging. Place the unit on a stable, level countertop.
- Power Connection: Plug the power cord into a standard 100V-120V grounded electrical outlet.
- Fill Water Tank: Remove the water tank from the back of the unit. Fill it with tap water up to the MAX fill line. Reinsert the tank securely.
Image 4.1: Filling and removing the water tank. The left image shows a person filling the removable water tank with tap water. The right image shows a hand lifting the water tank from the back of the U1 unit.
- Initial Rinse Cycle: Before first use, perform a rinse cycle to flush the filters. Refer to the "Rinse" button on the control panel. This process helps remove any manufacturing residues and prepares the filters for optimal performance. Repeat if water tastes bitter initially.
- Filter Installation: The filters are typically pre-installed. If not, refer to the "Maintenance" section for filter installation instructions.
5. Operation
The RKIN U1 features an intuitive touch control panel for all functions.
Image 5.1: RKIN U1 Smart Touch Control Panel. This image illustrates the various buttons and indicators on the U1's control panel, including options for water temperature, volume, filter life, TDS, hydrogen function, and child lock.
5.1. Control Panel Overview
- Power: Turns the unit on/off.
- Reset: Resets filter life indicators after filter replacement.
- Water Temperature Selection: Buttons for Cold, Milk (warm), Coffee (hot), Tea (very hot), and Hot (customizable).
- Water Volume Selection: Buttons for Small Cup, Big Cup, and customizable volume.
- Rinse: Initiates a rinse cycle for the system.
- Lock: Activates/deactivates the child lock feature, especially important for hot water dispensing.
- Hydrogen (H2): Toggles hydrogen enrichment on or off.
- TDS Display: Shows the Total Dissolved Solids level of the purified water.
- Filter Life Indicator: Displays the remaining lifespan of each filter.
5.2. Dispensing Water
- Select Temperature: Choose your desired water temperature (Cold, Milk, Coffee, Tea, Hot). For customizable hot water, select "Hot" and adjust the temperature using the +/- buttons.
- Select Volume: Choose a preset volume (Small Cup, Big Cup) or adjust the volume using the +/- buttons for a custom dispense.
- Dispense: Place your cup on the drip tray and press the dispense button. The system will automatically stop when the selected volume is reached.
Image 5.2: Dispensing water. This image shows a user dispensing water into a glass from the RKIN U1 system.
5.3. Hydrogen Enrichment
To activate or deactivate the hydrogen enrichment function, press the "H2" button on the control panel. When active, the system will produce hydrogen-enriched water with negative ORP properties.
5.4. Cold Water Cooler Control
To turn the cold water cooler off for energy-saving purposes, press and hold the "Cold" water button for 5 seconds. Repeat this action to turn the cooler back on.
6. Maintenance
Regular maintenance ensures optimal performance and longevity of your RKIN U1 system.
6.1. Filter Replacement
The U1 system features a filter life indicator on the control panel. Replace filters according to the recommended schedule or when indicated by the system.
Image 6.1: U1's Advanced Filter System. This diagram illustrates the five stages of filtration: Sediment filter, Activated carbon filter, Reverse osmosis membrane filter, Alkaline post-filter, and Hydrogen infusion.
- Pre-filter and AlcaPure Post-filter: Replace every 12 months.
- Hydrogen PEM Module: Replace every 6-12 months, depending on usage. A specific tool (sold separately) may be required for replacement.
- Reverse Osmosis Membrane: Replace every 2-4 years, depending on water quality and usage.
RKIN uses proprietary filters designed for easy, leak-free replacement with a quarter-turn mechanism. Replacement filters and modules are available for purchase on Amazon.
Image 6.2: RKIN U1 Filter Cartridges. These images show the design of the RKIN proprietary filter cartridges used in the U1 system.
After replacing any filter, perform a rinse cycle as described in the "Setup" section and reset the filter life indicator on the control panel.
6.2. Drip Tray Cleaning
Regularly empty and clean the removable magnetic drip tray to prevent water overflow and maintain hygiene.
6.3. Wastewater Management
The U1 system produces wastewater containing concentrated impurities. This wastewater is collected in a separate section of the supply tank and is not reused for pure water production. It is not suitable for consumption but can be used for purposes such as watering plants.
7. Troubleshooting
Refer to this section for common issues and their potential solutions. If the problem persists, contact RKIN customer support.
| Problem | Possible Cause | Solution |
|---|---|---|
| No water filtering / "U1 not filtering" / "no water" | Water tank not detected, airlock in system, clogged filters, E1 error. |
|
| Water tastes bitter | New filters, insufficient initial rinse. | Perform additional rinse cycles. The taste should improve after a few cycles. |
| Leaking water from inside | Internal line damage, loose connections. | Immediately unplug the unit. Do not attempt to disassemble. Contact RKIN customer support for assistance. |
| Slow flow rate | Clogged filters, low water pressure in tank. | Check filter life indicators and replace if necessary. Ensure the water tank is adequately filled. |
8. Specifications
| Feature | Detail |
|---|---|
| Model Name | U1 (RKIN-U1) |
| Product Dimensions (L x W x H) | 19" x 9.5" x 17" |
| Weight | Approximately 24 Pounds |
| Installation Type | Countertop (No installation required) |
| Power Requirements | 100V-120V (USA, Canada, Mexico, Japan compatible) |
| Supported Water TDS Level Maximum | 800 PPM |
| Pure Water to Wastewater Ratio | 1:1 (0.5 gallon pure water per 0.5 gallon wastewater from 1 gallon input) |
| Cold Water Cooling Time | Approximately 15 minutes to cool 15 ounces of water to 59°F (15°C) |
| Hot Water Technology | Instant-hot, up to 0.5 gallon maximum volume |
| Hydrogen-Enriched Water ORP | Average -330 to -347 mV (individual results may vary) |
| Filtration Stages | 5-stage (Sediment, Activated Carbon, RO Membrane, Alkaline Post-Filter, Hydrogen Infusion) |
| UPC | 850023391360 |
9. Warranty and Support
For warranty details, please refer to the documentation included with your purchase or visit the official RKIN website. The warranty period typically covers manufacturing defects for a specified duration from the date of purchase.
If you encounter any issues or require technical assistance, please contact RKIN customer support. Many users have reported positive experiences with RKIN's customer service team for troubleshooting and guidance.
Contact Information: Refer to your product packaging or the RKIN official website for the most current customer support contact details.
10. Product Videos
No official product videos from the seller were provided in the product data for embedding in this manual.
