RO Three-Way Shut-Off Valve | 1/4" Quick Connect

A 3-way shut-off / stop valve for RO system service and isolation — the manual valve that lets you turn off the water to your RO system without shutting off the mains, or isolate specific sections of the system for cartridge changes and maintenance.

Why Every RO Install Needs a Shut-Off Valve

Without a dedicated service valve, every RO cartridge change or repair requires shutting off the entire household water supply at the meter or main isolation valve. That's:

• Disruptive to other water-using activities in the house
• Time-consuming to track down the right isolation point
• Risky for inexperienced DIYers who may forget to turn the main back on

A dedicated RO shut-off valve sits inline in the cold-water feed to the RO system — turn it manually, and only the RO system loses supply. Mains supply to the kitchen tap, dishwasher, fridge water line, etc. continues normally.

Three-Way Configuration

The "3-way" designation refers to the three ports:

• 1/4" quick-connect — connects to RO supply tubing
• 1/4" quick-connect — connects to onward RO supply tubing
• 1/2" threaded — typically connects to a needle valve or chrome shut-off knob mounted on a visible service panel

This configuration lets you mount the manual control knob in an accessible location (under-sink front, or service cabinet) while the tube run goes through the back of the cabinet — clean installation, visible control point.

Installation

Quick-connect ends:

1. Cut tube square
2. Push tube fully into each push-fit port
3. Pull gently to confirm

Threaded end:

1. Apply PTFE thread tape (2-3 wraps clockwise)
2. Thread the manual valve handle or knob into the 1/2" port
3. Tighten snug, don't over-torque

Specifications

• Connections: 1/4" QC × 1/4" QC × 1/2" threaded
• Function: manual inline isolation valve
• Application: residential RO supply isolation