Ajax WaterStop

Detecting it isn't enough—you have to cut it off

A leak detector alerts you. But you still need to be there, available, and know where the shut-off valve is located. The Ajax WaterStop shuts off the water supply on its own, in just a few seconds, without any action on your part.

Features

• Automatic Shut-Off Upon Leak Detection
• Manual remote control via the Ajax app
• Three diameters: ½" (DN 15), ¾" (DN 20), and 1" (DN 25)
• Four pre-installed CR123A batteries, up to three years of battery life
• External power supply available at 9–12 V
• Actuator compliant with ISO 5211

Choosing the Right Diameter

The diameter must match that of the pipe on which the valve will be installed. In residential settings, the main water supply line is usually ¾”, though it is sometimes ½” in older systems or apartments. The 1” size is used in large homes and commercial buildings.

If in doubt, note the diameter marked on the existing valve, or ask for advice before ordering: a valve of the wrong size cannot be corrected during installation.

What This Means in Practice

The most costly water damage occurs while you're away—on a weekend, on vacation, or during the workday. That's exactly the kind of situation where an alert on your phone is useless and where a valve that shuts off automatically solves the problem.

What You Need for Automation

Automatic shut-off requires at least one Ajax LeaksProtect sensor on the same system. The valve itself can still be controlled remotely, but it cannot respond to an event it does not detect.