We make 2-1/2″ Vanstone flange sensors that are direct replacements for Evapco Cooling tower level controls.  We can use any size vanstone flange to build a sensor into without any issues.  Let us know what you need for your application and we can help you get the right parts.  You can use this sensor appendix to get the correct length sensor tips needed.

Flow Diagram


Flow Diagram

(click image to enlarge)
(right click image to download)

Download Submittal PDF

We use Vanstone flanges whenever it is requested by the customer. It is usually in older existing installations. We use rod extension kits so these rods can be made into any length needed for the application. These allow for the extension and then addition of other extensions to them.

PART NUMBERS for Sensor Tip Extensions

(extensions come with both ends threaded allowing for additional rods to be added as needed)

All Sensor rods are 45.5 inches long.

  • EXT3- Three rods colored Black, White & Red
  • EXT4 – Four rods colored Black, Brown, White, & Red
  • EXT4A – Four rods colored Black, White, Red & Green
  • EXT5- Five rods colored Black, Brown, White, Red & Green
  • EXT6 -Six rods colored Black, Blue, Brown, White, Red & Green

The colors match the colors of the rods in the sensor head and each color corresponds to a specific switch in the controls depending on which one you have.

Each sensor tip comes with the part necessary to assemble them together to the Sensor head.

PROUDLY MADE IN THE U.S.A. blank

All of our liquid level controls and liquid level sensors are assembled right here in the U.S.A.
where we monitor every step of the process.

NOT SURE WHAT YOU NEED? JUST CALL BECAUSE WE’RE HERE TO HELP! 480-905-1892

We offer products comparable to the products offered by the above companies. See our website pages for further information on the products. The tradenames and trademarks in this page are owned by their respective companies or are the same name as the company. They are mentioned for comparison purposes only. They are in no way affiliated with System Dynamics, Inc or WaterLine Controls.