How to Set a Culligan Mark 100

Published: Apr 18, 2010
Updated: Nov 20, 2021
2 minute read

While there are many settings accessible through the keypad, several have no current function, or aren't adjustable. Once your choices are made, you don't need to reset the Mark 100 unless your needs change.

  1. Find the "Status Button" on the Culligan AccuSoft circuit board. Pressing the button twice shows the "Time-of-Day" adjustment and the number "1" will appear below the time.

  2. Press the "Status Button" again and the "Time of Regeneration" will appear. Pressing the button again takes you to a setting that is unused. Pressing the "Status Button" once more displays the "Salt Dosage," that can be adjusted from three to 15 pounds for nine-inch models and five to 24 pounds on 12-inch models.

  3. Set the "Backwash Time" by pressing the "Status Button" again. The settings can be adjusted by pressing an arrow to range between 37 and 85 minutes for nine-inch units, and 35 to 89 minutes for 12-inch units. Another press of the "Status Button" lets you adjust the hardness level, which ranges between two and 99 parts per gallon.

  4. Use the "Status Button" one more time to select whether or not you want to enable or disable the screen blanking: If you want the display lit continuously, press the "Up" arrow, and the letter "D" will appear. If you press the "Up" arrow again, the "D" will disappear, an "E" will appear, meaning that screen blanking is "Enabled." Press the "Status Button" once more to exit "Set Up."

The Drip Cap

  • If you have a Culligan Mark 100 water softener, you can set the proper operating, regeneration and backwash times based on your needs.
  • Once your choices are made, you don't need to reset the Mark 100 unless your needs change.
  • Pressing the "Status Button" once more displays the "Salt Dosage," that can be adjusted from three to 15 pounds for nine-inch models and five to 24 pounds on 12-inch models.
  • Set the "Backwash Time" by pressing the "Status Button" again.
Will Charpentier

Will Charpentier is a writer who specializes in boating and maritime subjects. A retired ship captain, Charpentier holds a doctorate in applied ocean science and engineering. He is also a certified marine technician and the author of a…

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