Program Wheel for Fleck 5600 Econominder Valves, 3/4" standard Label .
0-2,100 gallons.
Old part number 14039.

The entire program wheel should be moving in relationship to the ARROW as your water is used.
Once the ARROW is pointing to ZERO, the unit will regenerate at 2 a.m.

If you are having a problem with the WHITE dot moving from the Number it is set to, then you'll need to replace the program wheel because it is broken.
The clear portion is "locked" into the black portion by 3 small "teeth" that can break.

SEE How To Set Wheel Video

"How to Set Meter without the People or Hardness Labels on Fleck Econominder Valves

NOTE: To replace the Program Wheel, you'll have to remove the Front Knob, and parts underneath it first.
There are 2 ball bearings under the program wheel ( not shown in diagram ), so don't loose them.
Best to remove the power head ( drive assembly ) from the Valve Body, and work on a table with "face" UP.
and see
Exploded Diagram