Fleck 5600 & 2510 12 Day Timer Easy Programming Guide
Setting Backwash Frequency:
The 12 day timer comes with all 12 pins pushed inward.
To indicate the days you want to backwash, simply push that particular pin outward from the center.
The industry standard is for every 3 days. That will result in the 1,4,7 and 10 pins being pushed out.
The red arrow indicates what day you are currently on in that 12 day cycle.