Fleck Valves - LEAKS out the DRAIN HOSE
LEAKS out the DRAIN HOSE:
Fleck valves use pistons and internal seals to control water flow through the control valve head. When water continuously flows out the drain hose, and the unit has finished the regeneration process ( IN SERVICE position ),
it is usually a "bad" or "worn" SEAL, and replacing the Seals & Spacers is required.
It is also normal to change the Main Piston at the same time,
as age will effect this part over the years,
and as long as you have the valve apart,
it makes sense to put a new piston in at the same time.
Fleck 5000, 5600, 6600, 6700, and our Hankscraft valves all use Seals & Spacers 60125,
but the Main Piston can vary ( 60115-00 for 5000, or one of the 60102-xx for 5600 type valve bodies ).
Reference the different Pistons,
Mechanical ( 60102-00, 60102-10, 60102-20 )
Electronic ( 60102-71, 60102-62 )
5000 Proflo ( also newer Rainsoft models ) 60115-00
Fleck 1500, 2500, 2510 uses Seals & Spacers kit 60121, and standard Piston is 60090.

** Also see below, Reasons why valve is still leaking after replacing 60121 set.
***** Same principles of Leaking Caused by Worn Out or Damaged Seals ( and sometimes a worn or damaged Main Piston ),
applies to the larger Fleck Valves also ( 2750, 2850, 2900, 3150, 3900, 9000, 9100, 9500, etc ).
*** Also, the Fleck 5600 and 2500 parts cross reference to MANY "Brands" out there.... such as MacClean, CUNO, and others.
Reference ID Your Valve Brand