Fleck 5600 Softener Control Valve with 12 Day Skipper Wheel. 120 volt 60 Hz ( North American standard ) unless you select something different. Simple 12 Day Timer Setting will regeneration when you want it to based on the number of "pins" you slide out. For demand regeneration, see the 5600 Econominder version. Your "backwash" rate ( and injector installed ) is all determined by the Diameter of the RESIN tank the valve is to be used / installed on.Tank Diameter - How To Measure and WhyIf this Valve is to replace an existing Fleck 5600 valve, then the existing By Pass or Piping Yoke will clip on to the valve. * Select "NONE".Otherwise you will NEED to Select with valve order,Either A Yoke - standard Noryl plastic piping connection in either 3/4" or 1" male threads,OR A By-Pass Option can be selected ( again with 3/4" or 1" piping threads to match your plumbing ).NOTE: Valve Cover( for outdoor use ) is an option you may want to order separately if you need one. We include at no extra charge, a new distributor kit. This is part # MD1236. It is a plastic lower screen which can be cemented to a piece of 3/4" PVC pipe to construct a new distributor tube. Your old distributor could be slightly smaller than the ones now used by both Fleck and Autotrol ( old size 13/16", new size 1.05" outer diameter ). We also include a 1.05 Top Distributor Twist On - part # MD1203 at no charge. PLEASE Review these LINKS to additional information about replacing your Valve,
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< Tank Diameter - How To Measure and Why >
< Difference between 12 Day valve and Econominder >
Free Service Manual Download = https://www.nelsencorp.com/customer/docs/SKUDocs/5600_Fleck%20Service%20Manual.pdf