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If drain flow is clogged or restricted in your water filter, you will need to remove the DLFC ( drain line flow control ) button. This example shows how to remove, clean, and replace the flow button used in the Fleck 5600 Valve.
Our Website: https://www.softenerparts.com/default.asp
DLFC Retainer ( related "buttons" ) =
https://www.softenerparts.com/DLFC_Retainer_Fleck_13173_p/3413173.htm
Tool to remove the DLFC Retainer = https://www.softenerparts.com/TOOL_to_remove_DLFC_Retainer_Fleck_13759_p/3413759.htm