( turn the black knob to flow direction to right position) once every 3 to 6 months for 5 minutes, in order to enable the valve Passing fast & high speed flow of water over the membrane surface and clean off any remains or scale that would cause clogging and effects your membrane life.
Recommended for 50 to 75 GPD Reverse Osmosis membranes
It's good to change it in regular schedule to prevent clogging. Mine was dirty but still working.
Reviewed by: Rommel Yanto from Brampton, Canada .