The attached photo shows the flow diagram for the APRO5500 membrane.
The new shut-off valve has a different design than the original.
The previous design has the in-and-out on the right side with the plumbing going horizontally. The new design will also have the in-and-out on the right side, but the flow rate goes up and down.
The inlet tube is coming from the right filter and the outlet tube goes to the feed of the membrane. Replace each tube one by one or mark the tube and new valve by #1, #2, #3, #4.
If you have any questions or comments, please let us know!