I am trying to perform the tank sanitizing operation for the reverse osmosis system. One of the procedures involves detaching the tube from the valve, as shown in the first figure. The document does not specify how to do this? Would you like to let me know how to do this? Besides, the second figure shows the tank label and a blue component. I do not know what is that blue component used for? Thanks.
It's a quick connector. Water pressure actually pushes the locking mechanism to hold the tube in.
With the pressure completely relieved you can press the grey ring around the blue tube inward and at the same time pull the tube out.