4 way shut off valves
The 4-way shut-off valves are used on under-the-counter Reverse Osmosis (RO) and Nano Filtration water filtration systems. The 4-way shut-off is responsible for automatically shutting the supply water to the RO system off and on. The 4-way shut-off valve will turn off the water supply (which also stops the drain water), once the storage tank has been filled and the tap is closed. The 4-way shut-off valve is also responsible for turning the water supply back on, this will happen once enough the water level in the tank drops to below a certain level.
If your Reverse Osmosis (RO) system's drain continues to flush water out, even when the tank is full and the tap is closed, it is typically a sign that either the 4-way shut-off valve or the non-return valve elbow, is faulty.
