The negative pressure valve causes distortion of the filter column

Why is the Composite filter column distorted?

• The filtration system operates at high pressure, but when it stops or is sucked due to a series pump or back-sucking water, it will create negative pressure, causing the Composite tank to “sink” and causing the filter column to become distorted.
• When negative pressure occurs inside the filter system, especially for FRP composite filter tanks, the tank will dent or bounce up and down many times, cracking the fiberglass layer, causing water leaks.

Operating principle of anti-negative pressure valve

• When the system operates with positive pressure, the valve will close
• When there is suction in the tank, negative pressure will be created (Pump RO suction directly), the valve will open automatically so that the outside air enters to equalize the pressure and the system does not “suck” in. Thanks to that, the system is protected

When is it necessary to install an anti-negative pressure valve?

• When installing the pump suction head directly into the Composite column system
• When using a submersible well pump, the pump stops and water will be drawn back
• When the Composite tank is 2162 inches or larger

Anti-negative pressure valve for Composite filter columns

How to limit the phenomenon of negative pressure causing tank distortion.

• Install an intermediate water tank for the filtration system, avoid pumping water from the composite column
• Install a one-way valve on the pipeline, especially at the pump output before entering the filter tank to prevent water from running back when the system is stopped.
• Install anti-negative pressure valves on the pipes of each filter column

Refer to here