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Automatic Shut Off Valves

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Product Description

Automatic shut off valves (ASOV) stop the flow of concentrate (often referred to as "waste water") when the flow of purified water is stopped (by a float valve, or by other means).  Comes with detailed instructions. Equipped with four quick-connect fittings for instant installation.

ASOV's work only when several other parts are present and working properly:

  1. A float valve or other valve at the end of the purified water output line.  
  2. A check valve (see fittings page) installed between the RO permeate (purified water) port and the auto shut off valve.

When pressure in the purified output tube reaches about 66% of the pressure in the system feedwater tube (standard ASOV), or about 85% in the case of the high pressure ASOV, the device will shut off the flow of feedwater to the RO membrane - and thereby stop the flow of concentrate.  The high pressure ASOV makes sense only in applications where the purified water is being delivered to a pressurized storage container - especially if a permeate pump is also installed.

Alternate part number for the high pressure ASOV: PAMASV

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Product Reviews

  1. ASOV replacement 5 Star Review

    Posted by on 11th Dec 2023

    ASOV was received about 3 days after order. This was for a replacement valve on a RODI system. Installation was easy and the system was returned to normal operation in a few minutes. We always get fast service and quality products from Buckeye Hydro.

  2. New ASOV is perfect 5 Star Review

    Posted by on 23rd Apr 2013

    I installed the valve and it is working like a champ! Thanks so much, I wish I would have called Buckeye first!


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