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Thumping SRV

Discussion in 'Irrigation' started by londonrain, Sep 30, 2007.

  1. Replace two thumping SRV valves this week on the same job. The PGV tops fit the SRV valve body so it is an easy fix...After thinking about the problem I believe it is the solenoid not opening all the way.

    Pulled out my calipers and measured the solenoid hole on both valve tops. The SRV is 2/100th" smaller than the PGV... Same measurements on a few different valve tops, all the same.


  2. Interesting. Is the thumping starting at shut down?
  3. One was at start up and the other was at shut down....
  4. Mike Leary

    Mike Leary LawnSite Fanatic
    Posts: 21,976

    I've had "thumping" too..always traced to high pressure.
  5. Both valves use the same solenoid, diaphragm and diaphragm ring.....
  6. Wet_Boots

    Wet_Boots LawnSite Fanatic
    Posts: 47,673

    Opening thumping is kind of maddening. Almost like some oscillation or resonance is going on.
  7. PurpHaze

    PurpHaze LawnSite Fanatic
    Posts: 5,496

    I run into "closing thumping" on rare occasions after installing a new valve. After it's been actuated a couple of times and the Flow Control is set where I want it... it goes away.

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