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Magical mystery fitting

SVDW Member Posts: 80
This is installed on 2” DHW  line in a school built in the 50’s. No rating plate or rivet holes where there ever was one. Anyone have any idea what it might be? My guess so far is a thermosiphon recirc device or an exp compensator. Smartest piping guys in the world are on this forum.  Any of you seen this before? Thank you for your time! 


    JUGHNE Member Posts: 11,060
    edited July 2022

    It would have most likely been plugged by now.

    Maybe the guts are out of it.
  • PC7060
    PC7060 Member Posts: 1,158
    check valve?
    JUGHNEdelta Tmattmia2
  • Larry Weingarten
    Larry Weingarten Member Posts: 3,289
    edited July 2022
    Hi, it could be something unusual like magnetic water treatment… I think the only way to know for sure is to take the unions off, unbolt it and see what’s inside.

    Yours, Larry
  • Big Ed_4
    Big Ed_4 Member Posts: 2,783
    Check Valve upstream from the fire hydrant system ?
    I have enough experience to know , that I dont know it all
    EBEBRATT-Ed Member Posts: 15,517
    Looks like maybe a packing joint on the left side. I would think it is an expansion device
  • PC7060
    PC7060 Member Posts: 1,158
    Open it! Open it!  :D
  • rick in Alaska
    rick in Alaska Member Posts: 1,457
    I'm wondering if it is a flow restrictor? Is the packing gland on the side because it is set up like a dresser coupling for the copper pipe?