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Facility Manager

Message to Mark E. Recommended by Paul P. Mark, last fall we were notified that a problem may exist with the PEX fittings in our building. I understand the issue is caused by an excessive amount of zinc (>15%)in the brass fittings which can lead to dezincification. I received some additional information from Paul stating that we should not be affected by the issue since our hydronic heating loop and domestic hot water loops are completely separate. Our setup consists of two gas boilers with three holding tanks and an expansion tank. The domestic hot water loop is circulated and maintained at 120F. The building was opened for occupancy in 2002. I've attached some photos of the PEX for ID purposes. I was hoping to confirm that our system would not be at risk and that I could find some documentation. Most of the documents I find only state that various conditions that must be present for dezincification (salt/calcium content, water source, high temperatures etc.) If I can confirm the information about a mixed water system it would be a huge relief. Please let me know if I need to provide any further information. Thank you. Scott

Comments

  • No chemist, or metallergist

    Do a search for Thomas water treatment, as they are the boiler water treatment experts.--nbc
  • Mark Eatherton
    Mark Eatherton Member Posts: 5,858
    edited February 2012
    That's not Kitec....

    Kitec had a recall on their PEX-Aluminum-PEX tubing and fittings, and the only failures I am aware of here in Denver had to do with open, potable water systems, not closed loop systems.



    The pipe and fittings shown appear to be Uponor ProPEX fittings. I'd heard that they too had been named over dezincification, but personally have no experience with their potable water brass fittings. Quite honestly, I think EVERY manufacturer who uses brass with zinc is the target of legal action.



    My suggestion woud be to contact Uponor, and ask them for direction and guidance. Try contacting them at 800-321-1439 . Ask for my good friend Ingrid Matson. If she can't answer your question, I am sure she will know who can. Uponor is a VERY responsible company, rest assured.



    EDIT PS: For what its worth, I've not seen ANY cases of dezincification in a tight, closed loop heating system. Only open loop systems.



    ME

    There was an error rendering this rich post.

  • LarryC
    LarryC Member Posts: 331
    DHW temperature setpoint?

    "The domestic hot water loop is circulated and maintained at 120 F." 



    ME, I thought you would have made a comment about the need to maintain the DHW temperature at 140 F?
  • Mark Eatherton
    Mark Eatherton Member Posts: 5,858
    Yeah, I guess I should have, but...

    elevated temperatures enhance dezincification. A fine line to talk and walk.



    Thanks for brining it to light.



    ME

    There was an error rendering this rich post.

This discussion has been closed.