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Leaking zone valves

Ewan Member Posts: 45
Hoping you can help me...
I have Erie PopTop-series zone valves with 1/2" sweat connections installed on a 4-zone control board. I'm currently pressure testing the board, and have found 2 of the 4 valve bodies are leaking at the bottom of the body (at the interface between the large-hex bottom plug and the main cast body).
I tried carefully tightening the bottom plug on one body and it slowed, but did not stop the leak.

Any suggestions on how to proceed? Should I remove the bottom plug completely, clean, dope and re-install? Have I pooched the bodies while sweating the connections?

Many thanks in advance.


  • JackMack
    JackMack Member Posts: 2
    In Reply

    Certainly, unplugging, dopeing the fitting and re installing is certainly the most inexpesive way to try and fix this problem. If the fitting is rusted or has any type of build up un the threads or if the threads are cross threaded, this may not be your Solution. Replacement may be the answer, but trying to repair it is certainly the first step. Don't forget to purge the system afterwards. Good Luck!
  • JackMack
    JackMack Member Posts: 2

    If you do not know enough about boilers, such as releasing pressure, purging, etc. Please think about calling someone for help. A simple mistake could mean "No Heat" and Frozen Pipes, depending on where you live. I'm not trying to scare you, but what if after you shut down the boiler, you can't get it re lit? Do you know what to do?
  • Air test?

    I was installing a system several years ago, with erie valve. We air tested the system, and it was something like 18 valves out of 20, were leaking from the body. Contacted erie and was told, the valves would not hold more than 10 psi of air pressure. Something with the O rings.
  • Ewan
    Ewan Member Posts: 45
    Thanks JackMack

    for your reply.

    Appreciate your words of caution. Fortunately, the control board (with the leaking zone valves) is on the bench and isn't hooked-up to anything except a bicycle pump :)
  • Ewan
    Ewan Member Posts: 45
    Yep... testing with air


    That's exactly what I'm doing. I had the control board piping charged to 40psi with air, and it's hissing audibly from 2 of the Erie valve bodies and possibly slow leaking out of the other 2.

    Did your valves work okay when the system was filled with water?
  • Kal Row
    Kal Row Member Posts: 1,520
    will only hold water...

    it's like the o-ring on water filter housings - they let the air out and hold the water, dont tighten the plugs too much, loosen and tighten until the water just stops, o-rings hold back pressure as long a the majority of the o-ring is against something solid and only a couple of atoms worth hold back the pressure

    think of o-rings this way
    PerSquareInch with the "square" being the key word - it's exponential - a few atoms worth of a "square", is a tiny fraction of the square, and thus only has to hold a tiny fraction of the PerSquareInch'es of pressure, – if you wrench it down, and you have increased the contact area exponentially, but the strength of the rubber by compression, has only increased linearly (if that much) and is lagging way behind in the required square strength
    Even worse, the deformation of the perfect circular cross section, changes it’s whole strength structure for the worse

    - IT'S NOT A GASKET!!!

    This is a recording… people just don’t get o-rings…
    The Morton Thiokol design engineers that build the solid rocket boosters get it, and they seal the pressure that creates 1.5 million pounds of thrust at the nozzle with a tiny o-rings, but the decision makers before the shuttle disaster - did not listen to the engineers that said that ice formation could compromise the o-rings physical support structure – and the rest is history, the only design change they made afterward is a better caulk to keep water condensation out of the o-ring area and prevent freeze deformation – still using the same o-rings – aint nothing wrong with them
  • Ewan
    Ewan Member Posts: 45
    Terrific Kal...

    ... many thanks for your reply.
    Certainly puts my mind at ease... wasn't too pleased watching air bubbles pour out of the valve bodies.

    Thanks again to all.
  • Ewan
    Ewan Member Posts: 45
    Some closure

    Happy to report that I ditched the bicycle pump in favor of the garden hose and everything's copasetic. I loosened and tightened the bottom plug as Kal suggested and all's good… no leaks.

    Gotta love The Wall! Thanks again.
This discussion has been closed.