how to sweat a threaded valve?

Discussion in 'Plumbing Forum, Professional & DIY Advice, Tips & ' started by jerome7, Jul 16, 2013.

  1. jerome7

    jerome7 New Member

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    Location:
    95020
    I have a valve w/ threads on the inlet and outlets. Is it preferable to sweat the copper pipe by inserting it inside the in/outlet or use a female adapter and sweat the pipe to it. The attached picture shows both options.

    I believe before sweating we need to remove the cartridge which is usually made of plastic and can melt during sweating. But on this valve, I can see a yellow plastic tip sticking out, but I don't see any way to disassemble the valve. It's a diverter valve (Kenzo from Pfister).

    How can I insert this valve between my shower head and shower supply valve without damaging it.

    Thanks for you help

    Attached Files:

  2. Tom Sawyer

    Tom Sawyer In the Trades

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    Location:
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    In the box that the valve came in you will find the instructions. The valve is designed to use either threaded or swett connections according to the directions.
  3. hj

    hj Moderator & Master Plumber Staff Member

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    Most plumbers would solder in to the valve. Most DIYers would use the adapters. You unscrew the front of the diverter to take it apart.
  4. DougB

    DougB Member

    I'd sweat the FPT adapter to a length of copper tubing - then connect the assembly to the valve.
  5. hj

    hj Moderator & Master Plumber Staff Member

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    Doing that is why most DIYers use the adapters.
  6. jadnashua

    jadnashua Retired Defense Industry Engineer xxx

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    FWIW, it's always a good idea to take the cartridge out and flush the lines before reinstalling it. So, if you have to take it apart anyway, why use the adapters which adds another joint that could leak? Adds cost, too (not much, but hey, it's still money).
  7. Gary Swart

    Gary Swart In the Trades

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    I have not claim on being a pro, and as HJ points out, most of us DIY types solder to the adapter then screw the assembly into the valve. Why? What did you not understand about me not being a pro? LOL Yes, Jim, it does cost a few cents to do that, but I'll spend a few cent on insurance to potentially save dollars on replacing a valve that got too hot. I'd like to think that I have good enough soldering skills to not screw up, but I'm not willing to gamble to find out.
  8. jadnashua

    jadnashua Retired Defense Industry Engineer xxx

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    You missed my point...many installation instructions tell you to remove the cartridge, turn the water on to flush the lines out (prevents clogging up the new cartridge), then reinstall it. So, if you follow instructions, you'd have the cartridge out so why not solder the pipes in then - it's more robust and less prone to problems.
  9. jerome7

    jerome7 New Member

    Messages:
    75
    Location:
    95020
    Thanks for your input all. In my case, if I use an adapter I might have to screw it to the valve first, then sweat the copper pipe to the adapter.
    The reason is the supply valve is already in place and I don't need to move it. Since I can't rotate it, I need to screw the adapter first than slide the pipe in and sweat it.
  10. jadnashua

    jadnashua Retired Defense Industry Engineer xxx

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    Location:
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    Note a great idea...neither the tape nor pipe dope really like the heat of soldering right next to it. Then, once you've got the pipe solid with the soldered connection, if the threaded one does leak, you have to unsolder things and probably cut thing in order to be able to pull it out and fix things.
  11. jerome7

    jerome7 New Member

    Messages:
    75
    Location:
    95020
    I didn't thought about that tape, but that is a good catch. Thanks.
    I see no advantage of using the adapter at this point. More joins is more potential points of failure.
    If I could assemble the whole system on the floor and then attach it to the wall, I can see how the adapter could make it easier..
    But I don't want to disconnect the supply valve from the PEX tubes and have to reattach it later.
  12. Terry

    Terry Administrator Staff Member

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    If you thread the adapter on first before soldering, it's the same as inserting the pipe and soldering.
    Except you have added that many more places to leak.

    If you use a male adapter, you solder it onto a section of pipe first, and then thread to the valve. Which I consider a big waste of time, and potential for plumbing problems.
  13. MACPLUMB 777

    MACPLUMB 777 TROJAN WORLDWIDE SALES RP

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    Aw just get some shark bites and be done with it already
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