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remodelboy_gw

Shower valve inst-Male Threaded fittings or Unions?

remodelboy
16 years ago

Are using unions a good idea for a shower valve installation?

I normally solder threaded male copper fittings onto short pieces of pipe and then thread them into the shower valve with some pipe thread dope. Then when I do some additional sweating, it seems far enough away so as not to bother the valve or burn the pipe dope.

Occasionally, I notice a pinhole leak at the threads and end up having to redo the run, because I can't tighten the fitting to stop the leak

I just demo'd a shower stall and found that the builder used unions to connect up the shower valve. This seems like a better way to do it. What do you think?

Comments (4)

  • alex5324
    16 years ago

    I have 2 problems...bathtub that won't hold water. It is the type that you do not see the drain...just has the plate with the holes in it...and the mechanism is under that. The problem is...I took the 2 screws off holding the lever...and I can't get that mechanism to come up so I can put a new one in. Is there anything to spray down there to loosen it up? How do I get this out?

    The other problem is that when you try to divert the water from the tub to the shower...,hardly any water comes out of the shower...most still goes into the tub. I went to Home Depot to get a socket wrench so that I could take that old divertor out and there were 3 different sizes at Home Depot...How should I go about replacing this and how do I know what size of a wrench to get or is this best left to a plumber?
    Thank you so much.

    Kathy

  • ron1104
    16 years ago

    BEST LEFT TO A PLUMBER YOU CAN GET YOURSELF INTO A MESS. YOU WILL SPEND MORE MONEY RUNNING BACK AND FORTH TO HOME DEPOT TO GET WRONG PARTS FROM SOME GUY THAT THINKS HE CAN TELL YOU HOW TO DO IT

  • Brewbeer
    16 years ago

    Remodelboy,

    IÂve installed two shower valves on DIY projects. This fist one I did as you have done, i.e., used threaded copper male connectors that had been pre-soldered to lengths of pipe, then screwed them into the valve body, but I used Teflon tape instead of pipe dope, with excellent results (no leaks). The second valve had solder connections. To make this happen, I disassembled the valve, removing all the parts that could get damaged by the heat, did the soldering, then reassembled when the soldering was done.

    Give the Teflon tape method a shot.

  • remodelboy
    Original Author
    16 years ago

    Thanks Brewbeer,

    I've used both techniques that you describe with good results overall.

    I get nervous about soldered connections with some valves as they have soldered connections directly adjacent to where I will solder in the copper lines. I'm pretty good and getting better, but occasionally I will cook an adjacent fitting and it will no longer be water tight.

    With the threaded connection, I have had a very slight leak and have had to redo much of the run because I am worried about cooking the adjacent fittings - you can't just tighten the threaded connection as the rest of the run is soldered.

    When I discovered the connection with unions, I thought that I might be onto something clever - I wanted to get some feedback from several forums. The consensus was, don't mess with the unions - stick with the soldered connections or threaded connections.

    For others viewing this thread, a solution for soldering connections that are close to other soldered connections (that you don't want to cook), take a water soaked rag and tie it around the soldered connection that you don't want to heat up - it will act as a heat sink and help prevent the connection from getting cooked.