Compression Fittings (with string)

Discussion in 'Shop Talk' started by Jennifer L., Dec 31, 2006.

  1. Jennifer L.

    Jennifer L. Well-Known Member Supporter

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    Thanks for all the help everyone has given me so far on the heating cable in pvc line for my rabbit watering. I finally got the system up and running yesterday and it's not too bad. A few of the drinkers leak, but less than I expected, so I'll fix them over time. But the problem I do have is the compression fittings where the heating cables go in and out of the CPVC lines. Some of them leak quite badly.

    These fittings came with small amounts of string to compress and shut off the water. Pieces of string maybe three inches long. I don't know if I put them in wrong or what, but they are not much good. I then took the fittings apart and put in a lot of string, enough so that it was almost hard to start screwing in the top part of the fitting. They still leak. What do you have to do to get these to stop leaking? Is it just a matter of stuffing in more and more string until they quit? I put the string in by winding it loosely around the heating cable, then taking my jack knife and pressing the string in evenly all around. It goes in quite well that way with even coverage. Any suggestions?

    Jennifer
     
  2. moopups

    moopups In Remembrance

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    Can you locate a visual link so we can see what your describing?
     

  3. Jennifer L.

    Jennifer L. Well-Known Member Supporter

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    Can't find my camera to get a picture of one right now, Moopups. I'll see if I can find it later and post one.

    Right now I'm thinking I just have to put more packing in (string) and that should take care of it. There's no reason that I can see for them to continue leaking otherwise, but it's been bugging me!

    Jennifer
     
  4. james dilley

    james dilley Well-Known Member Supporter

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    You might need Silacone rubber around the outside in the worse case. Try looking for What used to be packing compound. It was A thread to rope size material theat was inpregmented with A substance to stop fitting from leaking in boilers if I remember right.
     
  5. Jennifer L.

    Jennifer L. Well-Known Member Supporter

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    Thanks, James. I hadn't thought of silicone. I'll keep that in mind if I need it. It's a warm day today so if I have time I'll try packing them with more string and see if I get closer to having them stop that way. There are 8 fittings in the lines. Two are almost leak free, three drip a bit and since the rabbits are in there "watering" the floor too, it's not too bad, then there are three others that are a good steady drip that's too much.

    Jennifer