Leaking elbow connection on hot water cylinder

Discussion in 'Plumbing and Central Heating' started by DJS1, 29 Jan 2010.

  1. DJS1

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    I replaced my vented hot water cylinder last year because the coil was leaking into it. The elbow connector that joined onto the thread of the prefitted coil was vertical when fully tightened on the old cylinder, but on the new cylinder it's a few degrees past the vertical (nearer the 11 o'clock position rather than 12.00) and over time has worked loose and is leaking(I guess its because the existing pipework pulled it back to vertical). Can I put a felt washer on the joint so that's it's tight when vertical and is there any jointing product I can use in case of weeps?

    Thanks in advance for any help.
     
  2. Gasop

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    You will have to remake the joint with PTFE tape or thread sealing string .

    You cannot use a sealing washer on the kind of joint you have on your cylinder.

    Applied correctly there will be no weeps or leaks.
     
  3. Hugh Jaleak

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    You need to redo the joint as described, and then adjust the pipework to fit. Trying to 'force' pipework to fit is asking for trouble IMO.

    I changed a cylinder that had split recently as previous installer had forced return to fit it. The pressure on the primary return tapping has split the cylinder at this point. I cut it off and realigned it to fit correctly.
     
  4. DJS1

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    Thanks for your replies.
    I made the original joint in PTFE, then tried to remake it bulking it out with further PTFE in order to get the joint tight and vertical - which obviously failed in the end. Am I likely to be able to achieve this with the sealing string or am I just going to have to redo the original pipework? If I have to do some pipe bending I will, but I'd rather not have to right now.

    Cheers again
     
  5. lilleville

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    You really need boss white and hemp on cylinder joints, PTFE is too lightweight! You need to re-do the pipework so it sits comfortably. Its no good forcing the pipes, as matey said, you're asking for trouble. Sometimes the only way through it is through it! Sorry!!
    Beware not to crack the weld holding the coil in place by forcing it or over tightening it! Got the tee-shirt for that one!!
     
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  6. kirkgas

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    i thought boss white and hemp was banned years ago on all but heating pipes, loctite 55 is the way forward for this type of joint, you can tighten the fitting then back it off if required to line up with fitting, as others have said best to alter pipework rather than strain the cylinder
     
  7. 1oldspindle

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    Hold it chaps,,,,,,
    Why are any of you struggling with these joints at all.
    If the correct cylinder unions were being used you would not have a target position to have to re-set in the first place.
    Cylinder unions have a tapered fitting on the end that slightly enters the coil tapping then the nut just tightens onto the thread. No jointing compound on the thread at all. ;)
     
  8. 1oldspindle

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    bes.com
    Cylinder unions.
     
  9. Nige F

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    Is the coil not a heating pipe ;) Locktite, schmocktite :rolleyes: .If the OP sends me his address, I`ll post him a lock of hemp in an envelope= OR I could start selling it on eBay :idea:
     

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