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RTV, Tape, Or Dope?

lee_7 Member Posts: 458
you would not need to get hose in toflush boiler. Attached double ended washer hose and back flush boiler. pretty simple to do. I would rather have a valve to open, then a cap to unscrew. just my opinion.


  • Al Hendrickson_9
    Al Hendrickson_9 Member Posts: 1

    There is a drain fitting on my boiler, actually a short 2" nipple and a cap. Despite using teflon tape and moderate torque when replacing it, it's always a struggle to remove the cap for the annual flushing the next year. this year I used pipe dope, but that might be even worse.

    Is there something I can use to make the job easier? I don't think anti-sieze would be very compatible with a steam boiler. How about next time I use some hi-temp RTV silicone gasket sealer on the threads, tighten it just past hand-tight, and let it set up before refilling?

    Would there be trouble with this?
  • lee_7
    lee_7 Member Posts: 458

    If it is below water line, why not just put in boiler drain valve and be done with it? Just a question.
  • Scalding!

    1) I want to be able to get a hose in through the fitting to wash out the sediment. I guess a full-port ball valve would work for that . . . but . . .

    2) That scares me. If opened while steaming, a valve like that would release a violent gush of scalding water . . . unless I capped it when it was not being used . . .

    3) . . . which brings us back to the original issue . . .

    4) unless I found a steam-rated full-port ball valve with a place for a padlock.

    Does something like this exist?
  • Couderay
    Couderay Member Posts: 314
    Steam rated ball valves

    Apollo makes a steam rated ball valve that is full port and can be had with a locking handle. On the boilers I work on we also put nipple with a cap and I never seize the cap to the nipple. Never been an issue.
  • s. reja
    s. reja Member Posts: 3
    valve above water line

    Is there a problem, other than the issues with mistakenly opening, with having a full port ball valve above the water line, say for skimming purposes. Does it need a special rating - would the steam damage it??
This discussion has been closed.