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Gate valve vs. ball valve or other valve type thoughts for skim port & blow-down valves?

We noticed our black iron skim port plug was difficult to tighten sometimes, so we replaced the iron plug with a brass one last year, then saw it occasionally still drips even though easier to tighten now. Would replacing the brass gate valve behind the brass plug in the photo with a brass ball valve or other type of valve be better in the long run to reduce leaks? Also for the 2 lower blow-down valves at each side of the boiler? One of the lower blow-down gate valves per the photo leaks a little unless we back it off a half-turn from tightly closed, hence our thoughts about replacing it with something else. Any reccomendations?


  • ratio
    ratio Member Posts: 3,503
    Put a little pipe dope or Teflon tape on the plug.
  • Jamie Hall
    Jamie Hall Member Posts: 21,535
    Gate valves can be problematic... goop gets caught in the bottom of the seat and prevent them from moving that last little bit. But if you can get them to close, I guess it ranks as if it ain't broke...
    Br. Jamie, osb
    Building superintendent/caretaker, 7200 sq. ft. historic house museum with dependencies in New England
    JUGHNE Member Posts: 10,790
    For the skim port why not get rid of the valve altogether? Just put a pipe coming out (long enough to have the skim dribble not hit the boiler or controls) then a 90, a drop pipe and an iron cap. When you skim you want the port fully open to allow the small stream to float off top oils.
    When done just put the cap back on.

    For the smaller "blow down" valves (boiler drains?), I would replace them with full port 3/4" ball valves with hose adaptor.
  • GW
    GW Member Posts: 4,609
    I was skimming a new boiler today, I’m not leaving that hardware behind. I took the long nipple out and put the plug back in. Little bit of Teflon tape, channel locks.
    Gary Wilson
    Wilson Services, Inc
    Northampton, MA
    [email protected]
    EBEBRATT-Ed Member Posts: 13,790
    Any more pics @GW ?


    Skim ports are seldom used, put some tape and dope on that plug and tighten it....doesn't look like it's made in.

    In the future on steam it's better to "Plug" things with a nipple and a cap......better chance of getting 1 of 2 threads apart than 1 of 1

    For the other drain valves with hose ends:

    But a hose cap and put it on...no more leak

    or buy ball valves but don't buy hose end ball valves (they cost a fortune) buy threaded ball valves and separate hose adapters
  • GW
    GW Member Posts: 4,609
    Ed I forgot to take pix of the system at the end

    small nozzle in a 3 section, 2 1/2” riser / header  

    Gary Wilson
    Wilson Services, Inc
    Northampton, MA
    [email protected]
    EBEBRATT-Ed Member Posts: 13,790
    Those American Stds were good boilers my nephew still has one
  • jhewings
    jhewings Member Posts: 139
    I replaced an American Standard I believe was about 50 years old. Not sure how long steam was going up the chimney lol.
  • cubicacres
    cubicacres Member Posts: 358
    Thanks for the suggestions. We also use the skim port to add 1 steamaster tablet 1-2 times per heating season or before filling it up & running it to 180F to remove most of the oxygen for summer shut-down. If we made a 90 & ran it further down near the floor, we'd need to find another place to add the steamaster tablet. Any other suggestions if we went that route?