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King Valves on Steam Mains

I am planning to install a full port gate valve on a 2" steam main as it comes out of the header, to make it easier to blow out the boiler later on.
I would like to install it on a vertical section of the pipe, but due to the lack of vertical space I am considering to install it on a horizontally sloped line as soon as it turns from the vertical.
Do you see any issues with this valve being there ?

Comments

  • Jamie Hall
    Jamie Hall Member Posts: 23,160
    I would use a full port ball valve, not a gate valve. But otherwise, no -- just make sure that it's fully open most of the time!
    Br. Jamie, osb
    Building superintendent/caretaker, 7200 sq. ft. historic house museum with dependencies in New England
    mboksz
  • mboksz
    mboksz Member Posts: 10
    Thanks - Just wonder why would you prefer ball valves there ?
  • Hap_Hazzard
    Hap_Hazzard Member Posts: 2,846
    I like ball valves better because they are quicker to open and close, less likely to fail, and you can tell at a glance if they’re open or closed. You just need king valves to be open or closed, never in between. 
    Just another DIYer | King of Prussia, PA
    1983(?) Peerless G-561-W-S | 3" drop header, CG400-1090, VXT-24
    mboksz
  • mboksz
    mboksz Member Posts: 10
    Make sense - thanks
  • JohnNY
    JohnNY Member Posts: 3,226
    I would use a gate valve for its shorter length and install it on a vertical pipe either before or after the header.
    Contact John "JohnNY" Cataneo, NYC Master Plumber, Lic 1784
    Consulting & Troubleshooting
    Heating in NYC or NJ.
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  • mboksz
    mboksz Member Posts: 10
    I have quite long risers, but very limited vertical pipe above the header going to the main.
    So for the king valve my choices would be to put them on the risers (I am not sure if that would be OK) or on a horizontal pipe of the mains after the header.
    If I put them on horizontal (slightly sloped) pipes - my only concern would be that small amount of condensate that could possibly be sitting there in the body of the valve. I wonder if that small amount of condensate would cause any issues.
  • EdTheHeaterMan
    EdTheHeaterMan Member Posts: 7,713
    edited September 2022
    I have always preferred King Valves over Queen Valves. Now the the new Monarch, after over 70 years... will be a King, this may get much easier!
    Edward F Young. Retired HVAC ContractorSpecialized in Residential Oil Burner and Hydronics
  • Hap_Hazzard
    Hap_Hazzard Member Posts: 2,846
    JohnNY said:
    I would use a gate valve for its shorter length and install it on a vertical pipe either before or after the header.
    If you install king valves before the header, wouldn’t you also need to put a valve on the equalizer to keep the pressure from pushing water into the header?
    Just another DIYer | King of Prussia, PA
    1983(?) Peerless G-561-W-S | 3" drop header, CG400-1090, VXT-24
  • ChrisJ
    ChrisJ Member Posts: 15,583


    JohnNY said:

    I would use a gate valve for its shorter length and install it on a vertical pipe either before or after the header.

    If you install king valves before the header, wouldn’t you also need to put a valve on the equalizer to keep the pressure from pushing water into the header?


    This is what I keep thinking but I thought maybe I was over complicating things.
    Single pipe quasi-vapor system. Typical operating pressure 0.14 - 0.43 oz. EcoSteam ES-20 Advanced Control for Residential Steam boilers. Rectorseal Steamaster water treatment
  • Jamie Hall
    Jamie Hall Member Posts: 23,160
    ChrisJ said:


    JohnNY said:

    I would use a gate valve for its shorter length and install it on a vertical pipe either before or after the header.

    If you install king valves before the header, wouldn’t you also need to put a valve on the equalizer to keep the pressure from pushing water into the header?

    This is what I keep thinking but I thought maybe I was over complicating things.

    You're not. Yes, you do have to have a valve on the equalizer, if the king valves are on the risers. And make jolly sure that they are both (or all) either closed or open before you start firing things up...
    Br. Jamie, osb
    Building superintendent/caretaker, 7200 sq. ft. historic house museum with dependencies in New England
    Hap_Hazzard