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Drop Header???

After lots of time researching how these steam boilers are supposed to be piped, I think I have gained the knowledge required to replace my very wrong near boiler piping. My main question is whether I should go with a drop header or the standard set up that the manufacturer shows. I have quite a bit of head room to come off the top of the boiler. This is a Weil McClain EGH-95 series 4. It is in a commercial building. The certified "Expert" (or knucklehead) that installed it completely ignored the manufacturers instructions and installed no equalizer or Hartford loop. This was installed 5 years ago, before I worked here. Where the boiler connects to the system, the connection size is 5" pipe. Would it be a good idea to go with a 5" header and riser to the system. I figured it would help slow the steam. Any other advice or suggestions would be greatly appreciated, I will be starting this project in the next couple weeks to get ready for winter. We are currently making very wet steam. Also what is the preferred method of boiler cleaning among everyone here. I want to make sure we're in good shape. Here are some pictures of the current setup. As you can see, it is quite wrong. I just installed a skim port as well, because the installer didn't find it necessary.


  • Jamie Hall
    Jamie Hall Member Posts: 21,094
    At least the man

    used both tappings on the boiler... give him credit for that, perhaps.

    A drop header will give you much dryer steam.  It may also be a little easier to pipe in, all things considered.  Yes, I would use 5 inch for the connection from the drop header to the existing system, and I would use 5 inch for the header itself.  The risers and the pipes coming over and back down to the header can be whatever size Weil McClain recommends for that boiler (yes, I could look it up, but...).  You would connect the two risers to the header, near each other -- say 10 inches apart to 20 , then 10 to 20  inches further along connect a line going and over to the system connection (you might put a king valve in that; there is something to be said for being able to shut off the system and confine the steam to the boiler and near boiler piping from time to time -- but 5 inch valves were not cheap, last I looked).  Then, finally, make your connection down as the equalizer.

    Do it in threaded black iron, or welded steel, please.  Not copper!
    Br. Jamie, osb
    Building superintendent/caretaker, 7200 sq. ft. historic house museum with dependencies in New England
  • lza
    lza Member Posts: 40
    60" wrench

    Haha, have fun wrenching 5" pipe!  You better get the 60" out.  And a 48" for your backup.  Or a team of horses. 
  • Jamie Hall
    Jamie Hall Member Posts: 21,094
    Which is why

    I suggested that welded steel just might be the way to go.  In places where you need to be able to disconnect piping, or need to allow a little give in the assembly -- like hooking up to the existing steam mains -- I'd use flanges welded onto the pipes.
    Br. Jamie, osb
    Building superintendent/caretaker, 7200 sq. ft. historic house museum with dependencies in New England
  • JStar
    JStar Member Posts: 2,752

    5" is correct size according to my charts. It's on the low end, but 4" would be too small.

    We install up to 6" pipe with a 5ft wrench. What's the problem?
  • Prospect_Handy_Man
    Prospect_Handy_Man Member Posts: 32
    5" pipe

    Is what was used with the original boiler piping. But the last two installers used a 3" riser to the system. I just wanted to confirm that it should be 5". Slower steam is better right. On a side note, when a new boiler was being installed at my church, I saw that the original piping to the system was a 6" pipe, and the near boiler piping was only 3" and copper :( I recommended that they re-pipe the near boiler piping with 6" black pipe, since the boiler tapping was also 6". Well my suggestion, being only an amateur was not taken seriously. So the new boiler with the 3" copper still remains. Ughhh
  • Hap_Hazzard
    Hap_Hazzard Member Posts: 2,826
    Header Design

    Since you have a lot of headroom to work with, I'd recommend making the boiler risers as tall as possible and as large as the tappings on the boiler. A long, vertical riser prevents carryover from reaching the header, so the header can separate smaller entrained water droplets.

    The header itself should have at least as much cross-sectional area as the boiler risers combined, this will keep the velocity as low as or lower than it was in the risers.

    Allow at least one pipe diameter between each riser connection, and at least two pipe diameters between the last boiler riser and the first system riser. The system risers should exit at right angles to the header, and the equalizer should come off the end using an elbow the same size as the header. The diameter of the equalizer should remain at least half of the diameter of the header until it reaches with water line.

    These are just the rules of thumb I've picked up here and there, so if the pros tell you anything different, they know better.
    Just another DIYer | King of Prussia, PA
    1983(?) Peerless G-561-W-S | 3" drop header, CG400-1090, VXT-24