Welcome! Here are the website rules, as well as some tips for using this forum.
Need to contact us? Visit https://heatinghelp.com/contact-us/.
Click here to Find a Contractor in your area.

What is this on a 100+ year old system?

Dave2012
Dave2012 Member Posts: 2
in Strictly Steam

Came across this and wondering what this is and what was it's purpose?

image.png

Comments

  • Jamie Hall
    Jamie Hall Member Posts: 24,839

    Honeywell Heat Generator, and it functions — very nicely with no moving parts — to maintain the correct water pressure in the system.

    Don't mess with it! It contains mercury — in fact a pretty fair amount of it — and that is the last thing you want spilled all over the place. But it is completely safe as is.

    Br. Jamie, osb
    Building superintendent/caretaker, 7200 sq. ft. historic house museum with dependencies in New England
    bburd
  • Steamhead
    Steamhead Member Posts: 17,376

    @Dave2012 , I think @Jamie Hall is right, but I also see what looks like a McDonnell & Miller #67 low-water cutoff in the background, that would be used on a steam boiler. Can we see some more pics of this boiler, from the front and the other side?

    All Steamed Up, Inc.
    Towson, MD, USA
    Steam, Vapor & Hot-Water Heating Specialists
    Oil & Gas Burner Service
    Consulting
  • Mad Dog_2
    Mad Dog_2 Member Posts: 7,518

    Mercury repository...Ne mindful Mad Dog

    Consulting by Mad Dog & Matt Jr.
  • EBEBRATT-Ed
    EBEBRATT-Ed Member Posts: 16,467

    probably just used the #67 on a hot water boiler. Also, an aquastat in the picture as well as a stack switch.

  • Steamhead
    Steamhead Member Posts: 17,376
    https://forum.heatinghelp.com/discussion/comment/1801317#Comment_1801317

    If they did it's not the best choice. It's only rated 20 PSI max, and the safety on the usual hot-water boiler is 30 PSI.

    All Steamed Up, Inc.
    Towson, MD, USA
    Steam, Vapor & Hot-Water Heating Specialists
    Oil & Gas Burner Service
    Consulting
  • Erin Holohan Haskell
    Erin Holohan Haskell Member, Moderator, Administrator Posts: 2,354

    Here's the original circa-1910 literature for the Honeywell Heat Generator.

    And here's a cautionary tale about it.

    President
    HeatingHelp.com

    PC7060
  • sopcopotoptop
    sopcopotoptop Member Posts: 25

    It looks incomplete. The tube within a tube appears to be missing as well as the mercury containing lower portion. Modified at some point?

  • mattmia2
    mattmia2 Member Posts: 10,920
    edited July 25
    https://forum.heatinghelp.com/discussion/comment/1806779#Comment_1806779

    I think the top of it is just cut off in that picture. The dish part is the bowl of mercury that is the pressure regulator.

    Or maybe that is just the top dome. I thought i've seen versions that were just that dish before but some googling reveals the pictures I thought i saw had a bottom piece. Looks like they just left the dome in place when the converted to a closed system or an automatic burner.

    sopcopotoptop

Categories