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.

Square Plug wrench

ccstelmo
ccstelmo Member Posts: 45
in Strictly Steam

I hate to look dumb, but I must have been asleep when they covered square plugs.

This steam boiler is about 20 years old. Last winter it sprung a leak in the riser of the Hartford Loop. I recently replaced all the piping in the loop because upon examination it was all grotty. This got me to thinking about the boiler itself and I decided to flush it.
Questions:

  1. How do you thoroughly flush a one pipe steam boiler without risking getting caca into the system above?
  2. Is there a special wrench/socket available for square head plugs? The boiler jacket makes this a “recessed “ plug that is inaccessible any other way than with a special tool.

Comments

  • mattmia2
    mattmia2 Member Posts: 14,136

    is the square drive raised or recessed?

  • 109A_5
    109A_5 Member Posts: 2,757

    There is male 4 point (square) and female 4 and 8 point (double square) sockets. There maybe other tools too.

    image.png
    National - U.S. Gas Boiler 45+ Years Old
    Steam 300 SQ. FT. - EDR 347
    One Pipe System
  • kcopp
    kcopp Member Posts: 4,588

    You have a little or no chance of pulling that plug out after 20 years.

    mattmia2EdTheHeaterManMad Dog_2Intplm.
  • mattmia2
    mattmia2 Member Posts: 14,136

    maybe slightly more if it is a raised square plug but you are probably cutting it out. take most of the middle out with a hole saw then cut 2 slots almost to the threads and knock the wedge out with a cape chisel.

    better installers will replace plugs with nipples and caps so they can be removed or are easier to cut out if needed.

    Mad Dog_2
  • ScottSecor
    ScottSecor Member Posts: 1,004

    If they used Teflon tape it might come out with a standard twelve point socket and a very large breaker bar. Pipe wrenches or fifteen inch adjustable wrenches work sometimes with cheater bars (pipe). Unfortunately, after twenty years the heads have a tendency to snap off when you try to remove them.

    Like others suggested, plan on drilling and cutting the plug out.

    Mad Dog_2
  • ccstelmo
    ccstelmo Member Posts: 45

    Thanks, guys. It’s a raised head, 2” up. Do you think it is worth the trouble to flush out this boiler? I’m still wondering about how to keep the water out of the upper reaches of the system.

  • mattmia2
    mattmia2 Member Posts: 14,136

    you can replace existing ells with tees and caps and make a wand out of copper tubing to flush out the bottom of the boiler. if you have wet returns you'd want caps or drains to flush those with a hose. the stuff in the boiler usually mostly came from the returns

  • 109A_5
    109A_5 Member Posts: 2,757

    You could temporarily remove the pressure relief valve as another access port to accomplish your task. Any Skim tapping ? Is the water excessively dirty ?

    image.png
    National - U.S. Gas Boiler 45+ Years Old
    Steam 300 SQ. FT. - EDR 347
    One Pipe System
  • HVACNUT
    HVACNUT Member Posts: 6,991

    That's a factory plug on a steam boiler that's been sitting there for 20 years. It probably needs to be drilled. Even with a breaker bar, it probably won't budge.

  • Mad Dog_2
    Mad Dog_2 Member Posts: 8,322

    Yes...its usually always worth getting the Splunck out. Mad Dog

    Consulting by Mad Dog & Matt Jr.
  • ethicalpaul
    ethicalpaul Member Posts: 7,799

    I'm a little confused about your concern about fouling the system above the boiler.

    What are the details of your flushing plan?

    I would have thought the time to flush it would have been when you had the hartford loop piping removed from the boiler, then you wouldn't need to worry about this plug.

    What plug are you thinking of?

    NJ Steam Homeowner.
    Free NJ and remote steam advice: https://heatinghelp.com/find-a-contractor/detail/new-jersey-steam-help/
    See my sight glass boiler videos: https://bit.ly/3sZW1el

Categories