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Fuel Nozzle dilemma! Wisdom welcome!

Hello, fellow steamheads.

I've posted here before about the clanks and bangs in my cranky old steam system, which features any number of lousy quirks, like zero main vents, and a blatantly badly-piped boiler. One of the three mains feeds two radiators, one feeds four, and one feeds eight. Not ideal. Besides clanks and water-hammer, we were hearing lots of bubbling and seething through the radiators, even on upper floors.

Recently, the engineer cleaning my Slant/Fin Intrepid TR-40 PZ suggested that a lot of the noise trouble was because the fuel nozzle (1.50) was too large: it was so dramatically over-boiling the water, that it was throwing water up into the header and the mains. He replaced it with a 1.10 nozzle (Kobelco, possibly?), and it had a GREAT impact on the noise. The clanking stopped, not to mention the unpleasant sound of surging water that came from some of the radiators.

But then there was a problem with... the actual heat. While it was natural to expect that the 1.10 nozzle would boil the steam slower, leading to longer run-up times and slower heating, overall, the system is simply produced less steam, and heated the radiators less effectively, which in turn radiated less. One radiator - a crucial one, but which was at the tail end of the its main after 7 others - didn't heat at all.

While I was writing this post, he came back (very graciously) and switched out his 1.10 and installed a 1.35 nozzle, and now the system is working more robustly. The dead radiator is heating again. And some - not all - of the bubbling is back.

So, it's not an emergency anymore. We're not freezing. But we're obviously in a dance between noise/water in the system, and being too cold. So I wanted to put this on The Wall and see whether anyone had any similar experiences, any similar nozzle adventures, and any wisdom gained.

Any and all thoughts welcome, and thanks to the great HeatingHelp community.



    EBEBRATT-Ed Member Posts: 15,511
    You need to fix the lack of venting. You may have other issues but that is the first thing to fix. Also check the pitch of all radiators and piping. Post some pictures
  • Big Ed_4
    Big Ed_4 Member Posts: 2,780
    Yes, I agree it sounds venting. ...

    You want to stay within 80% present of the max input .Pump pressure and nozzle size .. Stack temperature will tell you if too low . 400* good

    When it is breaking steam is the gauge glass bouncing .. If so clean and skim the boiler water

    I have enough experience to know , that I dont know it all
  • STEVEusaPA
    STEVEusaPA Member Posts: 6,506
    An engineer cleaned your boiler?
    Robert O'Brien
  • SteaminTed
    SteaminTed Member Posts: 16
    Thanks to you both! Yes, the venting has been at the top of my not-yet-done list for a while. Then I had a respected steam guy check out the system; his opinion was that the piping on the boiler was so crazy that repiping it was essential to addressing most of the problems. (But of course it's expensive. No whining, it just is.) So I lost the mo on the vents for a while, but will probably install three or four of them in the spring.

    - ted

    ps - Photos of boiler/piping attached. Note the step-down pipe sizes, the header with a riser (why?) leading to the mains. And the mains coming off that vertical element instead of a horizontal one.

  • There’s a limited range of nozzles you can fire in any boiler. You don’t get to pick just any size. I doubt very much the issue is nozzle size. As you already stated, the piping is bad, and so is the venting. A new nozzle won’t fix that. 
    New England SteamWorks
    Service, Installation, & Restoration of Steam Heating Systems
  • Steamhead
    Steamhead Member Posts: 16,823
    Wow- I thought I'd seen some badly piped Intrepids, but this is worse.

    That boiler needs a 3-inch header. Period. Get it properly repiped and watch how much better it works.

    For an in-depth look at how steam distributes in a proper header on an Intrepid, go here:

    All Steamed Up, Inc.
    Towson, MD, USA
    Steam, Vapor & Hot-Water Heating Specialists
    Oil & Gas Burner Service
  • Kickstand55
    Kickstand55 Member Posts: 110
    I see one big problem! The boiler is dusty. You can't have a dusty boiler. In reality, that's a sign of workmanship or the lack thereof.
    The Copper riser to the header looks like it may be less than 24" above the water line, a flat 90 degree bend helping to send wet steam and boiling hot water upwards. Lack of pipe insulation. I can't see the gauge well but is the pressure above 1-1/2 psi?
    How about the pressuretrol pigtail. Has it been removed and checked for obstruction?
    Have the flue passages been thoroughly been brushed and cleaned along with cleaning and checking the firebox area. Any air leaks in the combustion area. That can affect performance and give false combustion readings.
    I'd like to remain humble and will try my best.
    My concern with my customers and folks looking here to remedy problems and get advice and that they receive good council on issues. Many of us here want to do that, and from what I see, it's happening.
    There are proper ways to service a steam boiler, in fact any boiler or furnace for that matter. If there are shortcuts, unpleasant things can happen. A contractor should inform their customer all pertinent operation measures and explain what needs to be done on an annual basis or more frequently if necessary. Plus, any other repairs or maintenance to keep a system running well. You can ask them what you should be doing and what they do. If you don't get good answers, you may want to look elsewhere. Few mechanical contractors are good with steam these days. I've heard something about the "Dead Men" and tales of steam heating.
    I hope this will help.
  • Big Ed_4
    Big Ed_4 Member Posts: 2,780
    No miracles , no off or one switch here . What is expensive ...
    I have enough experience to know , that I dont know it all
  • SteaminTed
    SteaminTed Member Posts: 16
    Many thanks to all - as usual, the perspective and collective wisdom of The Wall is the greatest resource for the Trade of the Ones Who Went Before. Will update (eventually) for sure.

  • clammy
    clammy Member Posts: 3,110
    Aside from the poor near boiler piping ,when was the last time it was properly service ,fire and water side . I know it’s not the most exciting job and most bs there way around it but unless it’s known that it is clean it’s one less thing that will effect both performance and fuel usage . The boiler should be fired at what it rated for if you want to under fire it the you should figure your edr and adjust your nozzle size if your way over sized boiler wise . Not a big fan of slant fin steamers but if piped w a over sized header they can run fairly well and produce a stable water line .if and whenever u do get it serviced be there make sure they pull the top open the front and brush each section and vacuumed the chamber ,check chimney base and perform a smoke test and a combustion test and of course change the filter strainer and nozzle aside from cleaning burner fan and housing and all the rest of the stuff there suppose to do. It s really a thankless job lol but has to be done . It usually isn’t done properly for 150.bucks at least by me . I see your from across the river there’s really seems to Be a shortage of decent not only steam but any heating contractors . I think I would have a talk w the guys or company who installed and service it if there no help you need to find a real heating contractor ,if there’s the one who installed it , I would find a new contractor they are clueless there’s no excuse for that install except the lack of a professional and any type of pride in workmanship just a throw in drive by which no one deserves unless it’s for free and at the price point you get what u paid . Peace and good luck
    R.A. Calmbacher L.L.C. HVAC
    NJ Master HVAC Lic.
    Mahwah, NJ
    Specializing in steam and hydronic heating
  • mikespipe
    mikespipe Member Posts: 36
    Besides the bad piping which should be fixed the lack of insulation is a big issue the hottest pipes in the house are those coming from the boiler. Every pipe is a radiator so if you want to spend a lot of money heating your furnace room instead of your living space don't put it on. but if you put 1 inch thick insulation on the steam risers in the Boiler room the steam will leave that room at about the same temp it came out of the boiler. if your not living in the basement insulate all the steam pipes there. the increase in available heat in the living space will be great and the cost of heating the house will be greatly reduced.. the cost of the insulation will probably be recouped in the first year.
  • clammy
    clammy Member Posts: 3,110
    On a side note every steam main leak I have ever repaired was always on a main which had no insulation and if it did not have a sag holding water it had grooving on the bottom side of the piping. . I also have seen this happen on mains which had no insulation and had little to no main venting which does not help the situation . The easiest way I have explained this to a home owners is ya wanna put the heat where it’s needed not where it ain’t and the cause and effect of non insulated steam mains is hot basement cold living area longer heat cycles higher heating fuel bills and less comfort and the knowledge that sooner then later your uninsulated main will come home to roost and leak or create more rust and mud that will be coming home to either your wet retrying or boiler to do no good . The result of insulating mains are usually two improvement that is felt by the result are heat usually where it never got to before and lower fuel bills . This is the most common outcome peace and good luck clammy
    R.A. Calmbacher L.L.C. HVAC
    NJ Master HVAC Lic.
    Mahwah, NJ
    Specializing in steam and hydronic heating