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Steam Boiler problems...oh arent they fun!

Hello all-

I've got a gas powered New Yorker steam boiler (brand new), installed earlier this year. The first couple months it ran great, the radiators all heated, and life was good. More recently it's been causing problems- here's the story- i'll be brief:

I call for heat, it fires up and within 15 minutes all the near piping is good and hot. Some of the radiators will begin to get warm. The the sight glass starts to bounce violently. At about 20 minutes it will bounce low enough that the LWCO will kick in and cut the flame. When it cuts out, the water level in the sight glass stabilizes and returns to 3/4 full. The LWCO thinks for a minute, doesnt add any water, and then the boiler kicks back on. It will continue this, kicking on and off every couple of minutes until finally it turns off and stays off.

I had a plumber take a look. He recommended running 8-way cleaner through it, as i never did, and he said it probably has too much oil. I ran the cleaner through for a couple hours, and then flushed it over and over until the water was clear. I've skimmed it countless times. I also removed the LWCO probe and made sure it was clean. None of this has helped at all.

Plumber stated he thought some of the near piping wasnt done correctly, and this "could" be the cause. But he wants $500 to change it, and im not totally confident that he's going to be any better than the first plumber who installed it. I live in detroit and steam pros are no where to be found.

Could the near piping cause the water level to bounce so much? What else could it be? I've read some forums here that discuss the PH level of the's definitely had a lot of new water added over the past week and it isnt filtered. But would that cause it to turn on and off?
Also, i have the pressure set at 2, but i have the original 0-30 psi pressure gauge on there and it never moves. I havent checked the pig tail but its only been in operation for 4 months. Other ideas?


  • FredFred Member Posts: 8,423
    Post a picture of the boiler and piping above it. It sounds like it needs a good skimming. How are you skimming it? A good skim takes several hours with a very slow steam of water out of a port above the normal water level in the boiler. The stream should be no larger in diameter than a pencil. It is not a process you can rush and just draining some water out of a lower drain won't work. Oils cling to the sides of the boiler so when you drain it, then refill the boiler, the oil just lifts off of the sides and float on top of the water again.
  • Jamie HallJamie Hall Member Posts: 13,115
    That much bouncing on a new boiler very strongly suggests that it needs more skimming -- very slow simmer, very slow release of water from the skim port. You will have to control the thing by hand, to keep it on a slow simmer. You don't want a full boil -- but you don't want it to stop, either. This may take hours -- the better part of a day -- at least.

    Also, adding things -- particularly cleaners -- to boilers can cause this sort of merriment, or at least make it a good deal worse. Some people like a small amount of Steamaster, to control pH.

    The 15 minutes to get things good and hot is a little long, perhaps -- do you have main vents?

    For the near boiler piping -- if you could take several pictures of your setup, from all four sides of the boiler, and far enough to get the near boiler piping in, and post them, folks will comment.
    Br. Jamie, osb

    Building superintendent/caretaker, 7200 sq. ft. historic house museum with dependencies in New England.

    Hoffman Equipped System (all original except boiler), Weil-Mclain 580, 2.75 gph Carlin, Vapourstat 0.5 -- 6.0 ounces per square inch
  • Danny ScullyDanny Scully Member Posts: 1,236
    First things first, pictures please.
  • garethgareth Member Posts: 3
    edited February 2017
    Thanks for the initial suggestions. I'm new to steam heat, and only recently purchased Dan's book and started gathering info from this site.
    Skimming- after your comments i YouTubed some good examples and i was certainly doing it too quickly, and without running the boiler! I will attempt the correct process tomorrow and see what difference it makes.
    Pics- I will take photos of the near piping etc and get them posted! Thank you, already feeling hopeful that the skimming will help!!!
    Main venting- I think you're also right about the main vents. As far as i can find, there is only 1, and it's a 3/4 inch on the return. Most of the mains are still covered in asbestos insulation. I've determined I need to add at least one main vent, but am figuring this is a separate problem..
  • ttekushan_3ttekushan_3 Member Posts: 924
    As everyone else said, pictures will tell us if the near boiler piping is causing the instability.

    But it started out fine.

    I have to wonder if the original installer added an antifoaming agent, maybe a diatomaceous earth powder, to get it to work from the get-go. A blowdown here, a blowdown there and maybe the stuff dissipated. And you are left with the remaining oils or questionable piping to cause problems.
  • EBEBRATT-EdEBEBRATT-Ed Member Posts: 7,196
    The best skim method is Dan's method described in LAOSH and you don't need to keep the boiler running. If you have a drain or a sump pump you can set it up and skim all day without watching it. And it works every time

    Your plumber can become a steam pro. All he needs to do is READ the boiler installation instructions and follow the boiler MFG Instructions for piping and cleaning
  • garethgareth Member Posts: 3
    Update: Today I skimmed the boiler as Dan's method suggests. I started it up after the skim and it's been heating for three hours now, no problems. The water still moves, just not as violently. Perhaps another skim?

    Also, I'm posting pictures of my near boiler piping. Please leave comments on if it looks to be done correctly. And if not, what should be improved?

    The radiators still take 15-20 minutes to really get warm. And the one farthest from the boiler is yet to get warm. I havent found any main vents. It's all older piping, much of it with asbestos and framing built around it in the basement ceiling. What's the easiest way to add a main vent to such things? Cut it and re-thread?

    What else aside from main vents could improve the speed/efficiency?

    Thank you so much for all the help. The skimming saved me from a very cold night without heat!

  • FredFred Member Posts: 8,423
    edited February 2017
    It definitely is not piped correctly but it is very difficult to see enough detail from these pictures. There really isn't a header on there. It doesn't look like the piping what should be a header is at least 24" above the boiler water line. The piping on a Header should be Riser, out of the boiler into header, second riser, out of the boiler (if used) next, on the header, Riser to the main next, second riser to another main next and then the equalizer on the end, after the main risers.
    You probably have a lot of wet steam with the way it is currently piped. I also think I see one riser out of the boiler tee'd right into the bottom of that horizontal pipe. That is a problem. Those risers should tie into the side of a header to allow swing joints. Additionally with that tee, steam comes into that pipe and hits the back side of that Tee and pushes back into the boiler. You don't want that. You also need main venting to move the air out of the mains quickly but I think you need to have a Pro fix that piping first. Where are you located? Maybe we can direct you to a real Pro.
  • AbracadabraAbracadabra Member Posts: 1,948
    Famous vertical header design! Perfect for creating extra wet steam.
  • SteamheadSteamhead Member Posts: 13,929
    To remove any doubt- here is the boiler manual. The piping diagram is on page 17 of the PDF file: I&O.pdf
    All Steamed Up, Inc.
    "Reducing our country's energy consumption, one system at a time"
    Steam, Vapor & Hot-Water Heating Specialists
    Oil & Gas Burner Service
    Baltimore, MD (USA) and consulting anywhere.
  • Bill_Kitsch69Bill_Kitsch69 Member Posts: 24
    The old adage: When all else fails, read the instructions...
    Simple fixes, mentioned above by others.
    Pipe it exactly per the manual.
  • Danny ScullyDanny Scully Member Posts: 1,236
    Well, where to being. First, the front of the boiler is up against a wall. Second, the piping is entirely incorrect. If I'm looking at the picture right I think the dry return is actually connected right into the "header". I think that galvanized tee with the plug in it is the end of the dry return. If it were piped properly, this would be your main vent location. You'll definitely need to have this piped to meet/exceed manufacturer's specifications.
  • JohnNYJohnNY Member Posts: 2,468
    gareth said:

    These are the people we compete with in the field. It's upsetting.
    For troubleshooting and private consulting services, find John "JohnNY" Cataneo here at :
    "72°F Mechanical, LLC"
    Or email John at [email protected]
    John is the Boilers and Hydronic Heating Systems Course Instructor at NYC's Mechanics Institute, a professional Master Plumber, licensed by The Department of Buildings of The City of New York, and works extensively in NYC while consulting for clients in and out of state.
    John also oversees mechanical installations and maintenance for metro-area clients with his family's company, Gateway Plumbing and Heating along with his brother/business partner.
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