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Trouble with new steam boiler: Burnham IN6PV

JPL941 Member Posts: 48
Hello everyone and thank you in advance for taking the time to read about my steam issue. Hopefully you all can help guide me on how to fix this system.

When I first moved into my home, there was an EFM Steam oil burner in place. I called EFM and it was OBD-840 C3, it had a gross output of 268000 btu and produced 840 sqft of steam. After running it, it began to leak a terrible odor so I had it replaced. Also regarding the original boiler, I was told it was down fired to 2.? gpm something (I can't remember the exact number).

When I performed an EDR calculation in my home, I got a total of 327.15. If I added pick up factor of 1.33, it totaled 435 (please keep in mind I have two radiators disconnected so the EDR dropped into the high 200s unless you included pick up factor). I chose the Burnham IN6PV which totaled 450 sq ft steam. During the summer months, everything would heat up fine but I can't remember if I let them totally heat up or just turned the system off when they felt hot and maybe there were partially heated (it was raising the house temp into the 80s).

The steam system services 6 convectors and one radiator (turned off) on first floor and 4 radiators on the second floor. I have changed all the radiator traps that service the convectors and the radiator traps of the Dunham Trap System. I didn't replace the second flood radiator traps just yet.

When the boiler was started at it's normal water line, it was running approximately 10 minutes at a time and turning off due to LWCO. At that point, I increased the amount of water to about one inch below the top portion of the sight glass. Now it's able to heat the entire downstairs before it says LWCO. Once the downstairs gets heated, It basically hits temp and the radiators upstairs never get hot. If it do let it run for a long time, the system cycles on and off LWCO until the second floor is hot. Each time, the water line returns to about the starting point (within a half inch when cold and maybe 1.5" when hot ---- please see picture with clothingpins - One is starting water line and the other shows how far down it drops until it hits LWCO). At that point all the water just rushes back and fills the system. The condensate never seems to return rapidly during operation- it's like there is a vacuum drawing all the water out of the boiler. As a matter of fact, the second floor radiator which is the shortest run of the main supply seems to have a wet steam sound until it's gets hot, then it sounds normal.

Just to experiment, I turned all four radiators on the second floor off and increased total thermostat temp. Even while servicing the first floor, it hit LWCO and all the water would rush back after it was turned off.

From the pictures below, it starts at a 2" header/riser out of the boiler and then goes to a 4" bifurcation which is reduced to 2.5 " supply mains. From there the longest line is maybe 60 ft and the shortest is 20-25ft or less.

Aside from having to install pipe insulation, I'm not sure what else to do. I know the header isn't a drop header, but looking at the setup, it seems that the steam has to travel up that long pipe initially and it doesn't need one (wet steam would fall back down to condensate pipe {I'm not entirely sure if any of that makes sense}). Also, are there two equalizers? How do you pipe to manufacturer's specs and include the dunham steam return - can you? Can you replace those brass check valves? Should a repiping include removing that large 4" vertical pipe and somehow tie the mains differently?

All, thank you again.


  • Steamhead
    Steamhead Member Posts: 14,476
    Well, for starters, the boiler is piped totally wrong. Look at the piping diagram in the instruction manual and you'll see the difference. Improper piping can cause water to leave the boiler along with the steam.

    Not sure if the air trap still has a vacuum check on it- if so, remove it, since this can cause water to not drain back as it should.

    You need a Steam Man. Where are you located?
    All Steamed Up, Inc.
    Steam, Vapor & Hot-Water Heating Specialists
    Oil & Gas Burner Service
  • JPL941
    JPL941 Member Posts: 48
    Thanks for your quick response. I'm located in Northumberland, pa about an hour east of state college pa. I did see the piping was wrong. Could you repipe into the dunham trap as originally designed? And when you say vacuum check, you're talking the thing on top of the air eliminator?
  • Steamhead
    Steamhead Member Posts: 14,476
    edited December 2016
    I know exactly where that is- passed through there on my way to Williamsport to play in the Liberty Classic. About a 2-2.5 hour drive from Baltimore, depending on how bad the traffic is at Shamokin Dam.

    I'd have to get a closer look at the piping to answer your first question.

    Yes, the vacuum check is the thing screwed into the air eliminator. Unscrew it and see if that helps.
    All Steamed Up, Inc.
    Steam, Vapor & Hot-Water Heating Specialists
    Oil & Gas Burner Service
  • KC_Jones
    KC_Jones Member Posts: 4,653
    Also you oversized it. Should have used an IN5 max.
    2014 Weil Mclain EG-40
    EcoSteam ES-20 Advanced Boiler Control
    Boiler pictures updated 2/21/15
    Hatterasguyj a_2
  • Jamie Hall
    Jamie Hall Member Posts: 15,858
    Also your cutout pressure (2 psi as I read it) is high. That's not going to help a bit. Something you can do today -- go down there and dial that cutout back down as low as it can go without falling apart.
    Br. Jamie, osb
    Building superintendent/caretaker, 7200 sq. ft. historic house museum with dependencies in New England
  • Fred
    Fred Member Posts: 8,518
    As has been said, that boiler is piped completely wrong. Has the boiler ever been skimmed? I don't mean drained and refilled, I mean a real (probably several) long slow skims from a skim port above the boiler water line. Oils sitting on top of the boiler water will cause water to push back into the wet returns. Also, the water level is too high. Reduce it to no more than 3/4's of the sight glass. You're not leaving much room for a steam chest in that boiler. Skim, Skim, Skim.
  • JPL941
    JPL941 Member Posts: 48
    Hello everyone. I disconnected the air eliminator cap to allow air flow, it did not help. I decreased the pressure, it did not help. I decreased the water content - it hit LWCO more than ever. And yes, it's been skimmed many times. I'm going to have someone come in and repipe the entire set up. I'm not sure how to repipe into the dunham trap system. Do you have two equalizers? Two hartfords? - I wrote an email to burnham to get their opinion. Also should there be water in the dunham return system? This is the first year in maybe 8 years that the system has been used. If water should be there, my guess is it evaporated (i'm not an expert on this stuff). Thanks again.
  • Ironman
    Ironman Member Posts: 6,367
    edited December 2016
    With the water line that high and the riser?? coming horizontally right of the boiler (instead of at least 24" above the water line), you basically turned it into a hot water boiler with a restricted return.

    And, are my eyes deceiving me or is the water heater supporting the steam piping?
    Bob Boan
    You can choose to do what you want, but you cannot choose the consequences.
  • j a_2
    j a_2 Member Posts: 1,796
    Getting some good advice here so what a mess starting with the oversizing,,and then the mess of piping....Find a real good contractor close by...
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