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    Is my steam boiler way oversized? (46 Posts)

  • livinthesteamdream livinthesteamdream @ 10:35 PM
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    Is my steam boiler way oversized?

    I just made it through my first winter **glad it was the worst I've seen in nearly 2 decades** in an old house with steam heat. Although I love the heat from my steam radiators, I hate my oil bill. ;)  This got me researching steam heat leading to this site and Dan's books. The house is a large historic home with 25 radiators with a 2-year old Burnham V908 supposedly rated at 1,000,000 BTUs an hour. After fixing several return leaks that were causing it to short cycle and feed water, and some work by some good steam pros I found here, it's now only short-cycling due to pressure...a lot! I measured all the rads for square feet of EDR, and found my total to be 1,443.3 for the entire house. If I'm doing this correctly, I multiply that by the 240 BTUs/sq ft of EDR giving me a required boiler size of 346,392 BTUs. Do I then need to multiply that by the 1.33 pickup factor for steam bumping that size up to 460,701 BTUs? I'm trying to get an idea of how oversized I am and what options I have.
    1) Am I right in the boiler size I need? 2) If so, am I pretty much looking at having to yank the 2 year old boiler and start over since it seems to be 2-3 times larger than it needs to be (if I'm figuring this correctly)?3) Is there anything I can do that will lead to moderate efficiency despite the oversizing?
    Any assistance is appreciated, and if you need more pics or information just let me know.
    twice the boiler I need, short cycling, atrocious near boiler piping, excessive fuel consumption, water hammer throughout...you name it I got it in my system O_o
  • livinthesteamdream livinthesteamdream @ 10:38 PM
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    and yes...

    I realize the near boiler piping is terrible! They apparently re-used the old header pipe...and didn't really know what they're doing.
    twice the boiler I need, short cycling, atrocious near boiler piping, excessive fuel consumption, water hammer throughout...you name it I got it in my system O_o
  • SWEI SWEI @ 10:43 PM
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    Simpler

    V908 is rated for 2,888 square feet of EDR.  You have 1,433.  Your boiler is twice the size it needs to be.
  • nicholas bonham-carter nicholas bonham-carter @ 11:28 PM
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    Down rating the burner?

    If you can find a good steam man, or burner man, maybe the burner could be derated a bit for some savings.
    Even more important would be making sure the air can get out through the main venting system.
    Is this a 1-pipe, or 2- pipe system?--NBC
  • livinthesteamdream livinthesteamdream @ 8:48 AM
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    if this was your house

    What would you do with this boiler? Try to sell this & replace it with a properly sized boiler? Is there a market for a used boiler such as this? This was installed by a local company a year and a half before I got the place so its only 2.5 years old. I was purchasing roughly 600 gallons of oil from them each month with it set fairly low at 58-62 due to issues stemming from the oversized boiler and improper piping resulting in a ton of water hammer. I'm just trying to ensure next winter isn't this uncomfortable & expensive.

    The most local pro I found here addressed venting with the addition of 2 Gorton #2s, a #1, and replacement of 2 crossover traps. Oh, they added a vaporstat as well.
    twice the boiler I need, short cycling, atrocious near boiler piping, excessive fuel consumption, water hammer throughout...you name it I got it in my system O_o
  • livinthesteamdream livinthesteamdream @ 8:50 AM
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    2-pipe

    I forgot to mention that in the last post, NBC.
    twice the boiler I need, short cycling, atrocious near boiler piping, excessive fuel consumption, water hammer throughout...you name it I got it in my system O_o
  • nicholas bonham-carter nicholas bonham-carter @ 10:26 AM
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    Dealing with oversized boiler

    I would try to get the supply piping straightened out first, and make sure with a low-pressure gauge, that the venting was adequate, (I have 18 Gorton 2's on a 1,050,000 boiler with 55 rads).
    Was a combustion test ever done? Is the burner 2-stage?
    A boiler that big is difficult to move without complete disassembly. If you were to replace it, a pair of smaller 200 MBTU boilers, staged on pressure, might be more economical.
    Is gas available?--NBC
  • livinthesteamdream livinthesteamdream @ 11:02 AM
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    burner

    The burner us a Beckett CF1400 running a 5.5 gal nozzle. It will accept down to a 4 so should that be the first change? I haven't had a combustion test done since I've owned it. I don't mean to be stupid, but I don't know about the 2-stage part. The specs mention a Linkageless Low/High/Low feature. Is that what you're referring to?

    We do have natural gas in the area & I have a meeting scheduled with the local supplier on Monday to see if that would be feasible. Without getting into price, the conversion for this was moderately costly considering all the other issues I still have to correct with the steam system overall such as near boiler piping, venting, pipe insulation, etc.

    I almost feel like I'm just throwing money away.
    twice the boiler I need, short cycling, atrocious near boiler piping, excessive fuel consumption, water hammer throughout...you name it I got it in my system O_o
  • SWEI SWEI @ 12:37 PM
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    You might

    be able to remove some sections when the repipe is being done, and end up with a V-905 when you're done.

    Installing a smaller oil burner will cost almost as much as a NG conversion burner would.
    This post was edited by an admin on April 9, 2014 12:38 PM.
  • livinthesteamdream livinthesteamdream @ 1:02 PM
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    removing sections?

    First of all, I want to thank all of you who have posted thus far. I really appreciate your insight & assistance through this process. I had wondered if removing sections was a possibility, but I didn't want to sound (really) stupid. So that is actually feasible? If the smaller oil burner is the same cost then cheaper NG is the way to go...assuming it is available to me. What all does removing those 3 sections entail?

    What is best overall game plan I have to not have to install a new boiler or completely abandon steam heat? I do still like the steam heat & the fact that I'm using the original 100-yr old heat system in my historic home. I just want it to work properly and as efficiently as it can so my family can be comfortable.
    twice the boiler I need, short cycling, atrocious near boiler piping, excessive fuel consumption, water hammer throughout...you name it I got it in my system O_o
  • Jamie Hall Jamie Hall @ 4:01 PM
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    No need to abandon

    the steam heat!

    Removing sections is a bit of a hassle -- I wouldn't call it a do it yourself project, by any stretch.  However, it certainly isn't impossible.  A good steam contractor (look in Find a Contractor, by State for one near you -- or just tell us where you are and we may know someone) could do it, and at the same time tidy up the near boiler piping and, if you find you have access to natural gas, install a gas burner.  All at the same time...
    Jamie

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

    Hoffman Equipped System (all original except boiler), Weil-McClain 580, 2.75 gph Carlin, Vapourstat 0.5 -- 6.0 ounces per square inch
  • livinthesteamdream livinthesteamdream @ 4:21 PM
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    10-4 on the pro

    I have reached out to local pro I found here, so I'll definitely not be attempting this on my own. I'll have get an idea of cost for all of that. I'm just glad I wouldn't have to completely start over due to the oversizing deal. I was worried about that.

    Any other ideas of how to make this work?
    twice the boiler I need, short cycling, atrocious near boiler piping, excessive fuel consumption, water hammer throughout...you name it I got it in my system O_o
  • heatpro02920 heatpro02920 @ 4:52 PM
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    If I were doing the job

    I would try to talk you into getting NG if it is available first off... {check costs to bring in service and make chimney work}...

    Then I would contact US and see what the cost of new rods, jacket side panels, seal, ect looks like.

    Then contact Carlin for a gas burner...

    I would also repipe everything in your pictures, and insulate EVERYTHING.. Get the piping rite for what is there, kind of a start over and see where it ends up job, nothing I would tackle in the winter months, but now you should be good to get the research done, find the rite pro and be happy with your 100 year old heating system..

    There is a market for that becket burner, ebay would be the best place to unload it if you can not find a buyer here on our classifieds and your contractor isn't interested...

    good luck, looks like a fun project..
  • livinthesteamdream livinthesteamdream @ 5:16 PM
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    good info

    Thanks for the information heatpro! I'll be finding out about NG this coming Monday when I meet with Mountaineer Gas. If I downsize the boiler to 5 sections (V905), what size NG burner would I be looking at for this setup? I'll try to get some cost info together.
    twice the boiler I need, short cycling, atrocious near boiler piping, excessive fuel consumption, water hammer throughout...you name it I got it in my system O_o
  • heatpro02920 heatpro02920 @ 8:16 PM
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    Burner size

    I would call Carlin {I am starting to use them more and more}, or maybe a Power Flame J15 ... http://data.powerflame.com/support/supportdocs/Catalog/pdf/type-ja/JAHTD-Bulletin.pdf
    or http://www.carlincombustion.com/gas-oil-burner-products/burners/commercial-burners-gas-fired/201-gas-burner/ I just ordered one of these for another job...
    I think I would lean towards the carlin, but make sure it will be ok in that boiler first, I never personally installed that one... Tim McElwain under the gas topics would be the best to tell you which burner to use, that is who I would call to ask... He has probably installed one or knows of someone who has already in a similar situation...
    This post was edited by an admin on April 9, 2014 8:23 PM.
  • livinthesteamdream livinthesteamdream @ 9:21 PM
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    burner post added

    Thanks again heatpro. I just posted the NG burner question on Tim's gas page so I'll see what he has to say. Man, this seems like it's going to be a ton of work....cut a pretty much new boiler in half, repipe it, convert to natural gas and pipe that in, add venting. add insulation, trace leaks, etc
    twice the boiler I need, short cycling, atrocious near boiler piping, excessive fuel consumption, water hammer throughout...you name it I got it in my system O_o
  • Probably a litle more sane approach.....

    would be to first convert to natural gas and simply fire the boiler at the proper rate.  Most gas fired boilers seem to work fine with a 50 to 60% down fire, in fact Burnham probably has this as a factory approved high/low set up for the boiler.    Properly tuned, you'll probably see a 3 to 4% increase in firing efficiency when running at these low fire rates.  In this case, you want to keep the boiler oversized to gain heat exchange efficiency, but cut the firing rate.
    Over your current set with oil, you'll probably see at least  60 to 70% drop in fuel costs just making this change due to much cheaper natural gas, and much more efficient boiler and system operation.
    Also, now that you have a huge boiler with a small fire, the need for correct piping above the boiler drops dramatically because the water and steam will separate much better inside the boiler and there will be much less reliance on the external piping.
    This will buy you some time before rebuilding the header.
    The Steam Whisperer (Formerly Boilerpro)
    Chicago's Steam Heating Expert


    Noisy Radiators are a Cry for Help
    This post was edited by an admin on April 10, 2014 8:19 AM.
  • livinthesteamdream livinthesteamdream @ 8:38 AM
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    that would be much easier

    I wasn't aware that you could do that much of a downfire, but that would be way easier of a progression for me! I had tried to call Burnham yesterday but they'll provide no support since I'm not a contractor. Should I find the closest dealer to get the information I need in regard to which burner to use in this setup for that downfiring rate and naturally cost? Or can you suggest a burner? The Carlin 201 says its from 150k BTUs to 399k BTUs so I was thinking the Carlin 301. Anyone know about the Carlin EZ model? Then, if I can find a local burner specialist I could be set. That buys me time to get the header redone as well. However, I would like to try to have all these issues resolved by next winter. I'm currently not using the boiler anyway despite the temperature still being chilly so if I could get the burner done ahead of time I could actually test it out this spring. My wife would love to not be cold!
    twice the boiler I need, short cycling, atrocious near boiler piping, excessive fuel consumption, water hammer throughout...you name it I got it in my system O_o
  • SWEI SWEI @ 10:40 AM
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    Mountaineer Gas

    is in West Virginia.  Don't recall any pros hailing from those parts posting here, but I haven't been around all that long.

    "Nearest dealer" is pretty much a crapshoot.  Better to find someone with proper conversion burner training, hopefully with some steam background.  Tim McElwain might have someone he can refer.
  • Tim McElwain Tim McElwain @ 11:08 AM
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    Oversized for sure

    My e-mail answer is below to SWEI who contacted me about this posting I also got the message over in the gas section, I do not know anyone in the W Va. area but will look into it.


    Not off hand I will look into it. I am getting ready for a class so it may take a while (it is getting warm hopefully). With Burnham getting info when the word conversion is mentioned is tough. I have in the past with commercial boilers knocked them down a couple of sections (a lot of bull work). Cost begins to be a big factor Dave Brunnell had a good idea for a temporary fix so the customer can budget things out.

    Daves answer:

    Probably a little more sane approach.....
    would be to first convert to natural gas and simply fire the boiler at the proper rate.  Most gas fired boilers seem to work fine with a 50 to 60% down fire, in fact Burnham probably has this as a factory approved high/low set up for the boiler.    Properly tuned, you'll probably see a 3 to 4% increase in firing efficiency when running at these low fire rates.  In this case, you want to keep the boiler oversized to gain heat exchange efficiency, but cut the firing rate.
    Over your current set with oil, you'll probably see at least  60 to 70% drop in fuel costs just making this change due to much cheaper natural gas, and much more efficient boiler and system operation.
    Also, now that you have a huge boiler with a small fire, the need for correct piping above the boiler drops dramatically because the water and steam will separate much better inside the boiler and there will be much less reliance on the external piping.
    This will buy you some time before rebuilding the header
  • Tim McElwain Tim McElwain @ 11:10 AM
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    Maybe Steamhead

    would make a journey over into nearby West Virginia if the price is right.
  • Steamhead Steamhead @ 11:49 AM
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    We did

    and the OP says it's running better after some repairs we made (vents and crossover traps), but still using a lot of oil. This is a Hoffman Vapor system.

    One thing to be determined is whether enough gas is available from the street main to fire that boiler. Then we'll know if converting is even possible.

    We did not open the boiler when we were there to see how dirty the fire side is, but given what we usually see, I expect it would take several soot-vac bags to get it clean. We just ran out of time that day.

    But there's nothing about this system that can't be fixed.
    "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.
  • Tim McElwain Tim McElwain @ 4:04 PM
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    The last few jobs

    we did with low pressure available from the gas supplier was to install a large line running from the meter to the boiler. In one case it was about 45 feet of 3" welded pipe. That unit and the others are running fine with no problems this winter. All of those boilers were HB Smith two of which were in churches with 1,250,000 on one and the other 950,000 BTU's. All these are steam using Power Flame combination oil/gas burners with low fire high fire adaptation. All you need is money!

    All of these jobs have seen over the last three years 25 to 30% reduction in cost to operate and the 1,250,000 has seen almost 50% as it was originally only set up on oil to run on low fire, that gets expensive. The church actually paid for the entire installation with the savings on fuel costs the first year.
  • Jason Jason @ 8:17 PM
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    L/h/l firing

    In the meantime doesn't that boiler have a low fire hold switch. That would reduce it by about 40% until the gas comes and should still heat well.
  • livinthesteamdream livinthesteamdream @ 9:14 PM
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    yes to the low hi low feature

    But Idk how to set that up. Is it a pro type job or are there steps to follow?
    twice the boiler I need, short cycling, atrocious near boiler piping, excessive fuel consumption, water hammer throughout...you name it I got it in my system O_o
  • Dave in QCA Dave in QCA @ 1:23 PM
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    For What it's Worth

    Just wanted to let you know that I have an oversized boiler similar to yours, except mine is a Weil-McLain 680. I really only needed a 580, which will allow for future restoration of parts of the steam system that are not currently connected. Because I wanted a 2 stage burner, and WM had only approved a 2-stage burner on a 680 and larger, that is what I ended up with. At the present time, it is firing on Low Fire, a little less that 50% of its full rating. It works great! 82-83% efficiency and 34% less than my old gas boiler.

    As a general rule of thumb, most power burner boilers can fire at 50% with little loss in efficiency and sometimes, actually more efficient that firing at 100% of capacity.

    As second benefit, it doesn't work the boiler near as hard and you'll probably find that it will have a longer life as a result.

    If it were my boiler, I'd convert to gas and tune the thing at 50% of it's full rating ASAP. I would not bother taking sections out, it's too much bother and cost (new jacket panels) and not really necessary.
    Dave in Quad Cities, America
    Weil-McLain 680 with Riello 2-stage burner, December 2012. Firing rate=375MBH Low, 690MBH Hi.
    System = Early Dunham 2-pipe Vacuo-Vapor (inlet and outlet both at bottom of radiators) Traps are Dunham #2 rebuilt w. Barnes-Jones Cage Units, Dunham-Bush 1E, Mepco 1E, and Armstrong TS-2. All valves haveTunstall orifices sized at 8 oz.
    Current connected load EDR= 1,259 sq ft, Original system EDR = 2,100 sq ft Vaporstat, 13 oz cutout, 4 oz cutin - Temp. control Tekmar 279.
    http://grandviewdavenport.com
  • livinthesteamdream livinthesteamdream @ 1:55 PM
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    sounds like the plan

    Thanks Dave. That definitely sounds like the way to go. I'm hoping I hear good news about the gas supply Monday. However, it seems as if even low pressure supply may still be ok assuming I size the pipe from the meter in sufficiently. Does anyone else have positive experiences with low pressure NG running a boiler of this size?
    twice the boiler I need, short cycling, atrocious near boiler piping, excessive fuel consumption, water hammer throughout...you name it I got it in my system O_o
  • Tim McElwain Tim McElwain @ 7:30 PM
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    I have commisioned well

    over 100 boilers all of which are in the inner city with gas pressures in the mains of less than 1/2 a pound pressure. Most of the mains run 8 to 10" W.C. pressure all the time. In extreme low temperatures the pressure my drop down to 5" W.C. but piping is sized from the meter to the boiler to compensate for that. Your installer of the gas line should take that into consideration when sizing the pipe from the meter to the boiler.
  • livinthesteamdream livinthesteamdream @ 8:20 PM
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    So I should be good then?

    Thanks for the expert information, Tim. I appreciate you weighing in on my situation. So it sounds like if the piping from the meter into the boiler is sized properly I should be good regardless of whether or not the NG main is delivering high or low pressure, correct?
    twice the boiler I need, short cycling, atrocious near boiler piping, excessive fuel consumption, water hammer throughout...you name it I got it in my system O_o
  • Tim McElwain Tim McElwain @ 9:07 PM
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    Make sure you get a good steam tech

    to do all the piping and combustion set up along with a combustion analysis.

    On low pressure main systems you will never see high pressure. High pressure systems range from 25 pounds to 100 pounds pressure then reduced to less than 1/2 a pound at the internal regulator before the meter.
  • Low gas pressure

    Chicago is almost all low pressure mains and we have lots of really, really big boilers. Typical courtyard buildings are running 2.5 million to 3 millions input boilers and 500,000 btu input water heaters, all off low gas pressures.  The key is sizing the gas piping correctly. 
    The Steam Whisperer (Formerly Boilerpro)
    Chicago's Steam Heating Expert


    Noisy Radiators are a Cry for Help
  • livinthesteamdream livinthesteamdream @ 11:58 AM
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    I just met with Mountaineer Gas

    and they said that they provide 7 inches w.c. and up to 2 PSI which would require a pressure regulator. They're even willing to trench and move the meter to the left side of my house to keep it off the front and eliminate roughly 50-75' of pipe I would have had to run in to my boiler room! Additionally, their availability to do this work was excellent.
    Now that I'm good NG-wise, what burner should I use? I know the Carlin 201 is 150,000-399,000 Btuh, and the 301 is 401,000-1,100,000 Btuh. My boiler is currently the 1,000,000Btuh, but it the more appropriate size figuring square foot of EDR with the 1.33 pick up allowance for steam was around 460,000Btuhs.
    OR, would a PowerFlame burner be a better option? What have you guys seen as far as gas burners. I'm trying to sort everything out burner-wise keeping my currently twice the size boiler.
    Also, MG mentioned using 1" steel pipe from the meter to the boiler? Does that sound right? My guess is around 30' of piping with all the bends...
    twice the boiler I need, short cycling, atrocious near boiler piping, excessive fuel consumption, water hammer throughout...you name it I got it in my system O_o
  • go to the Burnham site

    and check out what the factory gas burners are for those boilers. 
    The Steam Whisperer (Formerly Boilerpro)
    Chicago's Steam Heating Expert


    Noisy Radiators are a Cry for Help
  • Steamhead Steamhead @ 11:24 PM
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    One-inch pipe won't cut it

    unless they figure on the entire gas distribution in the house running at 2 PSI, and even then I'm not sure. Have to look it up but I'm not at the office.

    Burnham offers Beckett and PowerFlame burners for the V9A series boilers. PowerFlame would be the better bet, since they offer lo-hi-lo firing in smaller burner capcities than Beckett.
    "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.
  • livinthesteamdream livinthesteamdream @ 11:44 PM
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    1" did seem low

    considering the way everyone wrote about proper sizing from the meter to the boiler. I'll await your guidance there, Frank. One question, though...although my boiler should really be in the V904-V905 range, we will use the PowerFlame burner setup for my actual boiler (V908) and downfire with the low high low feature? Is my understanding of this process correct? What else is involved in that setup?
    twice the boiler I need, short cycling, atrocious near boiler piping, excessive fuel consumption, water hammer throughout...you name it I got it in my system O_o
  • Steamhead Steamhead @ 12:23 AM
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    That's what I'm thinking

    the combustion test will determine how low we can go. We don't want to get the stack temp so low that the flue gases condense inside the chimney.
    "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.
  • livinthesteamdream livinthesteamdream @ 11:52 PM
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    Is there any downside

    to a combination gas/oil burner beyond what I assume to be a higher price? I see PowerFlame has those as mentioned in the Burnham manual.
    twice the boiler I need, short cycling, atrocious near boiler piping, excessive fuel consumption, water hammer throughout...you name it I got it in my system O_o
  • Steamhead Steamhead @ 12:26 AM
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    It would give you some flexibility

    but switching fuels on such a burner might take more than opening/closing valves and throwing a switch. We'll have to look at this more closely.
    "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.
  • Tim McElwain Tim McElwain @ 6:55 PM
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    The nice thing is that

    on Power Flame it is simply a matter of throwing a switch to change from one fuel to the other.
  • livinthesteamdream livinthesteamdream @ 7:00 PM
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    That would be nice!

    I have a contractor friend who was tearing out an oil tank. Consequently, I was fortunate enough to get about 180 gallons of oil for almost half the cost I was paying from the local oil company due to a person who had filled up but then just replaced the system. That kind of flexibility would be nice just in case I ran into another situation like that. It isn't everyday, but it's nice to take advantage of when it does happen.
    twice the boiler I need, short cycling, atrocious near boiler piping, excessive fuel consumption, water hammer throughout...you name it I got it in my system O_o
  • BobC BobC @ 8:21 PM
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    Don't try to store oil

    for much beyond a year. The new heating oil is not stable long term so It should be used up in a reasonable amount of time.

    When I installed the Smith G8 / EZGas boiler I knew I always would have the option of going back to oil if anything happened with natural gas  cost long term. I'd have to buy an oli gun and get a tank but the option is there.

    Bob
    Smith G8-3 with EZ Gas @ 84,200 BTU, Single pipe steam

    Vaporstat with a 12oz cut-out and 4oz cut-in

    3PSI gauge
  • livinthesteamdream livinthesteamdream @ 8:30 PM
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    Unfortunately...

    at a consumption rate of 600 gallons a month, 180 didn't last very long with my boiler. ;)  A year...forgetaboutit! lol
    twice the boiler I need, short cycling, atrocious near boiler piping, excessive fuel consumption, water hammer throughout...you name it I got it in my system O_o
  • Dave in QCA Dave in QCA @ 10:16 AM
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    You could just save the old burner

    I operated a pair of large dual fuel boilers 25 years ago. At that time, the dual fuel option was not set up properly and I set out to make corrections and set it up so that the firing fuel could be changed with the flick of a switch, the way it was supposed to be. At that same time, we changed from firm service gas to interrupt-able, which saved 25,000 a year. These boilers were 238 HP Kewanee Scotch marine type, firing at around 9 Million BTU on high fire.

    Set up and adjustment was a pretty complicated process as the the burners were fully modulating, not a simple hi-low operation. The first step required getting the oil firing correctly adjusted at hi fire, then at the low end of the modulating range. Second step was to adjust the air shutter linkage to provide the correct mixture of air through the full range of oil firing. The third step was to switch to gas and then adjust the gas firing rate to match the air shutter so that proper mixture was obtained all through the firing range.

    While it does not sound too complicated, the process required a considerable amount of time. But, once it was done, fuel switching merely required a few steps to the boiler, turning the boiler off, turning the selector switch to the desired fuel, and turning the operating switch back to "on".

    In your case, a dual fuel burner might be unnecessarily complicated and expensive. You could just save the old burner and of fuel oil prices ever get lower than natural gas, (not likely), you could simply install the old burner and you probably could change the nozzle and make it fire at the lower rate you need.

    As for the option of 1 stage or 2 stage, I would opt for 2-stage, but there will definitely be a price difference. 2-stage firing would provide a benefit if your load varies from time to time because of some of the radiators being turned off and at other times, all of them being turned on. Also, if you frequently fire the system long enough to fully heat the radiators, this will cause the boiler to cycle off and on. This can be minimized in single stage firing by having a low pickup factor. But, if you do this, you will need to make sure that your main venting is good and fast and your radiator venting is slow, for example, no faster than a Hoffman #40. This arrangement will make your system slow to heat up, but it should be even and in most cases, on off cycling when fully heated will be minimized and may not occur at all.

    Gas pipe size: You probably need 1 1/4" if running house pressure from the meter. 1" is too small.
    When we bought our building, the boiler was a 1,050,000 BTU firing rate. We are on low pressure and there is a 2" main coming in from the street. The meter is a 2" meter, but the piping reduces to 1 1/2 to the boiler which is about 40 ft away. This piping was actually a little under sized. In addition to the 2" meter, there are 9 more meters connected to the incoming main, most are for kitchen stoves by 2 of them have forced air furnaces on them. It all works just fine and the pressures are adequate to deliver the required amount of gas.
    Dave in Quad Cities, America
    Weil-McLain 680 with Riello 2-stage burner, December 2012. Firing rate=375MBH Low, 690MBH Hi.
    System = Early Dunham 2-pipe Vacuo-Vapor (inlet and outlet both at bottom of radiators) Traps are Dunham #2 rebuilt w. Barnes-Jones Cage Units, Dunham-Bush 1E, Mepco 1E, and Armstrong TS-2. All valves haveTunstall orifices sized at 8 oz.
    Current connected load EDR= 1,259 sq ft, Original system EDR = 2,100 sq ft Vaporstat, 13 oz cutout, 4 oz cutin - Temp. control Tekmar 279.
    http://grandviewdavenport.com
    This post was edited by an admin on April 16, 2014 10:18 AM.
  • livinthesteamdream livinthesteamdream @ 9:29 PM
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    V908A steam rating

    I just realized (if I'm reading this correctly) that although the V908 produces 2,888 sq ft of steam per the V908 series literature and what was mentioned earlier, my boiler being a V908A model actually produces 3,471 sq ft of steam under the Net I=B=R area effectively making my boiler 2.4 times too big!!
    With this even larger discrepancy in the size it should be and the size it currently is, is a smaller NG burner still gonna work? Additionally, should I buy a burner that is sized to the V908A or one that is sized more to a V904A which puts out 1508 sq ft of steam? I'm still way up in the air as far as the burner is concerned so I'm trying to get an idea on what the burner itself is going to cost as well as what I could possibly get for the CF1400 oil burner if I decided to sell. I'm not asking for prices since that isn't allowed on here. I just need to decide which model would be best suited for my situation.
    Any thoughts gas pros?
    twice the boiler I need, short cycling, atrocious near boiler piping, excessive fuel consumption, water hammer throughout...you name it I got it in my system O_o
  • typical mod burners

    installed on boiler have been at least 3 to 1 downturn, so usually going down to 1/3 input  should be safe.  Check out Burnham's recommended burners and their downturn rate.
    The Steam Whisperer (Formerly Boilerpro)
    Chicago's Steam Heating Expert


    Noisy Radiators are a Cry for Help
  • livinthesteamdream livinthesteamdream @ 10:16 PM
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    Whew...

    I'm glad I'm still within reason despite the size discrepancy. Burnham has numerous recommended gas burners such as the following:
    Beckett CG10.4S, CG10.4S, CG10.5S, CG10.6S, CG15.3S, CG15.4S
    PowerFlame JR30A-10, JR30A-12, or JR30A-15, JR50A-15 
    Plus, there were also gas/oil combination burners they suggested.
    **Stupid question--How do I find the downturn rate?


    twice the boiler I need, short cycling, atrocious near boiler piping, excessive fuel consumption, water hammer throughout...you name it I got it in my system O_o
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