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Steam boiler replacement in order to save system.

Hi there,

The bottom line is I need help big time with this, and I may end up having to do most of the work myself. I had some great help from members on the site last year when my wife and I first bought our first (and last...... seriously) house and I really appreciated everyones input! Then I disappeared from the site for personal reasons and I apologize for that but now I'm back and will be sticking with this. This link is now on my desktop and I'll be checking, updating regularly as I think I'm in it for the long run. Bare with me on this first long post so a decent picture of what's going on can be established.

Previous short thread:

Why I'm posting this is that I've had 4 heating companies come over and two wanted nothing to do with it as they don't get involved in steam and the other two told me to install a hydronic system. One of those gentleman, I've been told by several of tradies I work along side with, was the 'steam guy'. All were nice guys, all companies were fairly small outfits but my gut feeling after 6 months of research on steam and years of working on equipment tell me this just feels wrong. The only thing that they have all said is that steam is less efficient and you won't get the controllability like you do with hot water. Not one of them has said the system was badly designed or put together, in fact quite the opposite, and yet 'go hydronic' and 'mod cons' are the only option I've been given. I read countless threads on steam efficiency so I understand that every situation is different but this efficiency thing I keep being told seems like kind of a sham.

Project: Bought a small 2000 sq/ft school house from the 30's. Pretty much empty for 35 years. Steam system was last fired up in 1990. About 180,000 Btu's of case iron radiators upstairs and 28,000 Btu's in basement (double fins).
Hurricane Irene flooded this house and the entire basement was underwater plus 4 feet on the first floor. River bed silt has been a battle in clean up.

Fast forward. I spend a little time trying to put the boiler/heating system back into operation, just to see what we had as a system, what was not going to be usable and what was junk. In a nut shell, I kind of failed as I ran out of time with winter last year. I had to use the chimney space to run a stainless wood stove liner so now the old oil burning boiler does not have a flue to exhaust into. The exhaust was 14" in diameter so there was only one place for it to go with those high exhaust temps. Plus when I did the math, the current boiler would have bankrupted us if we were to use it normally.

Current Boiler info: Weil Mclain 582 boiler ----- 540,000 BTU's ------ 5.15 GPH OIL

I disassemble and clean nearly all the components you see in and around the furnace. Had to replace a few also which now is basically a waste of money but its wasn't that much. I replaced the bullnose fitting at the bottom of the Hartford loop as there was a 3" crack across it. That bottom leg had some pretty gross sediment corrosion as expected.
With the help from members from thread above about traps, I purchased some 1972 cage unit for the Warren Webster O2H traps.
Rebuilt and tested burner running 4.0 nozzle (down burning). Worked great. Now I have a fun flamethrower with not use.
I no longer have a fuel supply system so anything is optional for fuel

All this was kind of pointless I know, as I never fired up the system and I couldn't get anyone knowledgeable to help me with it even if I was ready.
I can take as many pictures as people like, answer any question I can and do all the heat calculations of radiator capacity again. My question is why is no one telling me to keep the steam, but ripping out the entire buildings piping and starting again with a water system is the only option being given?. Is fitting in a new steam boiler into this piping just too difficult?

Please post comments if you believe I'm on the right track and should work with this, installing a new modern steam boiler and needed components. I appreciate options and ideas, contacts and equipment recommendations. I would have loved to have someone do this for me but I'll also take someone just supervising the build if they new what they were doing but didn't want the job of installation itself. I know I really need a steam pro to set this up properly.

Please chip in if you have any insight to anything above. Thanks for any help offered.


  • neilcneilc Member Posts: 822
    we missing something ?

    find a proper steam contractor,
    where are you located?
  • Danny ScullyDanny Scully Member Posts: 1,264
    I looked through your original post and didn’t see where you were located either. So?
  • Intplm.Intplm. Member Posts: 1,192
    Hello @johnnygreenham . I appreciate that you are on a quest for steam.
    I'm wondering how much damage was caused to the boiler in the hurricane. You say the entire basement was under water with silt damage?
    This might be why the contractors do not want to resurrect your' boiler. Kind of a cost to what level of success concern.
    The boiler may need to be changed and the system up graded but not entirely ripped out.
    What area are you located in?
    You should check the find a contractor section on this sight.
  • neilcneilc Member Posts: 822
    neilc said:

    we missing something ?

    This long post wasn't here a half hour ago , , ,

    something to consider,
    there will be another Irene, and another Sandy,
    Sandy didn't get you also?

    maybe, maybe in this case a wall hung boiler upstairs makes some sense.
  • SteamheadSteamhead Member Posts: 13,998
    Or a big sump pump. Where are you located?
    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.
  • FredFred Member Posts: 8,440
    edited January 2019
    We need a lot more pictures. Some of the radiators and the returns as well. It sounds like you have about 866 EDR of connected radiation (including the basement) and it looks (hard to see) like the boiler is rated at about 1600 to 1700 EDR. Any replacement boiler needs to be way, way smaller than what is there now. Also, 866 EDR for 2000 sq. ft. puzzles me. I have 700 EDR in a 5000 sq. ft. house.
    - How are those basement radiators mounted? Are they on the ceiling above the boiler water line or is that a hot water loop?
    - The current boiler isn't piped correctly and the new boiler should have the risers out of the boiler next to each other, then the risers to the mains following that and the equalizer on the end, after the main risers.
    - That header looks too close to the boiler water line as well.
    - What is that pipe off of the left side of the Header? Is that to a single radiator or to the basement radiators? In any case, it should not be on that end of the header.
    - That same pipe looks like it has been reduced on the horizontal a little downstream of the boiler. If so, that's not good either.
    - Those mains look rather small. What are they? 1.5"?

    If you can salvage the steam system (obviously minus that boiler), that will likely be your best bet. I would think ripping it out and installing a totally new Hot water system will be more costly and won't likely be any more efficient than a properly sized steam boiler and connected radiation but you need a pair of knowledgeable eyes on site.

    Where are you located? Maybe we have someone on this site that we can recommend.
  • Jamie HallJamie Hall Member Posts: 13,418
    Hi Johnny! My recollection is that you are in Vermont (but I don't recall exactly where?)... which is beautiful, but is kind of out in the woods for steam, for some reason.

    I don't see any reason to ditch the steam system as a whole -- but I do see some good reasons to ditch the boiler (sorry about that). Mostly it's having been totally underwater in Irene, and being somewhat elderly -- and thus not as efficient as the newer ones might be.

    It will be easiest in terms of choosing a new boiler to convert those BTU ratings into EDR -- if you don't have the EDR ratings already, dividing by 240 will get you pretty close. Then we can make some suggestions as to what new boilers might suit best.

    You will certainly have to assemble a new header -- the one you have isn't really piped right, and even if it were the odds of it fitting the new boiler are close to zero. That, however, isn't all that hard to do. The new boiler will come with a manual, which will have the manufacturer's minimum piping quite clearly illustrated. If you can find a plumber who is willing to cut and thread pipe, and willing to take some direction, the installation itself isn't that hard (although there are a few odd things to watch out for -- like making sure the water line of the new matches that of the old as to elevation).

    I personally in Vermont would recommend oil as your fuel. LP has its points, surely, but expense isn't one of them at least up your way. Finding a good way to exhaust the boiler may take some ingenuity, though; you may well find that installing a new metal flue is the best way to go on that.

    One further thought on installation: in principle, you could probably do most of it yourself if you have to -- except for one thing: adjusting the new burner for best combustion. For that, you will have to find a heating tech. who has the proper instruments and is willing and able to use them correctly.
    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
  • johnnygreenhamjohnnygreenham Member Posts: 50
    Sorry it was a long post.
    Really appreciate all your comments.
    I’m based in the town on Jay, NY. Just south of the Canadian border in the mountains. If there is someone in the area who is really recommended in my area, I'm all ears!

    To Fred and Jamie, you're not the first to comment on the header piping not being correct. A member called nicholas bonham-carter pointed out some errors with it last year.

    Irene flooded the basement, thats for sure, but most of the entry paths where that water broke in have been blocked. I'm designing a flood door for the back entrance and at that point it will be very difficult for water to gain entry into the building. Its basically a little brick concrete bunker. We now have duel sump sumps just in case.

    I agree the boiler needs to go. I wanted to fire it up to see if the rest of the system worked but I didn't even have a fuel tank or lines to feed it long term. We could never afford to run it. It's over twice the size required, then some.

    The basement radiators are about 18' long on the wall with two sets of fins.

    There is basically three loops.
    One large loop going anti-clockwise (middle valve in pic) if you are looking at the boiler head on. It leaves the risers on a 3.5" pipe (i'll measure and check). Goes through a wall, turns 90 deg and reduces on a horizontal to 3". I'll take a pic of this as it will be way easier than trying to explain any further. This loop supplies 2/3rd's of the ground floor radiators.

    The second loop goes clockwise (right valve in pic). Pipe size is smaller 2.5" I believe (or 3") and supplies the last 1/3rd of ground floor.

    The last loop is the basement fin radiator Fred (left valve in pic)
    It has some crazy small thermostatic valve on it which reduces the pipe to 1/2" then back to 2". This is wrong I'm sure.

    From what I'm understanding, propane may be the only fuel option that will give me exhaust gasses with low enough temperatures that I can vent out of the side of the basement and not require a chimney or stove type piping.

    I will take pictures of the entire system tomorrow, pipe work and all.

    I really appreciate all the help we can get. My wife and I had to move out of the house yesterday and into a garage nearby until the temps rise a little as the house basically froze, 4" sewer line and all. I'm still working on the house every moment I can.

    Will post again tomorrow with photos. Thanks again.
  • AMservicesAMservices Member Posts: 515
    Nobody's telling you to keep steam because not enough heating contractors have taken the time to learn about steam.
    Too many people see a 95% efficient sticker, compared that to the 82% efficient sticker on the steam system and say "that's the end of that".
    The truth of the matter is steam can be as efficient and some would argue, a more comfortable form of heating then any other heating system you could have.
    Combustion efficiency is not the end of the story.
    Overall home heating efficiency comes from more places then the combustion chamber.

    Find the right contractor. Make sure he can read a manual and follow installation instructions.

    Keep steam
  • SeanBeansSeanBeans Member Posts: 483
    Crazy that Irene affected you all the way up there! The amount of water Irene brought here in NJ was pretty wild...
  • Jamie HallJamie Hall Member Posts: 13,418
    SeanBeans said:

    Crazy that Irene affected you all the way up there! The amount of water Irene brought here in NJ was pretty wild...

    Ah @SeanBeans -- you should have seen Vermont. Roads and railroads washed out pretty much everywhere in the state. A real catastrophe -- and in some places they are still repairing from it.
    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
  • GrallertGrallert Member Posts: 454
    It doesn't look like that system is so far gone to me. I've seem worse that are running. It sounds like you have a handle on the steam operation side of things, Seems to me you need three things for the time being. You need a flue. You need steam trap capsules Right? You need to install the burner and gasket. Not sure if you have a fuel tank? You likely need to rebuild the combustion chamber is it got really soaked. after that you need to check all the safeties and the combustion. I guess that's more than three things. This time of year is a bad time to dig into it though. I wonder if the boiler holds water? You could buy a lot of time if you got that old genny up and running.
  • johnnygreenhamjohnnygreenham Member Posts: 50
    edited January 2019
    The flue issue is the biggest challenge to me if I was to try and get the old boiler working. The pressure switch also has a small issue in that it operated correctly but if the mercury switch trips, the reset doesn't want to reset it. It's something to do with that tiny spring in the back of the unit and the lever but I really don't think I will be firing this unit up unless absolutely necessary.

    For the flue I have no options apart from that chimney for a 14" pipe unless I vented it out of the coal bunker door for test purposes which would cost me a bit of money just to set up. I will be turning the coal shoot entrance into where pipes and exhausts will enter/exit the building but it exits at just above ground level at the side of the building, so work needs to be done to pass local codes etc.
    The building is mostly metal lath walls and concrete, attached to a wood frame, then a brick and stone building on the outside. It was a DWP project and they went on the over engineered side on pretty much everything which is interest and in most aspects is a positive thing for longevity but having to get through some of the layers can be challenge. The basement is poured bridge concrete with metal mesh and I've smoked several masonry attachments cutting through it, even with water. Thats why trying to get more pipes through the walls for hydronic system seems like it will be difficult and expensive.

    As promised I've taken some more pictures of the system and will try to describe explain anything you have a question about. I will just post them all at the end of this post.

    I feel way better in my gut about keeping the steam and replacing the boiler and that's the way I want to go.
    I'm sure I need to do a few things first so please give me your input in what I need to figure out before I start buying boilers and components.

    #1 should I pressure test the system with air. Water won't be available until spring as I had several semi-frozen lines last week and had to drain the entire system until warmer weather hits.
    If so I will need help, where to separate the pipe work for this.

    #2 I guess I need to double and triple check my numbers for radiator EDR figures. would someone mind posting a link to a page with the formula required and a chart for tube ratings/size etc that is correct.

    #3 What else should I be doing before I start dismantling the boiler to get it out and what parts will/can I reuse in the system you see.

    P.S I just wanted to confirm that I'm pretty confident in installations of many kinds as long as I have good literature, drawings and schematics so I think I can do this if I can not find a professional steam guy locally who wants to keep the system and lead the way. I will absolutely have someone check over the entire install and have them set it up correctly even if I have to call them in from Albany.

    I also don't have any means of hot water tank etc so need to consider that when choosing a boiler.

    Thanks everyone for the help again.

  • Jamie HallJamie Hall Member Posts: 13,418
    Actually doesn't look too bad. But -- you've got me real puzzled on one thing, and hopefully someone else will enlighten me. Is the silver gadget on a reduced line between two lines a vent? And are those dry returns?
    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
  • JUGHNEJUGHNE Member Posts: 7,203
    I wonder if that isn't a control regulating orifice for the basement rads or in effect a pipe radiator
    Reminds one of a pressure regulating valve for refrigeration use.
  • FredFred Member Posts: 8,440
    @johnnygreenham , The things that stand out to me are:
    - 4th picture, that 1/2" or 3/4" thermostatic valve, not sure why it was installed but the 3" main has to be holding water there and it should be removed.
    - 8th picture, that reduction on the horizontal needs a drip, dropping to a wet return to get the water out of the larger pipe.
    - 10th picture, that fin tube, are they above the boiler water line? That will be a problem if not and that may need to be changed to a hot water loop off of the new boiler if they are below the water line and you intend to keep them.

    Over all, it looks like there is a lot there to work with, except the boiler. Way too big and old to put money into it.
    Do double check the Radiator EDR total it seems really high for a 2000 Sq. Ft. building, and it would take a lot of those radiators in your last picture to total 866 EDR.
  • johnnygreenhamjohnnygreenham Member Posts: 50
    That silver gadget is a thermostatic valve. It has an oil filled capillary tube which is attached to a manual thermostat. I’m guessing as temp rises in the room, the oil expands inside the tube and closes the valve. Seems like it reduces the pipe work considerably which I can’t emaigine is ideal.
  • Jamie HallJamie Hall Member Posts: 13,418

    That silver gadget is a thermostatic valve. It has an oil filled capillary tube which is attached to a manual thermostat. I’m guessing as temp rises in the room, the oil expands inside the tube and closes the valve. Seems like it reduces the pipe work considerably which I can’t emaigine is ideal.

    It's got to go. Nice idea, but it won't help the system in the long run.
    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
  • coelcanthcoelcanth Member Posts: 89
    i'm trying to understand the flue issues..

    you can't vent out of the original chimney because you're venting a new woodstove you have added ?

    would it be possible to vent an oil burner and the woodstove through the same chimney ?
  • KC_JonesKC_Jones Member Posts: 4,424
    > @coelcanth said:
    > i'm trying to understand the flue issues..
    > you can't vent out of the original chimney because you're venting a new woodstove you have added ?
    > would it be possible to vent an oil burner and the woodstove through the same chimney ?

    I’m confused here as well. What does the 14” comment reference? What’s on the boiler or what’s in the chimney?
    2014 Weil Mclain EG-40
    EcoSteam ES-20 Advanced Boiler Control
    Boiler pictures updated 2/21/15
  • ethicalpaulethicalpaul Member Posts: 1,867
    I call this "The Water Injector"

    1 pipe Peerless 63-03L in Cedar Grove, NJ, coal > oil > NG
  • johnnygreenhamjohnnygreenham Member Posts: 50
    Unless I got it wrong, I'll try and explain what issue I have with the the flue.
    The boiler you see uses a 14" flue. It used to tap into the wall just behind and vent up the ceramic lined chimney. the chimney was dedicated for that boiler. No other heat source in the building. When we bought the house, the previous contractor had punched a hole on the ground floor and tapped into the chimney for a huge wood stove in our living room. The draw was all wrong for the stove and it would always backdraft or have very little draw. Plus this isn't code standard round here anyway. You can't vent wood and oil/gas exhaust in the same flue raceway. I installed a stainless chimney liner up the the top of the chimney for the wood stove only and blocked off the hole in basement where the boiler pipe entered. You can see a cement plate in one of the pictures.
    The flue is 12" x 18 3/4 Inside diameter. I used a 8" sized stove pipe and liner for the wood stove. There is no room left in the chimney raceway for another liner, also there needs to be certain spaces in-between liners for code again. In a nut shell the chimney space is only good for either the wood stove or the boiler. I would have to install another chimney of some sort to be able to use both through the roof.

    The new boiler could vent out of the side of the building through the coal door but I guess flue gas temps come into play. Thats why propane seems like maybe the only option due to low gas temps. I have heard of a power vent which could maybe be used in another fuel source but I'm not familiar enough about them to comment.

    Let me know if I have this wrong.
  • johnnygreenhamjohnnygreenham Member Posts: 50
    "You have it backwards. Use the chimney for the boiler and do something else for the stove."
    @Steamhead : That may be a little costly at this point. I hear you, and would probably do this if there was really no other reasonable options. I feel venting through the nearby coal shoot (which I will brick up correctly) is doable and would be fine but It limits me to propane fuel which I'm fine with I guess. My ideal burning fuel would be wood pellets round here but I didn't find much in the modern steam boiler world with that fuel source.

    @ FRED: The fin tube radiator is about 18ft long and definitely below the boiler water line. The middle of the pipes for the fin tube heater are 18.5" and 24" from the floor and the boiler water line (center of sight glass) is 57" from floor. The drain pitches down and re-enters system a foot of so above from the bottom part of the Hartford loop. This is where my steam knowledge is a little shaky but it always seemed odd to me when I first saw this. The wet return has been capped off so that loop is no longer in service (once upon a time it was though) but I always wondered what would stop the condensing water from the rest of the system flowing back up through this line all the way up to the trap at the radiator? Nothing I guess

    So trying to go slowly forward, what would be the first few things I should start to do/figure out to line myself up to install a new boiler this spring?
    P.S I'm still game to hire a real steam guy if anyone knows one in my area.

    Thanks again,

  • FredFred Member Posts: 8,440
    @EBEBRATT-Ed , @JohnNY @Danny Scully , Do any of you guys cover Jay, NY?
    @johnnygreenham , I suspected that fin tube radiator in the basement was below the boiler water line. I then thought it might have been a hot water loop but I saw a trap on it so I doubt that that ever heated anything set up the way it is, unless the guts have been removed from the trap and they just let return water run through that radiator, on it way back to the boiler, to take advantage of any residual heat in the water. Wouldn't have been much but someone may have decided to experiment. It wouldn't take a lot to make it a hot water loop if you need heat in the basement.
  • JohnNYJohnNY Member Posts: 2,497
    I don't cover it as a contractor but I would go there to consult since it's a 5-hour drive each way for me. But I would go...and with my earnings I would visit Montreal. And I would take lovely pictures and eat French Canadian food.
    Just saying.
    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.
    For residential service and installations in New Jersey, please see Toro Plumbing & Mechanical and fill out our contacts page, upload pics, and submit, or call (973-672-1000).
    Erin Holohan Haskelladasilva
  • Danny ScullyDanny Scully Member Posts: 1,264
    I’ll jump in on that ride @JohnNY :sunglasses:
    Erin Holohan Haskell
  • AMservicesAMservices Member Posts: 515
    @johnnygreenham You said you had 208k BTU output of cast and fin tube. How did you get that number?
    Really important to get that number right to pick the right boiler.
    Maybe you can share a list of radiators and how many feet of fin tube you have connected (and disconnected that you plane on reconnecting to the system.
    After you know what boiler your going to use, then you can start thinking about how your going to vent it.
    I recommend using the chimney for the boiler and vent the wood stove through the wall, if possible.
    Boiler takes priority because it heats the whole house and DHW if you choose.
    I only like power vents when the chimney is not in any way an option. They can be loud and just another device that can fail.

    Behind the boiler, on the right, there's a cement pad that looks like a water heater could have been there.
    Is that a gas line that drops down to it? And are those hot and cold water lines capped off above it?
  • johnnygreenhamjohnnygreenham Member Posts: 50
    edited January 2019
    Thanks for the offer John. It's an option which I'd like to keep on the table. Appreciate it.

    @AMservices. That number was something I calculated a long time ago but I had trouble as I was using a funky chart. Wish I could still find all my notes.
    I started calculating the EDR value yesterday and surprisingly came up with a very different number so maybe someone could check if I've using the correct chart.

    Here is the link.

    I identified my radiators as thin tube radiators.
    Mostly using vales 1.3 and 1.7

    I got this figure by measuring the height of each radiator and then measuring the thickness (width).
    Once I had that figure, I multiplied it by how many sections per radiator.

    Last time I tried this I worked out everything using a BTU's chart which apparently I may have gotten confused on if this EDR calculation is correct.

    I have 14 radiators not including the fin tube one downstairs.
    It worked out to have 402.2 Square feet of radiation.

    402.2 x 240 = 96,528 BTU's

    Here are some pictures of the three types of radiators I have (last two pics are the same type). I know most are not floor mounted but I figured the foot thing was not that important for using the chart above.

    I found a page in my note book that the basement fin heater was about 1300 Btu's per foot of heater.
    At 18ft thats 23,400 BTU's
    23,400/240 = 97.5 EDR
    From what you are all teaching me on the site, this fin radiator will be hot water and not steam as we go forward. Curious if that 1300 per foot value is correct?
  • FredFred Member Posts: 8,440
    I'm sure 1300 BTU's per foot isn't correct. That would be about 5.5 EDR per foot. or 95 EDR for that 18 ft pipe. The EDR or 240 BTU's is based on a Sq. Ft of steam, not linear foot of pipe. You need to figure out how many feet of pipe, that diameter, it takes to give you a Sq. Ft. In any case, for hot water, a sq. ft. of hot water is 185 BTU, not 240.
    The 402 EDR for a 2000 sq. ft building seems much more plausible that your original numbers.
  • JUGHNEJUGHNE Member Posts: 7,203
    I work on at least 4 school buildings with steam heat.
    No one should have ever got cold. These were seriously over the top with radiators.
    The oldest from 1919 had outside air louvers behind most CI rad. Even store rooms had their own radiator.
    The huge windows in this building were there for lighting as there was no electricity. (Even when new provided plenty of fresh air).
    This sizing was probably caused by the flu pandemic of the previous years.
    Then the 1933 & 1938 buildings followed this design with EDR's and windows.
    The 1955 school had the large windows with forced exhaust ventilation.
    After envelope improvements all now have a boiler that is twice of what is needed.

    So with your school house, IIWM, I would do a room by room heat loss calculation.
    Use the original radiation units but limit the EDR output with orifice metering on the supply valves. Say perhaps to 60-70% of the actual EDR, if that is what the actual loss is.
    Then IMO you could size your new boiler on that 60-70% of connected EDR. You still need some pick up factor though.
    That 30-40% of radiator would never get hot.
    In my mind that cool iron would just be part of the return piping.
    No traps would be needed. The condensate would be actually almost cool returning to the boiler.
    An orifice costs about only 20% of a replace trap element and never wears out.
    You must keep the pressure within your design limits for orifice sizing. You can always drill the orifice larger if needed.
    There is some discussion just a week ago here about this method.

    Your fin tube, what size of pipe, the size of the fins, and spacing?
    They look like some I have in one of these schools.
  • coelcanthcoelcanth Member Posts: 89
    looks like a nice building and a nice system.. it'd be great to get it running again..
  • FredFred Member Posts: 8,440
    @johnnygreenham , The numbers you used to calculate the EDR compare well to a chart I have. I wouldn't convert the EDR to BTU's. Just match the total radiator EDR to the Sq. Ft. of Steam on the boiler plate. If you insist on using BTU's, add another 33% to the total BTU's for piping and Pick-up factors.
    If you use the EDR to SQ. Ft. of steam, don't add anything to that as the Manufacturer has already factored that into their net Sq. Ft. of steam. So, look for a boiler that is somewhere around 402 Sq. Ft. of steam.
  • Jamie HallJamie Hall Member Posts: 13,418
    Off topic history -- a lot of the old schools in Vermont had cold temperature ventilation -- a big steam convector in the bottom of what was essentially a chimney, drawing air from two adjacent classrooms. Silent and worked a treat. Then the Arab oil embargo hit (remember that?) and everyone went around sealing up those great big chimneys. Saved a lot of oil, but... no ventilation any more to speak of. In those days, Vermont was mostly farmers (now it's mostly millennials... sigh...) and the farmers' kids did the chores (read: mucked out the barns) before school. The results were interesting...
    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
  • johnnygreenhamjohnnygreenham Member Posts: 50
    edited January 2019
    @Jamie Hall. Thats funny you say that. We have those chimneys, well, more like huge square duct work in both the classrooms. We only have two large rooms.......its a small school. There also used to be two large open grated vents on the other side of the rooms that were open to the outside permanently. I glass blocked them up as thats where Irene came gushing in......well that and the front door/basement windows. From the holes in the floor there must have been some sort of steam heat exchanger in front of those fresh air entrances. Two chains in the middle of the building, use a pully system in the attic to open and close louver doors in the duct work. The ductwork vests out of the very top of the building via a copola. It's a huge nature air circulator. Quiet ingenious really, when fuel was cheap.

    @Fred : I'm more than happy to just use EDR rating from now on. I will take some measurements over the weekend of the fin distances and size with pipe sizes and try and nail that down. At that point I have my values.

    @JUGHNE Thanks for the post and really interesting that you most likely look after schools that have the same designs as ours, huge windows etc. The room heat loss calculation is a little daunting to me and that value will change massively with certain improvements we will make this summer but I always seem to go slightly different direction after too much research on things like attic insulation etc. So I'd hate to base the boiler size on something I'm meaning to do but may end up not doing? May be worth it just for more information I guess. I'll post back with the fin heater info this weekend.

    I believe I may have found another contractor I know who used to work in Brooklyn, who may be able to work with me in the piping part. He used to cut and thread pipe a lot for steam projects in the city but he has been very clear that we would need someone to overlook the project and set up the system once installed. He still has all the pipe threaders, string, paste etc even though he just builds houses up here now. We would need good plans and drawings of the new piping but its a start in saving this system, which is a change from banging my head agains a wall.

    Please keep the info pouring in.
  • Steve MinnichSteve Minnich Member Posts: 2,584
    I love mod cons but there's no way I'd propose one for a system that can be salvaged rather easily, and your's can. Get out the PB blaster and some big wrenches and go to work. Use the wood stove until you're done and then, like @Steamhead said, dedicate the stack to the new boiler.
    Author - Hard Knocks: My Life Inside Boiler Rooms
    PHC News Columnist
    Minnich Hydronic Consulting & Design, LLC
  • johnnygreenhamjohnnygreenham Member Posts: 50
    @Steve Minnich . Appreciate the positive feedback. I would not undertake this is if felt I could not do a professional installation. Design, choosing the correct components, knowing why I'm installing the system I am and it's configuration and final set up are what I need coaching with. These are why you hire a steam pro right. But for the first time in a while I feel like I'm making forward progress. I guess by the end of this I will know exactly how to take care of it and how steam acts which is pretty interesting.

    @JUGHNE @Fred . The fin tube radiator dimensions/specs are:

    Individual fin size is 4.25" x 4.25".
    Approximately 17 feet in length of fins on each row.
    two rows = 34 feet of fins
    Spaces 1/3" apart.
    Pipe going through fin system is 1.5".
    Approx 18ft for one length of 1.5" (x2)
    Total 36ft of 1.5" pipe

    I've had a little look on the net but couldn't find any value for this style of radiator?

    I have a quick question also. I've read a bit about the importance of water level in boilers and when replacing an old boiler, it seems to be imperative to measure the old water level and match it with the new boiler, but this seems confusing to me. This boiler is physically larger than the new one will be considerably smaller. Not really an issue but the distance from the water level to where the risers meet the manifold currently seem to be too short, for what the minimum is recommended ignorer the create dry steam. I understand that the boiler level is important in relation to the Hartford loop and the piping around it (maybe other aspects also) but surely I will need to establish my desired water level to the risers etc, for my new system and re-pipe everything accordingly. So does this mean that my currently water level is not really important.
    Is this question clear as mud?
  • FredFred Member Posts: 8,440
    @johnnygreenham, The important things to remember when installing the new boiler is that:
    - the Header (horizontal pipe above the boiler) be at least 24" above the boiler's normal (idle) water line.
    - That the manufacturer's specs will tell you what the normal water line should be (in inches above the floor or bottom of the boiler cabinet)
    - That anything that is below the normal water line now, wet returns, hot water loops, and Hartford loop must stay below the water line of the new boiler. If you cannot retain those wet loops, you will either have to re-pipe them to keep them below the new boiler's water line or raise the boiler on a poured slab or concrete blocks so that that piping remains below the water line. and that you still have the 24" minimum from the water line to the header. More height to the header or a Drop Header is even better for dryer steam..
  • johnnygreenhamjohnnygreenham Member Posts: 50
    edited February 2019
    @Fred Thanks Fred. Thats roughly what I understood. The 24" rule I had jotted down. I believe from the bottom of the header to the middle of the sight glass (assuming thats water line), is currently 16". I will check when I back home tonight. I don't need to replicate a not ideal configuration.
    Until I purchase a boiler, I guess I have no idea what size pipe the new unit will need/accept or where the pipe entrance/exists are located distance wise so maybe my piping is all too big and at the wrong levels which is most likely, so I will have to remove enough piping in order to repipe correctly.
    I'm understanding that all reducers should be on the vertical, so not to trap/pool liquid, correct?
    The Wet return probably doesn't matter what size it is or where the reducers are located, just the importance in relation to the water line is imperative .

    @Fred I would really like to understand exactly why the current head configuration isn't correct. I'm trying to wrap my head around it. Several people have pointed it out, but you seem to have tried to explain it above, but I'm not quite following why it makes a difference compared to way you say it should be. Sorry, probably steam 101. I might be misunderstanding your terminology of system part names.

    From yourself......."The current boiler isn't piped correctly and the new boiler should have the risers out of the boiler next to each other, then the risers to the mains following that and the equalizer on the end, after the main risers"

  • FredFred Member Posts: 8,440
    @johnnygreenham , first, don't down size any piping that you don't need to. Big headers and risers are always better than ones that are to small. The sizes and configurations suggested in the installation manuals are always "minimum" requirements.
    - Even though your header is too close to the water line, there is plenty room to reduce the length of the risers from the header to the mains to get the headroom you will need.
    - Yes, any pipe reductions must occur on the vertical. Never on the horizontal.
    - The problem with the way your header is piped (aside from being to low to the water line) is that your risers out of the boiler are at opposite ends of the header, with the risers to the mains in the middle. When the boiler makes steam, that steam coming from each end will collide in the middle of the header trying to get to the mains. That's not good as it with cause the water droplets to pool in the middle of the header and there will also be resistance for the water to flow properly back down the equalizer at the end of the header. The correct configuration should be: Riser out of the boiler into header, 2nd riser out of the boiler, into header, Riser to main, riser to main, riser to main, and equalizer at the end of the header, opposite the risers out of the boiler. Use swing joints meaning do not pipe the risers out of the boiler directly into the bottom of the header. Pipe it from the side (like your current one is). That will allow elbows and nipples to swing as the header expands and contracts minimizing any stress on the boiler sections.
    - You can reduce your wet returns on the horizontal, if you need to but keep in mind you want those wet returns to be large enough to handle the volume of condensate and to not easily clog. You also want to minimize locations where clogging can occur.
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