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Steam boiler replacement in order to save system.



  • johnnygreenhamjohnnygreenham Member Posts: 41
    edited May 2019
    Possibly..... but I will say this is a guy I approached, through a friend I have in town who works in the construction industry. This steam guy is kind of going out of his way to work all this out for us as we are not the ideal situation where he could drive over and see it for himself. I'm sure we are chump change to him in terms of products he can sell us. The reality may be that running steam in this house will always require a 3.5 GPH boiler which probably means my wife and I would be eating baked beans for the winter.
  • SteamheadSteamhead Member Posts: 13,815
    @johnnygreenham , you need someone who will actually come to the site to look at it. It can't be done by remote control. @JohnNY and @Danny Scully said they'd come up there in earlier posts...............
    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.
  • johnnygreenhamjohnnygreenham Member Posts: 41
    OK. I'll reach out. Thanks
  • KC_JonesKC_Jones Member Posts: 4,410
    With an EDR of 402, no way you are even close to a commercial boiler. He might be a nice guy, but a majority of what you typed is incorrect information from him.
    2014 Weil Mclain EG-40
    EcoSteam ES-20 Advanced Boiler Control
    Boiler pictures updated 2/21/15
  • johnnygreenhamjohnnygreenham Member Posts: 41
    edited May 2019
    I do hear what you are saying, that's why I'm reaching out again as I feel something is off in the calculation. I definitely was getting a little confused due to him speaking out loud with numbers as he was crunching his calculations, so there is a good chance I have some of the terminology/implementation wrong. The 'coil' at 50,000 BTU's may have been the coil for a water line in the attic he talked about putting in which would be part of a duct work system to heat, reuse and move air around the building. The tall ceilings were in his calculation and this was a way to try and save some of the hot air already made. My understand was that, this would only be part of the system if we went hydronic. Thats why i scribbled down 50,000 BTU's for coil meaning for domestic water in the boiler itself. He was talking sq/ft of steam and numbers that I wasn't recognizing so I'd hate to throw anyone under the bus because I could not follow the conversation quick enough. Either way the take away was that we would be in the commercial boiler range and he strongly recommended go hydronic due to unit cost and running cost. That I'm positive on. I'd still like to stress that this guy has gone out of his way to help us, I just want to make sure he's right with the info I've given him.
  • johnnygreenhamjohnnygreenham Member Posts: 41
    If I could get down to knowing confidently what correct size boiler will work in this system with a domestic hot water coil that can supply enough hot water for the basement tube radiator, domestic hot water tank and roughly what the running costs are of that system in oil then I'd be in a position to finally make the call. But that is the unicorn of an answer right now..........
  • Jamie HallJamie Hall Member Posts: 12,845
    You have a problem, @johnnygreenham , good buddy -- you've got hooked by a super nice steam guy who doesn't know what he's talking about. May I most humbly suggest you talk to @JohnNY (John Cataneo) instead?

    Your system is about a third the size of the one Cedric powers. Your pipe sizes are ample. You don't need to add in the BTU for the hot water system in the basement; you do need to insulate the steam pipes to get rid of that BTU load. You need a nice boiler with an EDR rating of around 400 square feet, and a competent chap to install it. You'll burn perhaps 3/4 of a gallon per hour on oil to fire it, which is what it would take for hot water as well.

    Please do yourself a favour and find a competent steam person -- like @JohnNY (I think, but I'm not sure, that @EzzyT or @Dave0176 work in New York, too) -- and get the system properly done.
    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: 41
    edited May 2019
    @Jamie Hall Thanks Jamie for the advice. I sent @JohnNY an email this morning but I understand we are far away so for most people thats a deal killer. I get it but I'll await for a response/guidance.

    @Steamhead @KC_Jones Appreciate the posts.
  • BobCBobC Member Posts: 5,106
    Boilers are sized by the system EDR, manufacturers state the EDR rating of their boilers so installers can select the best fit. The manufacturers edr rating includes a hidden 33% pickup factor to cover piping and other losses.

    This means a boiler rated at 400 EDR has a hidden ability to handle 133 sq ft of piping and other losses - in addition to the 400 EDR rating . All that piping in the basement should have 1" rigid fiberglass insulation on it so it's EDR will be considerably less.

    You can use that "hidden" EDR to help support the hot water loop because good insulation will cut the pipe losses drastically. Get another quote because I think he may be quoting you a much larger system than you need. In any case wait for the pro's to weigh in on this, I'm sure they will have something to say.

    Smith G8-3 with EZ Gas @ 90,000 BTU, Single pipe steam
    Vaporstat with a 12oz cut-out and 4oz cut-in
    3PSI gauge
  • johnnygreenhamjohnnygreenham Member Posts: 41
    edited July 2019
    Thank you for all the help you have all given us on this project. We have been busy preparing.

    I finally removed the old boiler after a few nights of hard work.

    I should have the last quotes coming in for the megasteam MST396 in the next day or two and was hoping to order the boiler Friday or Monday but I just hit a dump right before we order.

    The question relates to whether or not we need the model WITH the tankless coil or not. I was always thinking we would need it but I'm now thinking not. ???
    We will in effect be running two hot water zones from the boiler and it seems crazy to me to run it through a small heat exchanger (tankless coil) when we have already heated the large volume of water in the boiler itself.

    Our zoning will be this:

    Zone 1 - will be to the basement fin tube radiator which will be below the boiler water line. (pressure tank maybe required to bleed?)

    Zone 2 - Will be a small loop to the indirect water heater.

    There will need to be some controls/valving involved to allow only the hot water heater to be supplied in summer etc but could someone chime in and explain why I would have to get a tankless coil for what I'm trying to achieve or I am understanding this correctly? Is it bad practice to pipe the boiler water around the basement into the radiator and back or maybe inefficient?

    I have attached a diagram that I added to from this site? Please let me know what you see wrong.

    The 1. and 2. symbols on the diagram was my question to where on a boiler if you don't have a tankless coil, do you pipe off from and how many ports/tappings do you usually get?

    Thank you for any help.

  • JUGHNEJUGHNE Member Posts: 6,894
    Looking at your dry returns....each should drop independently down to the wet return at the boiler.
    As you have them now with a single air vent, the shorter/quicker steam main will close the air vent and the longer/slower main will not get the air vented.
    Each should have its own air venting system and be separate returns isolated by the trap water in the wet return.
    Air vents should be after the last steam take off.
  • AMservicesAMservices Member Posts: 490
    edited July 2019
    This is a 2 pipe system. All the dry returns tie together above the water line and vent through a single LARGE vent.
    You balance the steam entering the radiators with the supply valves or orifices, in the attempt to have all the steam condensing in the radiator and out of the dry return.
    If steam makes it's way to the return on the radiator, a steam trap should be in place to prevent it from entering the dry return.
    What should change about the air vent is its location and its size.
    It would be better positioned on the horizontal pipe, 10 or more inches away from the 90° fitting that points down.
    That 1 vent needs to vent all the air from the system, so make it a big 1 or 2 or 3.
  • Jamie HallJamie Hall Member Posts: 12,845
    I'm with @AMservices on this one. The dry returns in a two pipe system can be -- and often are -- hooked together, above the water line, at the boiler. They should have a single vent or vent cluster at that location -- and nowhere else. Indeed, in most if not all, vapour systems, they have to be for the things to work properly.

    The confusion comes in when one is looking at a pipe which is actually a continuation of a steam main back to the boiler. This is often done for parallel flow, single pipe systems, as a convenient way to get condensate back to the boiler without floor level wet returns. Common enough in single pipe systems. In those, as @JUGHNE says, they do need to be separately vented and separately dropped. But... they are not dry returns. They are extensions of a steam main, and need to be treated as such. The individual vent or vents on each one can be located anywhere handy after the last radiator takeoff.
    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: 6,894
    So are the ends of the mains loop dripped or have an F&T trap?
  • johnnygreenhamjohnnygreenham Member Posts: 41
    edited July 2019
    Good to know about the main vent. Adding another main vent on the horizontal should not be that difficult. Thanks for the tip.

    The ends of the main loops in this system just have thermostatic traps only. No F&T trap. I noticed this and wondered if I could even fit one in due to the limited height different and space between the mains and the return. I'm assuming this was the initial installation back in the 30's but can't be sure.
    I was also throwing caution to the wind and assuming that the system used to function correctly so this probably isn't an issue I would need to improve right away but I'm sure someone can educate me on that.

    P.S I've not removed the trap cover yet so can not confirm if it even has a cartridge inside. All the rest of the traps on the radiators were empty.

    I know there are probably many ways to achieve the same end goal, with some paths more successful than others......
    Did my above diagram of the water zone loops make any sense. I'm just trying to figure out if I should get a tankless coil in the boiler for hot water zoning or if it's now more efficient and a better practice to use the boilers hot water to feed the indirect heater and single basement radiator by pumps/valves etc with no in-boiler tankless coil needed? This is my biggest question mark right now stopping me ordering the boiler.

    Thanks for any advice
  • AMservicesAMservices Member Posts: 490
    Megasteam installation manual Page 29 shows how Burnham has indirect tank piped without tankless coil.

    It dosen't show the bypass loop, but that's the better way to pipe it so you can control the temperature of the water going through the pump and hot water loops.

    I installed a megasteam with another plumber and he suggested we put the pump on the return line back to the boiler so the pump dosen't get hit with steam. Works good, never had a problem. If I could go back, I would have done somethings differently, like make the steam header larger.

    In regards to steam traps and crossover traps.
    You definitely want to replace the cartridges in the crossover traps. If you dont mind the trial and error process to throttle the steam entering the radiators, orifice plates or new supply valves will help keeping steam out of the returns. So you can avoid replacing traps on radiators.
    I would install new traps for extra protection in the event the pressure gets a little high or theres a very long heat cycle.
  • JUGHNEJUGHNE Member Posts: 6,894
    edited July 2019
    I stand corrected on the venting piping, thinking of single pipe EOM.
    Looking at the top picture of EOM trap, it seems the main would collect water as the trap looks to be concentric to the main steam pipe. So air/steam would have to push thru some water perhaps with hammering to get thru the trap.
    Then when the element cools enough to open, some pressure is needed to lift the condensate uphill to the return.
    This looks to be Dead Man original...….one wonders how well it worked.....??
    Is this in a crawl space?
  • johnnygreenhamjohnnygreenham Member Posts: 41
    @JUGHNE. They are both in the unfinished dirt floor section of the basement but I have about 5-8ft worth of height to work in at both ends of the mains. I have to think I will need to re-work those traps but until we make steam I think I will leave it and see what results we get. If nothing, just out of interest.

    @AMservices Thanks for the info and the photos. Those installs are very nice. I will do my best to try and match the quality of the installs. Are blank orifice plates available to but or is it something you just have to make?

    Hot water zones - So I think I will save the money and not get the coil in boiler. I can always add a stand alone heat exchanger if for some reason I feel like I would need one. Maybe the large radiator and length of piping will suck up too much heat out of the water in the boiler if its trying to make steam at the same time but I'm sure I can run some controls to priorities if this happens to be the issue. There are always option right!

    Appreciate all the responses as always.
  • JUGHNEJUGHNE Member Posts: 6,894
    I have gotten blank orifice plates thru Tunstall.
    I have them pre drilled to 1/8", serves as pilot hole for drilling them to size as needed. I hold them in a union with a nipple for a handle as I drill.
    Had a few not drilled as sometimes 1/8 is too large.
  • Jamie HallJamie Hall Member Posts: 12,845
    Those are crossover traps in your picture. A slightly unusual way to pipe them, but that's wat they are. Just make sure that they are working. Then put all your main venting at the boiler, where the dry returns come together before they drop to the wet return.

    I'm going to go out on a limb here and bet that this was once a vapour system. It's beginning to look like that. Due to the slightly unusual piping configuration of your crossovers, you will need to set the cutin on the vapourstat to around 3 ounces per square inch (that's ounces!) so on most vapourstats you would want the cutout (main scale) at around 8 ounces and the differential around 5; if you have a Hoffman Differential Loop on there (you don't say), it should be 7 and 4, respectively.
    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: 41
    edited July 2019
    @Jamie Hall , @JUGHNE : Oh boy, I started to read the lost art of steam again and I'm feeling a little shaky on what I'm understanding.
    I think you are correct Jamie about this once being a vapor system but at some point the original boiler was replaced with the oil boiler I just removed. That probably explains why the basement radiator set up below the water line wouldn't have worked well with that last boiler and thermostat valve. If I'm understanding correctly, there must have been some extra piping/components involved like a Hoffman Differential loop which were removed possibly when the last boiler was installed.
    In a nut shell, you are saying that when this system was first installed, it probably was a slightly different operating system than what we have now? It seems like we can't still be dealing with a vapor system as it doesn't have any of the fundamental components required. I guess it doesn't really have the components (F&T) for a regular two pipe system either?

    What we still have in system
    1)What we have left is two Steam mains, each having a crossover thermostatic trap at the end.
    2)Two pipe radiators with Thermostatic traps on return dry legs but they were all empty (no cartridges)
    3)A third main but this dips under the water line of the previous boiler so the entire piping/radiator is wet apart from the pipe that connected to the header.
    4) One main vent on dry return located on the vertical above water line.

    What we don't have in system
    No F&T anyware
    No Hoffman Differential loop
    No Boiler
    No Hartford Loop

    I was literally about to order the boiler when I read your post so I'm going to hang off ordering for another day or two until I make sure I understand what needs to be done or what I have to do to my piping to make it function properly with a new boiler and changing what was the 3rd main to water (to basement radiator).

    I think I need to post more drawing and photos/video so maybe you guys can confirm what I need to add to get this new boiler working correctly. as it stands I don't think it will operate correctly if I just installed a boiler. Am I wrong?

    Update: Here are three short videos of our entire system with from below except the radiators above the floor.

    First: Main loop #1 Larger

    second: Main loop #2 Smaller

    Third: Was third main with radiator running from condensate, but if possible will turn into separate hot water loop
  • johnnygreenhamjohnnygreenham Member Posts: 41
    I'm reading as much about Vapor systems as possible. I would be very inclined to just return the system as was initial installed back when there was the original coal boiler but the main issue I see is that we no longer have the Hoffman Differential loop and I'm sure no one makes or sells that main component anymore.

    What do you believe is my best option with what we have to work with here?
  • AMservicesAMservices Member Posts: 490
    What Jamie and jughne said dosen't change the boiler.
    What Jamie is recommending is that you get a vapor stat pressure control. Its identical to the pressuretrol that comes with the boiler. The difference is the scale is in ounces not pounds of pressure.
    You dont need differential loops or any contraptions associated with the dead men's vapor systems.
    What defines a vapor steam system, is the ability to heat all of the radiators with less then 16 oz of pressure.
    The Hartford loop is just the configuration of piping the return condensate back to the boiler. Chapter 5 LAOSH.
    You don't need F & T traps.
    You do need the crossover traps working.
    You do need a way to prevent steam from entering the dry return.

    Having working steam traps on the radiators is a safety to ensure that steam doesn't get into the returns.

    I would recommend repairing or replacing the radiators supply valve Because a good working valve can be used to control the flow of steam entering the radiator. And at the same time, you're fixing any leaks making your system tighter.

    Orifice plates make more sense in a apartment complex where the building doesn't want tenants messing with the heat distribution.

    So... You have a boiler selected that you know is large enough to fill the system.
    You know that you need to keep steam from getting into the dry return.
    All you need now to fill the system with vapor steam, is good air venting.

    " If air can't get out, steam can't get in"

    So if you can vent the air faster then the boiler can push the air out, you will fill the entire system with less than 4 oz of pressure.
    The only way a steam boiler can build pressure is if it can fill it faster than its venting. That includes Restricting it to much on the supply side.

    You know you need more venting.

    Looking over that video of the 3rd main, It is pipe very strange.
    The only way I see that working is if this intended to be gravity loop. Or it was a way to add water volume to the boiler.
    I dont understand why theres 3 pipes.
    Are there any other main lines that are dripped into The Wet return?
  • johnnygreenhamjohnnygreenham Member Posts: 41
    @AMservices: thank you for that long detailed post, appreciate the response.

    Q:"Are there any other main lines that are dripped into The Wet return?"

    A: No. No other pipes exist in the building. Just what's in the videos. The fin tube radiator return was the only pipe that returned into the wet return from the side.

    @AMservices "You don't need differential loops or any contraptions associated with the dead men's vapor systems."

    A: Well that's good to know. Just haven't got my head around why it would be ok to leave it out of the system and not have to replace it with something else. I read this from Dans book and this is why I thought I would need to add more contraptions unless the following in not regarding a vapor system or these are things I would be installing on a new boiler regardless?

    Page 392 (revised version) "If you see a differential loop on a boiler-replacement job, best thing you can do is leave it alone. If you remove it, you'll probably have to install a boiler-feed or condensate pump, as well as float & thermostatic traps at the ends of the mains. You may even have to re-pipe most of the returns so they run downhill to the condensate receiver".

    I will read more and see if I fully understand why I can leave it out. Really appreciate people patients, this steam thing is addictive and also frustrating.

  • AMservicesAMservices Member Posts: 490
    Dont take that quote about the differential loop as a blanket statement. No two steam systems are exactly the same.

    To understand what devices like differential loops and boiler return traps do, you have to understand how condensate returns to the boiler.

    In the boiler, when water starts exploding into steam, this is the highest point of pressure.
    Where all the problems begin.
    As pressure starts to build above the water line, the water will be pushed down and out through the return.

    For every pound of pressure, you will raise water 28" in A vertical column.

    That vertical column is the last drop the retuning condensate makes before falling into a wet return.

    So how does water get the pressure needed to return to the boiler?

    2 ways.
    First, gravity and the weigh of the water.
    Second, (this is the magic trick the differential loop uses) Equal Pressure.

    To simplify a differential loops purpose, what it does is equalize the pressure between the supply and return. With equal pressure on both sides of the water, it drains easily back to the boiler.

    you dont need a differential loop is because your new boiler will be piped with a equalizer line.
    This is the pipe a the end of the supply header that connects to the return, where the Hartford loop ties in the main return.

    What you need to make sure of is that you have at least 30" between the top of the boilers water line and the bottom of the dry return main.
    Keep the pressure low with good venting, good balance and a good vapor stat.

    If the pressure gets to high, water will back all the way up into the return main.
  • johnnygreenhamjohnnygreenham Member Posts: 41
    "you don't need a differential loop is because your new boiler will be piped with a equalizer line."

    That was the bit of information I was looking for and could not understand why removing a piece of safety would be ok without having some sort of replacement. I've read a fare bit about the Hartford Loop but no where did I read that the equalizer pipe leading from the header to the loop could do the differential loops job so to speak. Much appreciated. Ordering boiler today. It's exciting and frustrating all at the same time when learning but not always grasping concepts straight away. Thanks again for the education.
  • AMservicesAMservices Member Posts: 490
    Page 105 LAOSH,
    Equalizer sizing
  • johnnygreenhamjohnnygreenham Member Posts: 41
    @AMservices Got it, nothing like a bit of light reading over breakfast! Thanks
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