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    Understanding converting from steam to hot water (38 Posts)

  • dpeart dpeart @ 10:22 PM
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    Understanding converting from steam to hot water

    Currently my understanding is that the house is a two pipe steam system.  I would like to entertain the thought of changing the system to hot water to get access to a cheaper source of fuel.  In the article here at heatinghelp.com it says to make sure that you have enough EDR to switch from steam to hot water.  I've also read that steam is typically over sized, but you should run the numbers.

    I ran my heat loss numbers using the Slant/Fin app.  I ran them two ways.  1. as the house is today (not a stitch of insulation) and 2. what it would be after insulation is added in the attic and the crawlspace.  I also plan to do air infiltration remediation, but that didn't figure into the numbers at all.

    The heat loss numbers are 128MBH and 95MBH respectively.  This was much easier to use than the spreadsheet floating about.  I liked the options of picking 8" brick, fur, 1/2" plaster.  Instead of just 8" brick.  Seemed more accurate, but is this app OK to use?

    I added up the radiator EDR (as best I can), I only have the height and pictures of them. They are 4 column 26" tall and appear to be connected across the top.  I was able to count the number of sections from the pictures.  My total EDR is 300.5 on the first floor, and 247.27 on the second floor.

    If I take the total EDR and multiply by 1.33 ( can't even remember where I read to multiply by that factor, but it is supposed to account for the volume of the pipes I think) I get ~728.5.  This matches the size of the boiler in the basement a Smith bb14-*-5 for capacity.  That made me think I may have done something right, or maybe I just over sized as well.

    Now to figure out how much heat the radiators can radiate you multiply the EDR by 240 for steam or 180 for hat water.  Is this EDR the one before multiplying by 1.33 or after?  I was thinking before so I got 131MBH and 98.5MBH respectively.  Yes the pipes are in heated space and will provide heat, but it didn't seem right to count them.

    So it looks like for steam in the uninsulated house the system was pretty closely matched between capacity and heat loss and after I do some insulation work I should be pretty closely match with a hot water system as well.

    Does any of this make sense?  If the other factors of converting steam to hot water hold out does it sound like I could make this work?

    thanks,
    dave
  • Steamhead Steamhead @ 11:00 PM
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    Don't even think about it

    even if the radiators could handle the load on hot-water, you'd have to run at least ten times the pressure of a steam system to fill the system with water. This higher pressure WILL find any weak points in the piping and radiators. You'll see them as leaks.

    I've seen buildings where this has happened. It's not pretty.

    Steam systems often have pipes that run in outside walls, which may or may not be insulated. If you fill these with water, they may freeze and burst.

    Also, you may find the return lines will not handle the needed water flow. This means you'll have to repipe them.

    Whatever trouble you're having with your steam system, it's fixable. You don't need to convert it to have an efficient, comfortable system.
    "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.
  • Eastman Eastman @ 11:44 PM
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    Don't worry, his place already flooded.

    10 times steam pressure is not much though.  Can steam rads rust out so badly that they become unusable for hot water?  What are the warning signs to look for?  Could the system be checked somehow with an air compressor?
  • dpeart dpeart @ 12:10 AM
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    got to replace everything

    because of the flooding so I"m looking at all my options.

    I don't see myself going with steam, not because it is steam, but because of the cost of fuel oil.  I'm fine with hot water because I can supplement with wood, but if that doesn't work I'll probably end up going with a heat pump and forced air.  The wife gets AC if we go that route as well.

    Just trying to understand what options there are.  Part of that is making sure that I understand the process as well.

    thanks,
    dave
  • Eastman Eastman @ 12:31 AM
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    converting to forced air

    is like the nuclear option.  The potential for a few leaks to repair after a hot water conversion certainly doesn't warrant gutting the system.  Even if you have to replace the supply/return piping, I should think such a conversion would be a snap compared to installing forced air.
  • Steamhead Steamhead @ 12:37 AM
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    You don't tell us

    what condition your system was in before the flood, what boiler it had etc.

    A Burnham MegaSteam is far and away the best residential steamer, this would be a good choice if you don't have natural gas available. Unfortunately Burnham throws a temper tantrum every time we tell them we want a MegaSteam with a gas burner, but there are several other boilers that work well with gas burners such as the Smith 8 series, Slant/Fin Intrepid or Utica Starfire/Columbia CSFE series.

    If you install a heat pump and get flooded again, you'll have to replace all the ductwork, whereas steam piping and radiators should still be usable. Plus you will never get the same comfort as you do (or should) from steam. Dan wrote an article some years ago about a heat pump in a police station that the officers wanted to use for target practice- wonder why?
    "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.
    This post was edited by an admin on October 20, 2013 1:27 AM.
  • Eastman Eastman @ 12:46 AM
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    Are there any

    small two stage steam boilers?
  • Steamhead Steamhead @ 1:26 AM
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    Not yet

    currently there are a couple of Midco radial-flame burners being tested in residential boilers. These can modulate as well as do lo-hi-lo. On one of these, the stack temperature was running rather high- I don't know if or how that was resolved.

    But at least they're working on it.
    "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.
  • Eastman Eastman @ 1:36 AM
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    Nuts

    The problem with steam is that you can't get back to the original characteristics of a coal fired system.
  • ttekushan ttekushan @ 3:08 AM
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    The only place is on very large systems

    and if you have the right controls and burners.

    It is something to behold.

    Even heat distribution, quiet operation and very economical fuel usage.

    Can't wait for the small ones that Steamhead mentioned.
    terry
  • Eastman Eastman @ 3:29 AM
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    If it hasn't happended by now...

    it's not coming.  I think Steamhead is thinking of Mark S's project, but that's not really what I would consider a small system.
    This post was edited by an admin on October 20, 2013 6:11 PM.
  • dpeart dpeart @ 8:48 AM
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    Not trying to be elusive

    OK here is the back story, maybe it will help explain where I'm coming from.

    I live in TX and plan to move to VA to get closer to family in ~3 years.  I was looking for property there to buy. This house came up for sale and I couldn't pass it by.  It was built in 1927, solid brick, the brick looks amazingly good with only a couple small cracks in the mortar that can be fixed with some re-pointing.  The crawl space and basement are stone.  The original owners who built the house lived there until they passed away ~4 years ago.  The house was sold, and eventually ended up in foreclosure where I bought it.  Even if the house in an entire loss and I have to build an entirely new house, I'll still be OK with the purchase, but think that won't be the case, and hope to get it working with repairs and some smart upgrades.

    The flooding happened because the house was vacant and the pipe in the basement burst.  I'm assuming it was from freezing, but don't know for sure.  The bank had the house winterized later when they took over.  I have to have all the plumbing pressure tested to make sure there is nothing else wrong.  There are no signs of any water damage throughout the house, besides the basement, so I'm hoping that the burst waterline in the basement effectively drained the plumbing system, but I'll know later when the plumber does his thing.

    I've not seen the house, just have a couple hundred pictures my brother took so I could see it.  He also took down all the dimensions of the house and I've drawn it up in my housing program to figure sizes, etc.  This is what I used to calculate everything so far.  I'll be flying up there over thanksgiving to see for myself.

    In the meantime I want to figure out some kind of a plan too get the house fixed up and liveable as I will rent it out until we move back home.

    So that is the why I'm here in the first place.  With the heat calculations from Slant/Fin and now Buildit Solar it looks like I'll be right around $8000 per year for heating oil.  That is a lot of clams and my main motivator to get something that will be supplemented with wood.  Wood is free as trees fall on the farm, they have to be removed from the fields so I have to cut them up and burn them anyway.  I may as well heat the house with them.  I can easily support 10-13 cords a year with wood gathered this way.  My brother heats his house exclusively this way with a Portage and Maine outdoor wood boiler.

    I don't see the house flooding again as it won't be vacant, I'm not willing to spend $8k per year for heating oil.  I'd prefer having radiant heat over forced air, but if that won't work forced air is my last choice.

    Maybe that helps explain why I'm trying to do what I'm asking.

    thanks for all the help.  Good information like this is essential for me to make a good decision.
    dave
  • Steamhead Steamhead @ 2:59 PM
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    The basement is usually the last to freeze

    you will need to pressure-test everything on both the plumbing and heating systems. Don't be surprised if there's a lot more damage.

    There are, or were, wood-fired steam boilers, but since no one around here wants to deal with all the work involved in solid-fuel heating, I haven't kept up with them.
    "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.
  • Eastman Eastman @ 4:09 PM
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    8 thousand

    How did you get 8 thousand?
  • dpeart dpeart @ 4:30 PM
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    8k

    I ran the numbers in Slant/Fin and BuildItSolar and you can put in the cost of heating oil per gallon along with the efficiency of the boiler and it will calculate the annual cost based off the heat loss, degree days in the area, and efficiency.

    Both came up with a similar number of $8k per year at $3.66 per gallon, 85% efficiency and 6700 heating days per year.  I got 6700 from averaging the last three years in the area.

    I plan to try and figure out the oil company that has been delivering oil to that residence and see if they will tell me the average number of gallons purchased per year or something.

    dave
  • Eastman Eastman @ 4:57 PM
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    6700?

    That seems too high, I got 3100 with a base tempreture of 55.
  • dpeart dpeart @ 5:24 PM
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    Base Temp

    I'm assuming that the base temp is the temp you keep your house at, right?

    I ran the numbers at 70F and got 6009 ( I wrote the wrong number before).  I just re-ran with 65F and it drops to 4696.  That is quite the drop for 5F, I think I could live with 65F. Do you really keep your house at 55F?  That is way too cold :)

    dave
  • Eastman Eastman @ 5:28 PM
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    Base temp

    is the outside temp.  It's the temperature at which you would allow your heating system to turn on.  55 might be a bit low, but I think it would depend quite a bit on the level of solar gain the house receives.
  • Jamie Hall Jamie Hall @ 6:35 PM
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    Something isn't quite kosher here...

    The place I care for is in southern New England.  0 Fahrenheit design temperature, and it does get there, believe me.  No insulation to speak of.

    The heating system is a Hoffman Equipped vapour system, with a Weil-McClain boiler (very carefully installed and maintained by a really good Wallie, by the way).  Total EDR of the system is about 1500.

    I do burn close to $8,000 worth of fuel oil every year.  However, it would appear that my EDR is about 5 times yours, which suggests to me that somewhere in your arithmetic there is a major error.  Now if I multiply your EDR by 240, to get the BTU, I get 131,000 -- not 131 m[illion]btu.  Perhaps that is the problem?

    Recheck your numbers.

    And, having done that, I assume that you don't have access to natural gas.  If you do, the thing to do is to use a natural gas fired steam boiler, and bring the existing system up to snuff.  If you don't, you should at least investigate the possibility of using an LPG fired steam boiler; at the moment, LPG is somewhat less expensive than fuel oil.

    If you do decide to go with hot water (or air) and wood, I hope that you are young and spry; I've lived with wood heat (in Vermont) and it is a good deal more work than one expects it to be.  Further, should you ever want to sell the place, wood as the primary heat will, in many cases, be a deal killer,  Always assuming that your building inspector allows it in the first place!
    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
  • Eastman Eastman @ 7:05 PM
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    Isn't it about 1/3 of your EDR?

    First floor was 300 something, second floor was 250 ish.
  • Jamie Hall Jamie Hall @ 7:35 PM
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    You're right

    I misread.  Still -- a factor of three rather than a factor of 5.
    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
  • Eastman Eastman @ 8:19 PM
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    how many gallons

    When you say 8k worth of fuel, how many gallons does that come out to be?  Are you paying about the same in New England as West Virginia?
  • dpeart dpeart @ 8:29 PM
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    Gallons

    I priced it at $3.66 because that was the average cost I found. This week I'm going to try and get a hold of the local oil delivery place and maybe I can get some real historical numbers.

    I don't want to go with only wood, just wood in addition to heating oil.  I would plan on using wood but have a convenient backup.

    The design loss of the house is about 127,846 BTU/Hr per Slant/Fin.

    dave
  • Eastman Eastman @ 8:33 PM
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    Yeah

    I'm just wondering what Jamie is paying per gallon.  The 8k estimate you're coming up with has got to be ridiculously too high.  It's probably somewhere in the 2 grand vicinity.

    And wouldn't that affect your decision process?
    This post was edited by an admin on October 20, 2013 8:35 PM.
  • dpeart dpeart @ 9:01 PM
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    Cost

    Yes, if the cost is reasonable I would prefer sticking with what is there.  I would just replace the existing boiler with a new one, sized properly. 

    My main motivator is cost.

    dave
  • Jamie Hall Jamie Hall @ 9:27 PM
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    See immediately below --

    I'm paying $3.659 per gallon (bulk buying contract).  I'd agree with Eastman here -- I'd bet your proper number should be around $2500 per year for the oil.  Recheck everything!

    I quite agree that cost is a powerful motivator!
    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
  • Jamie Hall Jamie Hall @ 9:27 PM
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    See immediately below --

    I'm paying $3.659 per gallon (bulk buying contract).  I'd agree with Eastman here -- I'd bet your proper number should be around $2500 per year for the oil.  Recheck everything!

    I quite agree that cost is a powerful motivator!
    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
  • Jamie Hall Jamie Hall @ 8:36 PM
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    That design heat loss

    is almost exactly one third of the place I care for.  The price you are quoting for oil is almost exactly what I pay.

    I still say something is wrong with the calculations on cost (the calculations on EDR look about right).
    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
  • Ironman Ironman @ 9:28 PM
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    VA?

    Where in VA is the house located?

    I'm located near Staunton and we're typically looking at about 4500 degree days here.

    We service anything within about an hour, if you're looking for a contractor that does steam. We also do wood boilers.
    Bob Boan



    You can choose to do what you want, but you cannot choose the consequences.
  • dpeart dpeart @ 10:00 PM
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    Goshen

    Please please please contact me. I've called so many people in Staunton trying to find someone to go look at the place for me.

    thanks,
    dave
  • Ironman Ironman @ 10:46 PM
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    Goshen

    In my area.

    I sent you a p/m.
    Bob Boan



    You can choose to do what you want, but you cannot choose the consequences.
  • dpeart dpeart @ 10:55 PM
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    Where are the PMs?

    I can't find my way around this site well enough to find where the PMs are.  Where can I find them?

    thanks,
    dave
  • Ironman Ironman @ 11:00 PM
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    P/M

    Personal message.

    It will show up in your email address that you registered with.
    Bob Boan



    You can choose to do what you want, but you cannot choose the consequences.
    This post was edited by an admin on October 20, 2013 11:02 PM.
  • dpeart dpeart @ 10:03 PM
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    Degree days

    I actually ran my degree days from Staunton.  If I run at 65F I get about 4500 as well.  My misunderstanding was putting in 70F as I thought the number wanted was the temperature inside.

    dave
  • Ironman Ironman @ 10:49 PM
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    Degree days

    You could probably use 60* for Goshen.
    Bob Boan



    You can choose to do what you want, but you cannot choose the consequences.
  • Eastman Eastman @ 2:18 AM
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    peanuts

    Ironman and dpeart, don't cut the peanut gallery out. (please)
    This post was edited by an admin on October 22, 2013 2:57 AM.
  • Ironman Ironman @ 8:47 AM
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    Peanut gallery

    I've made arrangements with dpeart to evaluate the system and then make recommendations on how to proceed.

    The house is vacant and winterized and he is in the process of closing on it. It may well be after January before any work is done.

    I'll keep the gallery posted.
    Bob Boan



    You can choose to do what you want, but you cannot choose the consequences.
  • dpeart dpeart @ 12:25 PM
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    Will keep it updated

    I'm in the process of getting a complete energy audit done.  Then insulation and air infiltration work, then an updated heat loss calculation.  This will then let us proceed with heating work.

    It will be a long process, but it should be a fun ride :)

    Bob, it was good to talk to you yesterday, you should get your info in the "Find a Contractor" page, I would have been able to contact you a lot earlier :)

    dave
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