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    Need Help with Sizing (10 Posts)

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    Need Help with Sizing

    I am doing an oil to gas conversion in my 2,300 square foot home in Westchester County, New York.  The home has steam heat.  I received 5 quotes for the conversion.  Two of the contractors did not measure the radiators when they visited my home.  The other three took measurements of all radiators in every room.  Of the three who measured, I received quotes for a Burnham IN6 (175,000 BTUs), a Burnham IN8 (245,000 BTUs), and a Bryant BS2 AAN 262 (262,000 BTUs).  Of the two that did not measure the radiators, one recommended a Weil-McLain EF-55 (200,000 BTUs) and the other recommended a Weil-McLain PEG-50 (175,000 BTUs).  I'm concerned about the wide disparity in sizing. I'm more interested in getting the right system than getting the cheapest system.  I have no experience in this area.  So, how do I, as a consumer, make sure the contractor is getting the size right?
  • vaporvac vaporvac @ 3:50 PM
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    Total edr?

    Could you get the total edr measurements from each of those that did them to compare? It could be that one of them is adding the pick-up factor into the boiler size which is redundant. You could also measure the rads yourself using the directions on this site. It might be easier, although I'm curious if they all measured them the same.
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    Total EDR

    I've asked each of the contractors to provide their total EDR calculation.  Keeping in mind I've never done this, when I measured and calculated last night, I came up with 396, which I believe translates to around 96,000 BTU.  Nor does my measurement account for bare piping in the basement (which will be insulated with this project) or for the fact that most of my heat comes from in wall cast iron convectors, for which I believe you add on a certain amount.
  • Chris Chris @ 8:14 PM
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    Size the Rads Yourself

    It's not hard. Page 66 of the document.. A steam boiler is not sized by btu/hr rather by sqft of radiation or Sqft EDR. Why convert when you could get a 86% efficient steam oil boiler. None of those being quoted to you in gas can touch that.
    "The bitter taste of a poor installation remains much longer than the sweet taste of the lowest price."
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    RE Size the Rads Yourself

    We've gone back and forth on staying with oil or switching to gas.  We're convinced that converting is the better choice for the long term.  Thanks for the document to assist with the EDR calculations.  Very helpful.
  • RobG RobG @ 12:11 PM
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    Where are you?

    Depending on your location, you might find a steam pro here. Sizing the boiler is the easy part. Finding a contractor to install it correctly is the hard part.
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    I'm in Larchmont (Southern Westchester).  I used the "Find a Contractor" search but nothing came up.
  • Rod Rod @ 1:27 PM
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    Replacing a Boiler

    Hi - It sounds like you are on the right track.  Attached is a form which may be of help to you. Calculate the EDR room by room.  The EDR for the piping is taken care of in the 1.33  “Pickup Factor” .   As for the “cast iron wall convectors”, post some pictures and the measurements and I’m sure some here can give you an approximate EDR measurement.
       If you’re thinking of going with natural gas, you might want to consider a wet based boiler with a gas power burner as these are thought to be more efficient than the standard gas boiler. Smith and Slant Fin have wet based boilers approved for gas power burners. Use the “Search the Wall Function” button as there is of lot of info on this type of setup.

    Switching to gas- The following will need to be taken into account:
    1. If you don’t already have one, you will probably need a stainless steel chimney liner.
    2. Is the gas service now connected to the house large enough to accomodate the new gas fired  boiler?
    3. The bid should include the permits and proper removal of the old oil tank.

    Be sure to take a look around this website as there's a lot of good info available. Here are a couple of links that will be of help to you:

    This is a good video on the importance of the proper configuration of the boiler’s piping
    If you don't already have them, there are some very good books on steam heating in Shop section of this website: The first one to read is called “We Got Steam Heat!”
    and the second one is "The Lost Art of Steam Heating”
    Both the books are easy reading and written so the home owner can understand them. A few evenings of reading will put you light years ahead in your knowledge of steam heating. 
    Take your time and learn as much as you can before making a decision. Doing your homework first really pays off!
    - Rod

  • RobG RobG @ 2:47 PM
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    Find a contractor

    Search using the zip code and expand the area. I looked at your zip and found a few. I would try Joe from Ecuacool, He is based in New Jersey but may work in your area. He posts on here regularly and does some fine work.
  • Charlie from wmass Charlie from wmass @ 12:59 PM
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    If there is enough traffic

    I am willing to get the Westchester County License. The fact they charge more than the whole state of Massachusetts and Connecticut combined makes people stay away for just a one off job.   New York Licensing is fragmented and all over the board.
    Cost is what you spend , value is what you get.

    cell # 413-841-6726
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