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Steam advice

wesPA Member Posts: 19
Good evening all,

My first post here. I have been following this site for years and have learned so much from everyone, thanks!

I work in the trade doing mostly commercial HVAC service and some install. I encounter some steam from time to time, but very little. I was asked to look at a system by a friend of our family. The house has an oil fired EFM steam boiler ( 1 pipe radiators) that unfortunately has cracked prior to the current owners moving in due to improper winterizing. I will post the pics I have. I have all the radiator info and am in the process of figuring out the existing EDR. I was curious if the existing boiler matches the radiation. Some things i noticed: Asbestos, open brick chimney, only 1 main vent. I would like any feedback you folks would have on the current near boiler piping, etc. They are looking for advice on whether to keep the system or not, and if so what all needs to be addressed for a system replacement. The current boiler has a tankless coil for DHW The house is about an hour from me in north central PA. I can give more details if needed. Thanks for any input! If my photos didnt load, i will try again


  • Fred
    Fred Member Posts: 8,518
    Need some pictures! What cracked? Pipes and/or radiators? If so, it must be a hot water system as a Steam system wouldn't have water in the pipes or rads except a little condensate which wouldn't be enough to crack the pipes or Rads. If it is steam and the wet returns or boiler block cracked, that is possible but pictures are a "Must" for the kind of advise you are asking.
  • Lance
    Lance Member Posts: 170
    One pipe steam is great. But it is old. So many things will need to be checked. A new boiler is great but only when properly connected and protected. Pitch of pipe is important, venting system air and flue draft is important. Returns may need flushing or replacing. Characteristic of steam is you will not be higher than 82% Afue. Properly done it will be quiet and comfortable. But it all depends on if it was done right from beginning to end.
    You will need to know it all!
  • Jamie Hall
    Jamie Hall Member Posts: 17,060
    Well, as @Lance said, it's old technology. However, old isn't bad; a one pipe steam system will run essentially forever as long as a small amount of intelligent attention is paid to it.

    You will need a new boiler, if it is the old one that cracked (which, if it was allowed to freeze with water in it, wouldn't surprise me a bit). There are many good steam boilers available; it is mostly a matter of adding up the EDR of the radiators and matching that reasonably closely. If the chimney truly isn't lined, you may need to have it lined. This isn't hard; a good chimney firm can do that.

    If there are wet returns -- which there may or may not be; one pipe steam systems don't always have them -- they may have been damaged by freezing as well, and may need to be flushed out in any event. They usually aren't a big problem to replace, if that is needed.

    Asbestos can be removed. It can also be encapsulated. The choice there depends on just how paranoid the owners are -- and on the impact on future sales value of the house. If you do have it removed, you have to reinsulate the pipes. Removal is a big deal. Reinsulation isn't.

    I don't see the pictures, but the odds are that the new boiler will also need new boiler piping. Since you've been following this site, you will have some ideas as to what beyond the manufacturer's minimum standards might be advisable. Again, though, if you can handle threaded pipe, not a big deal. Just do it right...

    Venting? Main vents! We can help with that when you get there.

    As to efficiency. True, a steam boiler, by the nature of physics, won't get much over 82%. Around 86% is the theoretical maximum for oil. Don't worry about it. The only way to go over that is with a condensing hot water boiler, set up to condense. Great if you are installing a whole new system -- but you'll never recover the expense of a whole new system that way, and it's unlikely that you would be able to convert one pipe steam to hot water without major expense anyway (and it won't condense much of the time). Keep the one pipe steam and don't worry about the efficiency.

    There are better ways to provide hot water...
    Br. Jamie, osb
    Building superintendent/caretaker, 7200 sq. ft. historic house museum with dependencies in New England
  • leonz
    leonz Member Posts: 421
    The Electric Furnace Man (EFM) Boilers are a very high quality product and they have been making boilers and furnaces since 1948 or so.
    One pipe steam is a very very simple method of heating and it sounds like the basement was left wide open during a winter.

    We need more pictures to see what you have.