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    surge tank needed? (12 Posts)

  • Brant Brant @ 9:44 AM
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    surge tank needed?

    I am doing an oil to gas replacement of my home steam heating boiler (rated at 210,000 BTUs).  I am staying with steam since the cost of moving to a hot water system will be significant.  The contractor who I am planning upon using for the work - and whom I find to be reputable - is recommending an option for a surge tank to be installed.

    I understand the need for an expansion tank with a hot water system due to water not being a compressible fluid.  However, I have never heard of a surge tank as he is referring to it for steam.  The exact quote from the pricing proposal option is "Surge tank to prevent pipe noise". 

    Can someone tell me what this would eliminate pipe noise?  I'm not getting a decent explanation from the contractor.

    Thank you!!
  • nicholas bonham-carter nicholas bonham-carter @ 10:22 AM
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    surge tank=snake oil?

    if the new boiler has been sized correctly for the radiation edr; and if the piping instructions from the manufacturer have been followed as a minimum; and if the pressure is not over a pound or so; and if the main [not radiator] venting is adequate, then your system should be quiet, economical, and comfortable.
    a surge tank could be useful for some old, and badly installed boiler to help it limp along for a few months while you are trying to sell the building, much like putting sawdust into the noisy transmission of an old car you are trying to sell.--nbc

    more thoughts:
    the pipes must be insulated, which you can do yourself following instructions on this site, and the supplies, and return pipes should have no dips or sags which could trap condensate, and cause water-hammer. a visit to the boiler mafg's site will show you the installation instructions, piping sizes and layout, etc. which could be a part of the contract with your installer. you could also ask the mfg. if they would advise on the surge tank installation.
    This post was edited by an admin on October 20, 2011 10:46 AM.
  • Rod Rod @ 10:51 AM
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    Surge Tank?

    Hi- Going from oil to gas - Are you changing boilers (new boiler) or just changing burners?  If the same boiler -Were there problems in the past and what were the problems?
    The "surge tank" idea  would raise the question for me as to whether this guy really knows much about steam heating. Ask him exactly what a "surge tank" is and how and where it's installed and what is it supposed to do for you and why you need it.
    - Rod 
  • Jamie Hall Jamie Hall @ 2:13 PM
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    Ah... no

    He may be reputable, but he doesn't know steam.  Nor, for that matter, hydronic -- where the term is "expansion tank".
    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
  • Brant Brant @ 4:24 PM
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    good comments all. But...?

    Thanks for the good comments...  But can someone explain what a surge tank would do mechanically on a steam system condensate return?  I'm just don't get this as a concept and how it might help an old system limp along.  I'm at a point of curiosity only   (I get steam concepts since I used to work as an engineer in a powerplant).  I've also lost faith in my contractor.  :( 
  • Brant Brant @ 4:24 PM
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    good comments all. But...?

    Thanks for the good comments...  But can someone explain what a surge tank would do mechanically on a steam system condensate return?  I'm just don't get this as a concept and how it might help an old system limp along.  I'm at a point of curiosity only   (I get steam concepts since I used to work as an engineer in a powerplant).  I've also lost faith in my contractor.  :( 
  • Rod Rod @ 6:35 PM
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    Surge Tank?

    Hi- You need to ask your contractor the question "What a "surge tank" would do mechanically on a steam system condensate return" as we're not familiar with the term as applied to steam systems.
     if the condensate is very slow to return to the boiler and this causes the boiler to run out of water with the consequence of the LWCO being activated, there are some cases where a reservoir is added to increase the volume of water available to the boiler. However these cases are fairly rare and have nothing to do with "surge". Usually a slow return of the condensate means the wet return is plugged up and needs cleaning or replacing. This should be checked out first before any thought of adding a reservoir.
    - Rod
  • Mark N Mark N @ 6:57 PM
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    Anti-Surge Tank

    On page 45 of "The Lost Art of Steam Heat" a device called an anti-surge tank is mentioned. It is used in the supply piping as a steam separator. It will slow the velocity of the steam and leave the water in the boiler. Proper near boiler piping will also do the same thing. I remember a thread from about a year ago and the manufacturer of that boiler sold a steam separator with their boilers.
  • Mark N Mark N @ 7:05 PM
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    Steam Separator

    Did a quick search and came up with Union Steam. Their web site is unionsteam.com. They sell separators for their boilers. So it would seem that there is at least one manufacturer that recommends them for their boilers.
  • nicholas bonham-carter nicholas bonham-carter @ 11:12 PM
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    Surge tank=condensate tank?

    You don't need that condensate tank either. Your boiler whether 100,000 btu, or 1,000,000 btu has been sized not only for steam heat production but also for water capacity , no condensate feed tank is necessary, nor is it desirable as it adds a new level of complexity, and only benefits the installer.
    Unlike forced air, or hot water heating, a gravity fed steam boiler needs no extra electricity beyond the fire control system for the burner, whereas a condensate pump needs constant power for its useless operation.--nbc
    This post was edited by an admin on October 20, 2011 11:20 PM.
  • Mark Eatherton Mark Eatherton @ 7:31 AM
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    Guys...

    Could it be that the old beast had a huge steam chest and condensate holding capacity, and the newer boiler has less condensate capacity, and the contractor is putting it on the return to simulate the large water holding capacity of the old system, thereby avoiding over filling the system?

    Not sure in my minds eye how that would avoid piping noise issues, other than possibly water carry over from too high a standing water level and the associated hammer.

    I do agree with the other posters that the questions should be asked of the contractor. It is his decision to include it. If he has a reasonable explanation, other than it making the system operate quieter, then I'd consider it a valid situation.

    The term I've seen and heard used is a range tank, not a surge tank. Maybe it is a surge tank being used in a range (return) tank application...

    Just thinking out loud here...

    ME
    It's not so much a case of "You got what you paid for", as it is a matter of "You DIDN'T get what you DIDN'T pay for, and you're NOT going to get what you thought you were in the way of comfort". Borrowed from Heatboy.
  • nicholas bonham-carter nicholas bonham-carter @ 10:07 AM
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    range/reservoir tank

    i have one on my return, so naturally i approve. steamhead has a wonderful picture of a big one, which maybe he can dig up again. burnham or w-m show one on one of their installation manuals.
    however a steam separator is not a good substitute for proper pipng.--nbc
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