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From no Water Hammer to Floor Shaking

I do not know who to turn to for an issue i am having and maybe someone here can help me. I had a very old boiler replaced that had worked very well for about 80 years. it was an oil boiler that was converted to gas and is a one-pipe steam boiler setup and on top of that it was insulated with asbestos. No one ever wanted to work on the thing, so i would just do minor maintenance myself by just draining it once and a while, it was replaced last year with a crown boiler and now i am experiencing an abundance of water hammer and the person that installed has almost no clue to what he is doing. the part that angers me is that this is my grandmother that is going to end up being taken advantage of. first she is being told that there is sludge or dirt in the pipes, and i can understand this and i constantly change out the water in the new furnace, and it isn't crystal clear but it's not sludge... I'm 30 years old, and never in my life have i heard this much water hammer come from our One-pipe setup. It was literally day and night with this new furnace. Went from no water hammer and good heat, to unbearable and possibly dangerous and consistent hammering

The following now happens but never did
Downstairs closer to the boiler, you hear the "marble effect" type water hammer, where you hear water cruise from end of the pipes to another
The water hammering does not discriminate, It happens everywhere in the entire system. Every pipe is pitched toward the boiler to some degree, (there may be 1 pipe that is level). all the radiators are pitched toward the inlet valves.
The inlet valves are all leaking from the valve knobs, they hammer at the inlet valves themselves as well.
and this is not a noise that is tolerable, it's not like a tink tink tink... it is more of a BANG BANG BANG until that radiator is completely hot.. and the pressure release on the radiator is not consistent at all. you can clearly hear that the pressure varies, and this is when the hammering is happening.

personally i feel the issue is due to the pressure in the system not being consistent. There seems to be much to much pressure going to the system in general, the inlet valves do not seem to be able to handle it, they all leak water while the system is active.

the person who put in the system is now saying that the pipes may need to be replaced, because of buildup of whatever is inside them. which for 80 years didn't do anything but all of a sudden is having it's effect.

I am looking to get in touch with someone who may have experience with this type of setup and issue. Thank you very much


  • FredFred Posts: 7,814Member
    Where are you located? There are excellent Steam Pros on this site and maybe we can suggest one, based on your location.
    - Water hammer is typically the result of steam hitting water sitting in a pipe. You say the pipes all pitch back towards the boiler. They should pitch towards the return pipe, which may or may not be towards the boiler.
    - The new boiler needs to be installed so that the water line in the new boiler matches that of the old boiler. If not, there is a good chance the dry returns could become wet or the wet returns can become dry. Both will cause hammer.
    - If you can post some pictures of the piping above and around the new boiler, that will help us see what is going on.
  • JUGHNEJUGHNE Posts: 5,579Member
    Especially pictures of the pressure gauge, (while in operation if possible and note the highest reading it shows). Also picture of the pressure control box with the scale of numbers on the front of it......this may be a grey box or one with a clear front......either are approx. 4 X 4 square.
  • KC_JonesKC_Jones Posts: 4,093Member
    Did the installer skim the boiler after install? Some of your description sounds like surging which can happen after a new install when it isn't properly skimmed.
    2014 Weil Mclain EG-40
    EcoSteam ES-20 Advanced Boiler Control
    Boiler pictures updated 2/21/15
  • Jamie HallJamie Hall Posts: 10,279Member
    You've kind of answered your own question: the person who put in the new boiler messed up. Just how he (or she) messed up, though, is the question, and the pictures of the piping around the new boiler -- anything that was redone -- will help a lot.

    In the meantime, do check the pressure as has been suggested. It is probably much too high.

    I almost hate to ask this one, but how was the size of the new boiler determined? It may be much too large, which will also cause a lot of trouble.

    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
  • Dust906Dust906 Posts: 3Member
    edited April 2017
    this is my dilemma.. my grandfather worked for the gas company... the boiler that we had was very LARGE... im 6'4 and it was about as tall as me and shaped kind of like a rounded hour glass.. im going to try and take pictures soon of the entire situation..

    Long story short, i was not around for a year, and the 80 year old boiler we had was a manual fill, and i had been maintaining it for the last 10 years, and the year past i was not around and the boiler ran out of water, and apparently almost blew up... (what the guy said) i was not here to maintain the boiler. The boiler was literally entered into a yearly contest for oldest boiler in CT...

    I live in the bridgeport area of connecticut..
    like i said i will try and take pictures and ill add everything i post to my original post

    I know that there should have been pictures taken, tests run on the pressure the system was putting out, and information taken on the size of the boiler and i think distance to the floor was a factor.. But... again i was not around, and now it will become a burden because this is a old setup

    Fact..... It worked perfectly for 80+ years... now it's not right

    might not even be the right boiler for all i know.. i do not know the math for steam boilers unfortunately for me.
  • Jamie HallJamie Hall Posts: 10,279Member
    Almost sounds as though we really need to go back to square one on this one.

    The sizing of steam boilers is really very easy. They are sized on the basis of the size and number of radiators to which they are connected. There are tables on this site (and other places) which can be used to look up the "EDR" of each radiator. Then you just add up all the EDR's and select a boiler which is rated for that value -- no bigger and no smaller, within 10 percent or so.

    Then you install the boiler and connect it to the old piping. Again, not rocket science -- if one reads the installation manual, which a lot of people don't bother doing, and if you match the water level in the new boiler to the water level in the old one -- which again a lot of people don't bother doing.

    There are several very good men who post on the Wall who will serve that area.

    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
  • Dust906Dust906 Posts: 3Member
    the problem with that is the old boiler needed replacement because no one was here to manually fill the old boiler.. and it burnt out.. so when they took out the old boiler, no one knew where the correct level was.. i also think staring at the new one isn't going to fix the problem much. the guy only wants to consult with other people, he doesn't really "try" anything and touching the damn boiler voids "his" warranty
  • MilanDMilanD Posts: 1,107Member
    Pictures please, boiler, controls, near boiler piping, pressure gauge, pressuretrol, mains, wet and dry returns... What is the op pressure set to? Water is hung up somewhere. Could be as easy as turning down pressure which may be waaay high, or more serious. A lot of smart people here and generous with their time and knowledge. Post pics.
  • KC_JonesKC_Jones Posts: 4,093Member
    @Charlie from wmass is a little over an hour from Bridgeport, CT. Charlie do you work in that area?
    2014 Weil Mclain EG-40
    EcoSteam ES-20 Advanced Boiler Control
    Boiler pictures updated 2/21/15
  • Charlie from wmassCharlie from wmass Posts: 4,053Member
    @Dust906 call me 413.841.6726
    Cost is what you spend , value is what you get.

    cell # 413-841-6726
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