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Bryant Steam Boiler BS 2 AAN 262 - correct pipes?

I just had this boiler installed before the winter to replace an old oil boiler.

2 issues..

Since we installed it i am woken up to radiator banging every morning. My system was quiet before we changed it.

2nd, i had another contractor in who said the boiler was installed incorrectly. They used 2 inch pipes instead of the recommended 2.5 inch. These both lead to a single 2 inch pipe which then leads to a 4 inch pipe that goes to the rest of the house. In a previous forum i read that this is wrong and voids the warranty as well as leading to an inefficient system.

pics attached

all thoughts welcome


  • dualpipesteam
    dualpipesteam Member Posts: 8

    JUGHNE Member Posts: 8,959
    Could you back up for the whole view of the boiler piping?

    Expect to hear the words: (butcherers......did anyone read the book??.....Sacrilege performed on a Dunham system......and I know it will come "You can't fix stupid". :/
  • KC_Jones
    KC_Jones Member Posts: 4,837
    The piping is to be 2 1/2" at minimum, the installation manual is very clear on this. Also specs minimum 15" from last boiler riser to first system take off, which I don't think you have.

    The warranty is pretty clear, it will not cover if the installation is not proper, no exceptions.

    I attached a picture from the manual and the warranty information.

    Was the boiler skimmed after installation? Without skimming it could be surging causing part of your issue, but primarily I would say your piping is the culprit. Those side outlet boiler are very sensitive to proper piping.

    You need to get the contractor back to fix their mistakes. Have you made final payment to them?

    2014 Weil Mclain EG-40
    EcoSteam ES-20 Advanced Boiler Control
    Boiler pictures updated 2/21/15
    New England SteamWorksdualpipesteam
  • dualpipesteam
    dualpipesteam Member Posts: 8
    i will post pics of the entire system later tonight.. appreciate the help
  • dualpipesteam
    dualpipesteam Member Posts: 8
    unfortunately fully paid but he is sending someone out and was mildly receptive to correcting it.. I got the usual we have been doing this since the 1960's. Also spoke to bryant and they claim the 2.5 inch is a guideline and individual installations may warrant individual approaches. guess they don't want to throw installers under the bus.
  • 1Matthias
    1Matthias Member Posts: 148
    Eek. Larry, Curly, and Moe have expanded their business. "Up to the basement!"

    In all seriousness, that needs to be redone to the manual's specs. What you have now is not correct.
  • Steamhead
    Steamhead Member Posts: 14,844
    That boiler is a re-branded Dunkirk. Dunkirk gas steamers are very sensitive to improper piping. Unless it is piped using the specs in the manual as a minimum, you will always have trouble with it.

    If we were doing that job, it would have two 2-1/2" risers feeding a 3-inch header, then a 3" takeoff to the steam main. This would make sure the steam was extremely dry before it went out to the system.
    All Steamed Up, Inc.
    Steam, Vapor & Hot-Water Heating Specialists
    Oil & Gas Burner Service
    New England SteamWorksdualpipesteam
    STEAM DOCTOR Member Posts: 1,368
    edited March 2018
    Three stooges. "A plumbing we will go". Check it out on youtube
  • dualpipesteam
    dualpipesteam Member Posts: 8
    edited March 2018
    More pics.
  • dualpipesteam
    dualpipesteam Member Posts: 8
    edited March 2018
    easier if i post this way

  • dualpipesteam
    dualpipesteam Member Posts: 8
    also heard the the steam return is above the waterline and this is an issue... not sure why. thanks for all the feedback..
  • New England SteamWorks
    New England SteamWorks Member Posts: 1,429
    Looks like you have a vapor system. I think you need one of us to take a look. Where are you located?
    New England SteamWorks
    Service, Installation, & Restoration of Steam Heating Systems
  • dualpipesteam
    dualpipesteam Member Posts: 8
    Located in Scarsdale NY.

    I believe I have a 2 pipe vapor system.