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Questionable near boiler piping install

I have one pipe steam system with a new boiler being installed. The old boiler, circa 1946 was only fired by me once, briefly, and the system did run quietly though it too about an hour to get any steam up from that behemoth. Beyond that i don't know how it behaved. At any rate, I got home from work to discover that the near piping had been done in copper, which set off immediate red flags though I hadn't thought about it when the contract was drawn up, unfortunately for me.

The existing piping seems to be a hybrid of parallel flow in the large main with counterflow branching off of that as well as two seperate counterflow lines with drips. Does the new piping make sense layout wise? The copper seems to be true and not pitched at all. Not pictured is the return loop which runs at the level of the main at the far end, drops should half way down for about 10 feet, then drops again the the level shown. There also don't appear to be any vents in the basement.

My question is, how bad are the problems with the work being done? I understand the copper joints won't hold up long term, but I'm not sure whether the contractor knows what they're doing at all at this point.


  • What to do about the new boiler

    You can go through the boiler installation manual with them, and make sure that they understand the instructions, which probably include advice against using copper.

    What was written in the contract between you and the installer? Was there any mention of following instructions from the manufacturer?

    Generally copper piping is a no-no above the waterline, and should be noted by the manufacturer.--NBC
  • Steamhead
    Steamhead Member Posts: 16,734

    they have one takeoff feeding two steam mains thru a bullheaded tee... another no-no. Each steam main should have its own connection to the header.

    And I can't tell, but are all those pipes 2-inch? If so, some of them are probably too small.

    They'll have to repipe this one.
    All Steamed Up, Inc.
    Towson, MD, USA
    Steam, Vapor & Hot-Water Heating Specialists
    Oil & Gas Burner Service
  • PurpleAmy
    PurpleAmy Member Posts: 3

    Thanks guys! The manual doesn't seem to mention materials other than for the relief. Those are 2" pipes. From a pure mechanical standpoint i don't think the copper will survive the motion in the floor twisting the header even. Knowing that this isn't right and that it's not going to work correctly on day one even, hopefully will make it easier to reach an amicable solution.
  • Rod
    Rod Posts: 2,067
    I&O Manual

    Hi- Do you have a copy of the installation manual? If not let us know the model -(It's on the manufacturer's plate on the boiler) and we can dig one out for you.

    - Rod
  • PurpleAmy
    PurpleAmy Member Posts: 3

    Is a weil mclain peg-40. The digital manual is on here http://www.weil-mclain.com/en/weil-mclain/pd-eg-gas-boiler/

    Also, is it correct to pipe this as a parallel flow system given the drips and partial parallel setup, or does the steam need to pipe downward into the system header as in a counterflow system?
  • Rod
    Rod Posts: 2,067
    Counterflow System with Driplines

    Hi Amy-  Okay, great you have an I&O manual. Look on page 14 at Table 7 and you'll see the recommends pipe sizes for the different piping. These are minimums and need to be strictly followed as undersized piping can give you problems.  In the instructions it doesn't state anything about using black threaded pipe and the installer may try to fall back on this and the drawings on Page 14, Figure 18 which might look like they might be copper as they show no threads. The come back to this is "Everybody knows you use black threaded pipe for steam lines" and  " Look on Page 16, Figure 20, they actually drew in the threads on the boiler piping!

      Ignore the drawing of a counterflow system Page 15, Figure 19. It's for a very simple single counterflow main. I've attached a drawing and some pictures of a counterflow system with a dropheader and drip lines which was done by Steve Gronski, a Rhode Island steam pro. Note in the drawing that the main vents are located at the far end of the main from the boiler.

     From the looks of it, your original system was nicely thought out.

    - Rod
  • Dave in QCA
    Dave in QCA Member Posts: 1,785
    Where to go from here?

    Unfortunately, WM does not specify no copper piping on steam as most of the other boiler manufacturers do.  They assume a competent installer knows that!

    If this system were mine, I would do the following:

    Have the contractor stop any further assembly of the copper piping.

    Replace all of the copper with black iron pipe and fittings.

    The manufacturer calls for a 2" riser and 2" header on this boiler, it looks like the elbow at the top of the riser reduces to 1 1/2".

    The to supplies to the system should each connect independently to the header.

    I can see the drips on your two counter flow lines and they seem fine.

    As for venting, there should be a vent at the end of each main and that needs to be addressed as well.

    obviously, none of these things were covered in your contract.  The contractor may have done other boilers like this and thinks its OK.  But, he doesn't know what he doesn't know.  Copper piping on steam will eventually leak at the joints, it just will NOT last.  Be prepared for a price adjustment to cover the additional thing that you will ask the contractor to do.
    Dave in Quad Cities, America
    Weil-McLain 680 with Riello 2-stage burner, December 2012. Firing rate=375MBH Low, 690MBH Hi.
    System = Early Dunham 2-pipe Vacuo-Vapor (inlet and outlet both at bottom of radiators) Traps are Dunham #2 rebuilt w. Barnes-Jones Cage Units, Dunham-Bush 1E, Mepco 1E, and Armstrong TS-2. All valves haveTunstall orifices sized at 8 oz.
    Current connected load EDR= 1,259 sq ft, Original system EDR = 2,100 sq ft Vaporstat, 13 oz cutout, 4 oz cutin - Temp. control Tekmar 279.
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