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Injection piping question

Mpj
Mpj Member Posts: 109
Went to a job today to help an electrician friend wire a injection system installed by somebody else. The supply injection leg was taken off the supply header (Weil Mclain CG series boiler) and the return leg was taken off the return header. The injection pump was on the return side of the loop pulling away from the radiant manifolds instead of "injecting" into the manifold tees.

I have never seen this done before, do you think that the system will work properly?

Thanks,

MPJ

Comments

  • Ironman
    Ironman Member Posts: 7,373
    Injection Pump

    There should be an injection bridge piped between the manifold loop and the primary loop with two closely spaced Tee's.



    I'm not sure I'm following your description. Can you post a pic or a diagram?



    See the attachment on injection piping.
    Bob Boan
    You can choose to do what you want, but you cannot choose the consequences.
  • Mpj
    Mpj Member Posts: 109
    Injection loop

    Having trouble uploading a picture. Something about a "tif" to a "pdf".
  • Brad White
    Brad White Member Posts: 2,398
    If

    your boiler supply and return are on opposite sides of your boiler (with intermediate piping or anything other than closely spaced tees or other hydraulic separators), you can count on that circuit forcing water into your secondary circuit.



    Ironman is on it. You need a bridge spanning the primary/secondary sides, running between pairs of tees on each circuit.



    Can you post a diagram or photos?
    "If you do not know the answer, say, "I do not know the answer", and you will be correct!"



    -Ernie White, my Dad
  • Terry O
    Terry O Member Posts: 67
    File conversion

    Tiff to pdf file conversions can be done through any one of many file handling programs. Irfanview for instance - http://www.irfanview.com/ - ....Or if you'd rather not want to download and install one of these, you can use an online conversion program.... see link: http://docupub.com/pdfconvert/

    Good luck!
    Terry O
  • Mpj
    Mpj Member Posts: 109
    injection loop

    Sorry for the crude drawing but art is not my specialty. The injection legs are coming off the supply and return headers same as the other zones. the injection circulator is pulling from the tees. I have never seen it piped this way before and I was just wondering if you guys would think it work or not.

    Thanks,

    Mpj
  • Mpj
    Mpj Member Posts: 109
    injection loop

    Terry O, thanks for the info. It took a little while but I got it.
  • Ironman
    Ironman Member Posts: 7,373
    Missing Circ?

    You're short one circ. - The injection circ!  It should be in the bridge between the main loop and the radiant loop.



    No, it won't work. What is there to cause flow in the bridge between the loops? The variable speed injection circ. must be in the bridge. And you'll still need a circ. in each loop - the primary and the radiant.
    Bob Boan
    You can choose to do what you want, but you cannot choose the consequences.
  • Mpj
    Mpj Member Posts: 109
    injection loop

    I made a mistake on the drawing. The only closely spaced tees are at the radiant loop. The injection legs are connected directly to the boiler headers.
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