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Pumping Away Piping

HeatingHelp Administrator Posts: 637
edited February 2017 in THE MAIN WALL
Pumping Away Piping

Consider this piping arrangement using the Pumping Away method.

Read the full story here



  • phosgene
    phosgene Member Posts: 8
    How can I apply this air bleeding technique to a primary secondary piping set up ?
  • Solid_Fuel_Man
    Solid_Fuel_Man Member Posts: 2,646
    edited February 2017
    It's true! I've said it before and I'll say it again here: ever since I've been doing my installs "pumping away" commissioning is so simple. After power purging each zone: Turn on boiler, run zones, get heat, clean up, done.
    Serving Northern Maine HVAC & Controls. I burn wood, it smells good!
  • Zman
    Zman Member Posts: 7,569
    Absolutely true. Dan literally "wrote the book".
    I would point out that air eliminators also make pretty good dirt eliminators. I have noticed especially in older systems, that when the expansion tank is directly below the air eliminator, the tanks get debris in them. It is not a bad idea to put a Tee directly below the eliminator and pipe the expansion tank from the side of the tee. You can then install a valve to blow the debris on the bottom of the Tee. Probably not needed on every job, just something to think about.
    "If you can't explain it simply, you don't understand it well enough"
    Albert Einstein
  • Hilly
    Hilly Member Posts: 427
    Do you guys put a shutoff on each return line or leave them out like the diagram? I have done this setup since reading on still stick with the return line shut offs.
    Here's a pic of the most compact version I've installed.

    HVACNUT Member Posts: 5,841
    Is that 1 zone, split loops? If so then what you've got there is the only way you can do it.
    I still like to put a ball valve on my return manifold. I have stock in brass.
  • Hilly
    Hilly Member Posts: 427
    Just like the picture from pumping away with zone valves. You see the 4 return lines in the picture.
  • rick in Alaska
    rick in Alaska Member Posts: 1,457
    I have been using this method ever since seeing it in the book, and love it. It is the best way to make sure all air is out, without any air pockets left behind. I also do put valves on my returns just so I can isolate them if I need to.

  • Alan (California Radiant) Forbes
    Hilly: That's awesome.
    Yes, Mr. Dan has made my professional life a whole lot easier when I learned to install his purge assembly. Brilliant!
    8.33 lbs./gal. x 60 min./hr. x 20°ΔT = 10,000 BTU's/hour

    Two btu per sq ft for degree difference for a slab
  • HomerJSmith
    HomerJSmith Member Posts: 2,440
    Pumping away from an Xtank is good. Pumping away from an air eliminator, I don't know. There is a possibility of pulling air into the system. I like pumping into an air separator on the supply side (hottest water).
  • hot_rod
    hot_rod Member Posts: 22,157
    the confusion I hear over and over has to do with the need to pump into the new high efficient, high pressure drop boilers, and where to locate the expansion tank connection.

    The air sep performs best at the boiler supply, the hottest point in the system.

    But the expansion tank does not need to be on, or be able to be on the air sep, it needs to be near the inlet of the circulator(s)

    So if the circulator is at, or in the boiler, pumping the return side, choosing the correct expansion tank connection becomes a bit more confusing.

    With a multiple circulator P/S piping... now where?
    Bob "hot rod" Rohr
    trainer for Caleffi NA
    Living the hydronic dream