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Sizing of Hydraulic Separator

stoke
stoke Member Posts: 10
Short , fat , right ? The bigger the better ? If I understand this correctly, a min. size would be 1 1/2".

Comments

  • hot_rod
    hot_rod Member Posts: 22,022
    A two boiler piping? The separator is sizes to the largest load on either side. If the "A" side is 20 gpm and the "B" side 12, size for 20.

    Here is the piping for 2 boilers into a sep, if the 20 boilers are 20 gpm, a 1-1/4 would be close enough. No harm in going larger other than cost.

    Think of a 4 port hydraulic separator as two sets of closely spaced tees built into one pipe. A set of tees for the boiler side, a set of tees for the load side.

    If you were to build a sep, the barrel in the center needs to be 3 times the diameter of the piping into the sep. That give you
    adequate for the flows to pass through without any flow problems.

    Bob "hot rod" Rohr
    trainer for Caleffi NA
    Living the hydronic dream
  • stoke
    stoke Member Posts: 10
    Thanks for the response, Bob.
  • stoke
    stoke Member Posts: 10
    The gauge after the blender bugs me.
  • hot_rod
    hot_rod Member Posts: 22,022
    That is some nice piping work, a drain for the T&P, and back flow relief port, thermal drop to the mixer, probably the condensate drain, and maybe boiler relief, nice detail.

    Nice pipe bending, and well planned layout for all the piping.

    The gauge after the mixing valve is not very useful on a branch like that. You can buy gauge tailpieces now for those valves, puts the gauge right in the flow.

    And maybe the cir pump motor gets rotated to have electrical box facing up.

    Interesting "high water" stand for the indirect :)

    Who did the installation, I'd like permission to use the pic in my training ppts.
    Bob "hot rod" Rohr
    trainer for Caleffi NA
    Living the hydronic dream
    SuperJ
  • leonz
    leonz Member Posts: 1,095
    If your still in the planning stage why not use a steel compression tank and an airtrol valve sized for the two boilers and the systems gallon volume?
  • SuperJ
    SuperJ Member Posts: 609
    I'm impressed with the bending in Stokes picture, usually it's restrictive fittings everywhere or a mess of unsupported loopy, saggy pex.
    stoke
  • ratio
    ratio Member Posts: 3,615
    hot rod said:

    Who did the installation, I'd like permission to use the pic in my training ppts.

    High praise indeed.
    stoke
  • stoke
    stoke Member Posts: 10
    The “high water stand” is so I can get a broom in there.
  • stoke
    stoke Member Posts: 10
    I’m missing something from my Tekmar 306 to my boiler , DHW works fine. Any takers ?
  • Danny Scully
    Danny Scully Member Posts: 1,416
    How are you going to sweep under the stand @stoke ? :wink:
  • stoke
    stoke Member Posts: 10
    ...with a broom, of course. :p
  • leonz
    leonz Member Posts: 1,095
    stoke said:

    Short , fat , right ? The bigger the better ? If I understand this correctly, a min. size would be 1 1/2".

    ========================================================================================================================================================================================================================

    Have you looked at using and installing a steel compression tank with an airtrol valve large enough for both boilers to eliminate any trapped air in your designed system?

    I have a 15 gallon steel compression tank in my system with 10 gallons of water and 5 gallons of air capacity and I no longer have to bleed radiators nor do I have any trapped air in my 225 feet of 3/4 inch baseboard and I run it with very low pressures of 4-12 PSIG depending on how cold it is and how often my coal stoker has to work.
  • stoke
    stoke Member Posts: 10
    Hey lorenz, I should have labeled my drawing better. That’s a boiler with indirect. Your seeing the potable side , I went with some fancy Italian unit for the heat side of things.