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How Close Can I!

Rich Davis_2
Rich Davis_2 Member Posts: 101
How close can I place the suction side of a 008 a Taco 4900 air sep.  Siggy talks about having 10 pipe dia. from a Elbow, would this be the same or can I get by with less distance.  Thanks


  • Mark Eatherton
    Mark Eatherton Member Posts: 5,837
    Let them kiss if you can....

    Or just hold hands if you are so inclined...:-)

    You can't have the pump too close to the PONPC (expansion tank) but obviously need isolation valves, nipples etc.

    If you are using a regular scoop type air eliminator, some manufacturers call for straight pipe BEFORE the separator, but if you are using a micro bubble resorber type, no straight pipe minimum requirement before or after.


    It's not so much a case of "You got what you paid for", as it is a matter of "You DIDN'T get what you DIDN'T pay for, and you're NOT going to get what you thought you were in the way of comfort". Borrowed from Heatboy.
  • Rich Davis_2
    Rich Davis_2 Member Posts: 101
    It's more about the circ.

    Mark thanks for your reply,

    My concern was about not having laminer flow to the circ, would the 4900 seperator cause enough turblence to cause the circ to cavitate.  Sorry I didn't make it clear enough.
  • Brad White
    Brad White Member Posts: 2,393
    edited January 2011
    By the time

    the water leaves the 4900, the air is gone and turbulence should be minimal. As Mark said, an upstream isolation valve (full port) is a good idea anyway and affords additional length. I also would not reduce it. For example, if your 4900 is 1.25" then so should your piping up to and including the pump flange.

    The 4900 itself has no minimum upstream nor downstream restrictions per the literature.

    My own boiler now has a 4900 screwed on the male outlet of a street el and immediately downstream of the 4900 is an isolation flange with drain, then a Wilo Stratos Eco as my boiler circulator, all piped 1.25". Works great even from first start-up/first pass.

    Yes, the isolation valve is a chaperone between the Taco 4900 and the Wilo circulator. As much as I agree with ME, there is still something illicit about forbidden love in hydronics. :)
    "If you do not know the answer, say, "I do not know the answer", and you will be correct!"

    -Ernie White, my Dad
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