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dual pumps

I am thinking about running a Primary- Secondary circulator system for my radiant slab heat. I plan on using 3 pumps. One on the primary "return" loop, one on the secondary" supply "and one on secondary "return". Has anyone ever set one up like this before?

Comments

  • Jamie Hall
    Jamie Hall Member Posts: 22,916
    A pump on the return and a pump on the supply? No need. In fact, not really desirable at all. Put one pump of the correct size on the supply side. A pump on the return would have low pressure at its inlet -- and the pressure might be low enough to cause cavitation and a lot of noise, as well as destroying the pump. Not a good idea.
    Br. Jamie, osb
    Building superintendent/caretaker, 7200 sq. ft. historic house museum with dependencies in New England
    hollywood7445IronmanCanuckerRich_49
  • hollywood7445
    hollywood7445 Member Posts: 2
    I have 5 x 300' loops of 5/8 I.d. pex going to a manifold. I was going to use a 1/25 hp Taco pump.
  • Jamie Hall
    Jamie Hall Member Posts: 22,916
    You need a pump to circulate water through the manifold and radiant slab and mixing valve. You need a pump (I'm presuming this is p/s) to circulate through the boiler. End of story.

    Figure pump sizes (the boiler probably has a recommended pump) based on flow and headloss
    Br. Jamie, osb
    Building superintendent/caretaker, 7200 sq. ft. historic house museum with dependencies in New England
    Ironman
  • Rich_49
    Rich_49 Member Posts: 2,766

    I have 5 x 300' loops of 5/8 I.d. pex going to a manifold. I was going to use a 1/25 hp Taco pump.

    Which 1 / 25th HP circ were you going to use ? There's a few
    You didn't get what you didn't pay for and it will never be what you thought it would .
    Langans Plumbing & Heating LLC
    732-751-1560
    Serving most of New Jersey, Eastern Pa .
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    Rich McGrath 732-581-3833