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radiant floor manifold/boiler manifold sizing

Jack_27 Member Posts: 1
A residential radiant heating system includes six tubing manifolds served by 1" supply and return piping. The boiler is a System 2000 EK-1 by Energy Kinetics. A radiant floor buffer tank {80 gal. hw tank} and a Taco 0011 circulator will provide the flow of tempered boiler water {further temperature reglation by a mixing valve} to the six tubing manifolds. Boiler supply and return piping is 1". Can the header from the buffer tank to the 1" tube manifolds be 1" also? How about the mixing valve? 1"? Thank you, jack


  • Al Letellier
    Al Letellier Member Posts: 781

    It depends on your heat load and flow requirement for the system. You have to know that before sizing the tubing. If you had a heat loss calc done, you should have that info.

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  • S Ebels
    S Ebels Member Posts: 2,322
    Ditto to what Al said

    it's all about flow rate and head. A 0011 is a lot of circulator unless your driving tubing lengths over 500'. I can't recall using anything larger than a 15-58 grundfos on any of our residential radiant jobs. We just lashed one up (thanks for the term Weezbo) this past week that has 9-300 ft loops of 1/2" pex. The pump is giving a nice 20* delta T on speed two. The one running the garage floor (4-300' loops) is handling them well on speed 1. Guessing is a waste of time, find out what you really need and go with it.
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