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is there any advantage in using a small buffer tank instead of a low loss header?

john123 Member Posts: 74
anyone guide me here--please.


  • GroundUp
    GroundUp Member Posts: 1,909
    Both could create hydraulic separation, as could a hydraulic separator or even closely spaced tees, but unless there is a need for added mass, a buffer serves no purpose beyond hydraulic separation.
    Mad Dog_2
  • clammy
    clammy Member Posts: 3,112
    I have used boiler buddy buffer tanks on one or two mod con that where mirco zoned to prevent short cycling which it did . I ll always look at the job and the output of each zone and the lowest modulation of the boiler when thinking about buffer tanks or if doing mix temps where there is mirco zoned radiant then having a buffer tank really makes sense .
    Peace and good luck clammy
    R.A. Calmbacher L.L.C. HVAC
    NJ Master HVAC Lic.
    Mahwah, NJ
    Specializing in steam and hydronic heating
    Mad Dog_2
  • hot_rod
    hot_rod Member Posts: 22,158
    Any amount of added volume will lengthen the on cycle. You can use a formula to determine the “time”
    with a mod con, compare the lowest turndown to the btu of the smallest zone or load

    Tank can be much smaller for modulating type devices, heat pumps and boilers

    Ive done a few 6 gallon electric he tanks as buffers to get me over a 10 minute run time with micro loads like bathroom zones

    It just depends on your goals
    Bob "hot rod" Rohr
    trainer for Caleffi NA
    Living the hydronic dream
    Mad Dog_2