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Backflow preventers

Mike Member Posts: 94
Does anyone know if one backflow preventer can feed two different boilers? Can't find any code that stipulate this.


  • Zman
    Zman Member Posts: 7,607
    Are you talking about 2 separate closed loops systems? I don't think it is against code. I is not very practical as the systems would share the same water. A leak in one would result in a leak in the other.
    "If you can't explain it simply, you don't understand it well enough"
    Albert Einstein
  • hot_rod
    hot_rod Member Posts: 22,483
    It would see both boilers as one system, unless you added additional checks on both, expansion tanks also.

    Same as a single BFD on the main house line feeding multiple connections downstream, I suppose.
    Bob "hot rod" Rohr
    trainer for Caleffi NA
    Living the hydronic dream