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spirovent or other

ecletrical Member Posts: 22
Because of piping considerations I can only used a Spirovent at the circ outlet (hottest water but highest pressure); or before the circ and before the boiler (lowest pressure but lowest water temp)

Which would you go for?




  • Jean-David Beyer
    Jean-David Beyer Member Posts: 2,666
    Do you know ...

    Do you know that Spirovent comes in models for vertical piping as wel las the more usual horizontal piping? Perhaps such a model might make it possible to put one of these vents in between the boiler and the circulator, so as to run hotter water through it.
  • ecletrical
    ecletrical Member Posts: 22
    there are 2 boilers,

    each with its own circ. The boilers and their respective circs never operate at the same time. Each circulator, when active, is also the system circulator.

    I could use 2 spirovents, or course, but want to get away with one.

    So which is more important for its effectiveness, low pressure, or hot water?
  • hot_rod
    hot_rod Member Posts: 22,266
    0n the hottest point,

    maybe the discharge of the boiler, given a choice.

    How are the boilers piped together, ideally locate it so it "purges" both boilers.

    Tie the expansion tank at the inlet side of the circ(s) not on the air purger if it is at the supply side of the boiler and the circs on the return side.


    Bob "hot rod" Rohr
    trainer for Caleffi NA
    Living the hydronic dream
  • Slimpickins
    Slimpickins Member Posts: 340
    What Hr said and ....

    In addition to what Hot rod said about the expansion tank on the inlet of the circulators (Pumping away) that is where you'd like to tie in the make up water as well. I would make a tee after the fill valve to both boilers so you always have 12 -15 psi at the PONPC. The air eliminator always works best on the outlet of the boiler where you see the hottest water where air comes out of solution. 
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