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P/S Max GPM?

Blackoakbob Member Posts: 252
That's what I'm after, I will check out Taco, thanks. My plan is to tie three boilers to an existing system via the hydro separator. Your project sounds great. What did you use for boilers,if I may ask. Best regards, blackoakbob


  • Blackoakbob
    Blackoakbob Member Posts: 252
    P/S Max GPM?

    Is there a maximum gpm limit on primary/secondary? I planning a job that may require 150 gpm total when all of the modcons are on. Also, would there be a significant PD across the IE. Caleffi unit? Thanks in advance. Best regards, blackoakbob
  • Brad White_185
    Brad White_185 Member Posts: 265
    No Limits

    The principle of P/S piping is just that, a principle. It does not bow to size.

    FWIW, I have recently completed a P/S system using two boilers handling 358 GPM each, feeding into a common HW system system with variable flow. Not a problem.

    Oh, if you are looking for a larger flow rate low loss header, Taco has a line, 5900, which goes up to, well, name it pretty much, at least 12 inches, if memory serves.
  • Brad White_187
    Brad White_187 Member Posts: 13
    Hi Bob

    The boilers were gas-fired Burnham V-1118's serving an elementary school formerly served by a 1956 Fitzgibbons fire-tube steam boiler.

    I am now looking at retrofitting a series of five Aerco Benchmarks (2.0 MMBH input each, 90 GPM each) using a Taco hydronic separator. System was supposedly P/S but not really.... :P

    The Taco unit in that size should be a neat fix, I think.
  • Paul Rohrs_7
    Paul Rohrs_7 Member Posts: 173
    12\" Taco Green Hydroseparator?

    Sounds like a giant Hydronic sepository for proper flow.

  • Kal Row
    Kal Row Member Posts: 1,520
    the caleffi hydro seperator is avail in 6\" and 8\"

    it's almost always the better way to do this - the bell and gossett people took one look at the Caleffi and they are selling it under their label - (they paint the non insulated ones red ;) i suspect many others will follow, it just makes sense and when you think about the air and dirt separation effect combined with this huge point of zero pressure change, it also makes “dollars”, – not to mention the fact that to do close-T’s correctly, you need 6 primary pipe diameters on either side of the tees – a bit long with 4” pipe
  • Blackoakbob
    Blackoakbob Member Posts: 252
    Couldn't fird..

    the Taco hydroseparator on the Taco website last night. I'll check again tonight. Are they calling it a "hydronic bridge"? I haven't been able to locate a local ( Minnesota) rep for Caleffi, most of the sales people say, "Who?"
    Are they usually sized by the pipe size or gpm?
    Best regards,
    Happy Mother's Day!
  • hot_rod
    hot_rod Member Posts: 22,251
    Caleffi has

    supplied 10 and 12". I believe we have a 16" in the works for a special order. Your local rep or dealer should be able to get a price for you.

    hot rod
    Bob "hot rod" Rohr
    trainer for Caleffi NA
    Living the hydronic dream
  • Todd S_8
    Todd S_8 Member Posts: 26
    Taco 5900 Series

    Hydrolic Seperator - here is the link:

This discussion has been closed.