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Monoflow mess

Wayne55Wayne55 Posts: 10Member
I inherited this, one boiler wasn't doing job someone added other boiler.. basically 3 zones ( 3 circulators) can someone tell me how I can put the pics. From my phone on here please easier to show then ask my wuestion.been out of commission for about 5 yrs.


  • Wayne55Wayne55 Posts: 10Member
    Figured how to get pics. 3 floors,3 circs,seems 2nd and 3rd on one boiler,1st floor. On other boiler.but suppy and return are twin together .1st floor. Circulator seems to be pulling h/w from 2nd and 3rd floor.boiler.would it make sense to put check valve on return side so it can't pull h/w from boiler
  • IronmanIronman Posts: 4,964Member
    Your pics need to be from farther back showing as much of the piping as possible.

    The Grundfos circulator needs to be mounted completely horizontal, not half way vertical.
    Bob Boan

    You can choose to do what you want, but you cannot choose the consequences.
  • kevink1955kevink1955 Posts: 64Member
    I cannot make any sense of it but does anyone find it funny that a Hot Water system is piped in Black Iron. If only some of the new steam installers could do that instead of copper
  • GordyGordy Posts: 9,264Member
    ^It's probably because it's originally piped in black iron.
  • Wayne55Wayne55 Posts: 10Member
    It was originally piped in blk. Iron. I will get better pictures tomorrow. I was going to take that 1 inch line out put circulator completely on horizontal when I got call mother got rushed to hospital so I just slapped it in. I appreciate the feedback hopefully tomorrow I get better pics explain this mess better and I get some more feedback..thank you guys
  • Wayne55Wayne55 Posts: 10Member
    Hope these pics are better,couldn't move back any further . Ok there's 3 circs,3 relays,and 2 aquastats.whats happening is 3 floors,turn heat on 1 St floor and radiators on 3rd floor getting hot's a monoflow system .if these two boilers are connected what would prevent 1st floor. Grundfos coming on and pulling return water from other 2 zones
  • Wayne55Wayne55 Posts: 10Member
    Again I appreciate the feedback... This is pretty much volunteer work, it's a club for friends of bill w
  • DZoroDZoro Posts: 752Member
    That's messed up. Can you draw out the boiler piping layout.
  • Wayne55Wayne55 Posts: 10Member
    Just a heads up,I got run over my truck 4-5 yrs. Ago.screwed up my motor skills a little.cant draw straight.2 boilers tied together a off the main there's a 2x1 tee tieing into return.monoflow system,so I turn heat on 1st floor it's getting radiators hot on 2nd and 3rd floor .all circulators tie into return line not into boiler separately any suggestions
  • Wayne55Wayne55 Posts: 10Member
    Any suggestions guys besides find a new trade lmao.
  • DZoroDZoro Posts: 752Member
    Pretty much a re-pipe, download the OM, pipe it according to the manual. Have you done a heat loss, or radiation numbers? Do you really need 2 boilers?
  • Solid_Fuel_ManSolid_Fuel_Man Posts: 1,458Member
    You can keep the two boilers considering that they are already there. Just not the way its piped now! I'd also re-do the entire near boiler piping, pump away. I'd consider giving each boiler it's own pump and pipe it primarily/secondary. That way you can lead lag the boilers and have total redundancy for just the cost of two pumps.
    Master electrician specialising in boiler and burner controls, multiple fuel systems, radiant system controls, building controls, and universal refrigeration tech.
  • Wayne55Wayne55 Posts: 10Member
    Dzorro and fuel man sorry took so long to say thanks,after that mess I needed vacation. Repiped that cluster,rewired like a champ
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