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Monoflo system

DALE6 Member Posts: 10
Hi.  I am new to this forum. 

I am seeking advice about a monoflo system in my house.  Currently, there are fourteen loops running off a single main artery.  Two loops have been cut and capped.  Four are currently not producing heat.  I've tried several things, such as purge the air, but I still can't seem to get them to produce heat.  I'm wondering if the system has structural deficiencies.  For example, some of the loops have the diverter tee installed on the supply side, not the return side.  Is this a problem?  Another example, some loops have one or more loops within it.  Is this a problem?  Another example, some loops have two diverter tees but seem to only need one.  Is this a problem?  And this.  Some loops have tees that are only about twelve inches apart even though the radiation is well over ten feet long.  Is this a problem?  Thanks in advance for your help.


  • astoria2013
    astoria2013 Member Posts: 16

    I am assuming this is an old system that at one time worked fine.  I have run across this many times before in older installations.  Yes, it can be fixed if you pipe all monoflows correctly, but this is probably not needed.  99 percent of the time its a circulation problem.  Older jobs usually have a b&g 100 circulator on them and worked fine.  Well when the circulator goes, someone puts a mini circulator on.  Wrong...  you probably need a circulator that pump more GPH.  for example,  If you have a taco 007 or equivalent circulator, try upgrading to a 006 first before repiping whole system.   Of course it could also be many other problems, but given the info you gave, its worth trying this.  It could also be the pump is old and not circulating good anymore.  and remember, its not the size of the pump, its the GPH-Flow and Head-Feet that matter. 
  • NYplumber
    NYplumber Member Posts: 503

    a picture is worth a thousand words. Post pictures of the pump and the piping.
  • Paul48
    Paul48 Member Posts: 4,469
    edited January 2014

    The loops that have been cut and capped have to be piped as bypass. Cutting and capping adds huge restriction to the system.Standard installation put the diveter tee on the return. For more flow, put the tee on the supply. For maximum flow, and down-flow, use 2 tees.