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Is this functionally the same as closely-spaced tees?

rsilvers
rsilvers Member Posts: 182

Does this work for primary / secondary? Is some reason why someone did it like this?

I have only see closely-spaced tees. Will this kind of connection work the same way? 

It’s a bit like how a hydro separator is oriented. 


Comments

  • mattmia2
    mattmia2 Member Posts: 9,572
    It is a bypass, probably to guarantee the minimum flow through the boiler when only the smallest zone is calling but we would need to see more piping from further back to say why for certain.
    HomerJSmith
  • rsilvers
    rsilvers Member Posts: 182
    It’s just that I see a pump on the boiler side and then a pump for each zone. So that makes me think it is a primary / secondary system.


  • Ironman
    Ironman Member Posts: 7,366
    No, it’s a bypass which is totally unnecessary on a mod/con; in fact it defeats its design purpose of wanting the coolest return water temp for maximum efficiency.
    Bob Boan
    You can choose to do what you want, but you cannot choose the consequences.
    PC7060
  • Zman
    Zman Member Posts: 7,561
    What you have is some very nice workmanship performed by someone who does not understand primary/secondary and who has a serious pump addiction.
    Its probably not so bad that it needs "sawzall therapy". IMO, if you open that valve all the way, you will have workable hydronic separation. I would feel the pipes above the circulators when only one zone is calling to make sure the boiler circ is not "ghosting" the zones that are not calling.
    "If you can't explain it simply, you don't understand it well enough"
    Albert Einstein
    Derheatmeister
  • TAG
    TAG Member Posts: 755
    Holy pumps Batman
    HomerJSmithDerheatmeister
  • jad3675
    jad3675 Member Posts: 127
    I kinda' curious as to what wireless thermostats are installed on that system.
  • Ironman
    Ironman Member Posts: 7,366
    A Caleffi Sep4 low loss header looks like it would fit nicely in there and give dirt removal and air separation while  accomplishing  hydraulic separation.


    Bob Boan
    You can choose to do what you want, but you cannot choose the consequences.
    mattmia2
  • Ironman
    Ironman Member Posts: 7,366
    What’s the purpose of the strap on aquastat?
    Bob Boan
    You can choose to do what you want, but you cannot choose the consequences.
  • hot_rod
    hot_rod Member Posts: 22,018
    Ironman said:

    A Caleffi Sep4 low loss header looks like it would fit nicely in there and give dirt removal and air separation while  accomplishing  hydraulic separation.


    A textbook installation of a separator, nice!
    Bob "hot rod" Rohr
    trainer for Caleffi NA
    Living the hydronic dream
    Ironmanmattmia2
  • mattmia2
    mattmia2 Member Posts: 9,572
    Ironman said:

    What’s the purpose of the strap on aquastat?

    There is at least one circulator I can't at all guess what it might be doing.
  • HomerJSmith
    HomerJSmith Member Posts: 2,425
    Interesting, velly, velly, interesting. You need help by a hydronic specialist.

    You can discuss with your hydronic specialist whether closely spaced tees or a hydro sep is in your future.
  • hot_rod
    hot_rod Member Posts: 22,018
    edited March 2022
    Maybe that boiler has a second set of S&R for piping an indirect? That may be why the two circs under the boiler?

    Primary/ secondary should be explained as aka closely spaced tees or a hydraulic separator devices. I don't see either in that piping?

    What you have is a direct piped boiler. Also, your boiler pump is in series with the zone pumps, so doubling the head. But with all those zone pumps I'm not sure what head you see as they rotate on and off.
    I suspect with one or two zone pumps calling you have some fairly high flow velocities. Noise?
    Perhaps the bypass mitigates some excessive zone flows. Wonder what the adjustment procedure is?

    Does the installation manual show that piping option?
    https://s3.amazonaws.com/s3.supplyhouse.com/product_files/CHS-110-slantfin-install.pdf
    Bob "hot rod" Rohr
    trainer for Caleffi NA
    Living the hydronic dream
  • mattmia2
    mattmia2 Member Posts: 9,572
    hot_rod said:

    Maybe that boiler has a second set of S&R for piping an indirect? That may be why the two circs under the boiler?

    But it also sort of looks like it is a combi and has a dhw recirculation pump.

    hot_rod said:


    Perhaps the bypass mitigates some excessive zone flows. Wonder what the adjustment procedure is?

    I suspect the original installer was using those gauges to adjust it, still not sur if they were a genius and it makes sense if you knew what was happening in their head or if they just kept adding stuff on until everything was connected.
  • HomerJSmith
    HomerJSmith Member Posts: 2,425
    Some pics of the boiler close ups of the pump piping and some pics further away of the manifold piping would be helpful.

    You don't have a primary/secondary sys. You have a conflict between the boiler pump and the manifold pumps.

    With that boiler I would want a separation between the boiler sys and the load sys. Get rid of that crossover. That ball valve is the wrong type of valve, anyway for a bypass. It probably has low valve authority. Under other circumstances a 1/2" globe valve would have been adequate. Just my thinking.