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Primary/Secondary looping for multi-temperatures

Hello All, this is my very first post and first go @ setting up a multi-temperature system.


Primary loop Circulator -
Taco 007 (7.82 gpm; Head Added 10.51ft; Diff. Press 4.43)
Secondary loop Circulator(s) -
Taco 0014 (10.06 gpm; Head Added 16.34; Diff. Press 6.89)
Taco 008 (7.82 gpm; Head Added 10.51ft; Diff. Press 4.43)
-Issue-
When stat calls for heat in Secondary loop(s) (middle or top manifold) primary loop and secondary zone loop circulators start. Heat is properly mixed thru 4-way set point; HOWEVER temperature between post mix valve gauge and manifold gauge is different (-40 degrees).
Is the primary loop circulator on the wrong side of the T's (could they be fighting each other), incorrect type of flow check valve, incorrect zone circulator (system has 22-25 psi)?
All constructive input and questions are welcome. (Have lots of data)


Primary loop Circulator -
Taco 007 (7.82 gpm; Head Added 10.51ft; Diff. Press 4.43)
Secondary loop Circulator(s) -
Taco 0014 (10.06 gpm; Head Added 16.34; Diff. Press 6.89)
Taco 008 (7.82 gpm; Head Added 10.51ft; Diff. Press 4.43)
-Issue-
When stat calls for heat in Secondary loop(s) (middle or top manifold) primary loop and secondary zone loop circulators start. Heat is properly mixed thru 4-way set point; HOWEVER temperature between post mix valve gauge and manifold gauge is different (-40 degrees).
Is the primary loop circulator on the wrong side of the T's (could they be fighting each other), incorrect type of flow check valve, incorrect zone circulator (system has 22-25 psi)?
All constructive input and questions are welcome. (Have lots of data)
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Comments
Edit: However I believe you can orient them as such so long as system psi is 20, or more? I don’t know why it’s that high though. Best to have motor horizontal. Gets air out of the volute much easier.
The way you have it with two circs involved in the primary loop the flows are not predictable, or consistent depending on when, and how often that high temp zone comes in line.
https://www.caleffi.com/sites/default/files/coll_attach_file/idronics_1_0.pdf
primary loop pump is much lower gpm than secondary pumps. This will make the water flow backwards through the "cross over bridge" and probably cause your temperature to be different from what you expect.
The tees to your high temp zone are incorrectly oriented to the primary loop and incorrectly oriented to your radiant loop low temperature zone
The high temp loop is not piped right. You should only have one circ in the primary loop. You essentially have two. The way it is piped with the high temp loop circ dumping in down stream of the primary loop circulator inside the primary loop. This essentially renders the primary loop concept useless.
Any zones off the secondary loop need to be teed off the secondary loop, or another set of closely spaced tees off the primary loop.
To the OP are you saying you are getting 120 after mixing valve then 80 at the temp gauge on the supply manifold, and then 80 on the return manifold?
STEVEusaPA - Orientation (upside down) ? Do you mean Vertical not horizontal like they are? or do you mean rotated so motor is to the side of the pipe?
Gordy - see last response.
EBEBRATT-Ed - Great point about the T orientation to the primary loop. I tried tying into the existing setup to create the primary loop. see simple diagram
Paul48 - hmm. that's what the gauges say... and tested ok.
Gordy
1. They are horizontal or maybe this is the same statement as Steve.
2. Technically there is only (1) one Circulator in the Primary; I will tempt to address this using simple diagram
3. Caleffi - fantastic paper; thanks!!!
4. This by far was the most insightful comment; unfortunately I'm a little confused as you can see. With my current setup could you give me a simple sketch that would give me the proper piping layout?
Simple Diagrams:
Original piping setup-
Current piping setup-
* I've closed off High Temp zones with no successful change in temperature flow (back to thinking its the circulating pump for the manifold zones; aka incorrect orientation) Is there a recommended pump that is built for that orientation?
Here's what I've found from searching other equipment manufacturers.
I will try tomorrow and post results.
BTW: does anyone know how to flip the mechanisms around on a 4-way mixing valve? It seems that Taco also likes to design to the left <...
However I don't see how you can get 80 supply, and 80 return. With 120 water. Unless the radiant room temp is 80 degrees allowing for zero delta t supply, and return, or zero flow with the ambient in the boiler room is 80 degrees.
I'm thinking air may be your issue.
trainer for Caleffi NA
Living the hydronic dream
If all those circulators are running at the same time you loose your hydraulic separation.
Looks like you also have your P/S connection as a reverse injection?
A few repiping details would give you a more predictable piping system.
trainer for Caleffi NA
Living the hydronic dream
That adds some confusion. He's working with the 4-way, and has it piped per the instructions, on the secondary side, anyway. Evidently the valve may be installed backwards?
trainer for Caleffi NA
Living the hydronic dream
Ok got it!!! Indeed having the circs in that position and airlock was the problem.
Now time to tweak..
I'm getting the proper flow and heat thru my larger (lower) manifold; as expected 180 F to 4-way > 130 F to larger manifold return @ 120 F !!!
Having trouble getting the flow thru the smaller (top) manifold??
I'm thinking of changing the piping layout.. Based off of your guys suggestions and reading much more about hydraulic separation... What do you guys think of this sketch? Each Circ will be controlled by individual stat...
Here is some more information that I had found in regards to P/S calculations.
https://www.slideshare.net/illinoisashrae/hydronic-basics-primarysecondardy-pumping