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Hrydonic system help. I’m at a loss.

Well guys I’m at a complete loss at what I’m doing wrong. I can’t maintain a .5gpm flow to keep my boiler lit. I’ve bled the system more times then I can count, not getting any more air out, removed the check valves on the pumps, opened all the lines all the way open, made sure my pump orientation and valve branch orientation are going to correct way. Any help on what I’m missing or doing wrong would be a small ray of hope before I trash this project with the biggest hammer I own. 

Comments

  • dirtman91386
    dirtman91386 Member Posts: 4

  • hot_rod
    hot_rod Member Posts: 22,105
    Some creative piping there!
    Looks like a tankless water heater, they typically need a high head circ.

    Good news, with those fittings you can disassemble easily and pipe like this drawing, give it a try. You may still need more circulator on the heater loop.
    One circulator does the boiler via the close tees, the other does the manifolds.
    Bob "hot rod" Rohr
    trainer for Caleffi NA
    Living the hydronic dream
  • Ironman
    Ironman Member Posts: 7,373
    Your piping and pump arrangement is wrong.

    Also: is that an instantaneous water heater? If so, you’ve got the wrong appliance. It has way too much head (resistance to flow) to be used in a hydronic system.

    You also are gonna have trouble with those Sharkbites allowing 02 diffusion.

    And the pumps must be mounted vertical.
    Bob Boan
    You can choose to do what you want, but you cannot choose the consequences.
    STEVEusaPA
  • Zman
    Zman Member Posts: 7,569
    If you just want this thing to "work" repipe it as hot rod has suggested. You will need to swing the the circs so that the shaft is horizontal.
    If you post the model number of the circ(s) and water heater, we can tell you if the circ sizing will work. The instruction manual for the water heater with resistance curve would help as well.
    "If you can't explain it simply, you don't understand it well enough"
    Albert Einstein
  • dirtman91386
    dirtman91386 Member Posts: 4
    edited December 2020
    So I mounted the circulation pump 90 degrees wrong?

    edit. This is for my garage flooring. Also Your drawing looks the same to me as my pump routing. 1 pump feeding manifolds and 1 pump pushing the boiler right? 
  • hot_rod
    hot_rod Member Posts: 22,105
    Here is what is going on with your piping. Flow out of the heater via the upper pump, drown thru the two tees, thru the second pump and back to the heater.
    There is no pump circulating to the manifold.

    The drawing I posted above has one pump for the boiler, the second for the manifold.
    Needs to pipe exactly like that. You're close, but not close enough.
    The upper boiler pump may need to be sized larger, try and see, if the heater goes into lockout or doesn't keep up with the heat requirement that may need to be upsized.
    The manufacturers don't always give you that pump requirement, because this is intended to be a water heater, not a boiler.
    As a water heater, water pressure in the building drives flow thru the heater, you are depending on a small pump to do that. It may not.
    Bob "hot rod" Rohr
    trainer for Caleffi NA
    Living the hydronic dream
  • dirtman91386
    dirtman91386 Member Posts: 4
    Its hard to see in the photo but It’s not 2 T’s. It’s a secondary loop purge T. zoom in on it. 

    Water comes out of the heater to the pump then goes to the branch then to the hot side manifold returns through the cold side manifold then goes back to the branch valve then to the 2nd pump finally returning water to cold side of the heater. 

    I have a flow right now of 2.2 gpm. There is an interior filter on the boiler that was pretty plugged debris. 
  • Ironman
    Ironman Member Posts: 7,373
    Here’s how you’re now piped:




    Bob Boan
    You can choose to do what you want, but you cannot choose the consequences.
    Canucker
  • Ironman
    Ironman Member Posts: 7,373
    edited December 2020
    Here’s how it should be:




    Notice where the system circulator is. 

    The way you have it, the circulators are in series, pumping only through the heater. Nothing will go to the system like that.

    As hot_rod mentioned, you’re gonna need a much larger Circ pumping the heater due to its high resistance to flow. Either a Grundfos ups26-99 or a Taco 013 at least.
    Bob Boan
    You can choose to do what you want, but you cannot choose the consequences.
    fenkel
  • Ironman
    Ironman Member Posts: 7,373
    edited December 2020
    Here’s a primary/secondary piping detail:


    The flow is reversed in this diagram from yours, but it's conceptually the same.
    Bob Boan
    You can choose to do what you want, but you cannot choose the consequences.
    Canucker