Ever had a zone pulse or bounce occasionally?

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Timco
Timco Posts: 3,040
in THE MAIN WALL
Back zone of my house. A couple times a month I hear an engine idling in the distance. It’s my back zone pulsing or bouncing. Good x tank, 15-58 med speed. Changing anything quickly stops the phenomenon.

Thoughts? It’s strapped tight.
Just a guy running some pipes.

Comments

  • Solid_Fuel_Man
    Solid_Fuel_Man Posts: 2,644
    15-58 got an IFC? Is there also a flow check in the circuit? What is your deltaT with it on low speed?
    Serving Northern Maine HVAC & Controls. I burn wood, it smells good!
  • hot_rod
    hot_rod Posts: 28,511
    TRV on the circuit? sometimes they will pulse. Agree with the integral check valve in the circulator, it could be causing some pulsation on low flows.
    Bob "hot rod" Rohr
    trainer for Caleffi NA
    Living the hydronic dream
  • Timco
    Timco Posts: 3,040
    Actually there is a FC in it and I put a spring check on returns to keep zones flow separated. Remove return spring check?
    Just a guy running some pipes.
  • hot_rod
    hot_rod Posts: 28,511
    The spring checks, were they hydronic type? Checks can have different "pop"or cracking pressure. Here is a common Conbraco soft seat check used for hydronics, notice the different pop pressures available.

    I think those checks in the circulator are somewhere between .35 and .50 psi crack. if you get too stiff of a spring the valve may hunt around causing the surge.

    Ideally when sizing a check use the flow rate not pipe size, often the check can be a few sizes smaller then the piping.

    Also know the Cv is with the check full open. If you have too much spring the check will possible rattle and also add some pressure drop, maybe turbulance if it in a partially open positions .



    Bob "hot rod" Rohr
    trainer for Caleffi NA
    Living the hydronic dream

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