Mixing loop, double shunt with 3-way valve, type 2

A double shunt mixing loop is characterised with constant flow on the primary side which is causing high pumping energy costs. A double shunt mixing loop is normally fitted with a 3-way valve.

A double shunt mixing loop is characterised with constant flow on the primary side which is causing high pumping energy costs. Double shunt mixing loops should not be used unless there is a demand of constant temperatures on the primary side due to very extensive distribution pipes. Keeping up temperatures can also be achieved in a cheaper way by establishing a by-pass at the pipes farthest point. A double shunt mixing loop is normally fitted with a 3-way valve.

  • Secondary side:
    The load will normally be a heat surface or a radiator system where there is a demand for a variable temperature.
    Due to a reduction in the flow temperature, the flow in the secondary side will normally be higher than in the primary side.
    The flow can be constant or variable, depending on the system.
    The valve can be placed either in the flow pipe or in the return pipe.
  • Primary side:
    The flow is constant, but the differential temperature will change when the valve is adjusting.

Interaction with speed-controlled pumps:

  • Secondary side:
    Due to the higher flow in the secondary side, a speed-controlled pump will have the authority in secondary systems.
  • Primary side:
    A pressure-controlled pump will not react when the valve is adjusting, but it is possible to employ speed control on the pump based on temperature, constant return temperature or constant differential temperature.




    Facebook Twitter LinkedIn Technorati