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Taco PC705, Has anyone used this? give details how.
Quoted from taco "PC705: VARIABLE SPEED PUMP INJECTION MIXING CONTROL
The Taco Mixing Control regulates the supply water temperature to a heating system by simultaneously controlling a boiler and the speed of an injection pump. Based on the outdoor air temperature, the PC705 continuously
adjusts the boiler differential to optimize the firing cycles of the boiler, prevent large water temperature swings, and increase the efficiency of the system. As the heating load increases, the Mixing Control speeds up the
injection circulator and as the load decreases it slows down the injection circulator. The Mixing Control features full diagnostics including a lighted bar graph that simulates the speed of the variable speed injection pump,
warm weather shut down, a maximum supply water temperature setting, and a boiler sensor that can be connected in order to prevent corrosion in the boiler due to flue gas condensation."