Primary Pump Panels

We are a manufacturer and supplier of primary and secondary pump panels, Enable both primary and secondary chilled water pumps when outside air temperature is above set point and at least 1 chilled water coil control valve is open to coil. Modulate (vary) the speed of the secondary pump VFD to maintain a constant differential pressure. Enable chillers after flow is proven. Chillers operate to maintain leaving chilled water temperature at set point. Coil valves modulate to maintain comfortable space conditions.  When secondary pump speed is at minimum setting, bypass valve modulates to maintain secondary loop differential pressure. After pressure drops below set point and bypass valve is closed, pump speed will vary (increase initially) to maintain differential pressure.