What controls the operation of chilled water pumps?

The operation of chilled water pumps is primarily controlled by the chiller controller. This component is designed to monitor and regulate the entire chiller system, ensuring optimal performance and efficiency. The chiller controller takes inputs from various sensors throughout the system, including temperature and pressure readings, which allow it to determine the appropriate operation of the chilled water pumps. By managing the flow rates and adjusting the pump operation according to the cooling demand, the chiller controller plays a crucial role in maintaining the desired temperature within the system.

In contrast, while pressure sensors monitor the system's pressure and can signal when certain conditions are met, they do not directly control the pumps. Thermostatic expansion valves are critical for refrigerant flow regulation, but they do not interact with the chilled water pumps. Manual switches allow for basic on/off operation but do not provide the automated, demand-based control that ensures efficient system performance. Thus, the chiller controller stands out as the central element that coordinates the functioning of chilled water pumps within HVAC systems.