Why must water be circulated through a chiller during refrigerant evacuation?

During refrigerant evacuation, circulating water through a chiller is crucial to prevent the freezing of water within the system. When a chiller is evacuated, the pressure inside decreases, which can lead to the freezing point of water being reached, especially if the temperature is low enough. If the water were to freeze, it could lead to ice formation within the chiller, potentially damaging components and obstructing the usual flow of refrigerant.

Thus, maintaining a constant flow of water helps to regulate the temperature and ensures that it stays above freezing. This is particularly important in systems that may operate in environments where temperature fluctuations can lead to the risk of freezing, ultimately protecting the integrity of the chiller and maintaining operational efficiency.