If an Ammonia refrigeration system is concerned about water entrained within the Ammonia, what type of vessel could be used to help separate the water from the Ammonia?

The choice of an an-hydrator in an ammonia refrigeration system effectively addresses the concern of water being entrained with the ammonia. An an-hydrator is specifically designed to remove water from gases or liquids, ensuring that the ammonia is in a purer state, which is crucial for the efficient functioning of the refrigeration system. The presence of water can lead to inefficiencies and potential damage, as ammonia and water can react and lead to corrosion and other issues within the system.

In contrast, other types of vessels, like an oil still, are focused on separating oil from other substances, while an intercooler primarily cools refrigerant gases to enhance efficiency and reduce the risk of compressor damage. A low pressure receiver collects excess refrigerant but is not specifically designed to remove moisture from the system. Thus, the an-hydrator's ability to effectively separate water from ammonia makes it the correct choice in this context.