from the system on the left of the diagram, producing low pressure there, and compresses it into the right half. As the ammonia boils off on the low-pressure side, it cools a jacket of brine (which has a low freezing temperature) that is circulated out to the task at hand—ice-making machinery in the case of an ice plant, or the refrigerated compartment of a ship. On the high-pressure side, the ammonia condenses, producing “waste” heat that is vented off.
