Answer - C - Chillers are devices that remove heat from a liquid, typically as part of a refrigeration system used to cool and dehumidify buildings. This liquid can then be circulated through a heat exchanger to cool air or equipment.
The cooling process begins when water enters the evaporator from the primary return—the evaporator transfers from the water to the refrigerant. The now-chilled water is then sent to the water tank via the primary supply, where it is distributed to the various climate-controlled spaces by the water pump. Because heat always moves from hot to cold, as stated by the second law of thermodynamics, the chilled water absorbs the conditioned space’s ambient heat in the air handler. A fan then forces the cooled air into the area via the ductwork. The warmer water is then returned to the chiller to cool again.
Meanwhile, the heat absorbed by the refrigerant in the evaporator is transferred to allow the refrigerant to absorb more heat. As a result, the low-pressure, high-temperature refrigerant moves from the evaporator to the motor-run compressor, increasing pressure and temperature.
After that, the refrigerant enters the condenser. Water-cooled chillers use water to surround the refrigerant pipes and draw in the heat (path shown in red). The water is then pumped into a cooling tower to release the heat. After condensing, the refrigerant goes through an expansion valve to reduce pressure (and temperature) before returning to the evaporator, where the process begins again.
