Final answer:
Under normal operating conditions, refrigerant entering the compressor is in a vapor state. The compressor raises its temperature and pressure, allowing for heat transfer when it reaches the condenser coils and condenses into a liquid. After passing through a pressure-reducing valve, the liquid cools and absorbs environmental heat, completing the cycle.
Step-by-step explanation:
Refrigerant that enters the compressor, under normal operating conditions, is in a vapor state. The operation of the compressor in a refrigeration cycle is to raise the temperature and pressure of this vapor. When the refrigerant vapor is compressed, it increases in both temperature and pressure which allows it to transfer energy via heat transfer to the surroundings in the condenser coils.
Following the increase in temperature and pressure, the vapor enters the condenser coils, typically located inside the heated space (for example, within a room that needs heating or outside of the refrigerator in a cooling cycle). Once the refrigerant, which now has a high temperature, passes through the condenser, it loses heat to the cooler indoor air and condenses into a liquid.
The now-liquid refrigerant then travels back through a pressure-reducing valve before returning to the outdoor evaporator coils. In the evaporator, the pressure of the refrigerant is reduced, which causes it to cool down as it expands. This cooler liquid can then absorb heat from the surrounding environment (inside of the refrigerator or the room to be cooled), starting the cycle once more.