Which component is responsible for changing the refrigerant's pressure?

The component that specifically changes the pressure of the refrigerant in a refrigeration system is the expansion valve. This device is crucial in the refrigeration cycle as it reduces the pressure of the refrigerant before it enters the evaporator. In doing so, it allows the refrigerant to expand and cool down, enabling it to absorb heat from the surrounding environment in the evaporator.

The expansion valve operates by controlling the flow of refrigerant into the evaporator and ensures that the refrigerant is at a low pressure when it enters the evaporator coil. This change in pressure is essential for the refrigeration process, as it facilitates the absorption of heat and contributes to the overall efficiency of the system. Thus, the expansion valve plays a vital role in managing the refrigerant's pressure within the cycle.