A liquid receiver is used for what purpose?

The liquid receiver plays a crucial role in a refrigeration or air conditioning system by storing liquid refrigerant. It acts as a reservoir that collects refrigerant after it has been condensed in the condenser. This is important because it ensures that the system has a sufficient supply of liquid refrigerant available for the expansion device to function properly.

Storing the liquid refrigerant allows the system to accommodate variations in refrigerant flow and helps avoid flooding the compressor, which can occur if there is an excess supply of liquid. Thus, the liquid receiver effectively maintains the balance between the liquid and vapor refrigerant in the system, ensuring optimal and efficient operation.

In contrast, the other options relate to different functions within the system. Converting vapor to liquid pertains to the condenser's role in refrigeration, facilitating expansion is associated with the expansion valve or device that reduces refrigerant pressure, and isolating the compressor refers to components that might minimize the pressure fluctuations experienced by the compressor but is not a function of the liquid receiver itself.