The receiver-drier’s primary function is to receive and store some liquid refrigerant from the condenser. The liquid refrigerant enters at the top of the receiver and falls to the bottom. A pickup tube with a filter screen extends to the bottom of the receiver-drier. This pickup tube draws liquid refrigerant from the bottom of the receiver-drier. The liquid refrigerant then passes on to the inlet of the thermostatic expansion valve.

Also like an accumulator, a receiver-drier serves as a temporary storage container for oil and refrigerant when not needed for system operation, such as during periods of low cooling demand. The receiver-drier also contains the system desiccant. This is the “drier” function of the receiver-drier.