RETA Certified Assistant Refrigeration Operator (CARO) Practice Exam 2025 – The All-in-One Resource for Exam Success!

An accumulator's primary function in a refrigeration system is to collect and store excess liquid refrigerant. This is particularly important in systems where refrigerant flow can cause a mixture of liquid and vapor to transition through the compressor. The accumulator ensures that only vapor is delivered to the compressor, preventing potential damage that could occur if liquid refrigerant were to enter. By balancing the refrigerant flow, it helps maintain system efficiency and reliability. This characteristic is essential for allowing proper operation, ensuring the compressor does not suffer from hydrolock, which can occur if liquid refrigerant is accidentally introduced into the compressor.

The other functions presented do not accurately describe the role of an accumulator. While cooling the refrigerant before it enters the evaporator or filtering contaminants are essential processes in a refrigeration system, these are not functions of the accumulator. Instead, those tasks are typically managed by other components within the system, such as the evaporator or filters. The release of pressure during the cooling cycle is also not a primary function of the accumulator; instead, pressure management is a general aspect of system performance across various components.