What is typically the function of capillary tubes in an R22 refrigeration cycle?

Capillary tubes serve a crucial role in the refrigeration cycle, particularly in systems using R22 refrigerant. Their primary function is to control the flow of refrigerant between the high-pressure side and the low-pressure side of the system. By providing a fixed flow restriction, capillary tubes allow the refrigerant to expand and reduce its pressure as it enters the evaporator. This controlled flow is essential for maintaining the proper pressure differential required for efficient operation of the refrigeration cycle.

In systems where capillary tubes are utilized, they ensure that the correct amount of refrigerant enters the evaporator for vaporization, thus contributing to the cooling process. This mechanical process helps maintain the desired temperature and efficiency of the refrigeration unit.

The other options do not accurately represent the role of capillary tubes. Compressing refrigerant is done by the compressor, while releasing moisture pertains more to dehumidification processes rather than the function of capillary tubes. Increasing pressure is typically the function of the compressor as well, rather than the capillary tube which acts as a metering device.