How are hermetic compressors typically cooled?

Hermetic compressors are typically cooled by superheated refrigerant vapor. The design of hermetic compressors ensures that they are sealed units, which means that the refrigerant remains inside the compressor without any exposure to the atmosphere. In operation, the refrigerant vapor coming from the evaporator is compressed and heated during the process. This superheated vapor not only powers the refrigeration cycle but also plays a role in cooling the compressor itself.

As the compressor works, the superheated vapor helps to absorb some of the heat generated by the motor and the compression process, maintaining a stable operating temperature and preventing overheating. This method of cooling is efficient because it utilizes the very refrigerant that the compressor is pumping, allowing the unit to manage its own temperature through the heat exchange between the refrigerant vapor and the compressor components.

Other cooling methods mentioned, such as ambient air, chilled water, and liquid refrigerant, are not typically used in hermetic compressor designs due to their closed system nature and the specific operational requirements of these compressors. Using superheated vapor for cooling is an integral part of their design and function.