Why could a recycling or recovery machine with a hermetic compressor overheat when drawing deep vacuums?

A recycling or recovery machine with a hermetic compressor may overheat when drawing deep vacuums because the motor relies on refrigerant flow for cooling. In a hermetic compressor, the compressor and motor are enclosed within a single shell, and its design typically requires the circulation of refrigerant to help dissipate the heat generated during operation. When the machine operates at deep vacuum levels, the amount of refrigerant present is significantly reduced, which diminishes the cooling effect. As a result, the compressor runs the risk of overheating.

This relationship between refrigerant flow and the cooling of the motor is critical for ensuring efficient operation and preventing damage to the equipment. Recognizing this dependency emphasizes the importance of proper vacuum levels and the configuration of the recovery machine in relation to its operational environment.