Compressor having external shell with vibration isolation and pressure balance

A screw compressor, comprising:

• a screw compression mechanism, the screw compression mechanism having a first pressure side and a second pressure side;
• an external shell, the external shell configured to enclose the screw compression mechanism, and the external shell including a first compartment, a second compartment, and a third compartment, the first compartment being in fluid communication with the first pressure side, the second compartment being in fluid communication with the second pressure side,
• the third compartment encloses a first portion of the screw compression mechanism,
• the second compartment encloses a second portion of the screw compression mechanism,
• the first portion and the second portion of the screw compression mechanism are oppositely located, and a pressure in the second compartment and a pressure in the third compartment are balanced;
• a first seal fluidly separating the first compartment and the second compartment;
• and
• a second seal fluidly separating the first compartment and the third compartment,
• the second seal secured to the external shell and the second seal secured to the screw compression mechanism, thereby forming the third compartment,
• wherein the screw compression mechanism is isolated from the external shell by an isolator secured to the external shell and to the screw compression mechanism, wherein the isolator is configured to reduce vibration transmitted from the screw compression mechanism to the external shell, and
• wherein the first seal is physically separate from the isolator.