The compressors are used for two classes of cooling systems are named:

• LST - Low Starting Torque, used in capillary systems.
Ex: Refrigerators, Freezers, Commercial Counters, Drinkers and Refreshers.
• HST- High Starting Torque, used in systems with conventional expansion valves.
  Ex .: Commercial Counters, Exhibitors, Butcher Refrigerators and Refrigerating Chambers.