In order to improve the operational reliability of a refrigerant compressor system that includes a first refrigerant line that conducts expanded refrigerant, a second refrigerant line that conducts compressed refrigerant, at least one refrigerant compressor that is arranged between the first and the second refrigerant line and is driven by a motor, and a control unit for operating the refrigerant compressor system, it is proposed that the control unit should have a first central processing unit and at least one input/output unit for control variables that communicates with the first central processing unit, and that there should be associated with the first central processing unit a second central processing unit which, in the event of a failure of the first central processing unit, takes over the control functions for the purpose of controlling the refrigerant compressor system.