Single stage systems without intermediate pressure vessel (Gustav Lorentzen process)

These systems have a low-pressure separator on the suction side that collects excess liquid at the outlet of the evaporator to protect the compressor from liquid slugging. The superheat is not controlled by the high pressure expansion valve.

The following points facilitate stable operation of the compressor during commissioning:

• Breaking the vacuum with gaseous R744 in the entire system up to approx. 40 bar.
• For water cooled gas coolers:
• Ensure water circulation.
• Check flow temperature.
• Set a constant high pressure set point on the gas cooler side, e.g. 80 bar.
• With water as the heat source on the evaporator side:
• Ensure water circulation.
• Check flow temperature.
• Switch compressors to "automatic mode" ready for operation and note that the controlled value for the capacity control of the compressors is temperature-controlled (hot water temperature), depending on the type of application.
• Further filling of the system, gaseous via the suction side.