Aim of Project

Currently Free Cooling is usually implemented by means of an intermediate circuit of a cooling medium.  Aim of the project was the development of a Free Cooling process as a refrigerant circulating system (analog heat pipe principle), but without such an additional intermediate circuit. In that way the annual share of Free Cooling could increased by approximately 20%. Primarily this is the effect of non-use of intermediate circuit.

Results

The aim of the project was achieved. A Free Cooling process with pump circulation of refrigerant was developed. For this a common refrigerant circuit is expanded substantially by a vertical pipe (refrigerant collector) and a refrigerant pump. For ecological but also technical reasons CO2 is used as refrigerant in this circuit. A prototype was constructed. Measurement tests were performed. The function of this Free Cooling system was demonstrated. The change over switching between the compressor operation and Free Cooling operation was successfully tested. A variety of measurements were carried out.