Each building is cooled by two water-cooled units with scroll compressors to assure both maximum energy efficiency at part load operation and packaged design to shorten installation time. The chillers are connected with two dry coolers, where source side is coupled to reach low temperatures on glycol, when for example only one unit is running, or two units in partial load.

Source side is calculated at 45/40°C of 35% propylene glycol at ambient 35°C and set point on dry coolers (water outlet) is at 35°C. It is possible to go even lower in most of the time, but as user side is working at 15/20°C, it is close to the minimum differential ratio, in order to make the system more reliable.

As the outlet temperature on dry coolers can be 5K from ambient temperature and PHE freecooling exchanger is calculated with only 2K temperature approach, it is possible to run on 100% freecooling capacity under 8°C of ambient. As in winter time is needed only partial capacity, the “switching point” can be set at 12°C of ambient temperature.

Each unit is equipped with ModBus card and Ethernet connection. Main functions are still by wires, like ON/OFF, general Alarm etc., but each parameter and value are monitored by BMS.

To prevent failures, distributor have remote access by Ethernet and they can change everything in real time.