Free-cooling chillers

Free Cooling operation system in more depth

When all year long water cooling is required, a free cooling chiller is certainly the right choice as the efficiency of this system is, on average, much higher than a traditional water chiller. The cost of this system is easily recouped in a short time, with big environmental benefits. Obviously the best application of a free cooling chiller is on a cooling system where the required chilled water temperature is higher than usual for air conditioning applications. It is particularly suited for industrial process cooling and computer suite/ data centre air conditioning.

The operation of the free cooling system consists of finned pack heat exchangers placed in front of the condensing coils. Air flows through the water coils before crossing the condensing coils. When the outdoor temperature is lower than the returning water temperature, the free cooling system can operate. The free cooling efficiency (EER) depends on the temperature difference between the ambient and desired chilled water temperature (EER is higher than the water/air delta temperature increase).The chiller can operate under three main conditions: Mechanical cooling_Ambient temperature is higher than the returning water temperature. Partial free cooling_Ambient temperature is lower than the returning water temperature.Total free cooling_Ambient temperature is lower than the returning water temperature at least 6°c.

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