Do you have good quality water available ? Does it cost money to get water ? In many parts of the world, water is a scarce commodity.
When you compare air and water cooled chilles, an overall system cost (both running and installed) has to be worked out. Also, the type of application, the ambient conditions (wet bulb and dry bulb), number of hours of operation, part load pattern, cost of maintenance, etc., play a role in this decision.
There is no single answer to this question - Water-cooled is better or air-cooled is better. It depends.
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