What is the difference between air-cooled and water-cooled chillers, and in which cases each one should be preferred?

An air-cooled chiller has a condenser that is cooled by the environment air. The air-cooled chillers are preferred for small or medium installations but lately the quality improvement in their structure, allows the usage, in modular type, for large installations also. An air-cooled chiller is preferred especially in cases that there is not enough water or the water is very expensive. The water-cooled chillers have water cooled condenser connected with cooling tower and are usually preferred for medium and large installations where there is sufficiency of water. In addition, they are also preferred in cases that is demanded constant performance of the system, independently of the ambient temperature (industrial air conditioning, air conditioning of digital systems etc), because the capacity of the water-cooled chillers are not affected by the ambient temperature fluctuations.