As an example, consider a 1,200 ton chilled water CRAH deployment using all CMS equipment:
|Tons||EW||EA||LA||Approach||Chiller/ Pump kW||Fan kW||Net %|
|Chiller/ Pump kW||1,325|
|Chiller/ Pump kW||1,175|
The kW and percent comparison is net, including increased CRAH fan kW due to higher pressure drop of the lower-approach coil. This is the efficiency benefit during hours that the chiller is running.
In certain climates, there are further benefits to realize with higher water temperatures by increasing the number of hours that can be operated using a water side economizer. Also consider that, for new construction, the installation of air-cooled chillers also eliminates first-cost and field-work related to cooling tower installation and piping. Ongoing water and maintenance costs are also alleviated.