period one
Types of Water Chillers
notes
air-cooled or water-cooled
Comparison
air-cooled | water-cooled |
▲ | Lower maintenance | ▲ | Greater energy efficiency |
▲ | Packaged system | ▲ | Longer equipment life |
▲ Better low-ambient operation
Figure 13
Another advantage of an air-cooled chiller is its delivery as a “packaged system.” Reduced design time, simplified installation, higher reliability, and single-source responsibility are all factors that make the factory packaging of the condenser, compressor, and evaporator a major benefit. A water-cooled chiller has the additional requirements of condenser-water piping, pump, cooling tower, and associated controls.
Water-cooled chillers typically last longer than air-cooled chillers. This difference is due to the fact that the air-cooled chiller is installed outdoors, whereas the water-cooled chiller is installed indoors. Also, using water as the condensing fluid allows the water-cooled chiller to operate at lower pressures than the air-cooled chiller. In general, air-cooled chillers last 15 to 20 years, while water-cooled chillers last 20 to 30 years.
To summarize the comparison of air-cooled and water-cooled chillers, air-cooled chiller advantages include lower maintenance costs, a prepackaged system for easier design and installation, and better low-ambient operation. Water-cooled chiller advantages include greater energy efficiency (at least at design conditions) and longer equipment life.