An alternative to air-cooled systems and rooftop units, water cooled chiller systems are typically used for industrial and commercial applications for their significant energy savings benefits, and to aid companies in their attempts in reducing carbon emissions.
How Do They Differ From Air-Cooled Systems?
Though water and air cooled systems share many components in common – evaporator, condenser, compressor, expansion valve – unlike air-cooled systems, which disperse heat via an air-cooled condenser coil, water cooled chiller systems use water to absorb heat, dispersing it into the air through a cooling tower. It is this component that gives water cooled systems an efficiency advantage over air-cooled and rooftop systems, from 10-100% depending on the setup.
Why Are They So Much More Efficient?
Water is more energy dense than air, providing more efficient cooling than traditional air-cooled options. However these systems come with one main drawback: A higher equipment cost. They are typically used in locations larger than 200,000 square feet, where cooling needs will quickly offset the added cost of equipment. Other applications include industrial use, such as the cooling of plastics and metals, and the cooling of small and large multi-storied structures like universities, hospitals, and large office buildings, as the systems don’t require ducts to push air through multiple stories. With system sizes ranging from 20 tons to several thousand, applications are wide and varied.
Choosing a Water cooled System
Operation and function of water cooled systems will vary based on your choice of system type. Chillers are typically chosen by application and cooling capacity required in relation to the trade-off between initial investment and operating costs. Make sure to consult with a Commercial HVAC Mechanical Contractor before deciding on the System. Styles include:
The most efficient of water cooled system choices, this system type includes magnetic-bearing compressors, which generate less noise and vibration than other styles and offer significantly improved part-load efficiencies in certain applications compared to screw and scroll style compressors. Centrifugal compressors are typically used in applications requiring 300 tons or more of cooling capacity, though some newer models offer variable-frequency operation.
Dominating the upper end of the capacity range, screw-style compressors are typically used for applications requiring less than 300 tons of cooling capacity.
Scroll compressor are common in applications requiring less than 300 tons of cooling capacity.
A Difficult Decision
Due to the complexities of each application, in-depth analysis is essential to maximize efficiency opportunities with water cooled chiller systems. Various equipment options, load factors, and operating strategies must be considered by professionals in-the-know to ensure a solid investment and lasting performance, such as chiller efficiency, the efficiency of pumps and fans, full/partial load operation, variable frequency versus constant speed compressors, interaction between components, and operating techniques.
Considering an upgrade or experiencing issues with your existing water cooled system? The professionals at H&H Commercial have skills beyond the typical residential or business installation. Contact us to learn more about our trusted commercial services today.