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Plate Heat Exchanger and Free Cooling - This plate heat exchanger is used in a data center for a chilled water system and is a chilled water economizer. Heat exchangers are used in marine applications, industrial processes including chemical processing systems, food processing, and many HVAC applications including chilled water applications, hot water applications, and economizer applications.
Plate Heat Exchanger and Free Cooling
In chilled water applications, heat exchangers can be used to bypass the chiller when outdoor ambient temperatures are optimal for using the cooling tower for free cooling. Generally, this free cooling mode can only be used with plate heat exchangers when outdoor ambient air temperatures are below 50 degrees Fahrenheit. When heat exchangers are used for free cooling the control system uses valves to isolate the chiller from the rest of the loop and the heat exchanger is used as a chiller.
Plate Heat Exchanger and Free Cooling
The complexity and engineering of controlling the free cooling system are done by direct digital controls. Direct digital controls will open and close the correct valves in the proper sequence along with activating the correct pumps to make sure that the system is as efficient as possible for the best energy efficiency possible. The sequence of operation includes using many sensors, actuators, pumps, and valves (controlled by the actuators), the heat exchanger, a cooling tower, and the proper piping of the system.
Basically, the water is carried outside to the cooling tower where the water is naturally chilled through the cooling tower process, then the water is pumped back into the building and into the plate heat exchanger where on one side of the plate is the chilled water while on the other side is the warm water which is coming from the air handlers and computer room air conditioners.
The chilled water exchanges heat with the warmer water that then returns to the air handler or computer room air conditioner while the other water now holding the heat returns to the cooling tower to be chilled again. This whole process keeps the chillers from running which chillers need a lot of energy to run.
Plate Heat Exchanger and Free Cooling
