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Primary Pumping - Application Description

Traditional solution | New standard | Energy Savings
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Application Description
Primary/secondary chilled water systems are generally used in commercial buildings to improve efficiency in large air cooling systems. The primary/secondary pumping system separates the primary production loop from the secondary distribution loop. This allows the chillers and the primary production loop pumps to maintain constant design flow while the secondary system pumps vary the flow based on cooling load demand. 

In chilled water systems, the primary loop consists of non-regulated pumps sized to produce the design flow rate of the chillers at a discharge pressure sufficient to circulate the water through the chillers and the primary loop. The primary loop is as small as possible while able to support the secondary system. This minimizes the resistance in the primary loop, and, therefore, the energy consumption of the constant-flow primary pumps.  More...