period two

Chilled-Water System Design

notes

Load-Terminal Control Options

Three-way modulating valve

Two-way modulating valve

Face-and-bypass dampers

Figure 33

Load-Terminal Control

The purpose of load-terminal control is to modulate the flow of air or water through the coil to maintain building space comfort. This is accomplished by measuring the temperature of the supply air or space. The temperature then converted to an electronic signal that modulates the capacity of the cooling coil to match the changing load in the space.

Three methods of load-terminal control are commonly used in chilled-water systems.

nThree-way modulating valve control

nTwo-way modulating valve control

nFace-and-bypass damper control

Each of these methods has a different effect on the operation of the system.

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TRG-TRC016-EN

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Trane TRG-TRC016-EN manual Load-Terminal Control Options