Sterling GP Series User Manual

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GP Series Portable Chillers 
Chapter 4: Operation 
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Chapter 4:   Operation 
4-1  Panel Buttons, Indicator Lights, and Switches 
Microprocessor Controller 
The standard chillers use a microprocessor-based PID controller. The Carel PCO controller 
along with the Carel PGD1 Interface is a modular, self-contained unit that can slide from its 
mounting housing. It is factory set and adjusted; no field adjustment to the internal controls is 
necessary. The standard operation range is 20ºF to 80ºF (-7ºC to 27ºC). 
 
Figure 3 - Controller Display 
Button 
Button Description 
Detailed description 
 
Menu Button 
Used to access the menus structure of the PGD interface 
 
On/Off Button 
Used to turn the entire chiller On or Off.  The button is backlit and will 
turn amber when the chiller is On. 
 
Back Button 
Used to back up from a menu and return to the main status screen 
 
Up Arrow Button 
Used to increment a data field or scroll up within a menu structure. 
 
Enter Button 
Used to accept a data field value or to select a menu item. 
 
Down Arrow Button 
Used to decrement a data field or scroll down within a menu structure.