York YK-EP, Operation And Maintenance Manual

Page: 71 / 268

Economizer Variable Geometry Diffuser setpoints screen
Figure 24: Economizer VGD setpoints screen
This screen displays information for the Economizer VGD Setpoints information. Also, the
Economizer VGD Setpoints can be changed from this screen.
Table 59: Display only
Field/LED name Description
Stall Detector Voltage
Displays the Stall Detector output voltage as received by the
Microboard.
High Limit
Displays the voltage. If the voltage is exceeded the VGD will close to
prevent the unit from stalling.
Low Limit
Displays the voltage, that if has dropped below the setpoint, will
cause the VGD to open, allowing more gas through the compressor.
Mach Number
Displays the speed of the refrigerant gas leaving the compressor in
percentage of Mach (the speed of sound).
VGD Closed Limit Switch
Displays the status of the VGD Limit Switch. Displayed as CLOSED
when the switch is closed. This would be when the VGD is in the fully
closed position. Otherwise, displayed as OPEN.
VGD Opening (LED) Illuminates when a close signal is being applied to the VGD.
VGD Closing (LED) Illuminates when an open signal is being applied to the VGD.
71 YK-EP Style B Centrifugal Chiller