York YK-EP Operation And Maintenance Manual page 58

Table 43: Display only
Field/LED name
Surge Avoidance Surge
Count
Surge Avoidance Surge
Detected (LED)
Hot Gas Bypass Control
Mode
Table 44: Valve position
Actual position
0% to 19%
20% to 39%
40% to 59%
60% to 79%
greater than 79%
Table 45: Programmable
Button Access level
Close
Service
Percentage
Hold Period Service
Minimum
Service
Load
Maximum
Open
58
Description
This is the total number of surges accumulated by the Surge
Protection feature. If equipped with a VSD or MVVSD, it is only the
surges detected while the drive is running at maximum frequency.
Illuminates momentarily when a surge is detected by the Surge
Protection feature. If equipped with a VSD or MVVSD these are
only the surges detected while the drive is running at maximum
frequency.
It illuminates momentarily when a surge is detected by the Surge
Protection feature. If equipped with a VSD, it illuminates whenever a
surge is detected, regardless of the VSD operating speed.
Indicates whether the Hot Gas Bypass is under automatic, manual
or override control. When in manual control, it is controlled from
this screen. When in override control, Minimum Load, VSD Override
or VGD Override is displayed as appropriate. Refer to the OptiView
Control Center Service Manual for details of these messages.
Valve position %
0% (fully closed)
25% open
50% open
75% open
100% (fully open)
Description
(5 to 15% Default 15%)
This is the incremental amount that the Hot Gas Valve will be closed
at 10 minute intervals after the HOLD period has elapsed.
(30 to 120 minutes; default 30 minutes)
This is the period of time after no more surges are detected that the
Hot Gas Valve closing will begin.
(0 to 4°F; default 0°F)
This sets the offset below the Leaving Chilled Liquid Temperature
Setpoint at which the Hot Gas Valve will be opened to the position
allowed by the Maximum Open Setpoint.
(25 to 100%)
–
The maximum allowable position for the Hot Gas Valve during a
Minimum load override condition.
YK-EP Style B Centrifugal Chiller