York YK-EP Operation And Maintenance Manual page 24

Table 5: Programmable
Button Access level
Clear Fault Service
Warning
Operator
Reset
Start/Stop
Operator
Soft Key
Table 6: Navigation
Button Description
System Used to provide additional system information.
A detailed view of all evaporator parameters, including the programmable
Evaporator
Leaving Chilled Liquid Setpoints.
A detailed view of all condenser parameters, including control of the liquid
Condenser
level functions.
A detailed view of all the compressor parameters. This includes Pre-Rotation
Compressor Vane control, Hot Gas Bypass Control, Proximity Probe Calibration, and PRV
Calibration.
A detailed view of all the oil pump and oil sump parameters. This includes the
Oil Sump Variable Speed Oil Pump when installed. It also controls the Seal Lubrication
functionality.
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Description
When any safety conditions have been detected and the chiller has
been shutdown, the main status display of the chiller will continue
to display a message indicating the cause of the shutdown. Using
this key, the message can be cleared once the Safety condition has
been removed.
Use of this key acknowledges a warning condition and resets the
message display associated with it.
This key will initially be displayed as Start and when pressed, allows
the operator to Start the chiller. If the chiller is in Local mode it
will start immediately. If the chiller is in Remote mode then it will
start once the Start key is pressed and the remote mode calls for
a start. Once started, the soft key changes to Stop and if pressed,
will initiate a Soft Stop. A Soft Stop fully closes the Pre-Rotation
Vanes prior to shutting down the compressor. This reduces bearing
wear by eliminating compressor backspin at shutdown. While the
vanes are closing, "Vanes Closing Before Shutdown" is displayed
on the System Status Line. When the Vane Motor Switch (VMS)
closes, indicating the vanes have fully closed (or 3.5 minutes
have elapsed, whichever occurs first), the Run signal is removed
from the compressor motor starter and a System Coastdown is
performed. While the vanes are closing, if a Safety Stop is initiated
with the Safety Stop Switch or any fault other than Leaving Chilled
Liquid Temp – Low Temperature, Remote Stop, Multi-Unit Cycling –
Contacts Open, System Cycling – Contacts Open Or Control Panel –
Schedule occur, it will immediately enter System Coastdown.
YK-EP Style B Centrifugal Chiller