York YK-EP, Operation And Maintenance Manual

Page: 255 / 268

This setpoint is set at the factory at time of manufacture and requires an ADMIN password to
change it. It is only visible when set to Extended. The selections are:
1. Standard – Uses standard high pressure warning and safety shutdown thresholds as follows:
- Warning – High Pressure Limit – Maximum allowable value is 162.5 PSIG
- Condenser – High Pressure – Trip/reset threshold is 180/120 PSIG
- Condenser – High Pressure – Stopped – Trip/reset threshold 160 PSIG.
2. Extended – Uses higher high pressure warning and safety shutdown thresholds as follows:
- Warning – High Pressure Limit – Maximum allowable value is 193.0 PSIG
- Condenser – High Pressure – Trip/reset threshold is 200/140 PSIG
- Condenser – High Pressure – Stopped – Trip/reset threshold is 170 PSIG
PRV Position New production chillers can be equipped with an optional Pre-rotation Vanes
potentiometer, regardless of other options. This setpoint allows the software to be used in all YK-
EP chillers, whether equipped with the potentiometer or not. The PRV position will be shown on
respective screens when Enabled; not shown when Disabled.
1. Enabled – Automatically set to this setting if Hot gas bypass or Variable Geometry Diffuser
(VGD) is enabled on the OPERATIONS Screen or Motor Drive Type setpoint is set to VSD or
MVVSD. The actual connection point of the potentiometer is determined by the equipment
configuration:
- If equipped with a VSD in YORK Protocol configuration, it is connected to the ACC
Board.
- In Modbus Protocol configuration, it is connected to the microboard J7.
If not equipped with a VSD, but equipped with Hot gas bypass, the connection
point is determined by which I/O Board is present. With I/O Board 371-02514-000
or 031-02895-000, it is connected to this board; otherwise, it is connected to the
microboard J7. If not equipped with Hot gas bypass but equipped with a VGD, it is
connected to the microboard J7.
2. Disabled – Set to this position when not equipped with a PRV potentiometer. If equipped with
a VSD, MVVSD or the Hot gas bypass or Variable Geometry Diffuser is enabled, this setpoint is
automatically enabled and cannot be set to disabled.
- Motor Monitoring
The Motor Monitoring feature to be enabled or disabled. Motor Monitoring can not be
used with the 371-02514-000 since the Motor Monitoring and the Frick Analog board
use different protocols.
- Heat Recovery
Allows the Heat Recovery feature to be enabled or disabled.
- Head Pressure Control
Allows the Head Pressure feature to be enabled or disabled.
255 YK-EP Style B Centrifugal Chiller