York YK Style H Operation Manual page 186

For special order R-134a high condenser temperature chiller applications, the Condenser
Temperature Range Setpoint is set to Extended. The trip/reset threshold is then 200/140 PSIG.
Condenser – High Pressure – Stopped
The condenser pressure exceeded 160.0PSIG (R-134a), while the chiller was stopped. High
temperature condenser water flowing through the condenser while the chiller is shutdown
can cause a condenser high pressure condition resulting in loss of refrigerant. This safety fault
anticipates this problem by annunciating the condenser high pressure condition. The chiller can be
restarted after a Service Technician performs a special reset preset procedure contained in OptiView
Control Center – Service Instructions (Form 160.76-M1).
For special order R-134a high condenser temperature chiller applications, the Condenser
Temperature Range Setpoint is set to Extended. The trip/reset is then 170/170 PSIG .
Condenser – Pressure Transducer Out Of Range
The Condenser Pressure transducer is indicating a pressure that is:
• Less than 6.8 PSIG (R-134a)
• Or more than 300.0 PSIG R-134a
This is outside the normal operating range of the transducer. This is generally indicates a defective
transducer. The chiller can be started after the transducer is indicating a pressure that is within
range and the Clear Fault key is pressed on the display.
Auxiliary Safety – Contacts Closed
The Auxiliary safety shutdown contacts, connected to I/O Board TB4-31 have closed, initiating a
safety shutdown. This input is a general-purpose, user defined safety shutdown input. The chiller
can be started after the contacts open and the Clear Fault key is pressed on the display.
Discharge – High Temperature
The discharge temperature, as sensed by the Discharge Temperature Transmitter, has increased to
greater than 220.0°F. The chiller can be started after the temperature decreases to less than 220.0°F
and the Clear Fault key is pressed on the display.
Discharge – Low Temperature
The discharge temperature, as sensed by the Discharge Temperature Transmitter, has decreased
to less than 30.0°F. The chiller can be started after the temperature increases to greater than 30.0°F
and the Clear Fault key is pressed on the display.
Oil – High Temperature
The oil temperature, as sensed by the Oil Temperature Transmitter, has increased to greater than
180.0°F. The chiller can be started after the temperature decreases to less than 180.0°F and the
Clear Fault key is pressed on the display.
Oil – Low Differential Pressure
The differential oil pressure decreased to less than 15.0 PSID while the chiller was running or failed
to achieve 25.0 PSID by the last 5 seconds of the System Prelube period. The differential oil pressure
is the difference between the output of the Sump Oil Pressure transducer (system low pressure)
and the output of the Pump Oil Pressure transducer (system high pressure). The chiller can be
started after the Clear Fault key is pressed on the display.
Oil – High Differential Pressure
The differential oil pressure increased to greater than 120.0 PSID while the oil pump was running.
The differential oil pressure is the difference between the output of the Sump Oil Pressure
186 Model YK Style H Centrifugal Liquid Chillers with OptiView Control Center