2-40 HP Portable Chillers Chapter 4: Operation 32 of 70
Graphic Panel
(See Figure 8)
Indicator Name Description
Compressor On
Light The Compressor On light turns on whenever the
compressor is operating.
Low Temperature
Light The Low Temperature light comes on if the process
water/glycol temperature drops below the High/Low
thermostat set point. The Low thermostat stage one
switch opens the control circuit shutting down the
compressor, but the process water/glycol pump(s)
continue to operate. This action prevents possible
chiller evaporator freeze-up.
Hot Gas Bypass
Light The Hot Gas By-Pass light turns on when the hot
gas bypass valve is in operation. The OUT1 LED on
the controller also lights when the hot gas bypass
valve is in operation.
High Temperature
Light The High Temperature light comes on if the process
water/glycol temperature rises above the High/Low
thermostat stage two set point. The High thermostat
stage two switch opens the control circuit shutting
down the process water/glycol pump(s), and the
chiller shuts off. This action prevents possible
system failure from overheating of the process
water/glycol.
Pump On Light The Pump On light, installed on chillers with a
pump, lights whenever the pump(s) operates.
High Discharge
Temperature Light The High Discharge Temperature light comes on if
the compressor discharge line temperature switch
opens. This switch prevents possible compressor
failure due to over loading, the compressor stops,
but the pump(s) continue to run. This occurs when
the discharge line temperature rises above 260ºF
(127ºC). Call a qualified refrigeration service
technician or contact the Service Department.
Pump Overload
Light The Pump Overload light, installed on chillers with
a pump(s), lights whenever a pump motor(s) has
shut down from a motor overload condition.
High Refrigerant
Pressure Light The High Refrigerant Pressure light comes on if the
compressor discharge pressure exceeds the limit of
the high pressure cutout switch. The compressor
stops but the pump(s) continue to run until you
manually reset the high-pressure cutout switch. Call
a qualified refrigeration service technician or
contact the Service Department.