Carrier 19EF Series Start Up & Operation Manual page 60

Table 9 — LID Primary and Secondary Messages and Custom Alarm/Alert Messages
N. OTHER PROBLEMS/MALFUNCTIONS
DESCRIPTION/MALFUNCTION
Chilled Water/Brine Temperature
Too High (Machine Running)
Chilled Water/Brine Temperature Too Low (Machine
Running)
Chilled Water Temperature Fluctuates. Vanes Hunt
Low Oil Sump Temperature While Running
(Less than 100 F [38 C])
At Power Up, Default Screen Does Not Appear, ''Tables Load-
ing'' Message Continually Appears
SMM Communications Failure
High Oil Temperature While Running
Blank LID Screen
''Communications Failure'' Highlighted Message At
Bottom of LID Screen
Control Test Disabled
Vanes Will Not Open In Control Test
Oil Pump Does Not Run
with Troubleshooting Guides (cont)
Chilled water set point set too high. Access set point on LID and verify.
Capacity override or excessive cooling load (machine at design capacity).
Check LID status messages. Check for outside air infiltration into condi-
tioned space.
Condenser temperature too high. Check for proper flow, examine cooling
tower operation, check for air or water leaks, check for fouled tubes.
Refrigerant level low. Check for leaks, add refrigerant, and trim charge.
Liquid bypass in waterbox. Examine division plates and gaskets for leaks.
Guide vanes fail to open. Use Control Test to check operation.
Chilled water control point too high. Access control algorithm status and check
chilled water control operation.
Guide vanes fail to open fully. Be sure that the guide vane target is released.
Check guide vane linkage. Check limit switch in actuator. Check that sensor
is in the proper terminals.
Chilled water set point set too low. Access set point on LID and verify.
Chilled water control point too low. Access control algorithm status and check
chilled water control for proper resets.
High discharge temperature keeps guide vanes open.
Guide vanes fail to close. Be sure that guide vane target is released. Check
chilled water sensor accuracy. Check guide vane linkage. Check actuator
operation.
Deadband too narrow. Configure LID for a larger deadband.
Proportional bands too narrow. Either INC or DEC proportional bands should
be increased.
Loose guide vane drive. Adjust chain drive.
Defective vane actuator. Check through Control Test.
Defective temperature sensor. Check sensor accuracy.
Check for proper oil level (not enough oil). Check for proper refrigerant level
(too much refrigerant). See protective limit low oil temperature.
Check for proper communications wiring on PSIO module. Check that the
COMM1 communications wires from the LID are terminated to the COMM1
PSIO connection.
Check that PSIO communication plugs are connected correctly. Check SMM
communication plug. Check for proper SMM power supply. See Control Mod-
ules section on page 63.
Check for proper oil level (too much oil). Check that TXV valve is operating
properly.
Adjust contrast potentiometer. Check red LED on LID for proper operation,
(power supply). If LED is blinking, but green LED's are not, replace LID mod-
ule, (memory failure)
LID is not properly addressed to the PSIO. Make sure that ''Attach to Net-
work Device,'' ''Local Device'' is set to read the PSIO address. Check LED's
on PSIO. Is red LED operating properly? Are green LED's blinking? See
control module troubleshooting section.
Press the ''Stop'' pushbutton. The PIC must be in the OFF mode for the
controls test to operate. Clear all alarms. Check line voltage percent on Sta-
tus01 screen. The percent must be within 90% to 110%. Check voltage in-
put to SMM, calibrate starter voltage potentiometer for accuracy. Make sure
starter communication is established.
Low pressure alarm is active. Put machine into pumpdown mode or equal-
ize pressure. Check guide vane actuator wiring. Make sure starter commu-
nication is established.
Check oil pump voltage supply. Cooler vessel pressure under vacuum.
Pressurize vessel. Check temperature overload cutout switch.
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PROBABLE CAUSE/REMEDY