Carrier 19XL Other PROBLEMS/MALFUNCTIONS, DESCRIPTION/MALFUNCTION Probable CAUSE/REMEDY

Table 9 Ð LID Primary and Secondary Messages and Custom Alarm/Alert Messages

with Troubleshooting Guides (cont)

N. OTHER PROBLEMS/MALFUNCTIONS

DESCRIPTION/MALFUNCTION	PROBABLE CAUSE/REMEDY
	Chilled water set point set too high. Access set point on LID and verify.
	Capacity override or excessive cooling load (chiller at design capacity).
	Check LID status messages. Check for outside air in®ltration into
	conditioned space.
	Condenser temperature too high. Check for proper ¯ow, examine cooling
	tower operation, check for air or water leaks, check for fouled tubes.
Chilled Water/Brine Temperature	Refrigerant level low. Check for leaks, add refrigerant, and trim charge.
	Liquid bypass in waterbox. Examine division plates and gaskets for
Too High (Machine Running)
	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
Chilled Water/Brine Temperature Too Low	check chilled water control for proper resets.
	High discharge temperature keeps guide vanes open.
(Machine Running)
	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. Con®gure LID for a larger deadband.
	Proportional bands too narrow. Either INC or DEC proportional bands
Chilled Water Temperature Fluctuates.	should be increased.
Vanes Hunt	Loose guide vane drive. Adjust chain drive.
	Defective vane actuator. Check through Control Test.
	Defective temperature sensor. Check sensor accuracy.
Low Oil Sump Temperature While Running	Check for proper oil level (not enough oil). Check for proper refrigerant
(Less than 100 F [38 C])	level (too much refrigerant).
At Power Up, Default Screen Does Not Appear,	Check for proper communications wiring on PSIO module. Check that
	the COMM1 communications wires from the LID are terminated to the
``Tables Loading'' Message Continually Appears
	COMM1 PSIO connection.
SMM Communications Failure	Check that PSIO communication plugs are connected correctly. Check
	SMM communication plug. Check for proper SMM power supply. See
	Control Modules section on page 78.
High Oil Temperature While Running	Check for proper oil level (too much oil). Check that TXV valve is
	operating properly.
Blank LID Screen	Increase contrast potentiometer. See Fig. 40. Check red LED on LID for
	proper operation, (power supply). If LED is blinking, but green LED's are
	not, replace LID module, (memory failure)
``Communications Failure'' Highlighted Message	LID is not properly addressed to the PSIO. Make sure that ``Attach to
	Network Device,'' ``Local Device'' is set to read the PSIO address. Check
At Bottom of LID Screen	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 Disabled	controls test to operate. Clear all alarms. Check line voltage percent on
	Status01 screen. The percent must be within 90% to 110%. Check
	voltage input to SMM, calibrate starter voltage potentiometer for
	accuracy.
Vanes Will Not Open In Control Test	Low pressure alarm is active. Put chiller into pumpdown mode or
	equalize pressure. Check guide vane actuator wiring.
Oil Pump Does Not Run	Check oil pump voltage supply. Cooler vessel pressure under vacuum.
	Pressurize vessel. Check temperature overload cutout switch.
NOTE: See Legend on page 68.

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