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36
Table 17 — PIC 5 Alarm Codes (cont)
ALARM
CODE
(ALARMRST)
ALARM TEXT
DESCRIPTION
RESET TYPE
ACTION TAKEN
BY CONTROL
POSSIBLE CAUSE
PRESTART FAILURES (CONT)
Alm-234
ALM-234 Prestart Failure
— Low Line Voltage
Manual
Unit shuts down.
Compressor is
not allowed to
start.
Check ACTUAL LINE VOLTAGE.
Check UNDERVOLTAGE THRESHOLD
in ISM_CONF screen.
Check voltage supply.
Check wiring to ISM J3-L1, J3-L2, and
J3-L3.
Check voltage transformers and switch
gear.
Consult power utility if voltage is low.
Alm-235
ALM-235 Prestart Failure
— High Line Voltage
Manual
Unit shuts down.
Compressor is
not allowed to
start.
Check ACTUAL LINE VOLTAGE.
Check OVERVOLTAGE THRESHOLD
in ISM_CONF screen.
Check voltage supply.
Check voltage transformers and switch
gear.
Consult power utility if voltage is high.
Alm-236
ALM-236 Guide Vane 1 —
Calibration Not Completed
Manual
Unit shuts down.
Compressor is
not allowed to
start.
Perform Guide Vane Calibration in
Quick Test screen.
Check guide vane actuator feedback
potentiometer and wiring to IOB
connector.
Alm-237
ALM-234 Prestart Failure
— No Power Supply
Manual
Unit shuts down.
Compressor is
not allowed to
start.
If WATER VERIFICATION TIME has
passed after REQUEST TO START had
been sent, there is still no PERMISSION
TO START received
Alm-239
ALM-239 Envelop Control
Valve Calibration Not
Completed
Manual
Unit shuts down.
Compressor is
not allowed to
start.
EC valve calibration failed during control
test mode or prestart check.
PROTECTIVE LIMITS
Alm-250
ALM-250 Protective Limit
— Oil Pressure Difference
Failure
Manual
Unit shuts down.
Check oil pump.
Check oil filter.
Check oil pump wiring.
Alm-251
ALM-251 Protective Limit
— Low Chilled Water Flow
Manual
Unit shuts down.
Perform Chilled Water pump test in
Quick Test screen.
Check evaporator refrigerant liquid tem-
perature and leaving chilled water tem-
perature sensor accuracy and wiring to
IOB.
Check chilled water valves, pumps, and
strainers.
Check EVAP REFRIG TRIPPOINT,
EVAP APPROACH ALERT, EVAP
FLOW DELTA P CUTOUT, and WATER
FLOW VERIFY TIME settings.
Check load resistors, optional water flow
switches or water flow delta P trans-
ducer calibration and wiring to IOB.
Check for 5.0 v reference voltage
between IOB connectors.
Alm-252
ALM-252 Protective Limit
— Low Condenser Water
Flow
Manual
Unit shuts down.
Perform Condenser Water pump test in
Quick Test screen.
Check condenser pressure transducer
and leaving condenser water tempera-
ture sensor accuracy and wiring.
Check condenser water valves and
strainers.
Check COND PRESS OVERRIDE,
COND APPROACH ALERT, COND
FLOW DELTA P CUTOUT, and WATER
FLOW VERIFY TIME settings.
Check load resistors, optional water flow
switches or water flow delta P trans-
ducer calibration and wiring to IOB.
Check for 5.0 v reference voltage
between IOB connectors.