Specifications

83
configured to use the sensor through the Outside Air RH
Sensor (RRHS) setting, which is located in the
CONFIGURATION-OPTS submenu.
Alert Code 82 (Space Temperature Offset Failure)
— If the
unit is configured to use a space temperature sensor and is
using a T56 sensor with an offset potentiometer, then the alert
will occur if the potentiometer is outside the allowable range.
The control will default to the software applicable set point.
The alert will automatically clear. The unit must be configured
for one of the SPT control options through the Unit
Control Type (CTL.T) configuration, which is located in the
CONFIGURATION-UNIT submenu.
Alarm Code 83 (Evaporator Discharge Sensor Failure)
—
This alarm occurs when the Evaporator Discharge temperature
sensor (EDT) is outside the range –40 to 240 F (–40 to 116 C).
The EDT sensor is located on the side of the supply air fan.
This alarm resets automatically. The cause of the alarm is usu-
ally a faulty thermistor, a shorted or open thermistor caused by
a wiring error, or a loose connection. Because the sensor
controls many of the functions in the unit, all cooling will be
stopped until the failure is corrected.
Alert Codes 92, 93, (Suction Pres. Trans. Failure)
—Alert
codes 92, and 93 are for circuits A and B respectively. These
alerts occur when the pressure is outside the range 0.5 to
134.5 psig. A circuit cannot run when this alert is active. Use
the Scrolling Marquee to reset the alert. The cause of the alert
is usually a faulty transducer, faulty 5-V power supply, or a
loose connection.
Alert Codes 110, 111 (Loss of Charge)
—Alertcodes110,
and 111 are for circuits A, and B respectively. These alerts occur
when the compressor is OFF and the suction pressure < 5 psig
and OAT > –5 F for 1 continuous minute. Use the Scrolling
Marquee to reset the alert. The cause of the alert is usually low
refrigerant pressure or a faulty suction pressure transducer.
These alerts only occur when the compressor is OFF because
the low refrigerant pressure alarms (alerts 133, and 134) handle
this situation when the compressors are operating.
Alert and Alarm Code 120, 121 (Low Saturated Suction Tem-
perature) — Alert codes 120 and 121 are used to protect the
coil from freeze-up during operation. Alert 120 is for circuit A
and 121 for circuit B. If the saturated suction temperature is
less than 28 F for 15 minutes, less than 20 F for 5 minutes, or
less than 5 F for 20 continuous seconds then the alert will occur
for the appropriate circuit. The circuit will be allowed to restart
in 15 minutes. If more than three alerts occur then the circuit
will be locked out and an alarm is generated. If the saturated
suction is greater than 34 F for more than one hour then the
counter will be reset.
Alert Code 122 and 123 (High Saturated Suction Tempera-
ture) — Alert codes 122 and 123 occur when compressors in a
circuit have been running for at least 5 minutes and the circuit
saturated suction is greater than 60 F. The high saturated suc-
tion alert is generated and the circuit is shut down. This condi-
tion resets after OAT drops by 5 F. Alert code 122 is for circuit
A and 123 for circuit B.
Alert Codes 126, 127 (High Refrigerant Pressure)
—Alert
codes 126, and 127 are for circuits A and B respectively. These
alerts occur when alerts 51, 52, 55, or 56 are active and the
appropriate condensing temperature is greater than 150 F.
These alerts reset automatically. The cause of the alarm is
usually an overcharged system, high outdoor ambient tempera-
ture coupled with dirty outdoor coil, plugged filter drier, or a
faulty high pressure switch. See Alerts 51, 52, 55 and 56 for
diagnostic procedure.
Alarm Code 140 (Reverse Rotation Detected)
—Whena
compressor starts in either circuit, the control monitors the
discharge and suction pressure. If a rise in differential is not
detected, then the circuit will be stopped and the circuit locked
off. This will require a manual reset through the Scrolling
Marquee display.
Alarm Code 150 (Unit in Emergency Stop)
— If the fire
safety input condition occurs to indicate a fire or smoke condi-
tion, then Alarm code 150 will occur and the unit will be
immediately stopped. Through separate inputs the unit can be
put into purge, evacuation, and pressurization. This requires a
manual reset.
Alarm Code 151 — Illegal Configuration
— If an illegal
configuration has been set, then alarm code 151 will occur and
the unit will not be allowed to run. Check the unit configura-
tions and make the appropriate corrections.
Alarm Code 152 Unit Down Due to Failure
—Ifthereisa
general fault condition with one of the boards or software, then
the general alarm code 152 will be displayed. Reset the power
and check the operation of the boards using the indicator lights
on the boards. This is a manual reset alarm.
Alert Code 153 — Real Time Clock Hardware Failure
—
A problem has been detected with the real timeclock on the
MBB. Try resetting the power and check the indicator lights. If
the alert continues, the board should be replaced.
Alarm Code 154 — Serial EEPROM Hardware Failure
—
A problem has been detected with the EEPROM on the MBB.
Try resetting the power and check the indicator lights. If the
alarm continues, the board should be replaced.
Alert Code 155 — Serial EEPROM Storage Error
—A
problem has been detected with the EEPROM storage on the
MBB. Try resetting the power and check the indicator lights. If
the alert continues, the board should be replaced.
Alarm Code 156 — Critical Serial EEPROM Storage Error
— A problem has been detected with the EEPROM storage on
the MBB. Try resetting the power and check the indicator
lights. If the alarm continues, the board should be replaced.
Alarm Code 157 — A/D Serial EEPROM Storage Failure
Error — A problem has been detected with A/D conversion on
the boards. Try resetting the power and check the indicator
lights. If the alarm continues, the board should be replaced.
Alarm Codes 163, 164, 165 (Circuit Failure)
— Alarm codes
163, 164, and 165 are for circuits A, B, and C, respectively.
These alarms occur when a circuit has 3 strikes. Use the Scroll-
ing Marquee display to reset the alarm. Investigate the alarm
that caused the strikes to occur.
Alarm Code 171 — Loss of Communications with the
Staged Gas Control Board — This alarm indicates that there
are communications problems with the staged gas heat control
board, which is located in the gas section on units equipped
with staged gas heat. If this alarm occurs, the staged gas heat
will be disabled. The alarm will automatically reset.
Alarm Code 172
— Loss of Communications with the Con-
trols Expansion Board — This alarm indicates that there are
communications problems with the Controls Expansion Board.
All functions performed by the CEM will stop, which can in-
clude demand limit, reset, fire control modes, and the fan status
switch. The alarm will automatically reset.
Alarm Code 173
— Loss of Communications with the
ECB1 — This alarm indicates that there are communications
problems with the Economizer Control Board. This will result
in the economizer and the power exhaust not working and the
dampers to be fully closed. The exhaust fans will stop. The
alarm will automatically reset.
Alarm Code 174
— Loss of Communications with the
ECB2 — This alarm indicates that there are communications
problems with the ECB2 which controls the VAV unit indoor
fan inverter speed and hot gas bypass on CV and VAV units.
Because the control of the fan is critical to unit operation, the
unit will be stopped. The alarm will automatically reset.