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74
Table 58 — Alarm Codes (cont)
LEGEND
*Code is only available on sizes 034-078.
NOTE: Alarms 89-92 are level zero on the CCN Network. All other alarms are level 2.
DISPLAY
DESCRIPTION
ACTION TAKEN BY
CONTROL
RESET
METHOD
PROBABLE CAUSE
77
High Pressure, Circuit B
Circuit B compressor(s) shut down
Manual
An overcharged system, high outdoor ambient tempera-
ture coupled with a dirty outdoor coil, plugged filter drier,
partially closed liquid line service valve, or a faulty trans-
ducer. This alarm is only valid when the unit has refriger-
ant pressure transducers.
78
Supply-Air Fan State and
Status
All unit outputs (except supply fan)
turned off. Supply fan output
remains energized.
Automatic
Fan status switch failure, tubing not properly connected,
or fan status switch set incorrectly.
79
Not used
—
—
—
80
Low Saturated Suction
Temperature, Circuit A
Circuit A shut down
Manual
Low entering outdoor-air temperature, low evaporator-
fan cfm, low refrigerant charge, plugged filter drier,
partially closed liquid line service valve, or pressure
transducer failure.
81
Low Saturated Suction
Temperature, Circuit B
Circuit B shut down
Manual
Low entering outdoor-air temperature, low evaporator-
fan cfm, low refrigerant charge, plugged filter drier, par-
tially closed liquid line service valve, or pressure trans-
ducer failure
82
High Suction Superheat,
Circuit A
Circuit A shut down
Manual
Low refrigerant charge, plugged filter drier, partially
closed liquid line service valve, or a faulty thermistor or
transducer.
83
High Suction Superheat,
Circuit B
Circuit B shut down
Manual
Low refrigerant charge, plugged filter drier, partially
closed liquid line service valve, or a faulty thermistor or
transducer.
84
Low Suction Superheat,
Circuit A
Circuit A shut down
Manual
Faulty TXV, thermistor, or transducer.
85
Low Suction Superheat,
Circuit B
Circuit B shut down
Manual
Faulty TXV, thermistor, or transducer.
86*
Illegal Configuration
Unit will not start
Manual
Configuration code error.
87
Not used
—
—
—
88
Hydronic Coil Freeze Stat
Economizer at minimum position,
heating coil valve fully open,
supply-air fan shut off
Automatic
Low temperature outdoor-air used with minimum airflow.
Unit is in IAQ purge mode with low temperature
outdoor air. Outdoor-air damper is jammed open.
89
Pressurization
Initializes pressurization mode.
See Table 24 for hardware state
details.
Automatic
Pressurization alarm tripped. Space being overpressur-
ized to prevent smoke from entering zones.
90
Evacuation
Initializes evacuation mode. See
Table 24 for hardware state details.
Automatic
Smoke alarm tripped. Power exhaust fans clear smoke
from space.
91
Smoke Purge
Initializes smoke purge mode. See
Table 24 for hardware state details.
Automatic
Purge alarm tripped. Outdoor air is being supplied and
return air is being exhausted.
92
Fire Shutdown
Unit shuts down. See Table 24 for
hardware state details.
Automatic
Fire alarm tripped.
93
Linkage Failure
Unit returns to stand-alone
operation.
Automatic
Loose connection, a broken wire, or a loss of communi-
cation with the TSM.
94
Building Pressure
Alarm generated.
Automatic
Power exhaust fan failure in either the 1/4-in. plastic
tubing routed to the area to be controlled or the tubing
routed to the atmosphere from the building pressure
control. This alarm is only valid when the unit is config-
ured for modulating power exhaust or return-air fan.
95
Duct Static Pressure
The supply-air fan shuts off for
5 minutes.
Automatic
Inlet guide vane actuator motor failure; or VFD failure; A
leak or obstruction in the 1.4-in. plastic tubing routed
from the inlet guide vane or VFD duct pressure trans-
ducer to the ductwork connection; All the terminals are
closed.
96
Not used
—
—
—
97
Indoor-Air Quality Failure
Alarm generated
Automatic
IAQ set point is less than the IAQ low reference gener-
ated, or the IAQ priority is configured as low and the IAQ
sensor reading exceeds the IAQ set point.
CCN
— Carrier Comfort Network
CV
— Constant Volume
DSIO
— High-Voltage Relay Module
IAQ
— Indoor-Air Quality
NTFC — Nighttime Free Cool
PSIO
— Processor Module
TSM
— Terminal System Manager
TXV
— Thermostatic Expansion Valve
VFD
— Variable Frequency Drive