24
ICC Diagnostic Codes
Descriptions of the ICC diagnostic codes are provided below:
11.6
COMFORT CONTROL
2
SYSTEM™
CONTROL WIRING
AND
CONVENTIONAL THERMOSTAT WIRING
ICC DIAGNOSTIC CODES
Dual 7-Segment
LEDs Display
Code
Diagnostic Description
0 – Standby
No command for unit operation
Normal operation
c - First Stage Cooling
Unit has received a command for first stage
cooling
Normal operation
c - Anti-short cycle timer (3 minutes) or
Minimum run timer (30 seconds) active
• The unit has received a command for first stage
cooling during an active anti-short cycle timer
or minimum run timer.
• Wait until unit timer has expired or press the
TEST button to defeat short cycle delay.
C - Second Stage Cooling
Unit has received a command for second
stage cooling
Normal operation
C - Anti-short cycle timer (3 minutes) or
Minimum run timer (30 seconds) active
• The unit has received a command for second
stage cooling during an active anti-short cycle
timer or minimum run timer.
• Wait unit timer has expired or press the TEST
button to defeat short cycle delay.
Status/Possible Cause – Troubleshooting
Information
FLASHING
c
FLASHING
C
t - Test Mode
The ICC is in TEST mode
P – Protector Trip
A command for compressor operation is
present but no current is measured to the
compressor
• Motor protector open
• Line voltage disconnected
01 – Long Run Time (Compressor)
The compressor has continuously run for
more than 18 hours in the cooling mode.
• Low refrigerant charge
• Air ducts have substantial leakage
• Dirty indoor air filter
• Dirty outdoor coil
02 – High Side Fault
Compressor limit has opened four (4) times
within a call for operation
• Outdoor coil is dirty (cooling mode)
• Outdoor fan is not running (cooling mode)
• Dirty indoor coil or filter (heating mode)
• Indoor blower is not running (heating mode)
• Liquid line restriction
• Excessive refrigerant charge
03 – Short Cycling
The ICC detects the run time for the past
four (4) compressor cycles is less than three
(3) minutes each.
• Check thermostat wire connections (R, C, 1, &
2)
• Check thermostat location in zone (too close to
discharge grill)
L4 – Locked Rotor
The ICC detects four (4) consecutive
protector trips have occurred and the
average run time for each trip is less than 15
seconds
• Bad run capacitor
• Low line voltage
• Excessive refrigerant in compressor
• Seized bearings in compressor
