28
Dual 7-Segment
LEDs Display
Code
Diagnostic Description
Status/Possible Cause – Troubleshooting
Information
29 – High Pressure Control Open
The ICC detects the HPC is open
• 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
L29 –
Active Protection
High Pressure
Control Trip
LPC has opened 3 times in the same cooling
operation, the ICC has locked out the com-
pressor to protect it. ICC alternately flashes L
and 29
(see 29 above)
LPC has opened 3 times in the same cooling
operation, the ICC has locked out the compressor
to protect it. ICC alternately flashes L and 29
•
FLASHING
L
80 – Low Air Flow
The ICC detects that the indoor unit is
not providing the minimum airflow
requirements.
• Misapplied/wrong indoor air mover –
replace with properly sized unit.
83 – Condenser Coil Temperature Fault
The sensor detects an abnormally low or
high coil temperature
• Replace the sensor
• Check sensor is installed correctly on control
84 – Outdoor Ambient Temperature Fault
The sensor detects an abnormally low or
high outdoor ambient temperature
• Check unit placement – If the outdoor unit is in
a high temperature area, wait until the ambient
temperature drops and check sensor reading.
• Replace the sensor.
• Check sensor is installed correctly on control
93 – Internal Control Fault
The control is not functioning
properly.
• Check control for proper system
operation.
• Replace control
30 – Fuse Open
The ICC detects the on-board fuse is open
• The 3-amp fuse on the ICC is open.
• Low voltage wiring at R and C is damaged or
miswired.
d1 – No Shared Data
• Replace memory card with correct system
information.
d3 – Airflow CFM Mismatch
The indoor air mover (air
handler/furnace) cannot supply the
required airflow for proper system
operation
• Misapplied/wrong indoor air mover –
replace with properly sized air
handler/furnace.
d4 – (Device) Memory Card Invalid for
Device
The data in the memory card inserted
into the control board does not match
the data in the control.
• Check memory card to ensure it matches
device
• Check if memory card is present
d8 – Old Shared Data
System data is obsolete
• If system will not operate, order new
memory card to update system
information.
28 – High Line Voltage Fault
• Check line voltage
2 8
2 9
2 9
3 0
8 0
8 3
8 4
9 3
L
I
3
4
8