Carrier Complete Guide to IGC Control Board LED Alarms and Error Codes

The alarm codes for the IGC control board are shown in Table 44.

Table 44 — IGC Control Board LED Alarms

INDICATION	ERROR MODE
ON	Normal Operation
OFF	Hardware Failure
1 FLASH	Fan ON/OFF Delay Modified
2 FLASHES	Limit Switch Fault
3 FLASHES	Flame Sense Fault
4 FLASHES	4 Consecutive Limit Switch Faults
5 FLASHES	Ignition Lockout Fault
6 FLASHES	Induced Draft Motor Fault
7 FLASHES	Rollout Switch Fault
8 FLASHES	Internal Control Fault
9 FLASHES	Software Lockout

Diagnostic LEDs — There are 3 LEDs (red, yellow, and green) on the lower right hand side of the control board. The red light is used to check unit operation and alarms. A constant pulse is normal unit operation. A series of quick blinks indi- cates an alarm. Refer to Table 45 below for a description of alarms. The yellow LED blinks during transmission with the CCN (Carrier Comfort Network). The green LED blinks dur- ing transmission with the expansion board.

Table 45 — Control Board LED Alarms

LED	ERROR	DESCRIPTION	RESET	ACTION TAKEN	TROUBLESHOOTING COMMENTS
BLINKS	CODE		METHOD	BY CONTROL
1	—	Normal Operation	—	None	The expansion board and control board flash the red LED
					in one-second intervals when the board is operating properly.
2	HF-13	Compressor 1 Safety	Automatic	Cooling disabled.	The high or low pressure safety switch for compressor no. 1
			and	Automatic reset after	has opened for 3 seconds. The error will be cleared and
			Manual	15 minutes. Manual if	compressor no. 1 will be allowed to turn on in 15 minutes.
				repeated 3 times in	If the safeties have been tripped 3 times in 90 minutes,
				90 minutes.	compressor no. 1 will be locked out until the control
					board has been manually reset.
3	HF-14	Compressor 2 Safety	Automatic	Cooling disabled.	The high or low pressure safety switch for compressor no. 2
			and	Automatic reset after	has opened for 3 seconds. The error will be cleared and
			Manual	15 minutes. Manual if	compressor no. 2 will be allowed to turn on in 15 minutes.
				repeated 3 times in	If the safeties have been tripped 3 times in 90 minutes,
				90 minutes.	compressor no. 2 will be locked out until the control
					board has been manually reset.
4	HF-15	Thermostat Failure	Automatic	Alarm generated.	The thermostat is calling for both heating and cooling
					at the same time. The unit will operate on a first call basis
					and will automatically reset.
5	HF-05	SAT Thermistor Failure	Automatic	Heating, cooling, and	The supply-air temperature (SAT) sensor has failed.
				economizer disabled.	First check for wiring errors, then replace sensor.
6	HF-06	OAT Thermistor Failure	Automatic	NTFC, IAQ purge,	The outside air temperature (OAT) sensor has failed.
				economizer, and low	First check for wiring errors, then replace sensor.
				ambient DX cooling
				locked out disabled.
7	HF-03	Space Temp. Sen. Failure	Automatic	Disables unoccupied	The space temperature sensor has failed.
				cooling/heating, CV	First check for wiring errors, then replace sensor.
				economizer, and CV
				cooling/heating.
8	HF-12	RAT Thermistor Failure	Automatic	VAV heating	The return-air temperature (RAT) sensor has failed.
				disabled.	Ensure that the unit is a VAV unit. If NOT a VAV unit set
					DIP switch position 1 to the closed position and reset power.
					Then check for wiring errors. Finally, replace sensor.
9	SE-05	Loss of Communications	Automatic	Algorithms in	Communications between the expansion board and the
		with Expansion Board		expansion board are	control board have been interrupted. Ensure that an
				bypassed.	expansion board is installed and wired using the
					wire harness supplied with the expansion module. If an
					expansion board is not used ensure that DIP switch position
					3 is in the closed position, and reset power.
10	HF-16	Control Board Failure	None	Control uses default	Generated when hardware has failed on control board.
				values. (May seem	Replace the control board.
				as normal operation)
		Analog to Digital	None	All outputs turned off.
		Conversion
11	HF-17	Expansion Board Failure	None	All outputs turned off.	Generated when hardware has failed on the
					expansion board. Replace the expansion board.
12	SE-23	Cooling SAT Low	Automatic	Alarm generated.	CV operation. When SAT low limits are below range and
		Limit Shutdown			compressor shut off.

LEGEND

DIP — Dual In-Line Package

VAV — Variable Air Volume

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