Carrier 48/50PM C16-28, 48/50PG C03-14 manual Integrated Gas Control IGC Board, IGC Connections

Integrated Gas Control (IGC) Board

The IGC is provided on gas heat units. (See Fig. 42 and Table 25.) The IGC controls the direct spark ignition system and monitors the rollout switch, limit switch, and induced-draft motor Hall Effect switch.

RED LED-STATUS

The IGC is equipped with an LED (light-emitting diode) for diagnostics. See the Troubleshooting section for more information.

48/50PG and PM

C07028

Fig. 42 − Integrated Gas Control (IGC) Board

Table 25 – IGC Connections

TERMINAL	POINT DESCRIPTION	SENSOR LOCATION	TYPE OF I/O	CONNECTION
LABEL				PIN NUMBER
		INPUTS
RT, C	Input power from TRAN 1	control box	24 VAC
SS	Speed sensor	gas section	analog input	J1, 1-3
FS, T1	Flame sensor	gas section	switch input
W	Heat stage 1	MBB	24 VAC	J2, 2
RS	Rollout switch	gas section	switch input	J2, 5-6
LS	Limit switch	gas section	switch input	J2, 7-8
CS	Centrifugal switch (not used)		switch input	J2, 9-10
		OUTPUTS
L1, CM	Induced draft combustion motor	gas section	line VAC
IFO	Indoor fan request	control box	relay	J2, 1
GV (W1)	Gas valve (heat stage 1)	gas section	relay	J2, 12
GV (W2)	Gas Valve (heat stage 2, from MBB)	gas section	Not on IGC

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