Carrier 48TC 17 Series - Control Board I;O and Troubleshooting

15
Table 1 – Humidi−MiZerR Reheat Control Board I/O
Point Name Type
Connection
Pin Number
Unit
Connection
Note
Humidistat/LTLO DI, 24VAC J1A - 1 (1) LTLO
Thermostat W1 DI, 24VAC J1A - 2 (2) CTB - REHEAT - 4
Econ Y1 DI, 24VAC J1A - 6 (6) CTB - REHEAT - 5
Thermostat G DI, 24VAC J1B - 1 (7) CTB - REHEAT - 1
24V Power (J1) 24VAC J1B - 3 (9) CTB - R
24V Power (J2) 24 VAC J2 - 1 CTB - R
Econ Y2 DI, 24VAC J1B - 5 (11) CTB - REHEAT - 7 2 - circ only
COMP1 DO, 24VAC J1A - 5 (5) CTB - HEAT - 6
IFM DO, 24VAC J1B - 4 (8) CTB - REHEAT - 2
COMP2 DO, 24VAC J1B - 4 (10) CTB - REHEAT - 8
LSV DO, 24VAC J2 - 2 FTP (BLK)
DSV1 DO, 24VAC J2 - 3 DSV
NOT LSV DO, 24VAC J2 - 4 2 - circ only
DSV2 DO, 24VAC J2 - 5 2 - circ only
LEGEND
COMP — Compressor
CTB — Control Terminal Board
DI — Discrete Input (switch)
DO — Discrete Output (switch)
DSV — Discharge (gas) Solenoid Valve
ECON — Economizer
FPT — Freeze Protection Thermostat
IFM — Indoor (supply) Fan Motor
LSV — Liquid Solenoid Valve
LTLO — Low Temperature Lockout
REHEAT — Connection Strip REHEAT (on CTB)
Table 2 – Inputs/Modes/Outputs Summary
Y1 Y2 W1 G
HUM
/ LT
LO
MODE
COMP
1
COMP
2
IFM
LSV
1
LSV2
LSV
NOT
DSV1 DSV2
OFF OFF OFF ON OFF Normal Fan OFF OFF ON=G OFF OFF ON=R OFF OFF
ON OFF OFF On OFF Normal Cool1 ON=Y
1
OFF ON=G OFF OFF ON=R OFF OFF
ON ON OFF ON OFF Normal Cool2 0N=Y2 ON ON=G OFF OFF ON=R OFF OFF
OFF OFF ON X OFF Normal Heat 1 OFF OFF ON=G OFF OFF ON=R OFF OFF
OFF OFF OFF ON ON Reheat Dehumidify ON ON ON=G ON ON OFF ON=R ON=R
ON OFF OFF ON ON Subcool
Cir1/ Reheat
Cir2
Cool1 and Cool2 /
Subcool-Dehumidify
ON ON ON=G ON ON OFF OFF ON=R
ON ON OFF ON ON Subcool
Cir1 and
Cir2
Cool1 and Cool2 /
Subcool-Dehumidify
ON ON ON=G ON ON OFF OFF OFF
OFF OFF ON X ON Heat Over-
ride
Heat 1 OFF OFF ON=G OFF OFF ON=R OFF OFF
OFF OFF ON
+
W2
X ON Heat Over-
ride
Heat 1 and 2 OFF OFF ON=G OFF OFF ON=R OFF OFF