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INSTALLATION
Control Box —
Make the control box wiring connec-
tions as follows:
024-030 UNITS — Locate the 6-wire harness that enters the
upper left hand side of the unit control box. See Fig. 2. Lo-
cate the one red wire and one black wire in the harness. Each
of these wires will have a
1
⁄
4
-in. quick-connect terminal at-
tached to the free end. Connect the red wire to TB2 (termi-
nal block), terminal 4. Connect the black wire to TB2, ter-
minal 3.
NOTE: For your reference, there will already be a violet wire
attached to TB2, terminal 4, and an orange wire attached to
TB2, terminal 3.
034,044 UNITS — Locate the red and black wires provided.
See Fig. 1. Each wire has a
1
⁄
4
-in. female quick-connect ter-
minal on one end. Connect the red wire to TB3 (terminal
block), terminal 10. Connect the black wire to TB3, terminal
9. See Fig. 3.
NOTE: For your reference, there will already be a violet wire
attached to TB3, terminal 10, and an orange wire attached to
TB3, terminal 9.
054-074 UNITS — Locate the red and black wires pro-
vided. See Fig. 1. Each wire has a
1
⁄
4
-in. female quick-
connect terminal on one end. Connect the red wire to TB2
(terminal block), terminal 4. Connect the black wire to TB2,
terminal 3. See Fig. 4.
NOTE: For your reference, there will already be a violet wire
attached to TB2, terminal 4, and an orange wire attached to
TB2, terminal 3.
ALL UNITS — Locate the PSIO1 plug assembly in the
accessory kit (see Fig. 1). This will replace plug J7-TOP
(pins 1-18) currently in the PSIO1 module. Then:
1. Locate and carefully disconnect the existing J7-TOP plug
from the module. The supply-air thermistor (SAT) and
return-air thermistor (RAT) must be removed from the
J7-TOP and attached to the new plug assembly.
NOTE: The number 1 should be marked on the jacket of the
SAT, and the number 2 should be marked on the jacket of
the RAT for your reference.
2. Connect the red and black leads from the SAT to termi-
nals 2 and 3 of the new plug, respectively.
3. Connect the red and black leads from the RAT to termi-
nals 5 and 6 of the new plug, respectively.
4. Leave the 2 remaining thermistors and wires connected
to the old plug and push it aside (it is no longer used).
Carefully connect the new plug to the PSIO1 module.
LEGEND
C
— Contactor
CB
— Circuit Breaker
CR
— Control Relay
DSIO
— High-Voltage Relay Module
DU
— Dummy Terminal
HIR
— Heat Interlock Relay
HR
— Heater Relay
IFC
— Indoor (Evaporator) Fan Contactor
IFM
— Indoor (Evaporator) Fan Motor
OFM
— Outdoor (Condenser) Fan Motor
PE
— Power Exhaust
PEC
— Power Exhaust Contactor
PSIO
— Processor Module
QC
— Quick Connect
TB
— Terminal Block
TDR
— Time-Delay Relay
TRAN — Transformer
Fig. 2 — Control Box, 024-030
2