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Service Manual -
HRG18xxS1P
508206-01
Issue 2140
Page 22 of 83
RAST 6-PIN
CONNECTOR
RAST 6-PIN
CONNECTOR
VARIABLE CAPACITY
OUTDOOR UNIT
TWO STAGE /
VARIABLE SPEED
GAS FURNACE
CONVENTIONAL 24VAC
NON-COMMUNICATING
THERMOSTAT
W
L
Y2
Y1
O
DS
C
I+
I-
R
DF
TST
Y1
O
C
W1
R
G
TC
TO
ACC2
ACC1
Y1
O
DH
C
W2
W1
R
G
DS
W2
O.D. SENSOR
OPTIONAL
FOR SINGLE STAGE OPERATION INSTALL A JUMPER BETWEEN Y1 TO Y2 ON THE OUTDOOR UNIT
TERMINAL STRIP
FOR SINGLE STAGE OPERATION INSTALL A JUMPER BETWEEN Y1 TO Y2 ON THE OUTDOOR UNIT
TERMINAL STRIP
RAST 6-PIN
CONNECTOR
RAST 6-PIN
CONNECTOR
VARIABLE CAPACITY
OUTDOOR UNIT
SINGLE STAGE FURNACE /
PSC AIR HANDLER
CONVENTIONAL 24VAC
NON-COMMUNICATING
THERMOSTAT
W
L
Y2
Y1
O
DS
C
I+
I-
R
DF
TST
Y
O
C
W
R
G
TC
TO
ACC2
ACC1
Y1
O
DH
C
W2
W1
R
G
O.D. SENSOR
OPTIONAL
CONSTANT TORQUE /
VARIABLE SPEED
AIR HANDLER
RAST 6-PIN
CONNECTOR
RAST 6-PIN
CONNECTOR
VARIABLE CAPACITY
OUTDOOR UNIT
CONVENTIONAL 24VAC
NON-COMMUNICATING
THERMOSTAT
W
L
Y2
Y1
O
DS
C
I+
I-
R
DF
TST
Y1
O
C
W1
R
G
TC
TO
ACC2
ACC1
Y1
O
DH
C
W2
W1
R
G
DS
W2
O.D. SENSOR
OPTIONAL
FOR SINGLE STAGE OPERATION INSTALL A JUMPER BETWEEN Y1 TO Y2 ON THE OUTDOOR UNIT
TERMINAL STRIP
Figure 12. Conventional 24VAC Cooling Non-
Communicating Thermostat Wiring - Single Stage
RAST 6-PIN
CONNECTOR
RAST 6-PIN
CONNECTOR
VARIABLE CAPACITY
OUTDOOR UNIT
TWO STAGE /
VARIABLE SPEED
GAS FURNACE
CONVENTIONAL 24VAC
NON-COMMUNICATING
THERMOSTAT
W
L
Y2
Y1
O
DS
C
I+
I-
R
DF
TST
Y1
O
C
W1
R
G
TC
TO
ACC2
ACC1
R2
Y2
Y1
O
DH
C
W2
W1
R
G
DS
W2
Y2
O.D. SENSOR
OPTIONAL
RAST 6-PIN
CONNECTOR
RAST 6-PIN
CONNECTOR
VARIABLE CAPACITY
OUTDOOR UNIT
SINGLE STAGE FURNACE /
PSC AIR HANDLER
CONVENTIONAL 24VAC
NON-COMMUNICATING
THERMOSTAT
W
L
Y2
Y1
O
DS
C
I+
I-
R
DF
TST
C
W
R
G
TC
TO
ACC2
ACC1
R2
Y2
Y1
O
DH
C
W2
W1
R
G
Y
O.D. SENSOR
OPTIONAL
CONSTANT TORQUE /
VARIABLE SPEED
AIR HANDLER
RAST 6-PIN
CONNECTOR
RAST 6-PIN
CONNECTOR
VARIABLE CAPACITY
OUTDOOR UNIT
CONVENTIONAL 24VAC
NON-COMMUNICATING
THERMOSTAT
W
L
Y2
Y1
O
DS
C
I+
I-
R
DF
TST
Y1
O
C
W1
R
G
TC
TO
ACC2
ACC1
R2
Y2
Y1
O
DH
C
W2
W1
R
G
DS
W2
Y2
O.D. SENSOR
OPTIONAL
Figure 13. Conventional 24VAC Cooling Non-
Communicating Thermostat Wiring - Two Stage