→ Fig. 9—Typical 24-v Circuit Connections
A94390
FAN COIL
Y/Y2
W/W1
C
R
24 VAC HOT
24 VAC COM
HEAT STAGE 2
COOL/HEAT
STAGE 1
INDOOR FAN
CORPORATE
NON-PROGRAMMABLE
THERMOSTAT
MODEL HP
HEAT
PUMP
RVS COOLING
NOT USED
NOT USED
TROUBLE
OPTIONAL
OUTDOOR
SENSOR
CONNECTION
S2
S1
B
Y1
R
C
W2
G
G
Y
O/W2
O
W2
R
C
L
FA, FB, FC,
FD, FF
A95215
Y/Y2
W/W1
R
24 VAC HOT
FAN
FURNACE
COMPRESSOR
RVS COOLING
N/A
DUAL FUEL
THERMOSTAT
SINGLE-SPEED
HEAT PUMP
24 VAC COM
RVS HEATING
RVS SENSING
OUTDOOR
SENSOR
CONNECTION
G
R
R
W
Y
Y
G
C
C
O/W2
Y1/W2
SINGLE-STAGE
FURNACE
W2
O
OUTDOOR
TEMPERATURE
SENSOR
SEE NOTE 1
S2
S1
L
B
C
A94391
FAN COIL
Y/Y2
W/W1
G
R
24 VAC HOT
INDOOR FAN
HEAT STAGE 2
COOL/HEAT
STAGE 1
RVS COOLING
NOT USED
CORPORATE
PROGRAMMABLE
THERMOSTAT
MODEL HP
HEAT
PUMP
24 VAC COM
NOT USED
TROUBLE
OPTIONAL
OUTDOOR
SENSOR
CONNECTION
S2
S1
B
C
R
G
W2
O
Y1/W2
Y
O/W2
W2
R
L
C
C
FA, FB, FC,
FD, FF
A95216
Y/Y2
W/W1
R
24 VAC HOT
FAN
FURNACE LO
COMPRESSOR
RVS COOLING
FURNACE HI
DUAL FUEL
THERMOSTAT
SINGLE-SPEED
HEAT PUMP
24 VAC COM
RVS HEATING
RVS SENSING
OUTDOOR
SENSOR
CONNECTION
S2
S1
L
B
G
R
R
Y
G
C
C
C
O/W2
Y1/W2
TWO-STAGE OR
VARIABLE SPEED
FURNACE
W2
O
SEE NOTES 1 AND 2
W/W1
Y/Y2
O
W2
Y1
OUTDOOR
TEMPERATURE
SENSOR
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