A94221
Fig. 8—Two-Speed Air Conditioner with Single-
Stage Furnace
COOL STAGE 1
FAN
HEAT STAGE 1
COOL STAGE 2
N/A
24 VAC HOT
R
W/W1
Y/Y2
O/W2
Y1/W2
G
24 VAC COMM.
N/A
TROUBLE
OUTDOOR
SENSOR
CONNECTION
C
B
L
S1
S2
C
Y2
C
MODEL 2S
THERMOSTAT
SINGLE-STAGE
FURNACE
TWO-SPEED
AIR CONDITIONER
See note 4
W
R
Y1
R
G
L
Y
Fig. 9—Two-Speed Air Conditioner with 2-Stage or
Variable-Speed Furnace
A94222
COOL STAGE 1
FAN
HEAT STAGE 1
COOL STAGE 2
HEAT STAGE 2
24 VAC HOT
R
W/W1
Y/Y2
O/W2
Y1/W2
G
24 VAC COMM.
N/A
TROUBLE
OUTDOOR
SENSOR
CONNECTION
C
B
L
S1
S2
C
Y2
C
MODEL 2S
THERMOSTAT
TWO-STAGE OR
VARIABLE-SPEED
FURNACE
TWO-SPEED
AIR CONDITIONER
See note 5
R
Y1
R
G
L
W/W1
Y/Y2
W2
Fig. 10—Two-Speed Air Conditioner with Typical
Fan Coil
A94223
24 VAC HOT
FAN
HEAT STAGE 1
COOL STAGE 2
HEAT STAGE 2
COOL STAGE 1
R
G
W/W1
Y/Y2
O/W2
Y1/W2
R
G
24 VAC COMM.
N/A
TROUBLE
OUTDOOR
SENSOR
CONNECTION
C
B
L
S1
S2
C
Y2
C
MODEL 2S
THERMOSTAT
TYPICAL
FAN COIL
TWO-SPEED
AIR CONDITIONER
See notes 5 and 7
W2
Y/Y2 *
Y1
E
L *
O *
R
W3
*
Y1
L
A94224
Fig. 11—Two-Speed Heat Pump with Single-Stage
Furnace
COOL/HEAT
STAGE 1
RVS COOLING
HEAT STAGE 3
COOL/HEAT
STAGE 2
FAN
24 VAC HOT
R
W/W1
Y/Y2
O/W2
Y1/W2
G
24 VAC COMM.
RVS HEATING
TROUBLE
OUTDOOR
SENSOR
CONNECTION
C
B
L
S1
S2
C
Y
Y2
C
W2
MODEL 2S
THERMOSTAT
SINGLE-STAGE
FURNACE
TWO-SPEED
HEAT PUMP
See note 4
R
Y1
O
R
W3
G
L
W
5
