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WIRING DIAGRAM NOTES:
1. CARRIER THERMOSTAT WIRING DIAGRAMS ARE ONLY ACCU-
RATE FOR MODEL NUMBERS BEGINNING WITH TSTAT _ _ _ _ _
_ _.
2. WIRING MUST CONFORM TO NEC OR LOCAL CODES.
3. SOME UNITS ARE EQUIPPED WITH PRESSURE SWITCH(ES), TEM-
PERATURE SWITCH, OR 5-MINUTE COMPRESSOR CYCLE PRO-
TECTION.
CONNECT
24-V
FIELD
WIRING
TO
FACTORY-
PROVIDED STRIPPED LEADS.
4. A LIQUID-LINE SOLENOID VALVE IS REQUIRED ON SOME
UNITS.
5. THERMOSTATS ARE FACTORY CONFIGURED WITH 5-MINUTE
COMPRESSOR CYCLE PROTECTION AND 4 CYCLES PER HR
LIMIT. SEE THERMOSTAT INSTALLATION INSTRUCTIONS FOR
DETAILS.
6. TO STAGE ELECTRIC RESISTANCE HEAT, CONSULT OUTDOOR
THERMOSTAT INSTALLATION INSTRUCTIONS.
7. FOR DUAL FUEL THERMOSTATS, UNDERLINED LETTER ON
DUAL TERMINAL INDICATES ITS USAGE.
FOR EXAMPLE: O/W2 MEANS O
O/W2 MEANS W2
OUTDOOR TEMPERATURE SENSOR MUST BE ATTACHED IN ALL
DUAL FUEL INSTALLATIONS.
JUMPER WIRE BETWEEN O/W2 AND L THERMOSTAT TERMI-
NALS MUST BE PRESENT.
8. Y1 AND O CONNECTIONS TO 2-STAGE FURNACES MAY NOT
EXIST OR MAY ONLY BE A WIRE RATHER THAN A SCREW
TERMINAL.
Fig. 12—Typical 24-v Circuit Connections using Carrier Model DF Thermostat with Single- or 2-Stage Furnace
A97538
G
R
Y/Y2
O/W2
CARRIER
DUAL FUEL
THERMOSTAT
MODEL DF
SINGLE-STAGE
FURNACE
HEAT PUMP
G
Y
W
C
Y
R
O
W2
Y1/W2
C
B
L
S1
S2
R
C
FURNACE
COMPRESSOR
FAN
24 VAC HOT
24 VAC COM
N/A
RVS HEATING
RVS SENSING
OUTDOOR
SENSOR
CONNECTION
OUTDOOR
TEMPERATURE
SENSOR
W/W1
See note 7
RVS COOLING
G
R
Y/Y2
O/W2
CARRIER
DUAL FUEL
THERMOSTAT
MODEL DF
TWO-STAGE OR
VARIABLE SPEED
FURNACE
HEAT PUMP
G
C
Y
R
O
W2
Y1/W2
C
B
L
S1
S2
R
C
O
W2
Y1
FURNACE LO
COMPRESSOR
FAN
24 VAC HOT
24 VAC COM
FURNACE HI
RVS HEATING
RVS SENSING
OUTDOOR
SENSOR
CONNECTION
OUTDOOR
TEMPERATURE
SENSOR
W/W1
W/W1
Y/Y2
See notes 7 and 8
RVS COOLING
A97539
LEGEND
24-V FACTORY WIRING
24-V FIELD WIRING
FIELD SPLICE CONNECTION
OUTDOOR THERMOSTAT
EMERGENCY HEAT RELAY
SUPPLEMENTAL HEAT RELAY
SHR
EHR
ODT
A97413
9