White Rodgers 850 Installation Instructions Manual page 3

4 MOUNTING AND WIRING
CONTINUED FROM SECOND PAGE
C ‡
Y
B O G
Fan
Relay
NOTE
For 2-wire Heat only,
attach to RH and W
Figure 2. Typical wiring diagram for
heat only, 3-wire, single transformer systems
C ‡
B O Y
Cooling
System
Figure 3. Typical wiring diagram for
cool only, 3-wire, single transformer systems
NOTE
RED jumper wire (provided with thermostat) must be
connected between thermostat RH and RC terminals
for proper thermostat operation with this system.
C ‡
B O Y
Cooling
System
Figure 4. Typical wiring diagram for
heat/cool, 4-wire, single transformer systems
‡
The 24 Volt neutral connection to terminal C on the
thermostat is not required if the batteries are replaced
once a year with fresh "AA" Energizer
JUMPER
WIRE
THERMOSTAT
W RC RH
SYSTEM
Heating
System
24 VAC
TRANSFORMER
JUMPER
WIRE
THERMOSTAT
G W RC RH
SYSTEM
Fan
Relay
Hot
24 VAC
120 VAC
Neutral
TRANSFORMER
JUMPER
WIRE
THERMOSTAT
G W RC RH
SYSTEM
Fan Heating
Relay System
Hot
24 VAC
120 VAC
Neutral
TRANSFORMER
®
alkaline batteries.
C ‡
B
Hot
120 VAC
Neutral
heat/cool, 5-wire, two-transformer systems
C ‡
B
Reversing
* Reversing valve is energized when the
system switch is in the COOL position
Figure 6. Typical wiring diagram for heat pump
with reversing valve energized in COOL
C ‡
Reversing
* Reversing valve is energized when the
system switch is in the HEAT position
Figure 7. Typical wiring diagram for heat pump
with reversing valve energized in HEAT
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O Y G W RC
Cooling Fan Heating
System Relay System
Figure 5. Typical wiring diagram for
JUMPER JUMPER
WIRE
O Y G W RC
Compressor Fan
Valve* Contactor Relay
JUMPER JUMPER
WIRE
B O Y G W RC
Compressor Fan
Valve* Contactor Relay
THERMOSTAT
RH
SYSTEM
Hot
24 VAC
120 VAC
Neutral
HEATING
TRANSFORMER
Hot
24 VAC
120 VAC
Neutral
COOLING TRANSFORMER
WIRE
THERMOSTAT
RH
SYSTEM
Hot
24 VAC 120 VAC
Neutral
TRANSFORMER
WIRE
THERMOSTAT
RH
SYSTEM
Hot
24 VAC
120 VAC
Neutral
TRANSFORMER