2015 White-Rodgers Product Catalog

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W905
Clip for
Hydronic
System
W904
Clip for
Celsius Display
W905
W904
ELEC GAS
Electric/Gas
Switch
W RH B RC
G O Y
CONFIGURATION AND
TYPICAL WIRING DIAGRAMS
RH Y
24 VAC 120 VAC
Hot
Neutral
THERMOSTAT
SYSTEM
G W
Cool only, 3-wire, single transformer systems
Cooling
System
Fan
Relay
RC O B
JUMPER
WIRE
RH Y
24 VAC 120 VAC
Hot
Neutral
THERMOSTAT
SYSTEM
G W
Heat only, 3-wire, single transformer systems
TRANSFORMER
Heating
System
Fan
Relay
RC
JUMPER
WIRE
For 2-wire Heat only
attach to RH and W
NOTE
O B
RH Y
24 VAC 120 VAC
Hot
Neutral
THERMOSTAT
SYSTEM
G W
Heat/cool, 4-wire, single transformer systems
TRANSFORMER
Heating
System
Fan
Relay
Cooling
System
RC
JUMPER
WIRE
RED jumper wire (provided
with thermostat) must be
connected between thermo-
stat's RH and RC terminals
for proper thermostat oper-
ation with this system.
NOTE
O B
RH Y
24 VAC 120 VAC
Hot
Neutral
THERMOSTAT
SYSTEM
G W
Heat/cool, 5-wire, two-transformer systems
HEATING TRANSFORMER
Heating
System
Fan
Relay
Cooling
System
RC
24 VAC 120 VAC
Hot
Neutral
COOLING TRANSFORMER
O B
RH Y
24 VAC 120 VAC
Hot
Neutral
THERMOSTAT
SYSTEM
G W
Heat pump with cool active reversing valve
TRANSFORMER
Reversing
Valve*
RC O B
JUMPER
WIRE
Compressor
Contactor
JUMPER
WIRE
* Reversing valve is energized when the
system switch is in the COOL position
Fan
Relay
RH Y
24 VAC 120 VAC
Hot
Neutral
THERMOSTAT
SYSTEM
G W
Heat pump with heat active reversing valve
TRANSFORMER
Reversing
Valve*
RC O B
JUMPER
WIRE
Compressor
Contactor
JUMPER
WIRE
* Reversing valve is energized when the
system switch is in the HEAT position
Fan
Relay
1F78-144
1F78-151
CONFIGURATION
TYPICAL WIRING DIAGRAMS
164
TECHNICAL HELP