Wiring Diagram; Heating System; Cooling System - White Rodgers 1F87-251 Installation And Operation Instructions Manual

B O Y 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
Y
B O G
Cooling Fan
System Relay
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.
Y
B O G
Cooling Fan
System Relay
Figure 4. Typical wiring diagram for
heat/cool, 4-wire, single transformer systems

Heating System

1. Move SYSTEM switch to HEAT position. If the heating
system has a standing pilot, be sure to light it.
2. Press to adjust thermostat setting above room tempera-
ture. The heating system should begin to operate.
3. Press to adjust temperature setting below room tem-
perature. The heating system should stop operating.
JUMPER
WIRE
THERMOSTAT
W RC RH
SYSTEM
Heating
System
Hot
24 VAC
120 VAC
Neutral
TRANSFORMER
(Class II Current Limited)
JUMPER
WIRE
THERMOSTAT
W RC RH
SYSTEM
Hot
24 VAC
120 VAC
Neutral
TRANSFORMER
(Class II Current Limited)
JUMPER
WIRE
THERMOSTAT
W RC RH
SYSTEM
Heating
System
Hot
24 VAC
120 VAC
Neutral
TRANSFORMER
(Class II Current Limited)
Y
B O
Cooling
System Relay
Figure 5. Typical wiring diagram for
heat/cool, 5-wire, two-transformer systems
B O Y
Reversing Compressor
Valve* Contactor
* 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
B O Y
Reversing Compressor
Valve* Contactor
* 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

Cooling System

!
To prevent compressor and/or property damage, if the
outdoor temperature is below 50°F, DO NOT operate
the cooling system.
1. Move SYSTEM switch to COOL position.
2. Press to adjust thermostat setting below room tem-
perature. The blower should come on immediately on high
speed, followed by cold air circulation
3. Press to adjust temperature setting above room tem-
perature. The cooling system should stop operating.
3
THERMOSTAT
G W RC RH
SYSTEM
Fan Heating
24 VAC
System
HEATING TRANSFORMER
(Class II Current Limited)
24 VAC
COOLING TRANSFORMER
(Class II Current Limited)
JUMPER JUMPER
WIRE WIRE
THERMOSTAT
G W RC RH
SYSTEM
Fan
Relay
24 VAC
TRANSFORMER
(Class II Current Limited)
JUMPER JUMPER
WIRE WIRE
THERMOSTAT
G W RC RH
SYSTEM
Fan
Relay
24 VAC
TRANSFORMER
(Class II Current Limited)
CAUTION
Hot
120 VAC
Neutral
Hot
120 VAC
Neutral
Hot
120 VAC
Neutral
Hot
120 VAC
Neutral