White Rodgers 875 Heating System, Cooling System, Typical wiring diagram for, Thermostat, Relay

C‡ B O

NOTE

For 2-wire Heat only, attach to RH and W

			JUMPER
			WIRE
Y	G	W	RC RH	THERMOSTAT
				SYSTEM
	Fan	Heating
	Relay	System		Hot
			24 VAC	120 VAC
				Neutral
			TRANSFORMER

THERMOSTAT

C‡ B O Y G W RC RH

Cooling	Fan	Heating
System	Relay	System

	SYSTEM
		Hot
24 VAC		120 VAC
		Neutral

HEATING

TRANSFORMER

24 VAC	Hot
	120 VAC

Figure 2. Typical wiring diagram for

heat only, 3-wire, single transformer systems

JUMPER

WIRE

C‡

B

O

Y

G

W

RC

RH

THERMOSTAT

SYSTEM

Cooling

Fan

System

Relay

Hot

24 VAC

120 VAC

Neutral

TRANSFORMER

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

JUMPER

for proper thermostat operation with this system.

WIRE

C‡

B

O

Y

G

W

RC

RH

THERMOSTAT

SYSTEM

Cooling

Fan

Heating

System

Relay

System

Hot

24 VAC

120 VAC

Neutral

TRANSFORMER

Neutral

COOLING TRANSFORMER

Figure 5. Typical wiring diagram for

heat/cool, 5-wire, two-transformer systems

JUMPER JUMPER

WIREWIRE

C‡	B O		Y	G	W	RC RH	THERMOSTAT
							SYSTEM
	Reversing	Compressor		Fan
	Valve*		Contactor	Relay			Hot
						24 VAC	120 VAC
	* Reversing valve is energized when the						Neutral
	system switch is in the COOL position					TRANSFORMER
Figure 6. Typical wiring diagram for heat pump
	with reversing valve energized in COOL
			JUMPER			JUMPER
			WIRE			WIRE
C‡	B O		Y	G	W	RC RH	THERMOSTAT
							SYSTEM
	Reversing	Compressor		Fan
	Valve*		Contactor	Relay			Hot
						24 VAC	120 VAC
	* Reversing valve is energized when the						Neutral
	system switch is in the HEAT position					TRANSFORMER

Figure 7. Typical wiring diagram for heat pump

Figure 4. Typical wiring diagram forwith reversing valve energized in HEAT 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” alkaline batteries.

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 thermostat setting below room tempera- ture. The heating system should stop operating.

Cooling System

!CAUTION

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 tempera- ture.The blower should come on immediately on high speed, followed by cold air circulation

3.Press to adjust thermostat setting above room tempera- ture. The cooling system should stop operating.

3