White Rodgers 750 Check Thermostat Operation, Fan Operation, Heating System, Mounting And Wiring

4 MOUNTING AND WIRING

CONTINUED FROM SECOND PAGE

						JUMPER
						WIRE
	B	O	Y	G	W	RC RH		THERMOSTAT
									SYSTEM
				Fan	Heating
				Relay	System					Hot
	NOTE					24 VAC				120 VAC
For 2-wire Heat only,										Neutral
attach to RH and W							TRANSFORMER

Figure 2. Typical wiring diagram for

heat only, 3-wire, single transformer systems

B O Y G W

Cooling	Fan	Heating
System	Relay	System

RC RH		THERMOSTAT
				SYSTEM
					Hot
24 VAC					120 VAC
					Neutral
			HEATING
	TRANSFORMER
24 VAC					Hot
					120 VAC
					Neutral

COOLING TRANSFORMER

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

Figure 4. Typical wiring diagram for

heat/cool, 4-wire, single transformer systems

Figure 5. Typical wiring diagram for

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

JUMPER JUMPER

WIREWIRE

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

WIREWIRE

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

with reversing valve energized in HEAT

5 CHECK THERMOSTAT OPERATION

NOTE

To prevent static discharge problems, touch side of ther- mostat to release static build-up before touching any keys.

If at any time during testing your system does not operate properly, contact a qualified serviceperson.

Fan Operation

If your system does not have a G terminal connection, skip to Heating System.

1.Turn on power to the system.

2.Move FAN switch to ON position. The blower should begin to operate.

3.Move FAN switch to AUTO position. The blower should stop immediately.

!CAUTION

To prevent compressor and/or property damage, if the outdoor temperature is below 50° F, DO NOT operate the cooling system.

This thermostat has a time delay between cooling cycles to allow the head pressure in the compressor to stabilize. If the tempera- ture is adjusted to call for cool within 5 minutes of the last cycle the snowflake icon will blink indicating the thermostat is locked out. After 3 to 5 minutes, the compressor will start and the snowflake icon will stop flashing. This helps prevent the compressor from cycling too quickly and is normal operation for the thermostat.

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 temperature setting above room tem- perature. The cooling system should stop operating.

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.

www.white-rodgers.com