White Rodgers FC9s Up Section Ii Service And Maintenance Manual, UUM-A-0407, Motor Lubrication

269434-UUM-A-0407

Make sure you DO NOT move the clip on weight on the indoor fan wheel when cleaning the wheel. This weight is used to balance the wheel. Moving the weight will cause the fan wheel to vibrate.

Motor Lubrication

The motors in these furnaces are permanently lubricated, and do not require periodic oiling.

SECTION II: SERVICE AND MAINTENANCE MANUAL

SAFETY SECTION

The following safety rules must be followed when servicing the furnace.

ELECTRIC SHOCK, FIRE OR EXPLOSION HAZARD

Failure to follow safety warnings exactly could result in dangerous operation, serious injury, death or property damage.

Improper servicing could result in dangerous operation, serious injury, and death or property damage.

•Before servicing, disconnect all electrical power to the fur- nace.

•When servicing controls, label all wires prior to disconnect- ing. Reconnect wires correctly.

•Verify proper operation after servicing.

FURNACE MAINTENANCE SECTION

The furnace should be cleaned and adjusted by a certified dealer or qualified service contractor once a year or before the start of every heating season. The following items must be cleaned and serviced or replaced if there are signs of deterioration.

1.The vent terminal.

2.The furnace vent and combustion air intake passageways. Should it be necessary to service the vent/air intake system, the manufac- turer recommends this service be conducted by a qualified service agency. The operation of this appliance requires the reassembly and resealing of the vent/air intake system.

3.The furnace burners, ignitor and flame sensor.

4.The condensate collection and disposal system. If any disassem- bly of components containing flue or vent gases is required, a qualified service agency must perform the service.

SEQUENCE OF OPERATION

The following describes the sequence of operation of the furnace. Refer to Figure 1 for component location.

Continuous Blower

Cooling/heating thermostats have a fan switch that has an ON and AUTO position. In the ON position the thermostat circuit is completed between terminals R and G. The motor will operate on the speed tap selected on the Continuous Fan speed Jumper on the control board (HI COOL, LO COOL, or HEAT pins).

Intermittent Blower - Cooling

Cooling/heating thermostats have a fan switch that has an ON and AUTO position. In the AUTO position the thermostat circuit is completed between terminals R and G when there is a call for cooling. The motor will operate on the speed tap wire that is connected to the HI COOL ter- minal on the control board. When used with two-stage cooling units, the motor will operate on the speed tap connected to the LO COOL terminal when first stage cooling is operating. The motor will operate on the speed tap connected to the HI COOL terminal when second stage cool- ing is operating. The fan off setting is fixed at 60 seconds for SEER enhancement.

Heating Cycle

When the thermostat switch is set on HEAT and the fan is set on AUTO, and there is a call for heat, a circuit is completed between terminals R and W of the thermostat. When the proper amount of combustion air is being provided, the pressure switch will close, the ignition control pro- vides a 17-second warm-up period, the gas valve then opens, the gas starts to flow, ignition occurs and the flame sensor begins its sensing function. The blower motor will energize 30 seconds after the gas valve opens, if a flame is detected. Normal furnace operation will continue until the thermostat circuit between R and W is opened, which causes the ignition system and gas valve to de-energize and the burner flames to be extinguished. The vent motor will operate for an additional 15 sec- onds and the blower motor will operate for the amount of time set by the fan-off delay jumper located on the control board. See Figure 6. The heating cycle is complete, and ready for the start of the next heating cycle.

CONTINUOUS		TWIN
FAN SPEED
JUMPER
FAN OFF		120	90
	Y1Y/Y2	DELAY 180	REMOTE SWITCH 60 BLOWER OFF	HEAT HICOOL	LOCOOL
ADJUSTMENT
JUMPER
	W			FAN SPEED	CONT
	R
	G
	C

PARK PARK LO COOL

HI COOL

HEAT

EAC-H

L1

XFMR

NEUTRALS

RED-LOW YELLOW-MED. LOW BLACK-HI

BLUE-MED. HI

FIGURE 6: Furnace Control Board

HUM

Unitary Products Group 5