Friedrich 2008, 2009 Functional Component Definitions, EQ08 System Control Switch Test

SYSTEM CONTROL SWITCH - TEST (See Figure 15) Disconnect leads from control switch. There must be continuity as follows:

1.“Off” Position - no continuity between terminals.

2.“Lo Cool” Position - between terminals “L1” and “C,” “LO” and “MS.”

3.“Med Cool” Position - between terminals “L1” and “C,” “M” and “MS.”

4.“Hi Cool” Position - between terminals “L1” and “C,” “H” and “MS.”

5.“Fan Only” Position - between terminals “L1” and “2.”

Figure 15

System Control Switch

“EQ08” SYSTEM CONTROL SWITCH – TEST

(See Figure 16)

Turn knob to phase of switch to be tested. There must be continuity as follows:

1.“Fan Only” Position – between terminals “MS” and “H”

2.“Hi Cool” Position – between terminals “L1” and “C” and “MS” and “H”

3.“Low Cool” Position – between terminals “L1” and “C” and “MS” and “LO”

4.“Low Heat” Position – between terminals “L2” and “2” and “MS” and “LO”

5.“Hi Heat” Position – between terminals “L2” and “2” and “MS” and “H”

Figure 16			L1
System Control Switch
(EQ Models)			B1
	MS		L2
		H	C
		LO	2

FUNCTIONAL COMPONENT DEFINITIONS

MECHANICAL COMPONENTS

Bellows condensate valve Temperature-sensitive valve that opens up to drain off condensate water when the outside temperature falls below 40°F and closes when the outside temperature reaches 58°F.

Vent door Allows introduction of fresh air into the room and/or exhausts stale room air outside (on select models.)

Plenum assembly Diffuser with directional louvers used to direct the conditioned airflow.

Blower wheel Attaches to the indoor side of the fan motor shaft and is used for distributing unconditioned, room side air though the heat exchanger and delivering conditioned air into the room.

Slinger fan blade Attaches to the outdoor side of the fan motor shaft and is used to move outside air through the condenser coil, while slinging condensate water out of the base pan and onto the condenser coil, thus lowering the temperature and pressures within the coil.

ELECTRICAL COMPONENTS

Thermostat Used to maintain the specified room side comfort level

System switch Used to regulate the operation of the fan motor, the compressor or to turn the unit off. For troubleshoot- ing, refer to the wiring diagrams and schematics in the back of this service manual.

Capacitor Reduces line current and steadies the voltage supply, while greatly improving the torque characteristics of the fan motor and compressor motor.

Defrost thermostat (Heatpumps only) A dual purpose control that acts as an outdoor thermostat and defrost control.

Smart Fan Automatically adjusts the fan speed to main- tain the desired room temp.

MoneySaver® switch When engaged, it sends the power supply to the fan motor through the thermostat, which allows for a cycle-fan operation.

Fan Motor Dual-shafted fan motor operates the indoor blower wheel and the condenser fan blade simultaneously.

Solenoid Used to energize the reversing valve on all heat pump units.

Heating element Electric resistance heater, available in 3.3, 4.0 or 5.2 kW on select TwinTemp® models.

Heat anticipator Used to provide better thermostat and room air temperature control.

HERMETIC COMPONENTS

Compressor Motorized device used to compress refrigerant through the sealed system.

Reversing valve A four-way switching device used on all heat pump models to change the flow of refrigerant to permit heating or cooling.

Check valve A pressure-operated device used to direct the flow of refrigerant to the proper capillary tube, during either the heating or cooling cycle.

Capillary tube A cylindrical meter device used to evenly dis- tribute the flow of refrigerant to the heat exchangers (coils.)

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