Testing The Fan In The Middle Divider (Cwb8420Dz); Testing The Heater Fan (Cwb8420Dz); Testing The Ptc Heater (Cwb8420Dz) - EdgeStar CWB8420DZ Service Manual

2. To Check The Evaporator Fan Motor:
Disconnect the unit from the power source.
Remove the cabinet back panel.
Disconnect the evaporator fan motor connector from the cable.
Connect the fan motor to a 12V DC power source. If the fan fails to operate, it is defective
and must be replaced.

9.4.4 Testing the Fan in the Middle Divider (CWB8420DZ)

1. This fan motor operates independent from the compressor. When the set temperature of
lower zone is not met and is lower than the actual storage temperature the fan runs. The rest
of the time it does not run. If the set temperature of lower zone is not met and lower than the
actual storage temperature but the fan motor doesn't operate, the motor is either defective or
disconnected. If neither operates, check the Power PCB and the cabinet wiring.
2. To Check The Fan Motor in Middle Divider:
Disconnect the unit from the power source.
Remove the top panel of the middle divider.
Disconnect the fan motor connector from the cable.
Connect the motor to a 12V DC power source. If the motor fails to operate, it is defective
and must be replaced.

9.4.5 Testing the Heater Fan (CWB8420DZ)

1. The heater fan motor operates when the PTC heater operates and at the rest time it cycles
ON and OFF to circulate the interior air.
the motor is either defective or disconnected. If neither operates, check the Power PCB and
the cabinet wiring.
2. To Check The Heater Fan Motor,
Disconnect the unit from the power source.
Remove the bottom zone back panel.
Disconnect the heater fan motor connector from the cable.
Connect the motor to a 12V DC power source. If the motor fails to operate, it is defective
and must be replaced.

9.4.6 Testing the PTC Heater (CWB8420DZ)

1. The PTC heater operates when the set temperature is not met and is higher than the actual
lower cabinet temperature. If not, the PTC heater is either defective or disconnected. Always
check the Power PCB and the cabinet wiring.
2. To Check The PTC Heater,
Disconnect the unit from the power source.
Remove the bottom zone back panel.
Disconnect the PTC connector from the cable.
Connect the PTC heater to the rated power source on the rating label. If the PTC
heater fails to operate, it is defective and must be replaced.
If the PTC heater runs but the fan motor doesn't,