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Temperature can cause some fan speed
variation. Fan speed can vary +/- 5%, depend-
ing on the temperature, with higher tempera-
tures causing slightly higher speeds.
Condenser fan speed is controlled by Pulse
Width Modulation (PWM), the same method
used to control fan speeds for the evaporators.
13.6 VDC
12 VDC
0 VDC
Super High Speed (12.0 VDC measured)
13.6 VDC
10.5 VDC
0 VDC
High Speed (10.5 VDC measured)
13.6 VDC
7.5 VDC
0 VDC
Medium Speed (7.5 VDC measured)
13.6 VDC
5.5 VDC
0 VDC
Low Speed (5.5 VDC measured)
Defrost Cycles
Fresh Food Evaporator Defrost Cycle
The refrigerator utilizes a forced air cycle defrost
method (no electric heater) to remove frost from
the fresh food evaporator. Fresh food air that is
above freezing temperature circulates thru the
coil and melts any accumulated frost. Note that
during fresh food defrost, the compressor may
still be running, cooling only the freezer section.
Fresh Food Normal Defrost
The fresh food section cools until the fresh food
thermistor is satisfied.
If both freezer and fresh food thermistors are
satisfi ed, the compressor cycles off. If the
freezer still requires cooling, the main control
board rotates the 3-way valve to stop refrigerant
flow to the fresh food evaporator. Even though
refrigerant flow has stopped in the fresh food
evaporator, the fresh food fan continues
to run at low speed.
The system is designed to run the fan until the
fresh food evaporator thermistor reaches 1°C.
Once this temperature is reached, the fan
continues to run for an additional 5 minutes.
Under normal conditions, the defrost time takes
approximately 30 minutes. The maximum time
the fan runs in low speed is 60 minutes. If the
evaporator thermistor has not reached 1°C after
60 minutes, the control switches to extended
defrost #1.
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