GE PSH23SGNAFBS Series, Technical Service Manual

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Rear
Front
Baffle
GEA01152
Housing
Fan
Motor
0.375"
1/2"
Air Flow
0.50" ± 0.05
Bracket
GEA01148
Condenser Fan
The fan is mounted in the machine compartment
with the No-Clean condenser. The fan and fan
shroud are mounted on one end of the condenser,
and the other end of the condenser is blocked.
When the fan is operating, air is pulled from the
center of the condenser, drawing air in through the
coils. The air is then exhausted over the
compressor and out the right side of the
refrigerator.
Inlet air is available through the left front and left
rear of the machine compartment. A rubber divider
strip underneath the refrigerator divides the inlet
and outlet sides of the machine compartment.
The rear access cover must be tightly fitted to
prevent air from being exhausted directly out of the
rear of the machine compartment, bypassing the
compressor.
The condenser fan is mounted with screws to a
fan shroud and mounting bracket that is attached
to the condenser.
Refer to the illustration for fan blade adjustment.
The condenser fan is the same permanent-
magnet, 4-pole, DC motor used in previous Arctica
models; however a significant difference is that the
fan will operate at 3 speeds. Fan speed (low,
medium, high) corresponds with compressor
speed to minimize pressure variations in the
sealed system. The speed of the fan is controlled
by the voltage output from the main control board.
Voltage output from the control board to the fan is
13.2 VDC; however to regulate the speed of the
fan, the main control board uses pulse width
modulation (PWM). When operating, voltage is
sent in pulses (much like a duty cycle) as opposed
to an uninterrupted flow. This pulsing of 13.2 VDC
produces effective voltage being received at the
motor, which is the equivalent to a reduction in
voltage. Fan speed will be selected and
maintained by the main control board regulating the
length and frequency of the 13.2 VDC pulse.