Condenser Fan - GE PSH23PGR Series Technical Service Manual

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.
Rear
1/2"
Fan
0.375"
Air Flow
0.50" ± 0.05
Divider Strip
Front
Housing
Motor
Bracket
The rear access cover must be tightly fi tted 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.
Condenser fan speed corresponds with
compressor speed (low, medium, high) to
minimize pressure variations in the sealed
system except when the freezer temperature is
20°F above the set point. If this condition exists
(such as during initial startup), the condenser
fan operates at super high speed while the
compressor operates at medium speed.
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
13.6 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
fl ow. This pulsing of 13.6 VDC produces effective
voltage being received at the motor, which is
equivalent to a reduction in voltage.
Fan speed is selected and maintained by the
main control board regulating the length and
frequency of the 13.6 VDC pulse.
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