Evaporator Fan. GE Consumer & Industrial ZIC360NR, ZICS360NR

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Evaporator Fan. GE Consumer & Industrial ZIC360NR, ZICS360NR | Manualzz

Evaporator Fan

The position of the fan blade in relation to the shroud is important. Refer to illustration for specifications.

5/16 +/- .03

Airflow

The evaporator fan is the same fan used on previous models; however a significant difference is that the main control board does not require, nor receive, input from the fan feedback/rpm (blue) wire. The fan utilizes a permanent magnet, 4-pole, DC motor that operates at three different speeds: high, medium, and low. 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.

Temperature may cause some fan speed variation. Fan speed may vary +/- 5%, depending on the temperature, with higher temperatures causing slightly higher speeds.

13.2 VDC

12 VDC

0 VDC

13.2 VDC

9.2 VDC

0 VDC

13.2 VDC

8 VDC

0 VDC

High Speed (12 VDC measured)

Medium Speed (9.2 VDC measured)

Low Speed (8 VDC measured)

EVAPORATOR FAN SPEEDS

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If the fan shorts, it will damage the main control board. If the resistor on the main control board is burnt, you must replace the fan and the board (see photo).

Evaporator and Condenser Fan Resistors

Condenser Fan Resistor

Evaporator Fan Resistor

– 15 –

White Wire (DC Common)

The white wire is the DC common wire used for testing. During repairs, DC polarity must be observed. Reversing the DC polarity will cause a shorted motor and/or board.

Red Wire (Supply)

Each motor uses an internal electronic controller to operate the motor. Supply voltage from the main control board remains at a constant

12 VDC.

Blue Wire (Feedback/RPM)

The blue wire feeds rpm (speed) information to the main control board, allowing the board to maintain consistent fan speeds. Loss of feedback from the blue wire will result in the fan accelerating to maximum speed. Measure the fan rpm using the frequency between the blue and white wires.

High speed - 205 to 215 Hz (3140 RPM)

Medium speed - 155 to 165 Hz (2415 RPM)

Low speed - 140 to 150 Hz (2160 RPM)

Yellow Wire (Signal)

The yellow wire is the input wire from the main control board. The main control board provides

8 VDC effective voltage for low speed, 9.2 VDC effective voltage for medium speed, and 12 VDC for high speed. The fan will operate in low speed only when the fresh food thermistor is satisfied.

Note: When testing these motors:

• You cannot test with an ohmmeter.

• DC common is not AC common.

• Verify 2 voltage potentials:

a. Red to white - power for internal controller.

b. Yellow to white - power for fan.

• Observe circuit polarity.

• Motors can be run for short periods using a

9-volt battery. Connect the white wire to the

negative (-) battery terminal only. Connect the

red and yellow wires to the positive (+) battery

terminal.

Some of the low voltage DC connector labeling on this model may differ from other models. The function and diagnostics for these connectors are identical for all models.

J4 or J16 J3 or J10

J2 OR J13

J1 or J14

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