LG LRDC20731ST, Service Manual

Page: 17 / 63

7-2 CONTROL METHOD ACCORDING TO FUNCTIONS
7-2-1 Start Position
1. After POWER OFF or Power Outage, check the EJECTOR's position with MICOM initialization to restart.
2. How to check if it is in place:
- Check HIGH/LOW signals from HALL SENSOR in MICOM PIN.
3. Control Method to check if it is in place:
(1) EJECTOR is in place,
- It is an initialized control, so the mode can be changed to ice making control.
(2) EJECTOR isn't in place:
A. If EJECTOR is back in place within 2 minutes with the motor on, it is being initialized. If not, go to Step B.
B. If EJECTOR is back in place within 18 minutes with the heater on (to control Heater on its OFF condition), it is being
initialized. If not, it is not functioning. Repeat Step B with Heater and Motor off.
7-2-2 Ice Making Mode
1. Ice Making control refers to the freezing of supplied water in the ice trays. Complete ice making operations by measuring
the temperature of the Tray with Ice-Making SENSOR.
2. Ice Making starts after completing fulfilled ice control and initial control.
3. The Ice Making function is completed when the sensor reaches 19°F(-7°C), 60 to 240 minutes after starting.
4. If the temperature sensor is defective, the ice-making function will be completed in 4 hours.
7-2-3 Harvest Mode
1. Ice-removing control refers to the operation of dropping cubes into the ice bin from the tray when ice-making has
completed.
2. Ice removing control mode:
(1) Operates Heater for 30 seconds; then operate MOTOR.
(2) After performing Step 1 (to control the Heater on its off condition), Ice-Removal control will be back in place wthin 18
minutes. (Hall SENSOR sign = OV). Ice removal is then complete. Then change the mode to the water supply control.
If this control phase fails to start, it is not functioning. Put the Heater and Motor in the off position. Restart every 2
hours. (Refer to fig.1)
NOTE : If the motor malfunctions and starts before the detect lever rises, MICOM regards the Ice-Removing phase as
completed. Water then starts flowing. To prevent this, MICOM doesn’t switch to water-supply mode, but restarts the ice-
removing mode. If this happens 3 times, the motor is malfunctioning and you should stop the loads (Heater, Motor). Then
restart the Ice-Removing mode every 2 hours. (See Step 2 above.)
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Heater
on
off
on
0V
5V
off
30 sec.
10 sec.
Motor
Hall IC
Ice removing
completion point
2 ms
Ice making sensor temperature is 50
°
F(10˚C)
or more
Max. 18 minutes
After detect LEVER rises
<fig1. Ice removing process>