LG LDC22720 Series, Service Manual

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7-1-5 Alarm for Open Door
1. This feature sounds a buzzer when the freezer or refrigerator door is not closed within 1 minute after it is opened.
2. One minute after the door is opened, the buzzer sounds three times each for ½ seconds. These tones repeat every
30 seconds.
3. The alarm is cancelled when the freezer or the refrigerator is closed while the buzzer sounds.
7-1-6 Buzzer Sound
When the button on the front Display is pushed, a Ding - Dong - sound is produced.
(Refer to the Buzzer Circuit 7-2-4 No. 3)
7-1-7 Defrosting (removing frost)
1.For initial power on or for restoring power, defrosting starts when the compressor running time reaches 4 hours.
2. Defrosting stops if the sensor temperature reaches 46.4°F (8°C) or more. If the sensor doesn’t reach 46.4°F(8°C) in
1 hour, the defrost mode is malfunctioning. (Refer to the defect diagnosis function, 7-1-9.)
3. Defrosting won’t function if its sensor is defective (wires are cut or short circuited)
7-1-8 Electrical Parts Are Turned On Sequentially
Electrical parts such as COMP, defrosting heater, freezer FAN, etc. Are turned on in the following order to prevent
noise and parts damage. Several parts are started at the same time at initial power on and are turned off together
when TEST is completed.
Closed Open Closed Open Closed
3 Times 3 Times 3 Times 3 Times
Within 1 min. 1 min.
30 sec 30 sec 30 sec
Freezer Door
or Refrigerator
Door
Buzzer
OPERATING ORDERS
In
iti
a
l p
o
w
e
r o
n
Temperature of Defrosting
Sensor is 45°C or more
(when unit is newly
purchased or when moved)
POWER
ON
In ½ second
COMP
ON
In ½ second
Freezer FAN
ON
In ½ second
Cooling FAN
ON
Temperature of defrosting
sensor is lower than 45°C
(when power cuts, SERVICE)
POWER
ON
In ½ second
Defrosting
heater ON
In 10 second
Defrosting
heater OFF
In ½ second
COMP
ON
In ½ second
Freezer FAN
ON
In ½ second
Cooling FAN
ON
Reset to normal operation
from TEST MODE
Total Load
OFF
In 7 minute COMP
ON
In ½ second Freezer FAN
ON
In ½ second Cooling FAN
ON