LG LRBN2051 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 1/2 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. 2)
7-1-7 Defrosting (removing frost)
1. Defrosting starts each time the COMPRESSOR running time reaches 7 hours.
2. For initial power on or for restoring power, defrosting starts when the compressor running time reaches 4 hours.
3. 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
2 hours, the defrost mode is malfunctioning. (Refer to the defect diagnosis function, 7-1-9.)
4. 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.
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Closed Open Closed Open
3 Times 3 Times 3 Times 3 Times
Closed
Within 1 min. 1 min.
30 sec 30 sec 30 sec
Freezer Door
or Refrigerator
Door
Buzzer
OPERATING ORDERS
Temperature of Defrosting
Sensor is 45°C or more
(when unit is newly
purchased or when moved)
Temperature of defrosting
sensor is lower than 45°C
(when power cuts, SERVICE)
Reset to normal operation
from TEST MODE
Initial power on
POWER
ON
in 1/2 second in 1/2 second
Total load
OFF
COMP
ON
Freezer FAN
ON
in 7 minute in 1/2 second
COMP
ON
Freezer FAN
ON
POWER
ON
COMP
ON
Freezer FAN
ON
Defrosting
heater ON
Defrosting
heater OFF
in 1/2 second
in 1/2 second in 1/2 second
in 10 second