LG LRDN22734WW, LRDN22734TT, LRDN22734ST, LRDN22734SB Service Manual

REFRIGERATOR
SERVICE MANUAL
CAUTION
BEFORE SERVICING THE UNIT, READ THE SAFETY PRECAUTIONS IN THIS MANUAL.
Models:
LRDN22734SB LRDN22734ST LRDN22734TT LRDN22734WW
CONTENTS
DESCRIPTION OF FUNCTION & CICUIT OF MICOM (GOOD, BETTER) ..................................................................... 45-64
REFRIGERATOR EXPLODED VIEW & SERVICE PARTS LIST.......................................................................................65-102
SAFETY PRECAUTIONS ....................................................................................................................................................... 2
SPECIFICATIONS................................................................................................................................................................... 3
PARTS IDENTIFICATION.................................................................................................................................................... 4-7
DISASSEMBLY.................................................................................................................................................................... 8-9
DOOR................................................................................................................................................................................... 8
DOOR SWITCH.................................................................................................................................................................... 8
FAN AND FAN MOTOR........................................................................................................................................................ 9
DEFROST CONTROL ASSEMBLY...................................................................................................................................... 9
LAMP.................................................................................................................................................................................... 9
CONTROL BOX-REFRIGERATOR...................................................................................................................................... 9
MULTI DUCT ........................................................................................................................................................................ 9
ADJUSTMENT.................................................................................................................................................................. 10-11
COMPRESSOR.................................................................................................................................................................. 10
PTC-STARTER.................................................................................................................................................................. 10
OLP (OVERLOAD PROTECTOR)....................................................................................................................................... 11
TO REMOVE THE COVER PTC..........................................................................................................................................11
CIRCUIT DIAGRAM.......................................................................................................................................................... 12-13
TROUBLESHOOTING...................................................................................................................................................... 14-19
COMPRESSOR AND ELECTRIC COMPONENTS ........................................................................................................... 14
PTC AND OLP.................................................................................................................................................................... 15
OTHER ELECTRICAL COMPONENTS............................................................................................................................. 16
SERVICE DIAGNOSIS CHART.......................................................................................................................................... 17
REFRIGERATION CYCLE ............................................................................................................................................ 18-19
OPERATION PRINCIPLE & REPAIR METHOD OF ICEMAKER .................................................................................. 20-23
DESCRIPTION OF FUNCTION & CIRCUIT OF MICOM (BEST, DISPENSER) ............................................................. 24-44
SAFETY PRECAUTIONS
Please read the following instructions before servicing your refrigerator.
1. Check the refrigerator for electrical faults.
2. To prevent electric shock, unplug before servicing.
3. Always check line voltage and amperage.
4. Use standard electrical components.
5. Don't touch metal products in the freezer with wet hands. This may cause frostbite or cause your skin to freeze and stick to the surfaces inside the freezer.
6. Prevent water from flowing onto electric elements in the mechanical parts.
7. Close the top door before opening the bottom door. Otherwise, you might hit your head when you stand up.
8. When tilting the refrigerator, remove any materials on the refrigerator, especially the glass shelves and stored foods.
9. When servicing the evaporator, wear cotton gloves. This is to prevent injuries from the sharp evaporator fins.
10. Disassembly, repair, and servicing the sealed refrigeration system should be performed only by qualified and certified personnel. Refrigerant should not be vented into the atmosphere; proper recovery equipment should be used.
- 2 -
1. SPECIFICATIONS
20 cu. ft. / 22 cu. ft.
ITEMS SPECIFICATIONS
DOOR DESIGN Side Rounded
3
29 7/
8 X 31
DIMENSIONS (inches)
NET WEIGHT (pounds)
COOLING SYSTEM Fan Cooling
TEMPERATURE CONTROL Micom Control
DEFROSTING SYSTEM
DOOR FINISH Embossed Metal, VCM, Stainless
HANDLE TYPE Bar, Al
INNER CASE ABS Resin
INSULATION Polyurethane Foam
32 7/8 X 31 3/4 X 69 1/2 (WX
32 7/8 X 31 3/4 X 68 1/2 (WX
238.4 (
246.9 (
Full Automatic
Heater Defrost
/
4 X 67
20cu.ft)
22cu.ft)
7
/
8 (WXDXH) 20cu.ft
DXH) 22cu.ft Dispenser
DXH) 22cu.ft
ITEMS SPECIFICATIONS
VEGETABLE TRAY Opaque Drawer Type
COMPRESSOR PTC Starting Type
EVAPORATOR Fin Tube Type
CONDENSER Wire Condenser
REFRIGERANT R-134a (115 g)
LUBRICATING OIL Freol @ 10G (310 cc)
DEFROSTING DEVICE SHEATH HEATER
REFRIGERATOR 60 W (2EA)
LAMP
FREEZER 60 W (2EA)
- 3 -
2. PARTS IDENTIFICATION
- 4 -
PARTS AND FEATURES
A
B
C
D
E
F
G
H
K
L
M
N
O
P
Q
I
J
R
NOTE:This guide covers several different models.The refrigerator you have purchased may have some or all of the items listed below. The locations of the features shown below may not match your model.
A
Digital Sensor Control
B
Refrigerator Light
C
Shelves
D
Chef Fresh / Snack Pan*
E
Can Dispenser*
F
Optibin Crisper Keeps fruits and vegetable fresh and crisper
G
Customcube Icemaker
H
Ice Bin
I
Durabase
J
Divider
K
Filter (inside)*
L
Dairy Bin
M
Design-A-Door
N
Egg Box
O
Refrigerator Door Rack
Freezer Light
P
Wire Basket
Q
Freezer Door Rack (Tilting*)
R
*on some models
PARTS AND FEATURES
- 5 -
A
B
C
D
E
F
G
H
K
L
M
N
O
P
Q
I
J
R
NOTE:This guide covers several different models.The refrigerator you have purchased may have some or all of the items listed below. The locations of the features shown below may not match your model.
A
Digital Sensor Control
B
Refrigerator Light
C
Shelves
D
Chef Fresh / Snack Pan*
E
Can Dispenser*
F
Optibin Crisper Keeps fruits and vegetable fresh and crisper
G
Triple Ice Tray
H
Ice Bin
I
Durabase
J
Divider
K
Filter (inside)*
L
Dairy Bin
M
Design-A-Door
N
Egg Box
O
Refrigerator Door Rack
Freezer Light
P
Wire Basket
Q
Freezer Door Rack (Tilting*)
R
*on some models
PARTS AND FEATURES
- 6 -
A
B
C
D
E
F
G
H
J
K
L
M
N
O
I
P
NOTE:This guide covers several different models.The refrigerator you have purchased may have some or all of the items listed below. The locations of the features shown below may not match your model.
I
Divider
J
Dairy Bin
K
Design-A-Door
L
Egg Box
Refrigerator Door Rack
M
Freezer Light
N
Wire Basket
O
Freezer Wire Door Rack
P
Digital Sensor Control
A B
Refrigerator Light
C
Shelves
D
Snack Pan
E
Optibin Crisper Keeps fruits and vegetable fresh and crisp
Triple Twist Ice Tray
F
G
Ice Bin
H
Wire Durabase
PARTS AND FEATURES
- 7 -
A
B
C
D
E
F
G
H
I
J
K
L
M
N
NOTE:This guide covers several different models.The refrigerator you have purchased may have some or all of the items listed below. The locations of the features shown below may not match your model.
I
Dairy Bin
J
Design-A-Door
K
Wire Freezer Shelf
L
Refrigerator Door Rack
Freezer Light
M
Freezer Door Rack
N
Digital Sensor Control
A B
Refrigerator Light
C
Shelves
D
Snack Pan
E
Optibin Crisper Keeps fruits and vegetable fresh and crisp
Ice Trays
F
G
Ice Bin
H
Wire Durabase
3. DISASSEMBLY
BOLT
HINGE
HINGE COVER
GASKET
LOWER HINGE
BOLT
DOOR SWITCH
LEAD WIRE
3-1 DOOR
Refrigerator Door
1. Remove the hinge cover by pulling it upwards.
2. Loosen the hexagonal bolts attaching the upper hinge to the body and lift the freezer door.
Figure 1
3. Pull out the door gasket to remove from the door foam assembly.
Freezer Door
1. Loosen the hexagonal bolts attaching the lower hinge to the body to remove the refrigerator door only.
Figure 3
2. Pull out the door gasket to remove from the door foam assembly.
3-2 DOOR SWITCH
1. To remove the door switch, pry it out with a slotted-type driver, as shown in (Figure 4).
2. Disconnect the lead wire from the switch.
Figure 2
Figure 4
- 8 -
3-3 FAN AND FAN MOTOR
FAN
BRACKET
MOTOR
GRILLE
FAN MOTOR
GRILLE ASSEMBLY
DEFROST-CONTROL ASSEMBLY
CONTROL BOX
COVER LAMP
1. Remove the freezer shelf. (If your refrigerator has an icemaker, remove the icemaker first)
2. Remove the grille by pulling it out and by loosening a screw.
3. Remove the Fan Motor assembly by loosening 2 screws and disassemble the shroud.
4. Pull out the fan and separate the Fan Motor and Bracket.
Figure 5
3-4 DEFROST CONTROL ASSEMBLY
Defrost Control assembly consists of Defrost Sensor and FUSE–M.
The Defrost Sensor works to defrost automatically. It is attached to the metal side of the Evaporator and senses its temperature. At 72°C, it turns the Defrost Heater off.
Fuse-M is a safety device for preventing over-heating of the Heater when defrosting.
1. Pull out the grille assembly. (Figure 6)
2. Separate the connector with the Defrost Control assembly and replace the Defrost Control assembly after cutting the Tie Wrap. (Figure 7)
3-5-1 Refrigerator Compartment Lamp
1. Unplug the power cord from the outlet.
2. Remove refrigerator shelves.
3. Release the hooks on both ends of the lamp shield and pull the shield downward to remove it.
4. Turn the lamp counterclockwise.
5. Assemble in reverse order of disassembly. Replacement bulb must be the same specification as the original (Max. 60 W-2EA).
Figure 9
3-5-2 Freezer Compartment Lamp
1. Unplug refrigerator or disconnect power.
2. Reach behind light shield to remove bulb.
3. Replace bulb with a 60-watt appliance bulb.
4. Plug in refrigerator or reconnect power.
3-6 CONTROL BOX-REFRIGERATOR
1. First, remove all shelves in the refrigerator, than remove the Refrigerator control Box by loosening 2 screws.
Figure 10
3-5 LAMP
Figure 6
Figure 7
Figure 8
2. Remove the Refrigerator Control Box by pulling it downward.
3. Disconnect the lead wire on the right position and separate the lamp sockets.
3-7 MULTI DUCT
1. Remove an upper and lower Cap by using a flat screwdriver, and loosen 3 screws. (Figure 11)
2. Disconnect the lead wire on the bottom position.
Figure 11
- 9 -
4. ADJUSTMENT
PTC STARTER
SEALED TERMINAL
COMPRESSOR MOTOR
C
M
S
M
3
6
5
2
S
PTC
N
L1
OVERLOAD PROTECTOR
Resistance Starter Capacitor Running
4-1 COMPRESSOR
4-1-1 Role
The compressor intakes low temperature and low pressure gas from the evaporator of the refrigerator and compresses this gas to high-temperature and high-pressure gas. It then delivers the gas to the condenser.
4-1-2 Composition
The compressor includes overload protection. The PTC starter and OLP (overload protector) are attached to the outside of the compressor. Since the compressor is manufactured to tolerances of 1 micron and is hermetically sealed in a dust and moisture-free environment, use extreme caution when repairing it.
4-1-3 Note for Usage
(1) Be careful not to allow over-voltage and over-current. (2) If compressor is dropped or handled carelessly, poor
operation and noise may result.
(3) Use proper electric components appropriate to the
Particular Compressor in your product.
(4) Keep Compressor dry.
If the Compressor gets wet (in the rain or a damp environment) and rust forms in the pin of the Hermetic Terminal, poor operation and contact may result.
(5) When replacing the Compressor, be careful that dust,
humidity, and soldering flux don’t contaminate the inside of the compressor. Dust, humidity, and solder flux contaminate the cylinder and may cause noise, improper operation or even cause it to lock up.
4-2 PTC-STARTER
4-2-1 Composition of PTC-Starter
(1) PTC (Positive Temperature Coefficient) is a no-contact
semiconductor starting device which uses ceramic material consisting of BaTiO
(2) The higher the temperature is, the higher the resistance
value. These features are used as a starting device for the Motor.
4-2-2 Role of PTC-Starter
(1) The PTC is attached to the Sealed Compressor and is
used for starting the Motor.
(2) The compressor is a single-phase induction motor.
Durign the starting operation, the PTC allows current flow to both the start winding and main winding.
4-2-3 PTC-Applied Circuit Diagram
Starting Method for the Motor
Figure 12
4-2-4 Motor Restarting and PTC Cooling
(1) It requires approximately 5 minutes for the pressure to
equalize before the compressor can restart.
(2) The PTC device generates heat during operation.
Therefore, it must be allowed to cool before the compressor can restart.
4-2-5 Relation of PTC-Starter and OLP
(1) If the compressor attempts to restart before the PTC
device is cooled, the PTC device will allow current to flow only to the main winding.
(2) The OLP will open because of the over current
condition. This same process will continue (3 to 5 times) when the compressor attempts to restart until the PTC device has cooled. The correct OLP must be properly attached to prevent damage to the compressor. Parts may appear physically identical but could have different electrical ratings. Replace parts by part
3.
number and model number. Using an incorrect part could result in damage to the product, fire, injury, or possibly death.
4-2-6 Note for Using the PTC-Starter
(1) Be careful not to allow over-voltage and over-current. (2) Do not drop or handle carelessly. (3) Keep away from any liquid.
If liquid such as oil or water enters the PTC, PTC materials may fail due to breakdown of their insulating capabilities.
(4) If the exterior of the PTC is damaged, the resistance
value may be altered. This can cause damage to the compressor and result in a no-start or hard-to-start condition.
(5) Always use the PTC designed for the compressor and
make sure it is properly attached to the compressor. Parts may appear physically identical but could have different electrical ratings. Replace parts by part number and model number. Using an incorrect part could result in damage to the product, fire, injury, or possibly death.
- 10 -
4-3 OLP (OVERLOAD PROTECTOR)
Part
Customer part number
Lot code/ date code
330 FBYY -S1 BOX98
12345678
Physical termination part number
Electrical
characteristics
part number
No. Name
Base, phenolic (UL 94 V-0 rated) Movable arm support, plated steel Stationary contact support, plated steel Heater support, plated steel Heater, resistance alloy Disc, thermostatic alloy Movable arm, spring temper copper alloy Contact, movable, silver on copper Contact, stationary, silver on copper Slug, plated steel Cover, polyester (UL 94 V -0 rated) Pin connector, plated copper alloy (To engage 2.33/2.66 mm dia. pin) Quick-connect terminal, brass, conforms to UL 310, MEMA DC-2, DIN 46344
(OVERLOAD PROTECTOR cross section)
1
2
4-3-1 Definition of OLP
(1) OLP (OVERLOAD PROTECTOR) is attached to the
Compressor and protects the Motor by opening the circuit to the Motor if the temperature rises and activating the bimetal spring in the OLP.
(2) When high current flows to the Compressor motor, the
Bimetal works by heating the heater inside the OLP, and the OLP protects the Motor by cutting off the current flowing to the Compressor Motor.
4-3-2 Role of the OLP
(1) The OLP is attached to the Sealed Compressor used
for the Refrigerator. It prevents the Motor Coil from being started in the Compressor.
(2) For normal operation of the OLP, do not turn the Adjust
Screw of the OLP in any way.
4-4 TO REMOVE THE COVER PTC
1) Remove the Cover Back M/C.
(2) Remove the screw on Cover PTC.
Figure 13
(3) Remove two Housings on upper part of Cover PTC.
(4) Take out the cover PTC from upper to lower position
like .
(5) Turn 45° in the direction of and take it out.
(6) Assembly in reverse order of disassembly.
- 11 -
5. CIRCUIT DIAGRAM
5. CIRCUIT DIAGRAM
- 12 -
Best / Best dispenser
GY: GRIS/GRAY
Good / Better
- 13 -
GY: GRIS/GRAY
6. TROUBLESHOOTING
1
2
3
4
5
2
5
5
3
5
4
5
5
1
43
YES
YES
The range of resistance is between 1~50Ω (OK)
Not open
4.5~9
Open
Open or short
Open or short
YES
YES
NO
NO
NO
6-1 COMPRESSOR AND ELECTRIC COMPONENTS
Power Source.
Remove PTC-Starter from Compressor and measure voltage between Terminal C of Compressor and Terminals 5 or 6 of PTC.
No Voltage.
Applied voltage isn't in range of Rating Voltage ±10%.
(Reated Voltage ±10%)?
OLP disconnected?
Advise customer that power supply needs to be checked by an electrician.
Replace OLP.
Check connection condition.
Reconnect.
Check resistance of Motor Compressor.
Check resistance of PTC-Starter.
Check resistance between M-C, S-C and M-S in Motor Compressor.
Check resistance of two terminals in PTC-Starter.
Replace Compressor.
Replace PTC-Starter.
Check OLP.
Check starting state.
Check resistance of two terminals in OLP.
Check the power supply under load. (Compressor attempting to re-start after being off for 5 minutes).
Supply voltage rating with ±10%.
Replace OLP.
Did compressor start?
Compressor is OK
Replace the compressor
- 14 -
6-2 PTC AND OLP
65
Shows continuity
Open
Normal operation of Compressor is impossible or poor.
Separate PTC-Starter from Compressor and measure resistance between No. 5 and 6 of PTC-Starter with a Tester. (Figure 14)
Separate OLP from Compressor and check resistance value between two terminals of OLP with a Tester. (Figure 15)
Observation value is 115V/60Hz : 6.8Ω±30%
The resistance value is 0(short) or (open).
Check another electric component.
Replace OLP.
Replace PTC­Starter.
Figure 14
Figure 15
- 15 -
6-3 OTHER ELECTRICAL COMPONENTS
Not cooling at all
Compressor doesn't run.
Poor cooling performance
Compressor runs poorly.
Check for open short or incorrect resistance readings in the following components
a. Starting devices
b. OLP
c. Compressor coil
d. Wiring harness
Check starting voltage.
Check voltage at starting devices.
Cause
Short, open, or broken.
Poor contact or shorted.
Coil open or shorted.
Poor contact or shorted.
Low voltage.
Poor or broken or open contact.
Replace indicated component.
Advise customer that the Power supply needs to be checked by an electrician.
Replace indicated component.
Fan motor doesn't run.
Heavy frost buildup on EVAPORATOR.
Check current flowing in sub-coil of Compressor.
Check rating of OLP.
Check wiring circuit.
Check Fan Motor.
Check current flow in the following components: Sensor Fuse-M
Check current flow in the Defrost Heater.
Shorted.
Lack of capacity.
Wire is open or shorted.
Coil is shorted or open.
Open.
Open.
Replace indicated component.
Replace indicated component.
Replace Defrost Heater.
- 16 -
6-4 SERVICE DIAGNOSIS CHART
COMPLAINT POINTS TO BE CHECKED REMEDY
No Cooling.
Cools poorly.
Foods in the Refrigerator are frozen.
Condensartion or ice forms inside the unit.
Condensartion forms in the Exterior Case.
There is abnormal noise.
Is the power cord unplugged from the outlet?
Check if the power switch is set to OFF.
Check if the fuse of the power switch is shorted.
Measure the voltage of the power outlet.
Check if the unit is placed too close to the wall.
Check if the unit is placed too close to the stove,
gas cooker, or in direct sunlight.
Is the ambient temperature too high or the room door closed?
Check if food put in the refrigerator is hot.
Did you open the door of the unit too often
or check if the door is sealed properly?
Check if the Control is set to Warm position.
Is food placed in the cooling air outlet?
Check if the control is set to colder position.
Is the ambient temperature below 41°F(5°C)?
Is liquid food sealed?
Check if food put in the refrigerator is hot.
Did you open the door of the unit too
often or check if the door is sealed properly?
Check if the ambient temperature and humidity of the surrounding air are high.
Is there a gap in the door gasket?
Is the unit positioned in a firm and even place?
Are any unnecessary objects placed
in the back side of the unit?
Check if the Drip Tray is not firmly fixed.
Check if the cover of the compressor enclosure
in the lower front side is taken out.
Plug into the outlet.
Set the switch to ON.
Replace the fuse.
If the voltage is low, correct the wiring.
Place the unit about 4 inches (10 cm) from the wall.
Place the unit away from these heat sources.
Lower the ambient temperature.
Put in foods after they have cooled down.
Don't open the door too often and close
it firmly.
Set the control to Recommended position.
Place foods in the high-temperature section.
(front part)
Set the control to Recommended position.
Set the control to Warm position.
Seal liquid foods with wrap.
Put in foods after they have cooled down.
Don't open the door too often and close
it firmly.
Wipe moisture with a dry cloth. It will disappear in low temperature and humidity.
Fill up the gap.
Adjust the Leveling Screw, and position the
refrigerator in a firm place.
Remove the objects.
Fix the Drip Tray firmly in the original position.
Place the cover in its original position.
Door does not close well.
Ice and foods smell unpleasant.
Other possible problems:
Check if frost forms in the freezer.
Check the refrigeration system.
Check the Thermistor.
Check if the door gasket is dirty with an item like juice.
Is the refrigerator level?
Is there too much food in the refrigerator?
Check if the inside of the unit is dirty.
Are foods with a strong odor unwrapped?
The unit smells of plastic.
Not defrosting
The system is faulty.
The operation of the Thermistor is incorrect.
Clean the door gasket.
Position in the firm place and level the
Leveling Screw.
Make sure food stored in shelves does not prevent the door from closing.
Clean the inside of the unit.
Wrap foods that have a strong odor.
New products smell of plastic, but this
will go away after 1-2 weeks.
Check Components of the defrosting circuit.
Perform sealed system repair.
Replace the Thermistor.
- 17 -
6-5 REFRIGERATION CYCLE
YES
YES
Troubleshooting Chart
CAUSE
PARTIAL Freezer Low flowing sound of A little higher Refrigerant level is low due LEAKAGE compartment and Refrigerant is heard and than ambient to a leak.
LEAKAGE
COMPLETE Freezer Flowing sound of refrigerant Equal to ambient No discharging of Refrigerant. LEAKAGE compartment and is not heard and frost isn't temperature. Normal cooling is possible by
CLOGGED BY DUST
PARTIAL Freezer Flowing sound of refrigerant A little higher Normal discharging of the CLOG compartment and is heard and frost forms than ambient refrigerant.
WHOLE CLOG
MOISTURE Cooling operation Flowing sound of refrigerant Lower than Cooling operation restarts CLOG stops periodically. is not heard and frost melts. ambient when heating the inlet of the
COMPRESSION
COMP- Freezer and Low flowing sound of A little higher Low pressure at high side
DEFECTIVE
RESSION Refrigerator refrigerant is heard and ambient of compressor due to low
STATE OF
THE UNIT
Refrigerator don't frost forms in inlet only. temperature. Normal cooling is possible by cool normally. restoring the normal amount of
Refrigerator don't formed. restoring the normal amount of cool normally. refrigerant and repairing the leak.
Refrigerator don't in inlet only. temperature. The capillary tube is faulty. cool normally.
Freezer compartment and Refrigerator don't cool.
don't cool. frost forms in inlet only. temperature. refrigerant level.
STATE OF THE
EVAPORATOR
Flowing sound of refrigerant Equal to ambient Normal discharging of the is not heard and frost isn't temperature. Refrigerant. formed.
TEMPERATURE
OF THE
REMARKS
COMPRESSOR
refrigerant and repairing the leak.
temperature. capillary tube.
NO COMP- No compressing Flowing sound of refrigerant Equal to ambient No pressure in the high RESSION operation. is not heard and there is temperature. pressure part of the
no frost. compressor.
Leakage Detection
Observe the discharging point of the refrigerant, which may be in the oil discharging part of the compressor and in a hole
in the evaporator.
Check if compressor runs.
Frost formed normally
Moisture Clog
Faulty Compressor.
Check Compressor
Check if frost forms in Evaporator.
Normal amount
Clogged by dust. Gas leakage.
No frost or frost forms in inlet only
Observe the discharged amount of Refrigerant.
Inject refrigerant in compressor and check cooling operation.
Frost formed normally
Check if oil leaks.
None or too much
(Find the leak and repair it)
- 18 -
General Control of Refrigerating Cycle
NO. ITEMS UNIT STANDARDS PURPOSES REMARKS
Pipe and
1
piping system opening time
Welding
2
N
2 sealed
3
parts
Refrige-
4
ration Cycle
Evacuation time
Vacuum degree
Vacuum
Vacuum piping
Min.
Nitrogen pressure
Confirm N
2 leak
Min.
Torr
EA
EA
Pipe: within 1 hour. Comp: within 10 minutes. Drier: within 20 minutes.
Weld under Nitrogen atmosphere. (N
2 pressure:
0.1~0.2 kg/cm
2
)
Confirm the sound of pressure relief when removing the rubber cap. Sound: usable No sound: not usable
More than 40 minutes
Below 0.03 (ref)
High and low pressure sides are evacuated at the same time for models above 200 l.
Use R-134a manifold exclusively.
To protect moisture penetration.
To protect oxide scale formation.
To protect moisture penetration.
To remove moisture.
To protect mixing of mineral and ester oils.
The opening time should be reduced to a half of the standards during rain and rainy seasons (the penetration of water into the pipe is dangerous).
- Refer to repair note in each part.
- R-134a refrigerant is more susceptible to leaks than R-12 and requires more care during welding.
-
Do not apply force to pipes before and after welding to protect pipe from cracking.
- In case of evaporator parts, if it doesn't make sound when removing rubber cap, blow dry air or N
2 gas for more
than 1 min. and than use the parts.
Note: Only applicable to the model
equipped with reverse flow protect plate.
Vacuum efficiency can be improved by operating compressor during evacuation.
The rubber pipes for R-12 refrigerant will be melted when they are used for R-134a refrigerant (causes of leak.)
Refrigerant
5
weighing
Drier
6
replacement
Leak check
7
Pipe coupler
Outlet (Socket)
Plug
EA
EA
Use R-134a manifold exclusively.
R-134a manifold exclusively.
R-134a manifold exclusively.
Use R-134a exclusively. Weighing allowance: ±5g Note: Winter: -5g
Summer: +5g
- Use R-134a exclusively for R-134a refrigerator.
-
Replace drier whenever repairing refrigerator cycle piping.
- Do not use soapy water for check. It may be sucked into the pipe by a vacuum.
To protect R-12 refrigerant mixing.
To protect R-12 refrigerant mixing.
To protect R-12 refrigerant mixing.
Do not mix with R-12 refrigerant.
To remove the moisture from pipe inside.
Defect in refrigerant leak area.
- Do not weigh the refrigerant at too hot or too cold an area. (77°F [25°C] is adequate.)
- Make Copper charging canister (Device filling refrigerant) Socket: 2SV Plug: 2PV R-134a Note: Do not burn O-ring (bushing)
during welding.
- Check for an oil leak at the refrigerant leak area. Use an electronic leak detector if an oil leak is not found.
- The electronic leak detector is very sensitive to halogen gas in the air. It also can detect R-141b in urethane. Practice many times before using this type of detector to avoid false readings.
- 19 -
7. OPERATION PRINCIPLE AND REPAIR METHOD OF ICEMAKER
• Adjusts EJECTOR to Start Position with power on.
Power On
Start Position
Ice Making
Mode
Harvest
Mode
Park Position
Fill
Test Mode
• Waits until water becomes cold after starting the ice making operation.
• Runs MOTOR to drop ice from the tray the ICE BIN.
• Performs Ice Making Mode after supplying water by operating the SOLENOID in ICE VALVE.
• To operate LINE and SERVICE, press and hold the Fill Key for 3 seconds. The ice maker will run through 3 stages: Harvest Fill Icemaking.
• With the detect lever, checks if the ICE BIN is full.
7-1 OPERATION PRINCIPLE
7-1-1 Operation Principle of IceMaker
1. Turning the Icemaker stop switch off (O) stops the ice making function.
2. Setting the Icemaker switch to OFF and then turning it back on will reset the icemaker control.
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7-2 CONTROL METHOD ACCORDING TO FUNCTIONS
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
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 doesnt switch to water-supply mode, but restarts the ice­removing 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.)
<fig1. Ice removing process>
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