background image

LG 

Room

Air Conditioner

SERVICE MANUAL

LG

MODELS: LWC121CGMK0

LWC143CGMK0
LWC143CSMK0
LWC243NSAB1
LWC243NSMM1

CAUTION

website http://www.lgservice.com

• BEFORE SERVICING THE UNIT, READ THE SAFETY 

PRECAUTIONS IN THIS MANUAL.

• ONLY FOR AUTHORIZED SERVICE PERSONNEL.

    

Summary of Contents for LWC121CGMK0

Page 1: ...RVICE MANUAL LG MODELS LWC121CGMK0 LWC143CGMK0 LWC143CSMK0 LWC243NSAB1 LWC243NSMM1 CAUTION website http www lgservice com BEFORE SERVICING THE UNIT READ THE SAFETY PRECAUTIONS IN THIS MANUAL ONLY FOR AUTHORIZED SERVICE PERSONNEL ...

Page 2: ...12 How to Install Installation kit included models 13 When Using Installation Kits 13 Suggested Tool Requirements 14 Operation 17 Features 17 Function of Controls 17 Disassembly 20 Mechanical Parts 20 Air Handling Parts 21 Electrical Parts 22 Refrigerating Parts 24 Schematic Diagram 27 Electronic Control Device 27 Wiring Diagram 28 Components Location 29 Troubleshooting Guide 30 Piping System 30 T...

Page 3: ...dicates the possibility of death or serious injury This symbol indicates the possibility of injury or damage to property only WARNING Installation Always install the expansion panel s No installation may cause fire and electric shock acci dent Do not place the power cord near a heater It may cause fire and electric shock Do not use the power cord near flammable gas or combustibles such as gasoline...

Page 4: ...r fire Do not modify power cord length It will cause electric shock or fire due to heat generation Do not share the outlet with other appliances It will cause electric shock or fire due to heat generation Always plug into a grounded outlet No grounding may cause electric shock See Installation Manual Unplug the unit if strange sounds odors or smoke come from it Otherwise it may cause fire and elec...

Page 5: ...the unit when removing the filter They are sharp and may cause injury Do not block the inlet or out let It may cause failure of appliance or accident Ensure that the outer case is not damaged by age or wear If leaving appliance damaged there is concern of damage due to the falling of product Be cautious not to touch the sharp edges when installing It may cause injury Hold the plug by the head when...

Page 6: ... during operation it may cause injury Do not put a pet or house plant where it will be exposed to direct air flow This could injure the pet or plant Do not use this appliance for special purposes such as pets foods precision machinery or objects of art It is an air conditioner not a preci sion refrigeration system Always insert the filter securely Clean it every two weeks Operation without filters...

Page 7: ...6 Model Dimension 12K 14K MODELS D mm inch 560 22 5 16 555 21 6 7 Look Dimension G P E N Outside Dimensions This symbol alerts you to the risk of electric shock This symbol alerts you to hazards that could cause harm to the air conditioner This symbol indicates special notes NOTICE Symbols Used in this Manual ...

Page 8: ...8 Room Air Conditioner D W H W mm inch 660 26 H mm inch 428 16 27 32 D mm inch 675 26 9 18 Model Dimension 24K Btu Dimensions ...

Page 9: ...CONTROL CONSTRUCTION PROTECTOR COMPRESSOR FAN MOTOR POWER CORD DRAIN SYSTEM NET WEIGHT lbs kg OUTSIDE DIMENSION inch W x H x D mm 1Ø 115V 60Hz 1Ø 220V 60Hz 12 000 14 000 1 220 1 400 11 6 2 9 8 10 26 7 DB 19 4 WB 35 DB 23 9 WB 355g 12 5oz 670g 23 6oz 2 ROW 16STACKS 2 ROW 13STACKS 2 ROW 18STACKS 2 ROW 14STACKS TURBO PROPELLER TYPE FAN WITH SLINGER RING 3 3 6 POLES REMOTE CONTROLLER THERMISTOR VERTIC...

Page 10: ...ONTROL AIR DIRECTION CONTROL CONSTRUCTION PROTECTOR COMPRESSOR FAN MOTOR POWER CORD DRAIN SYSTEM NET WEIGHT lbs kg OUTSIDE DIMENSION inch W x H x D mm 1Ø 220V 60Hz 24 000 2 820 12 9 8 5 26 7 DB 19 4 WB 35 DB 23 9 WB 985g 34 8oz 3 ROW 15STACKS 2 ROW 19STACKS TURBO PROPELLER TYPE FAN WITH SLINGER RING 2 3 3 3 6 POLES ROTARY SWITCH REMOTE CONTROLLER THERMISTOR THERMISTOR VERTICAL LOUVER RIGHT LEFT HO...

Page 11: ...ints when the installation is finished 1 Grounding wire Green or Green and Yellow is provided in the power cord The green wire must be grounded 2 Connect to a single outlet 15A circuit or 20A circuit for Electric Heater Model 3 To avoid vibration or noise make sure the air conditioner is installed securely 4 Avoid placing furniture or draperies in front of the air inlet and outlet In humid weather...

Page 12: ...the cabinet 3 Remove EPS Material 4 Slide the unit into the cabinet CAUTION For security pur pose reinstall screw at cabi net s sides 5 Attach the front grille to the cabinet by inserting the tabs on the grille into the tabs on the fornt of the cabinet Push the grille in until it snaps into place 6 Lift the inlet grille and secure it with a screw through the front grille Shipping screws EPS Materi...

Page 13: ...B 1 WINDOW WIDTH A HEIGHT B 2 GASKET 3 WALL 4 DETAILS 5 1 x 30 ROUND HEAD WOOD SCREWS A B C D E F H I 625mm 392mm 280mm 30mm 0 25mm OVER 420mm 5 10mm 5 5mm 245 8 157 16 111 32 11 16 0 1 OVER 1617 32 3 16 3 8 3 16 3 16 27 to 39 16 min Stool Interior wall 235 8 min Without frame curtain Offset 1 2 to 11 4 Sill Exterior 1 2 3 4 8 11 12 9 7 6 5 10 Top retainer bar is in the product package NO NAME OF ...

Page 14: ...pe A screws 7 Insert the frame guides into the bottom of the cabinet 8 Insert the Frame Curtain into the upper guide and frame guides 9 Fasten the curtains to the unit with 4 Type A screws at the both sides Cabinet Installation 1 Open the window Mark a line on center of the win dow stool or desired air conditioner location Carefully place the cabinet on the window stool and align the center mark o...

Page 15: ...roken easily 5 Attach the sill support to the cabinet track hole in relation to the selected position using 2 Type A screws in each support See Figure 5 6 The cabinet should be installed with a very slight tilt about 1 2 downward toward the outside See Figure 6 Adjust the bolt and the nut of Sill Support for bal ancing the cabinet 7 Attach the cabinet to the window stool by driving the screws Type...

Page 16: ...nd insert between the upper and lower window sash See Fig 9 12 Attach the window Locking Bracket with a type C screw See Fig 10 13 Attach the front grille to the cabinet by inserting the tabs on the grille into the tabs on the front of the cab inet Push the grille in until it snaps into place See Fig 11 14 Lift the inlet grille and secure it with a type A screw through the front grille See Fig 12 ...

Page 17: ...ocations Function of Controls CLOSE VENT OPEN Operation Off Turns air conditioner off Med Fan Med speed fan operation without cooling Low Fan Low speed fan operation without cooling High Cool Cooling with high speed fan operation Med Cool Cooling with med speed fan operation Low Cool Cooling with low speed fan operation For Normal Cooling 1 Turn the Operation Knob to the High Cool from the Low Coo...

Page 18: ...n it will toggle COOL FAN and DRY 3 ON OFF TIMER BUTTON Everytime you push this button timer is set as follows 1Hour 2Hours 3Hours 4Hours 5Hours 6Hours 7Hours 8Hours 9Hours 10Hours 11Hours 12Hours Cancel 4 FAN SPEED SELECTOR Everytime you push this button it is set as follows Hi F3 Low F1 Med F2 Hi F3 5 ROOM TEMPERATURE SETTING BUTTON This button can automatically control the temperature of the ro...

Page 19: ...ops when you press the button again 3 ROOM TEMPERATURE SETTING BUTTON Control the room temperature within a range of 16 C to 30 C 4 FAN SPEED SELECTOR Select the fan speed in three steps High F3 Low F1 Med F2 High F3 5 OPERATION MODE SELECTION BUTTON Select Cooling Fan or Dehumidification mode with this button 6 ON OFF TIMER BUTTON Set the time of starting and stopping operation The timer is set b...

Page 20: ... forward See Figure 15 4 Remove the cabinet 5 Re install the component by referring to the removal procedure above 3 Control Box 1 Remove the front grille Refer to section 1 2 Remove the cabinet Refer to section 2 3 Remove the 2 screws which fasten the control box cover 4 Remove two housings which connect compressor wire and motor wire in the control box 5 Discharge the capacitor by placing a 20 0...

Page 21: ...er See Figure 18 at Electric Heater Model 11 Remove the Heater cover See Figure 18 at Electric Heater Model 12 Pull out the hook of orifice by pushing the tabs and remove it See Figure 19 13 Remove the clamp with a hand plier that secures the blower 14 Remove the blower 15 Remove the 4 screws which fasten the air guide to the barrier 16 Move the air guide backward pulling out from the base pan 17 ...

Page 22: ...e removal procedure above 8 Compressor 1 Remove the cabinet Refer to section 2 2 Discharge the refrigerant system using a FreonTM Recovery System If there is no valve to attach the recovery sys tem install one such as a watco a 1 before venting the FreonTM Leave the valve in place after servicing the system 3 Remove the overload protector Refer to sec tion 7 4 After purging the unit completely unb...

Page 23: ...bove removal procedure above Use only one ground marked hole for ground connection 8 If the supply cord of this appliance is damaged it must be replaced by the special cord The special cord means the cord that has the same specification marked on the supply cord attached at the unit 11 Thermostat 1 Remove the control box Refer to section 3 2 Open the control box Refer to section 9 3 Remove the 2 s...

Page 24: ... WATCO A 1 before vent ing the FreonTM Leave the valve in place after servicing the system 14 Condenser 1 Remove the cabinet Refer to section 2 2 Remove the 4 screws which fasten the brace Refer to section 4 3 Remove the 5 screws which fasten the con denser and shroud 4 After discharging the refrigerant completely unbraze the interconnecting tube at the con denser connections 5 Remove the condense...

Page 25: ... vacuum pump and place it on the charging cylinder See figure 29B Open valve C Discharge the line at the manifold connection 5 The system is now ready for final charging 6 Recharge as follows 1 Refrigeration cycle systems are charged from the High side If the total charge cannot be put in the High side the balance will be put in the suction line through the access valve which you installed as the ...

Page 26: ...of making a vapor proof seal Leak detector Tubing cutter Hand Tools to remove components Service valve A COMPOUND GAUGE EVAPORATOR LOW PRESSURE SIDE COMPRESSOR CAPILLARY TUBE CONDENSER HIGH PRESSURE SIDE SEE INSETS BELOW MANIFOLD GAUGE B Figure 31A Pulling Vacuum Figure 31B Charging A B EXTERNAL VACUUM PUMP A CHARGING CYLINDER LOW HI B C ...

Page 27: ...QQQQQ QQQQQQQQQQQQQQQQQQQQ QQQQQQQQQQQQQQQQQQQQ QQQQQQQQQQQ QQQQQQQQQQQQQQQQQQQQ QQQQQQQQQQQQQQQQQQQQ QQQQQQQQQQQQ QQQQQQQQQQQQQQQQQQQQ QQQQQQQQQQQQQQQQQQQQ QQQQQQQQQQQQQ QQQQQQQQQQQQQQQQQQQQ QQQQQQQQQQQQQQQQQQQQ QQQQQQQQQQQQQ QQQQQQQQQQQQQQQQQQQQ QQQQQQQQQQQQQQQQQQQQ QQQQQQQQQQQQQ QQQQQQQQQQQQQQQQQQQQ QQQQQQQQQQQQQQQQQQQQ QQQQQQQQQQQQQ QQQQQQQQQQQQQQQQQQQQ QQQQQQQQQQQQQQQQQQQQ QQQQQQQQQQQQQ QQQQQ...

Page 28: ...WORK CN SYNC CN DISP DISPLAY P W B ASM RY SYNC 250V T2A 115V T2A TRANS FORMER ZNR RY COMP MAIN P W B ASM BK BK BR BR RD BL BL OLP RD MOTOR CAPACITOR F R S COMP C C H 3854AR2330P WIRING DIAGRAM RY MID FUSE RD BK PTC 4 3 Mechanical Model LWC243NSAB1 Micom Model LWC121CGMK0 LWC143CGMK0 LWC143CSMK0 LWC243NSMM1 1 3 4 7 2 6 5 WIRING DIACRAM ROCKER SWITCH WH WH SYNC M POWER INPUT WH BL BK BR Ribbed Plain...

Page 29: ...Service Manual 29 Schematic Diagram Components Location Main P C B Assembly Display P C B Assembly ...

Page 30: ...e cooling cycle MOTOR COMPRESSOR OIL LIQUID REFRIGERANT CAPILLARY TUBE OUTSIDE COOLING AIR FOR REFRIGERANT PASS THROUGH SUCTION LINE COOL LOW PRESSURE VAPOR COOLED AIR COMPLETE LIQUID BOIL OFF POINT LIQUID PRESSURE DROP ROOM AIR HEAT LOAD VAPOR INLET HOT DISCHARGED AIR LIQUID OUTLET HIGH PRESSURE VAPOR LIQUID REFRIGERANT LOW PRESSURE VAPOR ROOM AIR CONITIONER EVAPORATOR COILS CONDENSER COILS CYCLE...

Page 31: ... operation Check gas leakage Repair gas leak Replacement of unit if the unit is beyond repair Satisfactory operation with temperature difference of inlet outlet air 44 50 F 7 10 C Check heat load increase Clean condenser Not on separate circuit Check inside gas pressure Adjusting of refrigerant charged Malfunction of compressor Replacement of compressor Check cold air circulation for smooth flow D...

Page 32: ...rregular motor insulation Replacement of fan motor Regular but fails to start Replacement of compressor locking of rotor metal Improper thermostat setting Loose terminal connection Improper wiring Irregular motor resistance Irregular motor insulation Replacement of compressor Motor damaged Drop of power voltage Capacitor check Replacement Compressor only fails to start Defect of compressor capacit...

Page 33: ... attention to any change from high speed to low speed If the speed does not change replace the motor If cracked out of balance or partially missing replace it If cracked out of balance or partially missing replace it Tighten it If knocking sounds continue when running or loose replace the motor If the motor hums or noise appears to be internal while running replace motor Check voltage If not withi...

Page 34: ...nspect the interior surface of the condenser if restricted clean carefully with a vacuum cleaner do not damage fins or brush Clean the interior base before reassembling If condenser fins are closed over a large area on the coil surface head pressures will increase causing the compressor to overload Straighten the fins or replace the coil Test capacitor Check the terminals If loose repair or replac...

Page 35: ...Service Manual 35 Exploded View Exploded View 147582 269310 266003 W0CZZ 135500 264110 137215 266002 249950 149410 237200 552101 Indoor Unit 12K 14K MODELS ...

Page 36: ...010 W48602 554031 349600 346811 149980 550140 130410 147582 W48602 349480 152302 135312 249950 554160 135313 147581 2 147581 1 137215 266002 269310 W0CZZ 266003 135500 264110 146812 354210 149410 359012 349001 W0CZZ 146812 135500 135510 263230 261704 268712 237200 238310 268714 264110 249950 352390 MODEL 24K MODELS Exploded View ...

Page 37: ...0188C 6871A20188J 6871A20188F R 346811 MOTOR ASSEMBLY SINGLE 4681A20009P 4681A20009P 4681A20073B R 349001 DAMPER VENTILATION 4900AR7024A 4900AR7024A 4900AR7024B R 349480 ORIFICE 4948AR7034A 4948AR7034A 4948A10005A R 349600 MOUNT MOTOR 4960AR6165A 4960AR6165A 4960A20005A R 352113 TUBE ASSY DISCHARGE SINGLE 5211A20217A 5211A20217A 5211A20644A R 352380 AIR GUIDE 5238AR1499A 5238AR1499A R 352390 AIR G...

Page 38: ...NGLE 4995A20286Q 4995A20325B R 238310 ESCUTCHEON 3831A20032B R 237200 PANEL CONTROL 3720AR6163A R 152302 FILTER ASSY A C 5231AR6159A 5231AR6159A R 149980 SHROUD 4998AR1602A 4998AR1602A R 148000 BRACE 4800AR7271A 4800AR7271A R 147582 LOUVER VERTICAL 4758AR6157A 4758AR6157A R 146812 MOTOR ASSEMBLY SYNC 2H01102A 2H01102A R 137215 PANEL CONTROL 3720AR6163A 3721A10011L R 135500 COVER TERMINAL 3550U L00...

Page 39: ...Service Manual 39 Memo ...

Page 40: ...P No 3828A30032P July 2004 Printed in Korea ...

Reviews: