LG LM-2421C2L/A2L Service Manual Download Page 45

Page: 45 / 56

- 45 -

PCB Board Operation Check in Outdoor

Items

• Power Transformer

(Outdoor unit)
- Input Voltage
- Output Voltage

• IC01D(7812) Output

(Indoor/Outdoor unit)

• IC02D(7805) Output

(Indoor/Outdoor unit)

• IC01A(KIA7036, Reset IC)

X01(8MHz)

• Replace Trans

• Replace IC01D

• Replace IC02D

• Replace faulty parts

- About AC220V/240V±10% - Check the power voltage
- About AC14±3V

• DC +12V

• DC +5V

Content

Remedy

6. Outdoor unit does not operate at all.

7. Communication error

• The control data can be transmitted or received between indoor and outdoor unit with one signal cable.

• If the data be disturbed by any noise level, the unit will be operated incorrectly. In this case, the indoor unit

blinks the operation and operation LED on display and indoor fan, outdoor fan, COMP are not operated.

• The unit can be reoperated by On/Off control of Remocon.

Check Outdoor Unit

Turn off Main Power

• Check the electrical wiring diagram of outdoor side.
• Check the abnormal condition for the component of

Compressor/Outdoor Fan Motor/4-way.

• Check the “open” or “short” of connecting wires between indoor and

outdoor.

Summary of Contents for LM-2421C2L/A2L

Page 1: ...Multi Type Room Air Conditioner SERVICE MANUAL MODEL LM 2421C2L A2L LM 3022C3L A3L ...

Page 2: ...s 12 Display Function Self diagnosis Function 14 Installation 15 Operation 31 Disassembly of the parts Indoor Unit 32 2 way 3 way Valve 34 Cycle Troubleshooting Guide 38 Electronic Parts Troubleshooting Guide 40 Electronic Control Device 46 Schematic Diagram 47 Exploded View and Replacement Parts List 50 2 Contents ...

Page 3: ...operation Room temperature control Starting Current Control Time Delay Safety Control Indoor Fan Speed Control Intermittent operation of fan at low speed Soft Dry Operation Mode Used to set the time of stopping operation Off Timer Control Operation ON OFF Operation Mode Selection Fan Speed Selection Temperature Setting Airflow Direction Control The louver can be set at the desired position or swin...

Page 4: ...peration A or B unit A B unit Unit Indoor Outdoor Indoor Outdoor Indoor Outdoor Indoor Outdoor Indoor Outdoor Liquid Gas Item Cooling Capacity Btu h kcal h Moisture Removal h Power Source ø V Hz Air Circulation m3 min Noise Level Low dB A Input W Runnig Current A E E R Btu h w Motor Output W Dimensions W x H x D mm Net Weight kg Refrigerant R 22 g Airflow Direction Control Up Down Remocon Type Ser...

Page 5: ...r 888 x 287 x 170 Outdoor 870 x 655 x 320 Indoor 10 Outdoor 63 1 800 O L C D Wireless Liquid 1 4 6 35 Gas 1 2 12 7 O Operation A Unit B or C Unit A B or C B C A B C Unit Item Cooling Capacity Btu h kcal h Moisture Removal h Power Source ø V Hz Air Circulation m3 min Noise Level Low dB A Input W Runnig Current A E E R Btu h w Motor Output W Dimensions W x H x D mm Net Weight kg Refrigerant R 22 g A...

Page 6: ... Dimensions Installation plate A A ø70mm Center Center ø70mm Left rear piping Right rear piping A A D H W Tubing hole cover W mm 888 H mm 287 D mm 170 LM 2421C2L A2L LM 3022C3L A3L MODEL DIM 1 Indoor Unit ...

Page 7: ...s side 3 Way valve Liquid side 2 Way valve L7 L5 L6 2 Outdoor Unit 2 1 LM 2421C2L A2L W mm 870 H mm 655 D mm 320 L1 mm 370 L2 mm 25 L3 mm 630 L4 mm 25 L5 mm 546 L6 mm 160 L7 mm 160 L8 mm 64 L9 mm 76 5 L10 mm 50 LM 2421C2L LM 2421A2L MODEL DIM ...

Page 8: ...L9 Gas side 3 way valve Liquid side 2 way valve L10 L10 L10 L10 W mm 870 H mm 655 D mm 320 L1 mm 370 L2 mm 25 L3 mm 630 L4 mm 25 L5 mm 546 L6 mm 160 L7 mm 160 L8 mm 64 L9 mm 76 5 L10 mm 50 LM 3022C3L LM 3022A3L MODEL DIM 2 2 LM 3022C3L A3L ...

Page 9: ...COMP 3 WAY Valve ø6 35 ø12 7 ø12 7 ø6 35 HEAT EXCHANGER HEAT EXCHANGER A Unit B Unit Pipe Size Diameter inch Max piping length m Max piping elevation m Gas Liquid 1 2 1 4 10 15 5 7 ex Solenoid Valve Capillary Cooling 1 LM 2421C2L A2L ...

Page 10: ... WAY Valve ACCUMUIATOR ø6 35 ø12 7 ø12 7 ø12 7 ø6 35 ø6 35 HEAT EXCHANGER HEAT EXCHANGER A Unit B Unit C Unit Pipe Size Diameter inch Max piping length m Max piping elevation m Gas Liquid 1 2 1 4 10 15 5 7 ex Solenoid Valve Capillary Cooling ...

Page 11: ...CK 10P T BLOCK 1 L A UNIT B UNIT TO INDOOR UNIT OUTDOOOR WIRING DIAGRAM C UNIT MAIN POWER 1 L 1 L 2 N 2 N 3 3 3 2 N 2 N BK BK BK BK BK OR OR YL RELAY CAPA MOTOR COMP WH WH WH WH BL BL BL BL BL WH WH RD C B A CN COM CN TRANS TRANS FORMER MAIN P C B ASM CN TH C C S R F TERMINAL BLOCK 10P 1 L 2 N 2 N 1 L 3 1 L 2 N 3 A UNIT T BLOCK BL BL BK BK TRANS FORMER OR THERMISTOR YL OR BK BR WH CAPA BK MOTOR CO...

Page 12: ...y set according to the intake air temperature 26 C Intake Air Temp 25 C 24 C Intake Intake Air Temp 26 C Intake Air Temp 1 C 18 C Intake Intake Air Temp 24 C Intake Air Temp 0 5 C Intake Air Temp 18 C 18 C While in compressor off the indoor fan repeats low airflow speed and pause While the intake air temp is between compressor on temp and compressor off temp 10 min dehumidifica tion operation and ...

Page 13: ...e control position the forced operation is canceled and the appliance stops operating The forced operation is carried out in cooling mode with the setting temperature 22 C and the high speed of airflow While in forced operation the key input by the remote control has no effect and the buzzer sounds 10 times to indicate the forced operation Remote Control Operation Mode When the remote control is s...

Page 14: ...heck Communication line circuit check Outdoor suction temperature thermistor open short Outdoor pipe temperature thermistor open short Poor communication Error Indicator The function is to self diagnoisis airconditioner and express the troubles identifically if there is any trouble Error mark is ON OFF for the operation LED of evaporator body in the same manner as the following table If more than ...

Page 15: ...ined A place where noise prevention is taken into consideration Do not install the unit near the door way Ensure the spaces indicated by arrows from the wall ceiling fence or other obstacles 2 Outdoor unit If an awning is built over the unit to prevent direct sunlight or rain exposure be careful that heat radiation from the condenser is not restricted There should not be any animals or plants whic...

Page 16: ...e arrows marked on lower the left and the rght side of the Installation Plate The meeting point of the extended line is the center of the hole Drill the piping hole at either the right or the left and the hole should be slightly slant to the out door side Installation Plate marking off line Thread Weight Type A screw ø70mm ø70mm 5 7mm A A A A Indoor Outdoor Wall Left rear piping Right rear piping ...

Page 17: ...ipes Some refrgerant gas may leak when the flare nuts are removed from the indoor unit as some gas is charged to prevent the inside of the pipe from rusting Fit the copper pipe end into the Bar of flare tool about 0 0 5mm higher See illustration Flare the pipe ends 4 Tape the flaring portion to protect it from the dust or damages 90 Slanted Pipe cutter Rough Reamer Pipe Point down A Bar Copper pip...

Page 18: ...ain hose and drain pipe Don t connect the cable to the indoor unit Wrap the insulation material around the connect ing portion Glue up the connection portion of drain hose and drain pipe Installation plate Pull Pull Pipe Size Torque Liquid Side 1 4 1 8kg m Gas Side 1 2 5 5kg m Pull Press Indoor unit tubing Flare nut Pipings Spanner Torque wrench Plastic bands Insulation material Drain hose Drain p...

Page 19: ... drain pan inside the unit 7 Indoor unit installation Hook the indoor unit onto the upper portion of the installation plate Engage the two hooks of the rear top of the indoor unit with the upper edge of the installation plate Insure the hooks are properly seated on the installation plate by moving it in left and right Tape Loop Gas side piping Liquid side piping Drain hose Connecting cable Connect...

Page 20: ...tion 4 Insert the pipings and the connecting cable into the piping hole 5 Insert the connecting cable into the indoor unit Don t connect the cable to the indoor unit Make a small loop with the cable for easy con nection later 6 Tape the tubing drain hose and the connecting cable Tubing holder Drain hose To remove the holder press the bottom of the chassis near the holder upwards and the tab is cle...

Page 21: ... tighten the flare nut with fingers Finally tighten the flare nut with torque wrench until the wrench clicks Wrench tightening the flare nut with torque wrench ensure the direction for tightening fol lows the arrows on the wrench 9 Wrap the insulation material around the connecting portion CAUTION Take care to arrange the pipings drain hose and cables as the right upper picture for inserting it in...

Page 22: ...it installation Hook the indoor unit onto the upper portion of installation plate Engage the two hooks of the rear top of the indoor unit with the upper edge of the installation plate Ensure the hooks are properly seated on the installation plate by moving it in left and right Connecting cable Drain hose Press the lower left and right side of the unit against the Installation Plate until the hooks...

Page 23: ...ave an air gap contact separation of at least 3mm in each active phase conductors 3 The screw which fasten the wiring in the casing of electrical fittings are liable to come loose from vibrations to which the unit is subjected during the course of transportation Check them and make sure that they are all tightly fastened If they are loose it could give rise to burn out of the wires 4 Specification...

Page 24: ... the holder clamper 3 Refix the cover control to the original position with the screw 4 Use a recongnized circuit breaker between the power source and the unit A disconnection device to ade quately disconnect all supply lines must be fitted CAUTION ø8 5mm GN YL 20mm ø7 5mm GN YL 20mm The power cord connected to the outdoor unit should be complied with the following specifica tions Rubber insulatio...

Page 25: ...tion horizontally by finger pressure Remove the securing screws To remove the Grille pull lower the left and right side of the grille toward you slightly tilted and lift it straight upward 2 Check the drainage Pour a glass of water on the evaporator Ensure if water flows drain hose of indoor unit without any leakage 4 Checking the Drainage and Pipe forming ...

Page 26: ...lower the left and right side of the Grille and engage four tabs on the top inside edge of the chassis Press the Grille toward the chassis until it will be back into place Terminal on the OUTDOOR UNIT Terminal on the INDOOR UNIT Terminal on the INDOOR UNIT Terminal on the INDOOR UNIT A UNIT B UNIT C UNIT Power Cord 1 L 1 L 2 N 2 N 1 L 2 N 3 3 2 N 3 3 1 L 2 N 3 1 L 2 N 3 2 N 1 L 1 L 2 N 1 L 2 N 3 3...

Page 27: ...rom the ground Do not dip it into water and fix it on the wall to avoid swinging in the wind 2 Tape the Pipings drain hose and Connecting Cable from down to up 3 Form the pipings gathered by taping along the exterior wall and fix it onto the wall by saddle or equivalent 1 Tape the Pipings and Connectiong cable from down to up 2 Form the pipings gathered by taping along the exterior wall and the Tr...

Page 28: ...port nut and connect the gauge manifold and the vacuum pump to the service port by the charge hose 4 Vacuum the indoor unit and the connecting pipes until the pressure in them lowers to below 76cmHg 5 Disconnect the charge hose and fit the nut to the service port Tightening torque 1 8kg m 6 Remove the valve stem nuts and fully open the stems of the 2 way and 3 way valves with a hexagon wrench 7 Ti...

Page 29: ...This product has a preventive function of cable mis connection In case of mis connection in case that the cables between indoor and outdoor units have not been connected properly it gives a warning signal of LED flickering 3 minutes after starting operation Press the forced operation key more than 3 seconds CAUTION Don t turn on all the indoor units all at once when you check the connection status...

Page 30: ...mance 1 Measure the temperature of the intake and discharge air 2 Ensure the difference between the intake temperature and the discharge one is more than 8 C 1 Connection of power supply 1 Connect the power supply cord to the inde pendent power supply 2 Prepare the remote control Insert two batteries provided Remove the battery cover from the remote con troller Slide the cover according to the arr...

Page 31: ...down airflow direction OPERATION MODE SELECTION BUTTON Used to select the operation mode OFF TIMER BUTTON Used to set the time of stopping operation START STOP BUTTON Operation starts when this button is pressed and stops when the button is pressed again ROOM TEMPERATURE SETTING BUTTONS INDOOR FAN SPEED SELEC TION BUTTON 7 6 5 4 3 2 1 Remote Control Name and Function Remote Control TEMP TIME OFF h...

Page 32: ...essure Remove the securing screws To remove the Grille pull the lower left and right side of the grille toward you slightly tilted and lift it straight upward 1 To remove the sensor housing connect earth conductor step motor conductor with sensor holder Motor Evaporator P C B 32 Disassembly of the parts Indoor unit Screw 3EA Motor Conductor Step Motor Conductor Display PCB Conductor Earth Conducto...

Page 33: ...rator and the holder eva Unhook the tab on the right inside of the chas sis at the same time slightly pull the evapora tor toward you until the tab is clear of the slot 5 To remove the Cross Flow Fan Loosen the screw securing the cross flow fan to the fan motor do not remove Lift up the right side of the cross flow fan and the fan motor separate the fan motor from the cross flow fan Remove the lef...

Page 34: ...pen Open Transfering clockwise counter clockwise connected manifold gauge Evacuation Open Open Open Servicing with vacuum pump Gas charging Open Open Open Servicing with charging cylinder Pressure check Open Open Open Servicing with charging cylinder Gas releasing Open Open Open Servicing with charging cylinder 3 2 1 4 5 6 To outdoor unit Hexagonal wrench 4mm Open position Closed position To pipin...

Page 35: ...n the gauge slightly to air purge from the hose 5 Set the liquid side valve to the closed position 6 Operate the air conditioner at the cooling cycle and stop it when the gauge indicates 1kg cm2 g 7 Immediately set the gas side valve to the closed position Do this quickly so that the gauge ends up indi cating 1kg cm2 g 8 Disconnect the charge set and mount the liquid side and gas side valve caps a...

Page 36: ...g vacuum of 4 mmHg or less 5 Close the Low handle of the gauge turn off the vacuum pump and confirm that the gauge nee dle does not move approximately 5 minutes after turning off the vacuum pump 6 Disconnect the charge hose from the vacuum pump Vacuum pump oil If the vacuum pump oil becomes dirty or deplet ed replenish as needed 7 Mount the valve caps and the service port caps 8 Apply steps from 1...

Page 37: ...system with liquid refrigerant If the system can not be charged with the speci fied amount of refrigerant it can be charged with a little at a time approximately 150g each time while operating the air conditioner in the cooling cycle however one time is not suffi cient wait approximately 1 minute and then repeat the procedure pumping down pin 4 Immediately disconnect the charge hose from the gas s...

Page 38: ... is usually 4 5 6 0 kg cm2 G at normal condition 2 The temperature can be measured by attaching the thermometer to the low pressure tubing and wrap it with putty 38 Cycle Troubleshooting Guide Temp difference approx 0 C Current less than 80 of rated current Temp difference approx 8 C Current less than 80 of rated current Temp difference less than 8 C Current over the rated current Temp difference ...

Page 39: ... from all three indoor unit Compressor is operating normally Outdoor unit is clogged by extraneous substances Cool air from indoor unit Remove it and turn off Main Power Source Turn on Main Power Operating after 3 minutes Check refrigerant pressure Suction pressure is usually 4 5 6 0kg cm2 at normal condition Recharge refrigerant ...

Page 40: ...ge Varistor ZNR01J Check the connection housing for contacting Connector related to CN POWER Display PWB Ass y Check Check each load Indoor Outdoor Fan Motor Compressor Stepping Motor etc and contacting condition of related connector PCB Board Operation Check Items Power Transformer Outdoor unit Input Voltage Output Voltage IC01D 7812 Output Indoor Outdoor unit IC02D 7805 Output Indoor Outdoor uni...

Page 41: ... not controlled by the remote controller When operated in the Sleeping Mode the wind speed is set to the low speed by force Check DISP PWB Ass y Voltage between CN DISP1 DC 5V When the detect switch double key inside the remote controller door is fault it is impossible to operate temperature regulating and wind speed selecting Check the connecting circuit between the remote con troller MICOM No R1...

Page 42: ...for indoor temperature and connector are in bad connection or are not engaged Compressor Outdoor Fan is stopped Check the related circuit of R02H 12 1K R01H 1 0K R04H 6 2K R03H 1 0K Indoor unit Check the indoor temperature sensor is disconnected or not About 10kΩ at 25 C Check Outdoor Unit Check Relay RY COMP for driving compressor When the power About AC220V 240V is applied to the connecting wire...

Page 43: ...ON Main Power Check the related circuit of indoor Fan Motor The pin of Micom and the part for driving SSR Check the pattern Check the SSR SSR Open Indoor Fan Motor never operate SSR short Indoor Fan Motor always operates in case of ON or OFF 4 When indoor Fan does not operate The voltage of PIN NO 1 blue and 3 yellow of CN FAN or CN MOTOR About AC 180V over About AC 50V over SSR is not damaged SSR...

Page 44: ...ndition of CN U D Connector Check the soldering condition on PWB of CN U D Connector If there are no problems after above checks Confirm the assembly conditions that are catching and interfering parts in the rotation radial of the Vertical Louver 5 When Vertical Louver does not operate Check the operating circuit of the Vertical Louver Confirm that there is DC 12V between pin RED of CN U D and GND...

Page 45: ... error The control data can be transmitted or received between indoor and outdoor unit with one signal cable If the data be disturbed by any noise level the unit will be operated incorrectly In this case the indoor unit blinks the operation and operation LED on display and indoor fan outdoor fan COMP are not operated The unit can be reoperated by On Off control of Remocon Check Outdoor Unit Turn o...

Page 46: ...1 Indoor LM 2421C2L A2L LM 3022C3L A3L MAIN P C B ASSY 2 Outdoor LM 2421C2L A2L LM 3022C3L A3L MAIN P C B ASSY 46 Electronic Control Device 3 DISPLAY P C B ASSY ...

Page 47: ... 47 Schematic Diagram 1 Indoor LM 2421C2L A2L LM 3022C3L A3L ...

Page 48: ... 48 2 Outdoor 2 1 LM 2421C2L A2L ...

Page 49: ... 49 2 2 LM 3022C3L A3L ...

Page 50: ... 50 733010 131410 342800 135311 135312 267110 135314 152302 159901 352150 35211B 354212 346810 W0CZZ 268714 249951 359011 Exploded View Replacement Parts List 1 Indoor Unit LM 2421C2L A2L LM 3022C3L A3L ...

Page 51: ...ONTROL BOX ASSY INDOOR R 263230 6323AQ2333A THERMISTOR ASSY R 267110 6711A20016T REMOTE CONTROLLER ASSY R 268712 6871A30009E PWB PCB ASSY DISPLAY R 268714 6871A20075Y PWB PCB ASSY MAIN R 342800 3H02821B BEARING R 346810 4681A20003R MOTOR ASSY INDOOR R 35211B 2H02449J TUBE ASSY TUBING R 352150 5251AR2575A HOSE ASSY DRAIN R 354212 5421A20031S EVAPORATOR ASSY FINAL R 359011 5901AR6141B FAN ASSY CROSS...

Page 52: ... 52 2 Outdoor Unit LM 2421C2L A2L 554031 649950 546810 546810 559010 435512 437210 430411 447910 554160 263230 W0CZZ 552203 552203 550140 437212 435511 ...

Page 53: ...TDOOR R 546810 4681A20008D 4681A20008D MOTOR ASSY A C R 550140 4H00637A 4H00637A ISOLATOR COMP R 552101 5211A10088A 5211A10088A TUBE ASSY CAPILLARY R 552203 2H01890D 2H01890D VALVE SERVICE R 552203 2H02479D 2H02479D VALVE SERVICE R 554031 5403A20022D 5403A20022M CONDENSER ASSY BENT R 554160 5416AR1581B 5416AR1581B COMPRESSOR R 559010 1A00195B 1A00195B FAN ASSY PROPELLER R 649950 4995A20044J 4995A2...

Page 54: ... 54 LM 3022C3L A3L 554031 649950 546810 546810 559010 435512 437210 430411 447910 554160 263230 268716 W0CZZ 552203 552203 550140 437212 435511 ...

Page 55: ...10 4791A30004A 4791A30004A BARRIER ASSY OUTDOOR R 546810 4681A20008D 4681A20008D MOTOR ASSY A C R 546810 4961A20002C 4961A20002C MOUNT ASSY MOTOR OUTDOOR R 552203 2H01890F 2H01890F VALVE SERVICE R 552203 2H02479L 2H02479L VALVE SERVICE R 554031 5403A20022B 5403A20047Z CONDENSER ASSY BENT R 554160 5417A10001C 5417A10001C COMPRESSOR ASSY FINAL R 559010 1A00195B 1A00195B FAN ASSY PROPELLER R 649950 4...

Page 56: ...P No 3828A20023G January 2002 Printed in Korea ...

Search results

Summary of Contents for LM-2421C2L/A2L

Reviews:

Related manuals for LM-2421C2L/A2L

Brands by name

Popular brands

LG LM-2421C2L/A2L, Service Manual

Search results

Summary of Contents for LM-2421C2L/A2L

Reviews:

Related manuals for LM-2421C2L/A2L

Brands by name

Popular brands