Room Air Conditioner SERVICE MANUAL MODELS: AS-W096ERH0 AS-W096EBH0 AS-W096EVH0 AS-W126ERH0 AS-W126EBH0 AS-W126EVH0 CAUTION • BEFORE SERVICING THE UNIT, READ THE SAFETY PRECAUTIONS IN THIS MANUAL. • ONLY FOR AUTHORIZED SERVICE PERSONNEL.
Air Conditioner Service Manual TABLE OF CONTENTS LG Model Name..........................3 Safety Precautions ...........................5 Dimensions .............................10 Installation............................12 Flaring work and connection of piping..................14 Connecting the cable between indoor unit and outdoor unit.............19 Checking the drainage and forming the pipings .................21 Air purging ............................22 Test running ............................24...
LG Model Name LG Model Name 2003 Code Type Code of Model Meaning Producing Center, L: Chang-won R22 N: India Refrigerant A: Chang-won R410A Z: Brazil C: Chang-won R407C D: Indonesia T: China M: Mexico K: Turkey R22 V: Vietnam...
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LG Model Name 2004~ Code Type Code of Model Meaning Chang_won R22 Producing Center, N India Chang_won R410A Z Brazil Refrigerant Chang_won R407C D Indonesia China X Mexico Turkey R22 V Vietnam Turkey R410A S Out sourcing Thailand Product Type...
Dimensions Dimensions Symbols Used in this Manual This symbol alerts you to the risk of electric shock. This symbol alerts you to hazards that could cause harm to the air conditioner. NOTICE This symbol indicates special notes. Indoor Unit Installation plate Model 9k, 12k Btu Series Dimension...
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Dimensions Outdoor Unit Gas side (3-way valve) Liquid side (2-way valve) MODEL 9k, 12k Btu Series unit Service Manual 11...
Installation Installation Selection of the Best Location Indoor unit Rooftop Installations: • Do not have any heat or steam near the unit. • If the outdoor unit is installed on a roof structure, be sure to level the unit. Ensure the roof structure and •...
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Installation How to Fix Installation Plate Drill a Hole in the Wall The wall you select should be strong and solid • Drill the piping hole with a ø70mm hole core drill. enough to prevent vibration Drill the piping hole at either the right or the left with the hole slightly slanted to the outdoor side.
Flaring work and connection of piping Flaring work and connection of piping Flaring work • Carry out flaring work using flaring tool as shown below. Outside diameter Flaring work inch Main cause for refrigerant leakage is due to defect in the Ø6.35 0~0.5 flaring work.
Flaring work and connection of piping Connecting the pipings to the indoor unit and For right rear piping drain hose to drain pipe. Route the indoor tubing and the drain hose in the direction of • Align the center of the pipes and sufficiently tighten rear right.
Flaring work and connection of piping • Bundle the piping and drain hose together by wrapping Connecting the pipings to the indoor unit and them with vinyl tape for enough to cover where they fit into the drain hose to drain pipe. the rear piping housing section.
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Flaring work and connection of piping • Wrap the area which accommodates the rear piping hous- Indoor unit installation ing section with vinyl tape. • Remove the spacer. Indoor Connection • Ensure that the hooks are properly seated on the installa- unit piping pipe tion plate by moving it left and right.
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Flaring work and connection of piping Connection of the pipes-Outdoor • Bad case Align the center of the pipings and sufficiently • Following bending type from right to left could cause tighten the flare nut by hand. problem of pipe damage. Finally, tighten the flare nut with torque wrench until the wrench clicks.
Connecting the cable between indoor unit and outdoor unit Connecting the cable between indoor unit and outdoor unit Connect the cable to the Indoor unit. Connect the cable to the indoor unit by connecting the wires to the terminals on the control board individually according to the outdoor unit connection.
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Connecting the cable between indoor unit and outdoor unit Connect the cable to the outdoor unit Outdoor Unit Remove the control cover from the unit by Terminal block loosening the screw. Connect the wires to the terminals on the con- Over 5mm trol board individually.
Checking the drainage and forming the pipings Checking the drainage and forming the pipings Checking the drainage Form the piping To remove the front panel from the indoor unit. Form the piping by wrapping the connecting portion of the indoor unit with insulation mate- •...
Air purging Air Purging Air purging • Do a leak test of all joints of the tubing(both indoor and out- door) and both gas and liquid side service valves. Air and moisture remaining in the refrigerant system have Bubbles indicate a leak. Be sure to wipe off the soap with a undesirable effects as indicated below.
Air purging Soap water method (1) Remove the caps from the 2-way and 3-way valves. Gas side (2) Remove the service-port cap from the 3-way valve. (3) To open the 2-way valve turn the valve stem counter- clockwise approximately 90°, wait for about 2~3 sec, and close it.
Test running Test Running 1. Check that all tubing and wiring have been properly con- NOTE: If the actual pressure is higher than shown, the system is nected. most likely over-charged, and charge should be removed. If the actual pressure are lower than shown, the system is 2.
Functions Functions Indoor Unit Cooling Mode Operation Healty dehumidification Mode Operation Heating Mode Operation Jet Cool Mode Operation Jet Heat Mode Operation Energy Saving Cooling Mode Operation Operation ON/OFF by Remote controller Sensing the Room Temperature • Room temperature sensor. (Thermistor) •...
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Functions Sleep Mode Auto Control • The fan is switched to low(Cooling), low(Heating) speed. • The unit will be stopped after 1, 2, 3, 4, 5, 6, 7 hours. Natural Air Control by CHAOS Logic • The fan is switched to intermittent or irregular operation •...
Functions Outdoor Unit Power Relay Control • If power is on, it will operate to chage capacitor on controller and power relay will operate after about 2~5sec. Active Power Filter Control(PSC) • The active power filter is designed to correct power factor(cos θ) and to regulate DC link voltage. •...
Operation Operation Function of Controls • DISPLAY 1) C/O Model Operation Indicator • ON while in appliance operation, OFF while in appliance pause. • Flashing while in disconnection or short in Thermistor. (3 sec off / 0.5 sec on) Timer Indicator •...
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Step 4 Step 5(Fc) Step 6 Step 7 AS-W096ERH0 / EBH0 / EVH0 AS-W126ERH0 / EBH0 / EVH0 Healthy Dehumidification mode operation • When the dehumidification operation is set by the remote controller the intake air temperature is detected and the setting temp.
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Step 4 Step 5(Fc) Step 6 Step 7 AS-W096ERH0 / EBH0 / EVH0 AS-W126ERH0 / EBH0 / EVH0 Jet cool mode operation • While in heating mode or Fuzzy operation, the Jet Cool key cannot be input. When it is input while in the other mode operation(cooling, dehumidification, ventilation), the Jet Cool mode is operated.
Operation Jet heat mode operation • While in cooling mode or Fuzzy operation, the Jet Heat key cannot be input. When it is input while in the Heating mode operation (dehumidification), the Jet Heat mode is operated. • In the Jet Heat mode, the indoor fan is operated super-high speed for 60 min. at Heating mode operation. •...
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Operation Sleep timer operation • When the sleep time is reached after [1,2,3,4,5,6,7hr] is input by the remote control during the operation, the operation of the appliance stops. • When the appliance is on pause, the sleep timer mode cannot be input. 1.
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Operation Auto restarting operation • When the power is restarted after a sudden power failure while in appliance operation, the mode before the power failure is kept on the memory and the appliance automatically operates in the mode on the memory. •...
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• If CT2 occurs 5 times within 1hour, the appliance turn off and display ERROR CODE 7. I1:Current of operating frequency down Control table I2: Current of compressor cut off Outdoor temp ≥ 38°C Model Outdoor temp < 38°C Cooling Heating Cooling Heating 1 AS-W096ERH0/BH0/VH0 7.0A 8.5A 7.5A 9.0A 10.0A 2 AS-W126ERH0/BH0/VH0 7.0A 8.5A 7.5A 9.0A 10.0A...
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∆T = (T off - T on) Heat Sink Temp. MODEL T on T off T1 = T on + ∆T T2 = T on + 2 * ∆T T off °C AS-W096ERH0/BH0/VH0 AS-W126ERH0/BH0/VH0 T2 °C T1 °C T on °C COMP Free Fc-1...
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Operation Defrosting control • While in heating mode operation in order to protect the evaporator pipe of the outdoor unit from freezing, reversed to cooling cycle to defrost the evaporator pipe of the outdoor unit. • Defrosting control is available 40 minutes later since heating cycle started and the difference of the pipe tem- perature of outdoor unit reaches above option 1.
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Operation Auto Cleaning • Function used to perform the Self Cleaning to prevent the Unit from Fungus and Bad Odors. • Used after the Shut Down of Cooling Operation to Clean the Evaporator and keep it as fresh for the Next operation. •...
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Operation Preheat • This is operation to preheat the compressor by conducting current through motor coils of the compressor for pre- venting phenomena that liquid refrigerants are income due to difference between temperature of the outside pipe and temperature of the compressor as outdoor temperature becomes low. •...
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Operation 10sec Tact S/W Buzzer sound Operation LED Flickering 4 times 0.25sec (1time) When selecting additional heat Logic 1.5sec 1.5sec 1.5sec 0.25*3 sec (2times) When selecting existing heat Logic 1.5sec 1.5sec 1.5 sec Indoor fan lock detection (BLDC) • Function of operation off for preventing overload when the indoor fan stops in the operating condition of the outdoor unit.
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Operation Remote Control Operations The controls will look like the following. 1. START/STOP BUTTON Used to turn off/on the unit. Signal transmitter 2. OPERATION MODE SELECTION BUTTON Used to select the operation mode. 3. ROOM TEMPERATURE SETTING BUTTONS Used to select the room temperature. 4.
Disassembly Disassembly Indoor Unit Disconnect the unit from power supply before mak- ing any checks. Be sure the power switch is set to “OFF”. To remove the Grille from the Chassis. • Set the up-and-down air discharge louver to open position (horizontally) by finger pressure.
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Disassembly 2. To remove the Control Box. • Remove securing screws. • Pull the control box out from the chassis carefully. Screw 3. To remove the Discharge Grille. • Unhook the discharge grille and pull the discharge grille out from the chassis carefully. 4.
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Disassembly • Unhook the tab on the right inside of the chassis at the same time, slightly pull the evaporator toward you until the tab is clear of the slot. 5. To remove the Motor Cover • Remove 2 securing screw. •...
Troubleshooting Guide Troubleshooting Guide Refrigeration Cycle Diagram (1) Cooling Only Models INDOOR UNIT OUTDOOR UNIT LIQUID SIDE 3-WAY VALVE HEAT HEAT EXCHANGE EXCHANGE (EVAPORATOR) (CONDENSER) GAS SIDE REVERSING 3-WAY VALVE ACCUMU VALVE LATOR COOLING COMPRESSOR HEATING (2) Cooling & Heating Models INDOOR UNIT OUTDOOR UNIT LIQUID SIDE...
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Troubleshooting Guide 2-way, 3-way Valve 2-way Valve (Liquid Side) 3-way Valve (Gas Side) Valve cap Hexagonal wrench (4mm) Open position Flare nut Flare nut Closed position Open position Closed position piping piping Service Service connection connection port cap port To outdoor unit To outdoor unit Works Shaft position...
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Troubleshooting Guide Air purging Required tools : hexagonal wrench, adjustable wrench, The air in the indoor unit and in the piping must be torque wrenches, wrench to hold the purged. If air remains in the refrigeration pipes, it will joints, and gas leak detector. affect the compressor, reduce to cooling capacity, and could lead to a malfunction.
Troubleshooting Guide Pumping Down Liquid side Indoor unit Open Outdoor unit 2-Way valve Gas side Closed 3-Way valve CLOSE CLOSE Purge the air • Procedure (6) Operate the air conditioner at the cooling (1) Confirm that both the 2-way and 3-way valves cycle and stop it when the gauge indicates are set to the open position.
Troubleshooting Guide Re-air Purging (Re-installation) Liquid side Indoor unit Closed Outdoor unit 3-Way valve Gas side Closed 3-Way valve Gas cylinder OPEN CLOSE • Procedure (6) Disconnect the charge set and the gas cylin- (1) Confirm that both the liquid side valve and the der, and set the Liquid side and Gas side gas side valve are set to the closed position.
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Troubleshooting Guide Balance Refrigerant of the 3-way Valve (Gas leakage) Liquid side Indoor unit Outdoor unit 3-Way valve Open Gas side 3-Way valve Open OPEN CLOSE • Procedure (1) Confirm that both the 2-way and 3-way valves (3) Open the valve (Lo side) on the charge set and are set to the back seat.
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Troubleshooting Guide Evacuation (All amount of refrigerant leaked) Liquid side Indoor unit Outdoor unit 3-Way valve Open Gas side 3-Way valve Open Vacuum pump OPEN CLOSE • Procedure (1) Connect the vacuum pump to the center hose (3) Close the valve (Lo side) on the charge set, of charge set center hose turn off the vacuum pump, and confirm that the gauge needle does not move (approxima-...
Troubleshooting Guide Gas Charging (After Evacuation) Liquid side Indoor unit Outdoor unit Open 3-Way valve Gas side Open 3-Way valve Check valve Charging cylinder OPEN CLOSE • Procedure This is different from previous procedures. (1) Connect the charge hose to the charging Because you are charging with liquid refrigerant cylinder.
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Troubleshooting Guide Cycle Parts Trouble analysis 1. Check temperature difference between intake and discharge air and operating current. Temp. difference : approx. 0°C • All amount of refrigerant leaked Current : less than 80% of out. Check refrigeration cycle. rated current Temp.
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Troubleshooting Guide Self diagnosis Function Indoor Error Display Cause of Error Error Indicator Operation Code Indoor Outdoor 1 time 1time 1time 1time 1time • Indoor Temp. sensor error - Sensor open or short 3 sec 3 sec 3 sec 3 sec 2times 2times 2times...
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Troubleshooting Guide 1. Error indicator of air conditioner 1) Indoor : Operating LED / Outdoor : LED01M(Red) on the outdoor PCB 2) 2 more errors occur at same time - Air conditioner Off condition : Display the error code of product off cause - Air conditioner On condition : Display the prior Error Code 2.
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Troubleshooting Guide Electronic Parts Refer to electronic contorol device drawing & schematic diagram. The Product doesn’t operate at all. Trouble 1 Turn off the main power and wait to 10 seconds Turn on the main power again. Does "Beeping" sound is made from the indoor unit? •...
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Troubleshooting Guide Product doesn't operate with the remote controller. Trouble 2 Turn on main power. While the compressor has been stopped, the compressor does not operate owing to the delaying function for 2 minutes after stopped. When the compressor stopped Indoor Fan is driven by a low speed. At this point the wind speed is not controlled by the remote controller.
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Troubleshooting Guide Troubleshooting for error code Error code Description Cause of error • Indoor TH. (sensor) is short or open Indoor TH. is short or • Indoor TH. (sensor) is not connected to the indoor pcb assembly • Damage or defect on the sensing circuit of indoor pcb assembly. open (R01H, R02H, R03H, R04H, C01H, C02H) Check flow...
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Troubleshooting Guide • 9K / 12K Error code Description Cause of error • Heat-sink TH. is damaged(short or open). Heat-sink Temp. is over 95°C • Heat-sink Temp. is over 95°C Heat-sink TH. • Damage or defect on the sensing circuit of outdoor pcb assembly. is open or short (R01H, R02H, C01H) Check flow...
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Troubleshooting Guide Error code Description Cause of error • Wrong or missing wiring between indoor and outdoor unit cable • Defect of communication components in indoor pcb assembly • Defect of communication components in outdoor pcb assembly Communication Error • Defect of power supply components in outdoor pcb assembly •...
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Troubleshooting Guide Cause of error Error code Description Cause of error • Supplied power is not normal • Comp Connector (CN-U,V,W) is disconnected or inserted to wrong position DC Peak Error • Compressor is damaged (coil short) replace compressor • Too much Refrigerant •...
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Troubleshooting Guide Error code Description Cause of error • Supplied power is not normal Over current Error • Indoor/outdoor fan is locked • Too much refrigerant (CT2) • Defect in current sensing circuit in outdoor pcb assembly Check flow Supplied voltage to Does indoor / outdoor fan work Outdoor pcb is about Refrigerant pressure is right ?
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Troubleshooting Guide Error code Description Cause of error • Indoor fan is locked or separated Indoor fan is locked • Fan connector is not connected to indoor pcb assembly (BLDC fan model only) • Defective in DC-fan driving circuit Check flow Indoor fan is rotating ? (1) Indoor fan is rotating ? (2) DC–fan driving circuit is right ?
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Troubleshooting Guide Error code Description Cause of error • D_pipe TH. is short or open D-Pipe TH. is short or • D_pipe TH. is not connected to the outdoor pcb assembly open • Damage or defect on the sensing circuit of outdoor pcb assembly Check flow D_PIPE TH.