Room Air Conditioner SERVICE MANUAL MODELS: ASNW096F1G0 ASNW096FE/V/GG0 ASNW126F1G0 ASNW126FE/V/GG0 ASUW126FUGO ASNW126F2G0(A12AW2-NF6) ASUW126FUGO(A12AWU-UF6) 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 ...........................4 Dimensions .............................10 Installation............................12 Flaring work and connection of piping..................15 Checking the drainage and forming the pipings .................18 Air purging ............................19 Test running ............................22 Functions............................23 Operation............................27 Disassembly............................40 Troubleshooting Guide ........................42 Schematic Diagram ........................62...
LG Model Name LG Model Name 2006 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...
Safety Precautions Safety Precautions To prevent injury to the user or other people and property damage, the following instructions must be followed. I Incorrect operation due to ignoring instruction will cause harm or damage. The seriousness is classified by the following indications. This symbol indicates the possibility of death or serious injury.
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Safety Precautions Be cautious when unpacking For installation, always con- Do not install the product on a and installing the product. tact the dealer or an defective installation stand. Authorized Service Center. • Sharp edges could cause injury. • There is risk of fire, electric •...
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Safety Precautions Use a dedicated outlet for this Grasp the plug to remove the Do not place a heater or other appliance. cord from the outlet. Do not appliances near the power touch it with wet hands. cable. • There is risk of fire or electrical •...
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Safety Precautions Do not open the inlet grill of When the product is soaked Ventilate the product from the product during operation. (flooded or submerged), con- time to time when operating it (Do not touch the electrostatic tact an Authorized Service together with a stove, etc.
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Safety Precautions Do not install the product Use two or more people to lift Do not install the product where the noise or hot air and transport the air condi- where it will be exposed to from the outdoor unit could tioner.
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Safety Precautions Always insert the filter secure- Do not insert hands or other Do not drink the water drained ly. Clean the filter every two objects through the air inlet or from the unit. weeks or more often if neces- outlet while the air conditioner sary.
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 Hanger Hole Fix Hole Pipe Hole Model...
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 struc- •...
Installation Preparing Work for Installation Open panel front 1. Pull the upper part of the front panel. 2. Lift up the panel. 3. To detach the front panel, remove the two screws at the lower part. 4. Detach the front panel from the body. 5.
Installation Fixing Indoor Unit 1. Attach an Installation guide map on the 2. Look at suited horizon by horizontal desired surface. meter on the horizontal setting line, and fix lightly the map by adhesive tape. INSTALLATION GUIDE MAP Horizontality T I O 3.
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 Wrap the insulation material around the con- necting portion. •Overlap the connection pipe insulation material and the indoor unit pipe insulation material. Bind them together with vinyl tape so that there is no gap. Loop Plastic bands Insulation material Gas side piping...
Flaring work and connection of piping Bad case Outdoor unit • Following bending type from left to right may cause Gas side piping damage to the turbing. (Bigger diameter) Liquid side piping (Smaller diameter) Torque wrench Connection of the pipes-Outdoor Align the center of the pipings and sufficiently tighten the flare nut by hand.
Checking the drainage and forming the pipings Checking the drainage and forming the pipings Checking the drainage Form the piping To check the drainage. Form the piping by wrapping the connecting portion of the indoor unit with insulation mate- • Pour a glass of water on the evaporator. rial and secure it with two kinds of vinyl tapes.
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 Liquid side (1) Remove the caps from the 2-way and 3-way valves. (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 Gas side close it.
Air purging Panel Front Assembly 1. First, Check the side cover assembly exactly, and fix the power cord in the bottom groove of cover side left. 2. Assemble connecting lead wire with controller, fix the upper part of panel front, and match the lower part of panel front.
Test running Test Running 1. Check that all tubing and wiring have been properly Intake temperature Discharge air connected. 2. Check that the gas and liquid side service valves are fully open. Prepare remote controller 1. Remove the battery cover by pulling it according to the arrow direction.
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 S-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 •...
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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. •...
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Functions Remote Control Operation ON/OFF Operation Mode Selection Cooling Operation Mode.( Auto Operation Mode.( (Cooling (Heating Healthy Dehumidification Operation Mode.( Heating Operation Mode.( model only) model only) Fan Speed Selection (Low) (Med) (High) (CHAOS) Room, Temperature Display : (High:39°C Low:11°C) Temperature Setting Down to 18°C Down to 16°C...
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 •...
Operation Cooling mode operation • Operating frequency of compressor depend on the difference of the temperature. (= intake air Temp.- Compressor off Temp. • Compressor off temp.= setting temp. -0.5°C on temp. = setting temp. +0.5°C • If compressor operates at some operating frequency, the operating frequency of compressor cannot be changed within 30 seconds.
Operation Heating mode operation • Operating frequency of compressor depend on the difference of the temperature ( = desired temp. – indoor temp. ) • Compressor off temp. = setting temp. + 4 °C on temp. = setting temp. + 2 °C •...
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. •...
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.
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. •...
Operation Power relay control • Power relay turns on 1 second later after the power is input to the outdoor unit. ➔ ➔ • Control sequence : power on PTC operating power relay on Protection from total current control I CT1 control •...
Operation Portection from overheating of power module • If the temperature of the heat sink TH. reaches over Toff, the Compressor stop instantly. • It will be limited the compressor operating frequency according to the heat sink TH.(refer to below FIG.) •...
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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.
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.
Operation Remote Control Operations The controls will look like the following. 1. START/STOP BUTTON Used to turn off/on the unit. 2. OPERATION MODE SELECTION BUTTON Signal transmitter Used to select the operation mode. 3. ROOM TEMPERATURE SETTING BUTTONS Used to select the room temperature. 4.
Disassembly Disassembly Indoor Unit WARNING: Disconnect the unit from power supply before making any checks. Be sure the power switch is set to "OFF" 1. Open panel front • Pull the upper part of the front panel. • Lift up the panel. •...
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Disassembly 3. To remove the Evaporator. - Remove 4 screws securing the evaporator. - Pull the evaporator out from the chassis carefully. 4. Before removing the Turbo Fan. Air Guide - Remove the securing screws from the chassis. - Pull the drain pan, top cover and the air guide. Top Cover 5.
Troubleshooting Guide Troubleshooting Guide Refrigeration Cycle Diagram (1) Model Capillary Tube 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) Model Adopted Electrion Expansion Valve 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.
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.
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 2 times 2 times 2 times...
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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.
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.
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 •...
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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.