Multi Type Air Conditioner Service Manual TABLE OF CONTENTS Safety Precautions............................3 Details of LG Model Name..........................7 Product Specifications ..........................8 Combination Table ............................12 Dimensions..............................15 Refrigeration Cycle Diagram........................17 Schematic Diagram...........................19 Functions ..............................24 Operation Details ............................31 2-way, 3-way Valve ............................38 Cycle Troubleshooting Guide ........................42 Electronic Parts Troubleshooting Guide....................44...
Safety Precautions Safety Precautions To prevent injury to the user or other people and property damage, the following instructions must be followed. Incorrect operation due to ignoring instruction will cause harm or damage. The seriousness is classified by the following indications. WARNING This symbol indicates the possibility of death or serious injury.
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Safety Precautions Do not modify or extend the Do not install, remove, or re- Be cautious when unpacking power cable. install the unit by yourself and installing the product. (customer). • There is risk of fire or electric shock. • There is risk of fire, electric shock, •...
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Safety Precautions Do not store or use flammable gas or com- If strange sounds, or smell or smoke comes bustibles near the product. from product. Turn the breaker off or discon- nect the power supply cable. • There is risk of fire or failure of product. •...
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Safety Precautions CAUTION Installation check for gas (refrigerant) Install the drain hose to Keep level even when leakage after installation or ensure that water is drained installing the product. repair of product. away properly. • Low refrigerant levels may cause fail- •...
Details of LG Model Name Details of LG Model Name Outdoor Unit L 4 U H 6 0 2 F A 0 Development Sequence Function A: Basic Multi Type F: Free joint multi Electric Standard (Volts / Freq. / Phase) 2: 220V / 60Hz / 1Ø...
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Locked Rotor Amp. 68/26 68/26 (TPS Cycle) Type Rotary Rotary Quantity Model QP348KCC/QK185KAF QP348KCC/QK185KAF Maker LG/LG LG/LG Capacity kcal/h(Btu/h) 25700/12900 25700/12900 Motor Type Single Phase Induction Motor / PSC Single Phase Induction Motor / PSC Motor Input 2424/1205 2424/1205 Oil Type...
Dimensions Dimensions 1. Indoor Unit 1. Split Type Installation plate MODEL SR 12K ST 18K/24K W(mm) 1080 H(mm) D(mm) 2. Duct Type BT/BT1 MODEL BT 12K BT1 18K BH 24K W(mm) 1060 H(mm) D(mm) Service Manual 15...
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Dimensions 2. Outdoor Unit MODEL 48K/60K Btu/h 16 Multi Type Air Conditioner...
Refrigeration Cycle Diagram Refrigeration Cycle Diagram 1. L3UH482FA0 Indoor Side Outdoor Side 4- WAY Valve COMP COMP 4- WAY Valve COMP 2. L3UC482FA0 Indoor Side Outdoor Side COMP COMP COMP Capillary 3-Way Valve 2-Way Valve Solenoid Valve L.E.V Service Manual 17...
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Refrigeration Cycle Diagram 3. A4UH602FA0 Indoor Side Outdoor Side 4- WAY Valve COMP COMP 4- WAY Valve COMP 4. A4UC602FA0 Indoor Side Outdoor Side COMP COMP COMP Capillary 3-Way Valve 2-Way Valve Solenoid Valve L.E.V 18 Multi Type Air Conditioner...
Schematic Diagram Wiring Diagram 1. Indoor Unit Split Type Indoor Unit Duct Type Indoor Unit - BT chassis AC PCB ASM DC PCB ASM WIRING DIAGRAM THERMISTOR(OUT-PIPE) ROOM. IN-PIPE. OUT-PIPE. CENTRAL CONTROL REMOTE A/CL THERMISTOR THERMISTOR THERMISTOR TELE CONTROL CONTROL UNIT HEATER THERMISTOR(IN-PIPE)
Functions Functions Split Type Indoor Unit Operation ON/OFF by Remote controller Sensing the Room Temperature • Room temperature sensor. (THERMISTOR) Room temperature control • Maintains the room temperature in accordance with the Setting Temp. Starting Current Control • Indoor fan is delayed for 5 sec at the starting. Time Delay Safety Control •...
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Functions Split Type Remote Controller 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...
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Functions Signal Receptor Receives the signals from the remote controller.(Signal receiving sound: two short beeps or one long beep.) Operation Indication Lamps On/Off : Lights up during the system operation. Sleep Mode : Lights up during Sleep Mode Auto operation. Signal receptor Timer...
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Functions Remote Control Operation The Remote Controller transmits the signals to the system. START/STOP BUTTON Operation starts when this button is pressed and stops when the button is pressed again. OPERATION MODE SELECTION BUTTON Used to select the operation mode. (Cooling Only) Signal transmitter (Heat Pump)
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Functions Duct Type Remote Controller Operation ON/OFF Operation Mode Selection Cooling Operation Mode ( Soft Dry Operation Mode ( Heating Operation Mode ( Auto Operation Mode ( (Cooling (Heating model only) model only) Fan Speed Selection (Low) (Med) (High) Room Temperature Display : High:39°C ↔...
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Functions Remote Control Operation AUTO SWING OPERATION SET TEMP FAN SPEED SUB FUNCTION Room Temp AUTO Heater Preheat Defrost Humidify Filter Out door 1 2 3 4 Time ZONE Timer Operation unit Program set Set no. Time Signal receiver Timer Cancel Program Week...
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Functions Outdoor Unit Two Comp algorithm • Inverter Comp is first priority and then Constant Comp is turning on responding to load condtion. Operating Frequency • Inverter Frequency varies considering condition such as room temp,outdoor temp, operating room number,Temp gap between room temp and set temp and so on. LEV Control •...
Operation Details Operation Details Main Unit Function 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) Sleep Timer Indicator •...
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Operation Details • 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 4-min compressor off repeat. Compressor ON Temp.
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Operation Details Fuzzy Operation (C/O Model) • According to the temperature set by Fuzzy rule, when the intake air temp is 0.5°C or more below the setting temp, the compressor is turned off. When 0.5°C or more above the setting temp, the compressor is turned on. Compressor ON Temp Setting Temp + 0.5°C Compressor OFF Temp...
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Operation Details 2) Fuzzy Operation for Dehumidification • According to the setting temperature selected by Fuzzy rule, when the intake air temp is 0.5°C or more below the setting temp, the compressor is turned off. When 0.5°C or more above the setting temp, the compressor is turned on.
Operation Details Off-Timer Operation • When the set time is reached after the time is input by the remote control, the appliance stops operating. • The timer LED is on when the off-timer is input. It is off when the time set by the timer is reached. •...
Operation Details Jet Cool Mode Operation (C/O Model) • If the Jet Cool key is input at any operation mode while in appliance operation, the Jet Cool mode operates. • In the Jet Cool mode, the indoor fan is operated at super-high speed for 30 min at cooling mode operation. •...
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Operation Details Remote Control Operation Mode • When the remote control is selected by the slide switch on the main unit, the appliance operates according to the input by the remote control. Protection of the evaporator pipe from frosting • If the indoor pipe temp is below 0°C in 7 min. after the compressor operates without any pause while in cool- ing cycle operation mode, the compressor and the outdoor fan are turned off in order to protect the indoor evaporator pipe from frosting.
2-way, 3-way Valve 2-way, 3-way Valve 2-way Valve (Liquid Side) 3-way Valve (Gas Side) Valve cap Hexagonal wrench Open position (4mm) Closed position Flare nut Flare nut Open position Closed position piping piping Service Service connection connection port cap port To outdoor unit To outdoor unit Works...
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2-way, 3-way Valve (1) Pumping down Liquid side Indoor unit Outdoor unit Close 2-Way valve Gas side Open 3-Way valve Liquid side Indoor unit Close 2-Way valve Gas side Open 3-Way valve manifold gauge Low- handle Hi- handle (CLOSE) (CLOSE) Procedure •...
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2-way, 3-way Valve (2) Evacuation (All amount of refrigerant leaked) Liquid side Indoor unit Outdoor unit Open 2-Way valve Gas side Open 3-Way valve Liquid side Indoor unit Open 2-Way valve Gas side Open 3-Way valve manifold gauge Vacuum pump Low- handle Hi- handle...
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2-way, 3-way Valve (3) Gas Charging (After Evacuation) Liquid side Indoor unit Outdoor unit Open 2-Way valve Gas side Open 3-Way valve Liquid side Indoor unit Open 2-Way valve Gas side Open 3-Way valve manifold gauge Charging cylinder Low-handle Hi- handle (OPEN) Check valve (OPEN)
Cycle Troubleshooting Guide Cycle Troubleshooting Guide Trouble analysis 1. Check temperature difference between intake and discharge air, and operating current. Temp. difference : approx. 0°C All amount of refrigerant leaked out. Current : less than 80% of Check refrigeration cycle. rated current Temp.
Electronic Parts Troubleshooting Guide Electronic Parts Troubleshooting Guide 1. The Outdoor Unit does not operate at all Does the Operating LED of indoor unit blink Refer to the self-diagnosis function. when Operation’s ON? Is the Connection between CN-Power of indoor Check the connecting state of connector unit and terminal block? Indoor...
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Electronic Parts Troubleshooting Guide 2. The product is not operate with the remote controller. Turn on Main Power While the compressor has been stopped, the compressor does not operate owing to the delaying function for 3 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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Electronic Parts Troubleshooting Guide 3. When cooling does not operate Turn on Main Power Operate "Cooling Mode( )" by setting the desired temperature of the remote controller is less than one of the indoor temperature by 1°C at least. When in Air Circulation Mode, Compressor/Outdoor Fan is stopped. Check the sensor for indoor temperature is attached as close as to be effected by the temperature of Heat Exchanger(EVA).
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Electronic Parts Troubleshooting Guide 4. When Heating does not operate Turn ON Main Power Operate “Heating Mode( )” by setting the desired temperature of the remote control is higher than one of the indoor temperature by 2°C at least. In heating Mode, the indoor fan operates in case the pipe temperature is higher than 28°C.
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Electronic Parts Troubleshooting Guide 5. When indoor Fan does not operate Turn off Main power Check the connection of CN-FAN or CN-MOTOR Check the Fan Motor Check the Fuse(AC250V/T2A) Check the related circuit of indoor Fan Motor. • The pin of Micom, and the part for driving SSR •...
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Electronic Parts Troubleshooting Guide 6. When Vertical Louver does not operate • Confirm that the Vertical Louver is normally geared with the shaft of Stepping Motor. • If the regular torque is detected when rotating the Vertical Louver with hands Normal •...
Disassembly of the parts (Indoor unit) Disassembly of the parts (Indoor unit) 1. SR/ST Chassis Warning : Disconnect the unit from power supply before making any checks. Be sure the power switch is set to “OFF”. To remove the Grille from the Chassis. •...
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Disassembly of the parts (Indoor unit) 3. To remove the Discharge Grille. • Unhook the discharge grille and pull the discharge grille out from the chassis carefully. 4. To remove the Evaporator. • Remove 3 screws securing the evaporator(at the left 2EA in the Eva Holder, at the right 1EA).
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6. 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.