Mini-split single zone systems, mini split standard systems, flex multi split dual and tri-zone indoor units–cooling only, outdoor units–cooling only, indoor units–heat pump, outdoor units–heat pump (2 pages)
Room Air Conditioner SERVICE MANUAL MODELS: LAN121CNM (ASNC121ERH0) LAU121CNM (ASUC121EUH0) LA121HPMI (ASNH121ERH0) LA121HPMO (ASUH121EUH0) LAN121HNM (ASNH121ERH0) LAU121HNM (ASUH121EUH0) LA121CPMI (ASNC121ERH0) LA121CPMO (ASUC121EUH0) website http://www.lgservice.com CAUTION • BEFORE SERVICING THE UNIT, READ THE SAFETY PRECAUTIONS IN THIS MANUAL. • ONLY FOR AUTHORIZED SERVICE PERSONNEL.
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. This symbol indicates the possibility of death or serious injury. This symbol indicates the possibility of injury or damage to properties only.
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Operation Use a dedicated outlet for this appliance. • There is risk of fire or electric shock. 4 Room Air Conditioner For installation, always contact the dealer or an Authorized Service Center. • There is risk of fire, electric shock, explosion, or injury.
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• There is risk of property damage, failure of product, or electric shock. Do not let the air conditioner run for a long time when the humidi- ty is very high and a door or a window is left open.
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• There is risk of electric shock. Do not insert hands or other objects through the air inlet or outlet while the air conditioner is plugged in. • There are sharp and moving parts that could cause personal injury.
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• There is risk of fire, electric shock or damage to the plastic parts of the product. Use two or more people to lift and transport the air conditioner • Avoid personal injury. Do not use the product for special purposes, such as preserving foods, works of art, etc.
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• A dirty filter reduces the efficiency of the air condi- tioner and Use a firm stool or ladder when cleaning or main- taining the air conditioner. • Be careful and avoid personal injury. Disuse Do not recharge or disassemble the batteries. Do not dispose of batteries in a fire.
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 Model Dimension...
Outdoor Unit 1. 12k MODEL unit mm(inch) mm(inch) mm(inch) mm(inch) mm(inch) mm(inch) mm(inch) mm(inch) 10 Room Air Conditioner 770(30.3) 540(21.3) 245(9.6) 287(11.3) 518(20.4) 100(3.9) Gas side (3-way valve) Liquid side (2-way valve) 64(2.5) 10(0.4)
Introduction Symbols Used In This Manual This symbol alerts you to the risk of electric shock. This symbol alerts you to hazards that may cause harm to the air condi- tioner. NOTICE This symbol indicates special notes. Features Air Inlet Front Panel Air Intake Vents...
Read carefully, and then follow step by step. Installation Parts Installation plate Type "B" screw Installation Tools Figure Measuring Tape, Knife 12 Room Air Conditioner Type "A" screw and plastic anchor Name Figure Screw driver Electric Drill Hole Core Drill...
Installation Map NOTICE Installation parts you should purchase. Air Discarge Vertical Air deflector Operation Indication Lamps/ Air Inlet Vents Air Outlet Vents Signal Receptor Forced Operation Button Saddle Base Plate Installation plate Sleeve Bushing-Sleeve Putty(Gum Type Sealer) Bend the pipe as closely on the wall as possible, but be careful that it doesn't break.
R-22 -40.8 Do not handle the pipe by yourself (customer) High-pressure refrigerant may cause personal injury. - manifold gauge ,charging and any piping tools must be dedicated to R-410A systems. 14 Room Air Conditioner 100% Vapor pressure(25°C)(kg f/cnf) 15.9 100% Vapor density(25°C)(kg/m...
70cm(27.6in) of space. 3. Do not place animals and plants in the path of the warm air. 4. Take the air conditioner weight into account and select a place where noise and vibration are minimum. Rooftop Installations If the outdoor unit is installed on a roof structure, be sure to level the unit.
Ø12.7(1/2") Indoor unit Outdoor unit • Capacity is based on standard length and maximum allowance length is on the basis of reliability. • Oil trap should be installed every 5~7meters (16.4~23.0ft). 16 Room Air Conditioner Standard Length Evap m(ft) Ø6.35(1/4") 7.5(25)
How to Mount Installation Plate The wall you select should be strong and solid enough to prevent vibration 1. Mount the installation plate on the wall with type "A" screws. If mounting the unit on a concrete wall, use anchor bolts. •...
Connecting The Piping Indoor 1. Prepare the indoor unit's piping and drain hose for installation through the wall. 2. Remove the plastic tubing retainer(see the illus- tration by) and pull the tubing and drain hose away from chassis. 3. Replace only the plastic tubing holder 1, not the holder 2 in the original position.
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Drain pipe Indoor unit drain hose Vinyl tape(narrow) Adhesive 20 Room Air Conditioner Wrap the insulation material around the connecting 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.
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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. Tape the drain hose and the connecting cable. • Connecting cable Connecting pipe Drain hose...
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Drain hose 22 Room Air Conditioner Reroute the pipings and the drain hose across the back of the chassis. Indoor unit piping...
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Installation Installation Information. For left piping. Follow the instruction below. Correct case • Press on the upper side of clamp and unfold the tubing to downward slowly. Incorrect case • Following bending type from right to left may cause damage to the tubing. Service Manual 23...
• When tightening the flare nut with torque wrench, ensure the direction for tightening fol- lows the arrow on the wrench. Outside diameter inch Ø6.35 Ø9.52 Ø12.7 Ø15.88 Ø19.05 24 Room Air Conditioner Outdoor unit Torque kgf . cm 180~250 340~420 550~660 630~820 980~1210 Suction Line piping...
Connection of The Cable 1. Remove the cover control from the unit by loosening the 3 screws. 2. Dismount caps on the conduit panel. 3. Temporarily mount the conduit tubes on the conduit panel. 4. Properly connect both the power sup- ply and low voltage lines to the corre- sponding terminals on the terminal block.
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After the confirmation of the above conditions, prepare the wiring as follows: 1) Never fail to have an individual power circuit specifically for the air conditioner. As for the method of wiring, be guided by the circuit diagram posted on the inside of control cover.
Checking The Drainage • Pour a glass of water on the drain pan. • Ensure the water flows through the drain hose of the indoor unit without any leakage and goes out the drain exit. Leakage checking Drain pan checking Drain piping •...
Trap is required to prevent water from entering into electrical parts. 28 Room Air Conditioner In cases where the Outdoor unit is installed above the Indoor unit perform the following. • Tape the piping and connecting cable from down to up.
Air Purging Air and moisture remaining in the refrigerant system have undesirable effects as indicated below. • Pressure in the system rises. • Operating current rises. • Cooling(or heating) efficiency drops. • Moisture in the refrigerant circuit may freeze and block capillary tubing. •...
• Replace the valve caps at both gas and liquid side service valves and fasten them tight. This completes air purging with a vacuum pump. The air conditioner is now ready to test run. 30 Room Air Conditioner Suction Line...
Charging Each outdoor unit is factory charged (nameplate charge) for the evaporator as well as a 7.5m(25ft) line set. Any time a line set is used either shorter or longer then the nominal 7.5m(25ft) line set length the refrigerant charge has to be adjusted. Whether the line set is made shorter or longer you must adjust the charge based on how many ft of tubing are either added or removed based on 20g(0.22oz) of R-410A per meter(foot).
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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• When the indoor pipe temp is 42°C or above, defrost control is not carried out even if the condition is one of the defrost conditions above. • While in defrost control, the compressor is on and the indoor fan, the outdoor fan, and the 4 way valve are off. 34 Room Air Conditioner Setting Temp+0.5°C Setting Temp-0.5°C Setting Temp.
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Airflow Speed Selection • The airflow speed of the indoor fan is set to high, medium, low, or chaos (auto) by the input of the airflow speed selection key on the remote control. Sleep Timer Operation • When the sleep time is reached after <1,2,3,4,5,6,7,0(cancel) hr> is input by the remote control while in appliance operation, the operation of the appliance stops.
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• When the appliance-operation key is input by the remote control, the short "beep-beep-" sounds. • When the appliance-pause key is input by the remote control, the long "beep—" sounds. 36 Room Air Conditioner Heat pump Model Room Temp. 24°C(75.2°F) 21°C(69.8°F) Room Temp.
Auto Operation Healthy Dehumidification Operation Heating Operation • Cooling Model( ), Heat Pump Model( 38 Room Air Conditioner 1. START/STOP BUTTON Operation starts when this button is pressed and stops when the button is pressed again. 2. OPERATION MODE SELECTION BUTTON Used to select the operation mode.
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. • Open the front panel as shown, and Remove the Securing screws.
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4. To remove the Evaporator. • Remove 3 screws securing the evaporator(at the left 2EA in the Eva Holder, at the right 1EA). • When repair, do not damage the Caution label. 40 Room Air Conditioner Screw...
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• 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. •...
(1) Cooling Only Models INDOOR UNIT HEAT EXCHANGE (EVAPORATOR) (2) Cooling & Heating Models INDOOR UNIT HEAT EXCHANGE (EVAPORATOR) 42 Room Air Conditioner OUTDOOR UNIT LIQUID SIDE CAPILLARY TUBE GAS SIDE OUTDOOR UNIT CHECK VALVE LIQUID SIDE (Heating Model only) 3-WAY VALVE...
2-way, 3-way Valve Flare nut piping connection Works Shipping Air purging (Installation) Operation Pumping down (Transfering) Evacuation (Servicing) Gas charging (Servicing) Pressure check (Servicing) Gas releasing (Servicing) 2-way Valve (Liquid Side) Hexagonal wrench (4mm) Open position Closed position To outdoor unit Shaft position Closed (with valve cap)
Gas side Closed 3-Way valve CLOSE (6) Operate the air conditioner at the cooling cycle and stop it when the gauge indi- cates 1kg/cm (7) Immediately set the 3-way valve to the closed position. – Do this quickly so that the gauge ends up...
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0 kg/cm – If there is no air in the refrigerant cycle (the pressure when the air conditioner is not running is higher than 1 kg/cm charge the refrigerant until the gauge indi- cates 0.5 to 1 kg/cm...
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(2) Evacuation for approximately one hour. – Confirm that the gauge needle has moved toward -76 cmHg (vacuum of 4 mmHg or less). 46 Room Air Conditioner Liquid side 3-Way valve Open Gas side...
This unit is charged with R-410A. Pay attention not to charge R-22. Open Outdoor unit Open discharged. refrigerant while operating the air condi- tioner turn off the air conditioner before disconnecting the hose. port nut to a torque of 1.8 kg.m. Service Manual 47...
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Operating Suction Pressure (For R410A) (According to Indoor & Outdoor Temperature) P = 3 + 0.0123 x T Where, P 48 Room Air Conditioner (At operating the Unit for 10 minutes) Indoor Temp. (˚C) + 0.8 x T . g) : Suction Pressure(kg/cm Tout : Outdoor Temperature(˚C)
Cycle Parts Trouble analysis 1. Check temperature difference between intake and discharge air and operating current. Temp. difference : approx. °F(0°C) Current Temp. Difference Temp. difference : approx. 14°F(8°C) Current Operating Current Temp. difference : less than 14°F(8°C) Current Temp. difference : over 14°F(8°C) NOTICE Temperature difference between intake and discharge air depends on room air humidity.
• IC02D(7805) Output (Indoor unit) IC03D(7805) Output (Outdoor unit) • IC01A(KIA7036, Reset IC) Indoor : 16MHz Outdoor : 8MHz 50 Room Air Conditioner Turn off Main Power (After 20 seconds) Turn on Main Power Primarily, the operating condition of Micom is OK.
The product is not operate with the remote controller. 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.
IC01M, IC02M(No. 8) • Check the electrical wiring diagram of outdoor side. • Check the abnormal condition for the component of Compressor/Outdoor Fan Motor. 52 Room Air Conditioner Turn on Main Power )" by setting the desired temperature of the COMP ON...
When indoor Fan does not operate. Does the voltage of each terminals of CN-MOTOR CONNECTOR in Indoor unit corresponds to values in the Table of page 52 Does the voltage of terminal of CN-DC/DC CONNECTOR in Indoor unit corresponds to the values in the table of page 52 Do the voltage of terminal of Check the pattern and the CN-DC/DC CONNECTOR in...
- Between - Between - Between • Confirm the assembly conditions that are catching and interfering parts in the rotation radial of the Vertical Louver 54 Room Air Conditioner of MICOM of IC01M of IC01M of CN-UP/DOWN If there are no problems after above checks...
When a comunication error occurs. • The operation indicator of Indoor unit blinks five times. • The red indicator of Outdoor unit blinks five times. Check the connecting wires between Indoor and Outdoor unit for the connecting error and the contacting condition. Check the installation condition of outdoor unit.
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Short between terminals CN-DISP CN-TH Short between terminals Short between terminals 56 Room Air Conditioner Condition • The same as the phenomenon of Outdoor Unit. • The indoor fan does not operate. Open • The operation indicator of Indoor unit blinks 8 times.
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OUTDOOR UNIT Connector Type Condition CN-POWER Connecting reversely RY-COMP terminal Connecting reversely CN-TRANS CN-FAN The connecting wire of CN- DC/DC, and Indoor and Outdoor Unit Connecting error Blue Connecting error Black Brown Connecting error Connecting error Connecting error Connecting error •...
Product Specifications Cooling Only Item Unit Power Supply Cooling Capacity Input Running Current COMP. Locked Rotor AMP. S.E.E.R Air Circulation Moisture Removal Noise Level Indoor, High (Sound Pressure, 1m) Outdoor, Max Features Temperature Control Air Deflection Steps, Fan/Cool Air Deflection Control(up&down) Air Deflection Control(left&right) Remocon Type Setting Temperature Range, Cooling Mode...
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(WxHxD) Outdoor Net Weight Indoor Outdoor Net Weight Indoor Outdoor * Design and Specifications subject to change without prior notice for product improvement. 66 Room Air Conditioner LA*121HNM (AS-H121ERH0) Unit LA121HPM* (AS-H121ERH0) ø, V, Hz BTU/h BTU/h /min(cfm) l/h(pts/hr) dB(A)
HOSE ASSEMBLY,DRAIN 159830 FILTER ASSEMBLY,AIR CLEANER NOTE) Please ensure GCSC since these parts may be changed depending upon the buyer's request. (GCSC WEBSITE http://biz.LGservice.com) PART No. LAN121CNM(ASNC121ERH0) LAN121HNM(ASNH121ERH0) LA121CPMI(ASNC121ERH0) LA121HPMI(ASNH121ERH0) 3141A20034C 3141A20034C 5901A20017H 5901A20017H 4681AR2295L 4681AR2295L 4280A20004A 4280A20004A 3551A20156B 3551A20156B...
PANEL ASSEMBLY,FRONT(OUTDOOR) 435301 GRILLE,DISCHARGE 435511 COVER ASSEMBLY,CONTROL(OUTDOOR) NOTE) Please ensure GCSC since these parts may be changed depending upon the buyer's request. (GCSC WEBSITE http://biz.LGservice.com) 70 Room Air Conditioner PART No. LAU121CNM (ASUC121ERH0) LAU121HNM (ASUH121ERH0) LA121CPMO (ASUC121ERH0) LA121HPMO (ASUH12ERH0) 3041A20008K 3041A20008K...