8 : 380~415V /50Hz / 3ø Cooling/Heating Capacity 18: 18,000 Btu/hr 36: 36,000 Btu/hr 24: 24,000 Btu/hr 48: 48,000 Btu/hr Chassis Type D : D Chassis E : E Chassis Type of Air Conditioner LT: LG Ceiling Cassette Type Air Conditioner –3–...
Functions 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. • Indoor fan is delayed for 5 seconds at the starting. Starting Current Control •...
Page 5
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 AUTO (Low) (Med) (High) Room Temperature Display : High:39°C ↔...
Dimensions (1) Indoor Unit • Model : LT-E1860RJ/RH, LT-E2460RJ/RH CLOSE OPEN OPEN CLOSE –8–...
Page 9
• Model : LT-D3680RJ/RH, LT-D3680FJ/FH LT-D4880RJ/RH, LT-D4880FJ/FH –9–...
Page 10
(2) Outdoor Unit • Model : LT-E1860RJ/RH, LT-E2460RJ/RH LT-D3680RJ/RH, LT-D3680FJ/FH Gas side 3-way valve Liquid side 2(3)-way valve MODEL LT-E1860RJ/RH LT-D3680RJ/RH LT-E2460RJ/RH LT-D3680FJ/FH 74.5 74.5 –10–...
Page 11
• Model : LT-D4880RJ/RH, LT-D4880FJ/FH Liquid side 3-way valve Gas side 3-way valve Model LT-D4880RJ/RH LT-D4880FJ/FH Dimension 1225 1135 –11–...
Refrigeration Cycle Diagram • HEAT PUMP 18K/24K INDOOR UNIT OUTDOOR UNIT H/EX VALVE REVERSING Liquid Side Liquid Side Gas Side H/EX CAPI Heating Cooling COMPRESSOR Liquid Side Gas Side Gas Side CAPI 36K/48K INDOOR UNIT OUTDOOR UNIT H/EX VALVE REVERSING Liquid Side Liquid Side Gas Side...
Wiring Diagram • HEAT PUMP Model No.: LT-E1860RJ/RH, LT-E2460RJ/RH OUTDOOR WIRING DIAGRAM INDOOR WIRING DIAGRAM WIRING OF FIELD CAPACITOR INDOOR DRAIN STEP MOTOR PUMP MOTOR CAPACITOR MOTOR COMP REMOVE JUMP WIRE FUSE T3.15A WHEN CONNECTING FIRE ALARM SYSTEM PIPE THERMISTOR...
Page 14
Model No.: LT-D4880RJ/RH OUTDOOR WIRING DIAGRAM INDOOR WIRING DIAGRAM REMOVE JUMP WIRE WHEN CONNECTING FIRE ALARM SYSTEM Fuse (250V 5A) pipe TH INDOOR DRAIN STEP MOTOR PUMP MOTOR Fuse T/B3 (250V 5A) FUSE T3.15A FUSE T3.15A PIPE THERMISTOR S T N CRANK-CASE HEATER T/B1...
Page 15
• COOLING ONLY Model No.: LT-D3680FJ/FH OUTDOOR WIRING DIAGRAM INDOOR WIRING DIAGRAM COMPRESSOR C TH THERMISTOR FOR PIPE TEMP. MAGNECTIC CONTACOR OUTDOOR FAN MOTOR INDOOR DRAIN STEP CRANK CASE HEATER FOR CM FUSE 250V, 5A MOTOR PUMP MOTOR RUN CAPACITOR FOR FMo TERMINAL BLOCK(FOR JUMP) TERMINAL BLOCK(FOR POWER) FUSE T3.15A...
Operation Details (1) The function of main control 1. Time Delay Safety Control • 3min The compressor is ceased for 3minutes to balance the pressure in the refrigeration cycle. (Protection of compressor) • 5sec Vertical louvers are delayed for 5 secs to be opened to prevent the frictional sound between louver and air flow. •...
Page 17
6. Heating Mode Operation The unit will operate according to the setting by the remote controller and the operation diagram is shown as follows. Intake Air temp. minimum 3min Setting temp.+3°C (Compressor OFF) Setting temp. (Compressor ON) minimum minimum minimum 1min 10sec.
Page 18
8. Defrost Control • Defrost control is available 45 minutes later since heating mode operation started, and it will not prolong over 10 minutes. • Defrost control is carried out when the outdoor pipe temp. falls below -6°C for more than 3 minutes after 45 minutes passed from starting of heating operation.
Installation of Indoor, Outdoor Unit 1. Selection of the best location 1) Indoor unit • There should not be any heat source or steam near the unit. • There should not be any obstacles to the air cir- culation. Ceiling •...
Page 20
2. Ceiling opening dimensions and hanging bolt location • The dimensions of the paper model for installing are the same as those of the ceiling opening dimensions. 600 (Ceiling opening) 18K/24K Ceiling 521(Hanging bolt) 39.5 39.5 Level gauge CAUTION 570 Unit size •...
Page 21
3. The Indoor Unit Installation Ceiling Keep the length of the bolt Hanging bolt from the bracket to 40mm (W3/8 or M10) Flat washer for M10 Air Conditioner body (W3/8 or M10) (accessory) Ceiling board Ceiling board Spring washer (M10) Flat washer for M10 (accessory) Set screw of...
Page 22
WIRED REMOTE CONTROL INSTALLATION DISASSEMBLING • Separate the under plate from Remote control box. Front case Lever carefully Remote control the box open box body using a screw • Fix the cord clamps on the wall by ø 3 tapping driver, etc.
Page 23
5. Wiring Connection • Open the control box cover and connect the Remote controller cord and Indoor power wires. Indoor power cord Control box cover Remote [Air inlet side view] controller cord Control box cover fitting screw(2 units) • 18K/24K, 1 Phase Terminal Block of Indoor Unit Terminal Block of Outdoor Unit Heat Pump Model...
Page 24
ELECTRICAL WIRING 1. All wiring must comply with LOCAL REGULATIONS. 2. Select a power source that is capable of supplying the current required by the air conditioner. 3. Feed the power source to the unit via a distribution switch board designed for this purpose. 4.
Page 25
6. Connecting Pipes to the Indoor Unit • Preparation of Piping Main cause of gas leakage is defect in flaring work. Carry out correct flaring work in the following procedure. 1) Cutting the pipes and the cable Use the accessory piping kit or the pipes purchased Copper locally.
Page 26
Piping Connection 1. Form the piping according to its routing. Avoid bend- ing and bending back the same piping point more Liquid side than three times. (This will result in hardening of pipe.) Indoor 2. After deforming the piping, align centers of the union unit fitting of the indoor unit and the piping, and tighten Outdoor...
Page 27
7. Installation of Decorative Panel The decorative panel has its installation Before installing the decorative panel, direction. always remove the paper template. 1. Temporarily fix two decorative panel fixing screws (hexagon M5 screw) on the unit body. (Tighten by amount 10mm in length.) The fixing screws (hexagon M5 screw) are included the indoor unit box.
Page 28
CAUTION Install certainly the decorative panel. Cool air leakage causes sweating. Water drops fall. Good example Bad example Air conditioner unit Air conditioner Cool air leakage unit (no good) Ceiling Ceiling board board Decorative Decorative panel panel Fit the insulator (this part) and be careful for cool air leakage 8.
Page 29
HEAT INSULATION 1. Use the heat insulation material for the refrigerant piping which has an excellent heat-resistance (over 120°C). Fastening band 2. Precautions in high humidity circumstance: (accessory) This air conditioner has been tested according to the "KS Standard Conditions with Mist" and confirmed that there is not any default.
Page 30
Seal a small opening In case of the Outdoor Unit being installed around the pipings above position of the Indoor Unit. with gum type sealer. Trap 2. Tape the Pipings and Connecting cable from bot- tom to top. 3. Form the pipings gathered by taping along the exterior wall, and make the trap prevent water from entering into the room.
Page 31
2) Connection of power supply 1. Connect the power supply cord to the independent power supply. • Circuit breaker is required. 2. Operate the unit for fifteen minutes or more. 3) Evaluation of the performance 1. Measure the temperature of the intake and dis- charge air.
Page 32
Optional Operation 1) Two Thermistor System (1) Open the rear cover of the wired remote-controller to set the mode. (2) Select one of three selectable modes as follows. • Position 1: The room temperature is controlled by the thermistor of the main body. •...
Page 33
2) Adjusting air volume to the height of ceiling You can choose the RPM(or air volume) of indoor motor according to the height of ceiling to supply the com- fortable atmosphere to consumers. Procedure 1. Choose the selectable position in the table after measuring the height of ceiling. Ceiling height Mode of slide switch Change of air volume...
Cycle 1. Installation (Connecting the piping between indoor and outdoor unit) Liquid side Indoor unit Outdoor unit 2(3)-Way valve Gas side 3-Way valve Gas cylinder R-407C Purge the air • Installation (1) Connect the piping between the indoor and (5) If there is no leakage, discharge N in piping outdoor unit firmly.
Page 35
2. Disconnection (on moving) Liquid side Indoor unit Closed Outdoor unit 2(3)-Way valve Gas side Closed 3-Way valve Retrieving Tank • Disconnection (1) Attach the charging hose (manifold gage) to (6) Disconnect the piping between indoor and the service port. outdoor unit and then put on service cap to –...
Page 36
3. Gas Charging (After Evacuation) Liquid side Indoor unit Open Outdoor unit 2(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.
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. Difference Refrigerant leakege Temp.
Electronic Parts Troubleshooting Guide Possible Trouble 1 : The unit does not operate. Check the FUSE Is the input voltage and the wiring diagram. AC230V? Is the input voltage Check the main P.C.B of IC03D about DC12V? pattern. Is the output voltage Exchange IC03D.
Page 39
Possible Trouble 2 : The indoor fan does not operate. Is it the HOT It is normal operation. START mode? Is IC01M operated Exchange IC01M. normally? Is the each Relay Exchange Relay. any problem? Check the fan motor and connector.(CN-MOTOR) Possible Trouble 3 : Ineffective Heating Adjust operation mode.
Page 40
Possible Trouble 4 : Auto Air direction louver does not operate. Is IC01M operated Exchange IC01M. normally? Check the motor and connector. (CN-LOUVER) : Wired remote controller does not operate. Possible Trouble 5 Check the parts of Is the LCD operated communication.