website http://www.lgservice.com e-mail http://www.lgeservice.com/techsup.html System Heat Pump Air Conditioner SERVICE MANUAL MODELS: CRUN/CRNN Series CAUTION • BEFORE SERVICING THE UNIT, READ THE SAFETY PRECAUTIONS IN THIS MANUAL. • ONLY FOR AUTHORIZED SERVICE PERSONNEL.
Air Conditioner Service Manual TABLE OF CONTENTS Model Name Namerclature................3 Model Names....................4 Safety Precautions ..................5 Indoor Units .....................9 Ceiling Mounted Cassette Type (1 way)..........10 Ceiling Mounted Cassette Type (4 way)..........20 Ceiling Mounted Duct Type (High static) ..........36 Ceiling Mounted Duct Type (Low static)..........48 Convertible Type ..................58 Wall Mounted Type..................77 Art Cool Type (Mirror)................93...
Model Name Nomenclature Indoor Unit Serial Number Combinations of functions A: Basic Function Art Cool Type Panel Color B: Blue, C: Cherry, D: Wood, M: Metal N: Walnut, R: Mirror, W: White, G: Gold Chassis Name Electrical Ratings 1: 1ø, 100V~115V, 60Hz, 2: 1ø, 220V~240V, 60Hz 6: 1ø, 220V~240V, 50Hz, 7: 1ø, 100V~115V, 50Hz Total Cooling Capacity in Btu/h unit Ex) 5,000 Btu/h...
Safety Precautions Safety Precautions To prevent indury 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.
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Safety Precautions Cautions before installation Use the specified cables for wiring. Make the Always use accessories specified by LG connections securely so that the outside force Electronics. of the cable is not applied to the terminals. - Inadequate connection and fastening may gen- - Ask an authorized technician to install the erate heat and cause a fire.
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LG Electronics are used, fire or explosion may result. Do not install the unit where combustible gas Do not use the air conditioner where food, may leak.
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Safety Precautions Do not wash the air conditioner units. Be careful that the installation base is not damaged by long use. - Washing them may cause an electric shock. - If the damage is left uncorrected, the unit may fall and cause personal injury or property damage.
Functions 2. 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 temperature • Indoor fan is delayed for 5 seconds at the starting. Starting Current Control Time Delay Safety Control •...
Operation Details 3. Operation Details (1) The function of main control Time Delay Safety Control • 5sec Vertical louvers are delayed for 5 secs to be opened to prevent the frictional sound between louver and air flow. • 30sec The 4-way valve is ceased for 30sec. to prevent abnormal noise when the Heating operation is OFF or switched to the other operation mode while compress is off.
Operation Details 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 Temperature. minimum 3min Setting Temperature .+3°C (Compressor OFF) Setting Temperature (Compressor ON) minimum minimum 1min minimum...
Wiring Diagrams 6. Wiring Diagrams 1(L) 2(N) (Transmission) CONNECTOR SPEC COLOR DESCRIPTION NUMBER CN-POWER CN-POWER AC POWER SUPPLY WHITE AC POWER LINE INPUT FOR INDOOR CONTROLLER CN-MOTOR2 CN-MOTOR2 AC FAN MOTOR OUTPUT YELLOW MOTOR OUTPUT OF PHASE CONTROL CN-D/PUMP DRAIN PUMP OUTPUT WHITE AC OUTPUT FOR DRAIN PUMP CN-COMM...
Functions 2. 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 Temperature. • Indoor fan is delayed for 5 seconds at the starting. Starting Current Control Time Delay Safety Control •...
Operation detail 3. Operation detail (1) The function of main control Time Delay Safety Control • 5 sec ... Vertical air flow direction control louvers open in 5 seconds to prevent noise between louvers and wind. • 5 sec ... The 4-way valve is ceased for 5 sec. to prevent the refrigerant-gas abnormal noise when the Heating operation is OFF or switched to the other operation mode when compress is off.
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Operation detail Heating Mode Operation The unit will operate according to the setting by the remote controller and the operation diagram is shown as following. Intake Air temperature minimum 3min Setting Temperature .+3°C (Compressor OFF) Setting Temperature (Compressor ON) minimum minimum minimum 1min...
Dimensional Drawings 4. Dimensional Drawings CRNN126TEA0, CRNN186TEA0, Ceiling Ceiling Board Ceiling Board 50 or 50 or more more Unit:cm Floor CLOSE OPEN OPEN CLOSE (unit:mm) Indoor Unit...
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Dimensional Drawings CRNN246TDA0, CRNN286TDA0, CRNN366TDA0 CRNN426TDA0, CRNN486TDA0 Ceiling Ceiling Board Ceiling Board 50 or 50 or more more Unit:cm Floor (unit:mm) Service Manual 27...
Wiring Diagrams 6. Wiring Diagrams 1(L) 2(N) (Transmission) CONNECTOR SPEC COLOR DESCRIPTION NUMBER CN-POWER CN-POWER AC POWER SUPPLY WHITE AC POWER LINE INPUT FOR INDOOR CONTROLLER CN-MOTOR2 CN-MOTOR2 AC FAN MOTOR OUTPUT YELLOW MOTOR OUTPUT OF PHASE CONTROL CN-D/PUMP DRAIN PUMP OUTPUT WHITE AC OUTPUT FOR DRAIN PUMP CN-COMM...
Functions 2. 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 Temperature. • Indoor fan is delayed for 5 seconds at the starting. Starting Current Control Time Delay Safety Control •...
Operation Details 3. Operation Details (1) The function of main control Time Delay safety Control • 30sec ... The 4-way valve is ceased for 30sec. to prevent the refrigerant-gas abnormal noise when the Heating operation is OFF or switched to the other operation mode while compress is off. While compressor is running, it takes 3~5 seconds to switch to another mode.
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Operation Details Heating Mode Operation The unit will operate according to the setting by the remote controller and the operation diagram is shown as following. Intake Air Temperature minimum 3min Setting Temperature +3°C (Compressor OFF) Setting Temperature (Compressor ON) minimum minimum 1min 10sec.
Wiring Diagrams 6. Wiring Diagrams 1(L) 2(N) (Transmission) CONNECTOR SPEC COLOR DESCRIPTION NUMBER CN-POWER CN-POWER AC POWER SUPPLY WHITE AC POWER LINE INPUT FOR INDOOR CONTROLLER CN-MOTOR2 CN-MOTOR2 AC FAN MOTOR OUTPUT YELLOW MOTOR OUTPUT OF PHASE CONTROL CN-D/PUMP CN-D/PUMP DRAIN PUMP OUTPUT WHITE AC OUTPUT FOR DRAIN PUMP...
Functions 2. 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 Temperature. • Indoor fan is delayed for 5 seconds at the starting. Starting Current Control Time Delay Safety Control •...
Functions 3. Operation Details (1) The function of main control Time Delay safety Control • 30sec ... The 4-way valve is ceased for 30sec. to prevent the refrigerant-gas abnormal noise when the Heating operation is OFF or switched to the other operation mode while compress is off. While compressor is running, it takes 3~5 seconds to switch to another mode.
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Operation Details Heating Mode Operation The unit will operate according to the setting by the remote controller and the operation diagram is shown as following. Intake Air Temperature minimum 3min Setting Temperature +3°C (Compressor OFF) Setting Temperature (Compressor ON) minimum minimum 1min 10sec.
Dimensional Drawings 4. Dimensional Drawings Model CRNN076BNG0 CRNN096BJG0 CRNN126BJG0 Front view Top view Inspection hole (unit: mm) (600X600) Control box Front Service Manual 53...
Wiring Diagrams 6. Wiring Diagrams (Transmission) CONNECTOR SPEC COLOR DESCRIPTION NUMBER CN-POWER CN-POWER AC POWER SUPPLY WHITE AC POWER LINE INPUT FOR INDOOR CONTROLLER CN-MOTOR2 CN-MOTOR2 AC FAN MOTOR OUTPUT YELLOW MOTOR OUTPUT OF PHASE CONTROL CN-D/PUMP CN-D/PUMP DRAIN PUMP OUTPUT WHITE AC OUTPUT FOR DRAIN PUMP CN-COMM...
Installstion 2. Installstion 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 Temperature. Starting Current Control Indoor fan is delayed for 5 seconds at the starting. Time Delay Safety Control Restarting is inhibited for approx.
Operation Details 3. Operation Details (1) The function of main control Time Delay Safety Control • 3min … The compressor is ceased for 3minutes to balance the pressure in the refrigeration cycle. (Protection of compressor) • 5sec … Vertical air flow direction control louvers open in 5 seconds to prevent noise between louvers and wind. •...
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Operation Details Cooling Mode Operation When selecting the Cooling( ) Mode Operation, the unit will operate according to the setting by the remote controller and the operation diagram is as following Intake Air Temperature COMP. ON (SET TEMPERATURE +0.5°C) COMP. OFF (SET TEMPERATURE -0.5°C) More than More than...
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Operation Details Natural wind by CHAOS logic For more fresh feeling than other fan speed mode, press the indoor fan Speed Selector and set to CHAOS mode. In this mode, the wind blows like natural breeze by auto- matically changing fan speed according to the CHAOS logic.
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Operation Details Heating Mode Operation The unit will operate according to the setting by the remote controller and the operation diagram is shown as following. • For Heating Model Indoor piping temperature 28°C 26°C Intake Air temperature Setting temperature +3.0˚C (Compressor OFF) Setting temperature minimum...
Operation Details Soft Dry Operation • During Soft Dry Operation, the compressor ON temperature is the setting temperature plus 1°C, the compressor OFF temperature is the setting temperature minus 0.5°C. • When the room temperature rises over the compressor ON temperature, the operation mode is switched to the cooling mode.
Operation Details Protection of the evaporator pipe from frosting mperature of the indoor coil is below -2°C after 7 minutes from starting the compressor, If the te the compressor and the outdoor fan is stopped, and then after 3 minute delay of the compressor and the temperature of the indoor coil is over 7°C, the compressor and the outdoor fan is reoper- ated.
Display Function 4. Display Function Operation Indicator • Coolling, Soft Dry, Fan, Heating Timer Indicator • Timer Mode Sleep Timer Indicator • Sleep Mode Deice Indicator • Hot-start, Deice Note) For normal operation after checking by test mode, you should press SW1 nine times for resetting or recon- nect the power cord.
Dimensional Drawings 5. Dimensional Drawings 1 2 0 0 (Rear Side) (Unit: mm) More than 20cm More than 20cm More than More than 20cm 20cm More than eye-level (Ceiling installation) (Floor/Wall installation) Indoor Unit...
Wiring Diagrams 7. Wiring Diagrams 1(L) 2(N) (Transmission) CONNECTOR SPEC COLOR DESCRIPTION NUMBER CN-POWER CN-POWER AC POWER SUPPLY WHITE AC POWER LINE INPUT FOR INDOOR CONTROLLER CN-MOTOR2 CN-MOTOR2 AC FAN MOTOR OUTPUT YELLOW MOTOR OUTPUT OF PHASE CONTROL CN-COMM CN-COMM COMMUNICATION WHITE COMMUNICATION BETWEEN INDOOR AND OUTDOOR...
Disassembly of the parts 8. Disassembly of the parts Warning : Disconnect the unit from power supply before making any checks. Be sure the power switch is set to “OFF”. 1. Remove the air filter. • Pull the inlet grille slightly toward you. •...
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Disassembly of the parts 4. Remove air guide upper, crossflow fan and motor. • Remove the screws of both sides and center securing the upper air-guide. • Remove 2 screws fastening the bracket of door switch. Door Switch • Remove a bearing assembly by removing a screw and the bearing cover.
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Disassembly of the parts 6. Remove the front panel. Diffuser frame • Remove the screws of both sides fixing the Diffuser front panel. frame • Push the upper side of front panel strongly to Hook pull out the front panel from the inner hook of diffuser frame.
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Disassembly of the parts 9. Remove the vane-upper, vane-lower and step motor. Step Motor • Remove 2 screws securing the step motor Vane Supporter assembly and pull it out from the vanes care- fully. • Unhook the vanes from the vane supporter and remove the upper vane and lower vane by pulling the center of vanes with care.
Functions 2. 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 temperature Starting Current Control • Indoor fan is delayed for 5 seconds at the starting. Time Delay Safety Control •...
Operation Details 3. Operation Details (1) The function of main control • DISPLAY Operation Indicator • On while in appliance operation, off while in appliance pause Sleep Timer Indicator • On while in sleep timer mode, off when sleep timer cancel or appliance operation pause Timer Indicator •...
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Operation Details • While in compressor off, the indoor fan is off when the indoor pipe temperature is below 33°C, when above 35°C , it operates with the low airflow speed. • If overloaded while in heating mode operation, in order to prevent the compressor from OLP operation, the outdoor fan is turned on/off according to the indoor pipe temperature •...
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Operation Details 2) Fuzzy Operation for Dehumidification • According to the setting temperature selected by Fuzzy rule, when the intake air temperature is 0.5°C or more below the setting temperature, the compressor is turned off. When 0.5°C or more above the setting temperature, the compressor is turned on.
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Operation Details Off-Timer <=> On-Timer Operation • When the set time is reached after the on/off time is input by the remote control, the on/off-timer operation is carried out according to the set time. Sleep Timer Operation • When the sleep time is reached after < 1,2,3,4,5,6,7,0(cancel) hour > is input by the remote control while in appliance operation, the operation of the appliance stops.
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Operation Details Forced Operation • Operation procedures when the remote control can't be used. • The operation will be started if the power button is pressed. • If you want to stop operation, re-press the button. Room temperature ≥ 24°C 21°C ≤...
Wiring Diagrams 6. Wiring Diagrams (Transmission) CONNECTOR SPEC COLOR DESCRIPTION NUMBER CN-POWER CN-POWER AC POWER SUPPLY WHITE AC POWER LINE INPUT FOR INDOOR CONTROLLER CN-MOTOR2 CN-MOTOR2 AC FAN MOTOR OUTPUT YELLOW MOTOR OUTPUT OF PHASE CONTROL CN-ACDC AC/DC CONNECTION WHITE CONNECTION BETWEEN AC PCB AND DC PCB CN-COMM CN-COMM...
Disassembly of the parts 7. Disassembly of the parts Warning : 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 of the parts 2. To remove the Control Box. • Remove securing screws. • Pull the control box out from the chassis carefully. 3. To remove the Discharge Grille. • Pull the discharge grille out from the chas- sis carefully. 4.
Functions 2. 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. Starting Current Control • Indoor fan is delayed for 5 sec at the starting. Time Delay Safety Control •...
Operation Details 3. Operation Details 1. MAIN UNIT FUNCTION • DISPLAY 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 Heating Mode Operation • When the intake air temp reaches +3°…above the setting temp, the compressor is turned off. When below the setting temp, the compressor is turned on. Compressor ON Temp. Setting Temp. Compressor OFF Temp. Setting Temp.+3°C •...
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Operation Details Fuzzy Operation • When any of operation mode is not selected like the moment of the power on or when 3 hrs has passed since the operation off, the operation mode is selected. • When determining the operation mode, the compressor, the outdoor fan, and the 4 way valve are off and only the indoor fan is operated for 15 seconds.
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Operation Details 3) Fuzzy Operation for Heating • According to the setting temperature selected by Fuzzy rule, when the intake air temp is 3°C or more above the setting temp, the compressor is turned off. When below the setting temp, the compressor is turned on. Compressor ON Temp Setting Temp Compressor OFF Temp...
Operation Details Chaos Swing Mode • By the Chaos Swing key input, the upper/lower vane automatically operates with the Chaos Swing or they are fixed to the desired direction. • While in Chaos Swing mode, the angles of cooling and heating cycle operations are different. <...
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Operation Details Test operation • During the TEST OPERATION, the unit operates in cooling mode at high speed fan, regardless of room temperature and resets in 18±1 minutes. • During test operation, if remote controller signal is received, the unit operates as remote controller sets. If you want to use this operation, open the front panel upward and Press the power button let it be pressed for about 3 seconds.
Display Function 4. Display Function Signal Receptor Each Icon turns on when the unit is operated, then the only Icon outline to be operated is bright. Cooling Mode Lights up during Cooling operation. (Outline) Auto Operation Mode Lights up during Auto operation. (Outline) Healthy Dehumidification Lights up during Healthy Dehumidification operation.
Wiring Diagrams 7. Wiring Diagrams MAIN PCB ASM THERMISTOR THERMISTOR MOTOR STEP MOTOR STEP MOTOR STEP FUSE MOTOR AC250V/T2A CN-HVB CN-VFD 1(L) 2(N) DISPLAY PURIFIER PCB ASM POWER INPUT TO OUTDOOR UNIT(Transmission) CONNECTOR SPEC COLOR DESCRIPTION NUMBER CN-POWER CN-POWER AC POWER SUPPLY WHITE AC POWER LINE INPUT FOR INDOOR CONTROLLER CN-MOTOR2...
Disassembly of the parts 8. Disassembly of the parts 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. • Hold up Inlet Grille Horizentally. •...
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Disassembly of the parts 2. To remove the Control Box. • Remove securing screws. • Pull the control box out from the chassis carefully. 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 of the parts • 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. •...
Functons 2. 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 temperature Starting Current Control • Indoor fan is delayed for 5 sec at the starting. Time Delay Safety Control •...
Operation Details 3. Operation Details (1) MAIN UNIT FUNCTION • DISPLAY 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 Heating Mode Operation • When the intake air temperature reaches +3°C above the setting temperature, the compressor is turned off. When below the setting temperature, the compressor is turned on. Compressor ON temperature Setting temperature Compressor OFF temperature Setting temperature+3°C •...
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Operation Details 2) Fuzzy Operation for Dehumidification • According to the setting temperature selected by Fuzzy rule, when the intake air temperature is 0.5°C or more below the setting temperature, the compressor is turned off. When 0.5°C or more above the setting temperature, the compressor is turned on.
Operation Details Off-Timer On-Timer Operation • When the set time is reached after the on/off time is input by the remote control, the on/off-timer operation is carried out according to the set time. Sleep Timer Operation • When the sleep time is reached after <1,2,3,4,5,6,7,0(cancel) hour > is input by the remote control while in appliance operation, the operation of the appliance stops.
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Operation Details Forced Operation • Operation procedures when the remote control can't be used. • The operation will be started if the power button is pressed. • If you want to stop operation, re-press the button. Room temperature ≥ 24°C 21°C ≤...
Wiring Diagrams 7. Wiring Diagrams TO OUTDOOR UNIT (TRANSMISSION) CONNECTOR SPEC COLOR DESCRIPTION NUMBER CN-POWER CN-POWER AC POWER SUPPLY WHITE AC POWER LINE INPUT FOR INDOOR CONTROLLER CN-MOTOR2 CN-MOTOR2 BLDC FAN MOTOR OUTPUT WHITE MOTOR OUTPUT OF BLDC CN-COM CN-COM COMMUNICATION WHITE COMMUNICATION BETWEEN INDOOR AND OUTDOOR...
Disassembly of the parts 8. Disassembly of the parts Warning : Disconnect the unit from power supply before making any checks. Be sure the power switch is set to “OFF”. 1. To remove the Grille from the Chassis. - Pull the grille bottom, the remove 2 securing screws. - Lift the both lower parts of panel front.
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Disassembly of the parts 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. Top Cover - Pull the pipe cover, top cover and the air guide.
Installation 2. Installation 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 •...
Operation Details 3. Operation Details 1. MAIN UNIT FUNCTION • DISPLAY 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 Heating Mode Operation • When the intake air temp reaches +3°…above the setting temp, the compressor is turned off. When below the setting temp, the compressor is turned on. Compressor ON Temp. Setting Temp. Compressor OFF Temp. Setting Temp.+3°C •...
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Operation Details Fuzzy Operation • When any of operation mode is not selected like the moment of the power on or when 3 hrs has passed since the operation off, the operation mode is selected. • When determining the operation mode, the compressor, the outdoor fan, and the 4 way valve are off and only the indoor fan is operated for 15 seconds.
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Operation Details 3) Fuzzy Operation for Heating • According to the setting temperature selected by Fuzzy rule, when the intake air temp is 3°C or more above the setting temp, the compressor is turned off. When below the setting temp, the compressor is turned on. Compressor ON Temp Setting Temp Compressor OFF Temp...
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Operation Details Chaos Swing Mode • By the Chaos Swing key input, the louvers vane automatically operate with the Chaos Swing or they are fixed to the desired direction. • While in Chaos Swing mode, the angles of cooling and heating cycle operations are different. <...
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Operation Details Auto restart • In case the power comes on again after a power failure, Auto Restarting Operation is the function to oper- ate procedures automatically to the previous operating conditions. 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.
Wiring Diagrams 7. Wiring Diagrams 1(L) 2(N) (Transmission) CONNECTOR SPEC COLOR DESCRIPTION NUMBER CN-POWER CN-POWER AC POWER SUPPLY WHITE AC POWER LINE INPUT FOR INDOOR CONTROLLER CN-MOTOR2 CN-MOTOR2 BLDC FAN MOTOR OUTPUT WHITE MOTOR OUTPUT OF BLDC CN-COM CN-COM COMMUNICATION WHITE COMMUNICATION BETWEEN INDOOR AND OUTDOOR CN-LEV...
Disassembly of the parts 8. Disassembly of the parts Warning : Disconnect the unit from power supply before making any checks. Be sure the power switch is set to “OFF”. 1. To remove the Grille from the Chassis. - Push mark[ ] on the grille bottom then pull it down and remove 3 securing screws.
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Disassembly of the parts 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. - Remove the securing screws from the chassis. Top Cover Air Guide - Pull the pipe cover, top cover and the air guide.
Replacement Parts List 10. Replacement parts List LOCATION PART No DESCRIPTION REMARKS CRNN126SV*0 CRNN186SV*0 131410 CHASSIS ASSEMBLY 3141A20008A 135311-1 GRILLE ASSEMBLY, DISCHARGE(INDOOR) 3531A20124B 135311-2 GRILLE ASSEMBLY, DISCHARGE(INDOOR) 3531A20125B 135316 GRILLE ASSEMBLY, FRONT(INDOOR) BLUE 3531A10289A WOOD 3531A10153V METAL 3531A10153Z 135303-1 GRILLE, INLET BLUE 3530A10116B WOOD...
Functions 2. 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 Temperature. • Indoor fan is delayed for 5 seconds at the starting. Starting Current Control Time Delay Safety Control •...
Operation Dtails 3. Operation Details (1) The function of main control Time Delay safety Control • 30sec ... The 4-way valve is ceased for 30sec. to prevent the refrigerant-gas abnormal noise when the Heating operation is OFF or switched to the other operation mode while compress is off. While compressor is running, it takes 3~5 seconds to switch to another mode.
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Operation Dtails Heating Mode Operation The unit will operate according to the setting by the remote controller and the operation diagram is shown as following. Intake Air Temperature minimum 3min Setting Temperature +3°C (Compressor OFF) Setting Temperature (Compressor ON) minimum minimum 1min 10sec.
Wiring Diagrams 6. Wiring Diagrams (Transmission) CONNECTOR SPEC COLOR DESCRIPTION NUMBER CN-POWER AC POWER SUPPLY WHITE AC POWER LINE INPUT FOR INDOOR CONTROLLER CN-MOTOR AC FAN MOTOR OUTPUT YELLOW MOTOR OUTPUT OF PHASE CONTROL CN-D/PUMP DRAIN PUMP OUTPUT WHITE AC OUTPUT FOR DRAIN PUMP CN-COMM COMMUNICATION WHITE...
Function 2. Function Scroll compressor that operates on 30~120Hz by inverter drive enables Inverter Compressor capacity control. The oil separator is a device that collects the discharged oil from the Oil separator Compressor. The collected oil is constantly recycled to the compressor via capillary tube.
Operation detail 3. Operation detail 3.1 CRUN458S0 Compressor Control (1) Compressor operation method - In order to stop the compressor, decrease the frequency to 30Hz, and turn off. - Rising speed of frequency : 1Hz/2seconds Decreasing speed of frequency: 1Hz/1second. (2) Compressor Operation Step - Maximum frequency for ICOFis limitted by the temperature of outdoor air.
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Operation detail Linear Expansion Valve(LEV) Control (1) Control type LEV for Indoor Unit for Outdoor Unit On state Off state Thermo off state Indoor unit Indoor unit indoor unit At starting Feed back Feed back control control At starting Feed back Freed back Feed back control...
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Operation detail Control of Outdoor Unit Fan (1) Outdoor unit fan is controlled by motor which can be rotated high/low speed (2) Steps of outdoor unit fan speed : 4 Steps Step_Fan Left Right High High High (3) Determination of fan speed(Step_Fan) Step_Fan Step_Fan ∑Qj...
Operation detail Oil Return Operation (1) Conditions for oil return operation 1. Compressor on time (normal operation not full capacity operation) is 6 hours or more. 2. During operation, deicing operation is started or the load is changed to full capacity operation, the cumulative time is reset (2) Process of oil return operation 1.
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Operation detail (3) Control the discharge temperature 1. At the temperature of compressor discharge pipe >100°C, turn on the liquid injection valve. Inverter compressor, Comp.: off 115°C Frequency: 10Hz down 110°C ICOF: keep up the frequency 100°C 95°C Comp.: normal operation ICOF: Inverter Compressor Operation Frequency (4) DC peak control 1.
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Operation detail 3.2 CRUN1008T0 Compressor Control (1) Compressor operation method - Capacity control operation with the combination of Inverter compressor and constant speed compressor - It is not allowed to operate constant speed compressor only. - In over capacity range, rising of frequency is restrained because of the heat exchanger capacity limit. Inverter comp.: 120Hz...
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Operation detail (4) starting Method - Total 7 minutes consumed for starting operation - After 7 minutes, the compressor operates at target frequency step • Stage A = Step 6(40Hz + Off) • Stage B = determined by pressure Consumed time 1 min 2 min 1 min...
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Operation detail Linear Expansion Valve(LEV) Control (1) Control type LEV for Indoor Unit for Outdoor Unit On state Off state Thermo off state Indoor unit Indoor unit indoor unit At starting Fully open Base Pulse Fully Closed Fully Closed Feed back Feed back Fully open Fully Closed...
Operation detail Control of Reversing Valve 1. Initial state: keep up OFF state 2. Cooling and Deicing operation: OFF Heating operation : ON 3. Change operation mode(Cooling Heating): 3minutes restarting, reversing valve ON. 4. Compressor stop because of Thermo-OFF: keep up the present state. Hot Gas Bypass Valve (1) General control 1.
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Operation detail (2) Control to prevent low pressure 1. If the measured pressure(transformed absolute pressure)from low-pressure sensor satisfies the condi- tion, take 1 minute periodic control like following graph. Cooling operation Heating operation Comp.: normal step Comp.: normal step Outdoor fan: normal Outdoor fan: normal Bypass valve: normal Bypass valve: normal...
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Operation detail (4) DC peak control 1. Criterion for DC peak : if the fault signal from IPM Intelligent (Power Module) is occurred continuously for 1.8ms, then it is judged that DC peak occurred. 2. After inverter compressor turned off, 3minutes later if there is no DC peak signal, then restart compres- sor.
Dimensional Drawings 4. Dimensional Drawings CRUN158S0 Liquid side 3-way valve Gas side 3-way valve Model CRUN458S0 Dimension 1225 1135 Service Manual 169...
Wiring Diagrams 6. Wiring diagrams CRUN458S0 Connector Connector SPEC Color Description SPEC Color Description Number Number POWER AC POWER SUPPLY CN13 DC-LINK DC LINK VOLTAGE DETECT FAN(L) FAN MOTOR LOW SIDE CN14 IPM CONTROL SIGNAL FAN(H) FAN MOTOR HIGH SIDE CN15 P-SEN(L) LOW PRESSURE SENSOR...
Wiring Diagrams Control board Connector Connector SPEC Color Description SPEC Color Description Number Number POWER 1(AC) AC POWER 1 CN16 LEV(B) LINEAR EXPANSION VALVE(B) CN17 MAGNETIC MAGNETIC SWITCH NOT USE TO-INDOOR TRANSMISSION WITH INDOOR CN18 FAN(L) FAN MOTOR (LEFT) JIG1, 2 JIG POWER CN19 FAN(R)
Control Device and Functions 1. Control Devices and Function 1.1 Wired Remote Control ............184 1.2 Wireless Remote Control ..........185 1.3 Simple Central Control............186 1.4 Group Control with wired Remote Control......192 2. Deluxe Central Control 2.1 Introduction................193 3. Installation 3.1 Transmission between indoor units and outdoor unit ..199 3.2 Addressing of indoor units..........201 3.3 Group number setting for indoor units......204 3.4 Optional operation.............207...
Control Devices 1. Control Devices and Function 1.1 Wired Remote Control 1.1.1 Appearance and Functions Appearance Functions (Button Descriptions) Ceiling Mounted Cassette Type: No. Name Function CRNN -TC/TD/TE Operation display Displays the operation conditions. Convertible Type: Operation starts when this button is pressed, and On/Off stops when the button is pressed again.
Control Devices 1.2 Wireless Remote Control 1.2.1 Appearance and Functions Appearance Functions (Button Descriptions) No. Name Function Mounted Type: CRNN -SR/ST Art Cool Type: CRNN -SP/SV/SU Operation starts when this button is pressed and START/STOP stops when the button is pressed again. OPERATION MODE Used to select the operation mode.
Control Devices 1.3 Simple Central Control 1.3.1 Features • Easy operation button. • Independent operation for 16 indoor units each. • Simultaneous turn ON/OFF for all of indoor units connected. • Easy change operation mode to cooling or heating • Set and clear lock-mode for each indoor unit •...
Control Devices 1.3.3 Electrical wiring PICTORIAL VIEW OF THE CONNECTION Outdoor unit Outdoor unit : SUB PCB MAIN PCB : TERMINAL BLOCK Control Box Earth Shield Line Control To Indoor unit JIG2 JIG1 MAIN PCB CENTRAL SUB PCB CONTROL UNIT To Indoor Units •...
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Control Devices 2 OR MORE SIMPLE CENTRAL CONTROL CONNECTION Indoor unit Indoor unit MAIN PCB <Group Number 0> Central To Indoor Master control DIP SWITCH Units Unit 1 Outdoor unit Outdoor unit The connection of Master and Slave : SUB PCB Indoor unit Indoor unit T.B : TERMINAL BLOCK...
Control Devices 1.3.5 Test run method 1. Set the wiring of system and indoor unit. 2. Apply power to the setting. 3. Do auto addressing to the outdoor unit. 4. After addressing then initialize the central controller(Check up Dip Swtich ON('1')). •...
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Control Devices INSTALLATION ORDER Remove upper & lower case. Fixate screw in the holes of the For Dip switch, and Rotary case bottom. switch setting, refer to the page “How to Install”. For wiring connection, refer page Adjust the upper case in accor- Check the operation by supply- “Installation Procedure”...
Control Devices . ROTARY SWITCH SETTING(INSTALLATION FOR 2 OR MORE SIMPLE CENTRAL CONTROL) The setting of Group Number in the Central Control is done by the rotary switch as shown in the figure below. It is possible to set 0~15 Group(Total 16 Groups). All the numbers on the rotary switch represent the different Group Numbers.
Control Devices 1.4 Group Control with Wired Remote Control It operates maximum 16 Units by only one Wired Remote Control, and each Unit starts sequentially to prevent overcurrent. Main PCB Indoor Unit 1 Indoor Unit 2 Indoor Unit 16 Terminal(Local Supply) Terminal(Local Supply) Terminal(Local Supply) Block...
Where needs from a new customer occur or where purchase of additional air conditioner is done, the Deluxe Central control can be smoothly installed. Outdoor Unit Indoor Indoor Indoor Deluxe Unit #1 Unit #2 Unit #3 Central control Indoor ……… Indoor Unit #240 Unit #256 Figure 1) Overview of LG MultiV Central Control System Service Manual 193...
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Deluxe Central Control 2.1.2 Major Characteristics Figure 2) Deluxe Central control 1. Individual/Integrated Operation/Monitoring You can identify operation status of the air conditioner, operation mode, wind quantity, wind direction, locking, temperature setting and error, etc by selecting the installed air conditioner through individual selection, group selection or all selection.
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Deluxe Central Control 6. Convenient GUI / Touch Screen Not requires special education for using the Deluxe Central control, conveniently used only by pressing the buttons on the screen, and its function can be understood with intuitive pictogram. Especially schedule setting is done by simply dragging the screen as patented technology differently from the existing system requiring to press the button by more than average 30 times to enter a schedule.
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Deluxe Central Control Figure 3) Deluxe Central control Table 1) Comparison Between Central control Characteristics Internet Central control PC Central control Deluxe Central control Dedicate PC Non-required Required Non-required Configuration User S/W User S/W, Engine S/W Main Body of Web Pad Deluxe Central control Position of program Download to i-GW...
Deluxe Central Control 2.1.3 Major Function of Deluxe Central control [ System Control ] To check general monitor function of the air con central control system such as selection of group and air conditioner, air conditioner control monitor function etc. [ System Monitor ] To check the current actual time status of the whole of air conditioner.
Deluxe Central Control 2.1.4 System Configuration Scenario 1 : In case of not using Internet access function Product B part A part Control System Multi-V Interface Delux Central Control PI485 PI485 Cross UTP Cable (Cross LAN Cable) RS-485 Cable PI485 PI485 Main Specifications 1.
Installation Installation 3. Installation 3.1 Transmission between indoor units and outdoor unit 1) Transmission cable • Types : shielding wire CVVS or CPEVS • Diameter : over 0.75mm • Insulation material : PVC • Maximum allowable temperature: 60°C • Maximum allowable line length: under 300m 2) Remote control cable •...
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Installation Example connection of transmission wire : 3 Phase power line Power supply switch (Switch/Fuse) : Single phase power line Power supply : Transmission line(2 wire) 3 phase 50Hz 380~415V Power supply 1 phase 50Hz 220~240V Outdoor Unit Control Box Central controller Indoor unit Vcc GND...
Installation 3.2 Addressing of indoor units • The address of indoor units would be set by Automatic addressing - CRUN1008T0 Press the switch(SW02M) of outdoor unit for 5 seconds 7-segment of Main PCB in outdoor unit : displays "88" 2~3 minutes passed after , the address of each indoor unit is displayed at each wired remote controller or display device of each indoor unit.
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Installation The procedure of automatic addressing(CRUN1008T0) Outdoor Unit...
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Installation The procedure of automatic addressing(CRUN458S0) 1 minutes Stop pressing SW01M Service Manual 203...
Installation 3.3 Group number setting for indoor units 3.3.1 Process fot Group Number Setting Confirm the power of whole system(indoor unit, outdoor unit) is OFF, otherwise turn off. The transmission lines connected to C, D of simple central controller should be connected to C,D terminal port for central control of outdoor unit with care for their polarity (C C, D DC power line(12V) and ground line should be connected to terminal block of adjacent indoor unit...
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Installation Wiring Diagram for Simple Central Control Outdoor Unit 1 Control box Control Board < Group Number 0 > Central Control Master Unit 1 SWITCH For Master the First switch of DIP switch should be ON and the other three switches can be On or Off (Don ’t Care Condition) The connection of Master and Slave Outdoor Unit 2 Control box...
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Installation Position of rotary switch on the indoor unit Cassette, Duct, Convertible type indoor unit Group ID rotary S/W Indoor unit ID rotary S/W Wall Mounted type indoor unit Group ID rotary S/W Indoor unit ID rotary S/W Artcool type indoor unit Group ID S/W Indoor unit ID rotary S/W Outdoor Unit...
Installation 3.4 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. •...
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Installation 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...
The phenomena from main component failure 1. The phenomena from main component failure The phenomena from main component failure Component Phenomenon Cause Check method and Trouble shooting Not operating Motor insulation broken Check resistance between terminals and chassis Strainer locking Service necessary Oil shortage Open drain cock and check oil...
Checking Method for Key Components 2. Checking Method for Key Fompornents 2.1 Compressor Caution Turn-off the main power of the indoor/outdoor unit before check Cheking Method 1 Check the compressor 1. Check an electric leakang with DC 500V megger Comp. pipe Uncover the compressor terminal cover, and then unplug compressor power cable from the terminal.
Checking Method for Key Components 2.2 Linear Empansion Valve DC 12V Driving circuit ø5 ø4 ø4 White ø3 ø3 Yellow Orange ø2 ø2 Blue ø1 ø1 • Pulse signal output value and valve operation Output state Output(ø) No. ø1 ø2 ø3 ø4 •...
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Checking Method for Key Components • LEV Coil and body(Outdoor unit) Coil part Body Lead wire • Remove and assemble the coil Remove Assemble • Grip the A part tightly, and pull up coil part upward. When the coil part is removed or assembled, be careful not to bend the pipe of the body.
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Checking Method for Key Components • LEV failure check method * Attention: Outdoor unit LEV and Indoor unit LEV are different in specification, so the repair process may be different Failure mode Diagnosis Repair process Unit Microcomputer 1.Disconnect the LEV connector form control board and Check and replace Indoor Driving circuit...
Checking Method for Key Components 2.3 3Phase Bridge Diode Internal circuit diagram Appearance 1. Unplug the + terminal of electrolytic capacitor from the + terminal of 3phase bridge diode 2. Set the multi meter to resistance mode Check and estimate the resistance between each pair of terminal (+, -), (+, ~(U)), (+, ~(V)), (+, ~(W)), (~(U), -), (~(V), -), (~(W), -), the estimated value should be large enough to Mega Ohm unit.
Checking Method for Key Components 2.4 IPM(Integrated Power Module) Internal circuit diagram Appearance Array of IPM Pin 1. Unplug the +, – terminal of electrolytic capacitor from the P and N terminal of 2. Set the multi meter to resistance mode Check and estimate the resistance between each pair of terminal (P, N), (P, U), (P, V), (P, W), (U, N), (V, N), (W, N), the estimated value should be large enough to Mega Ohm unit.
Checking Method for Key Components 2.5 Other Electrolytic capacitor and resistor for voltage distribution Guide of check electrolytic capacitor and resistor for voltage distribution 1) Disconnect an terminal of voltage distribution resistor from each DC link electrolytic capacitor 2) Set the multi meter to resistance mode, connect the probe to +,- terminal of the capacitor.
Self-diagnosis function 3. Self-diagnosis function Error Indicator • The function is to self-diagnose airconditioner and indicate the problems, if any. • Error mark is displayed on display window of indoor units and wired remote controller, and 7-segment LED of outdoor unit control board as shown in the table. •...
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Self-diagnosis function Error code 52, 53, 54, 56, 57 are applied only to CRUN1008T0 Display Title Cause of Error CT sensor CT sensor open or short Inverter compressor discharge pipe Inverter compressor dischare pipe sensor open or sensor (discharge temperature) short Low pressure sensor open or short Low pressure sensor...
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Self-diagnosis function Fault diagnosis and Trouble shooting guide Display Title Meaning Cause of error code Indoor unit sensor(air) It is occurred that the • The temperature sensor unplugged Indoor unit sensor temperature sensor may • The sensor may be open or short (inlet pipe) detect abnormal value •...
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Self-diagnosis function Fault diagnosis and Trouble shooting guide Display Title Meaning Cause of error code In the case that indoor unit • Wired remote controller PCB may be Wired remote controller can not receive any signal poor indoor unit transmission from wired remote controller •...
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Self-diagnosis function Fault diagnosis and Trouble shooting guide Display Title Meaning Cause of error code • Malfunction of float switch of drain Although operation signal of pump Fault of drain pump drain pump is occurred, the • Malfunction of drain pump float switch send full signal •...
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Self-diagnosis function Fault diagnosis and Trouble shooting guide Display Title Meaning Cause of error code • Automatic addressing problem. • Unplugging of transmission connector Outdoor unit In the case that indoor unit • Misconnection or open of transmission cable can not receive any signal indoor unit •...
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Self-diagnosis function Fault diagnosis and Trouble shooting guide Display Title Cause of error Meaning code • Example: When one or more indoor units are All indoor units are not Different operated in cooling mode, if an indoor unit which is operating in the same mode.
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Self-diagnosis function Fault diagnosis and Trouble shooting guide Display Title Meaning Cause of error code • An instant over current in the U,V,W phase of The protection operation of compressor inverter compressor driving • Overheat of IPM for malfunction of heat radiation DC Peak device(IPM) for over •...
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Self-diagnosis function Fault diagnosis and Trouble shooting guide Display Title Meaning Cause of error code • Malfunction of compressor When current detection is • Blocking of pipe Max CT over the maximum current • Malfunction of current detection circuit limit •...
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Self-diagnosis function Fault diagnosis and Trouble shooting guide Display Title Meaning Cause of error code • Poor connection on DC link terminal DC charging is not • Malfunction of starting relay performed for 45 sec. after • Malfunction of capacitor DC link starting relay turn on (initial •...
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Self-diagnosis function Fault diagnosis and Trouble shooting guide Display Title Meaning Cause of error code • Malfunction of high pressure switch Compressor off has occurred • Fan lock of indoor or outdoor unit High pressure 3 times in1 hour • Obstacles of indoor or outdoor heat exchanger •...
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Self-diagnosis function Fault diagnosis and Trouble shooting guide Display Title Meaning Cause of error code Input voltage is out of Low / over • Abnormal of Input power voltage tolerance of rating voltage voltage • Malfunction of circuit for detection of voltage Trouble shooting Flow Is normal input voltage? Check power supply system...
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Self-diagnosis function Fault diagnosis and Trouble shooting guide Display Title Meaning Cause of error code • Abnormal of sensor for detecting temperature of Due to over rising of Discharge discharge gas from compressor inverter compressor temperature • Malfunction of circuit for detection of temperature discharge temperature, (inverter of discharge gas from compressor...
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Self-diagnosis function Fault diagnosis and Trouble shooting guide Display Title Meaning Cause of error code • Abnormal of sensor for detecting temperature of Discharge Due to over rising of discharge gas from compressor temperature constant speed compressor • Malfunction of circuit for detection of temperature (constant discharge temperature, of discharge gas from compressor...
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Self-diagnosis function Fault diagnosis and Trouble shooting guide Display Title Meaning Cause of error code Due to high pressure, Compressor off has occurred • Malfunction of high pressure sensor 3 times in1 hour • Fan lock of indoor or outdoor unit High pressure •...
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Self-diagnosis function Fault diagnosis and Trouble shooting guide Display Title Meaning Cause of error code • Abnormal of sensor for detecting pressure of Compressor off has occurred suction pipe of compressor 3 times in1 hour • Malfunction of circuit for detecting pressure of Low pressure suction pipe of compressor The suction pressure of...
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Self-diagnosis function Fault diagnosis and Trouble shooting guide Display Title Meaning Cause of error code 40, 41, •The temperature sensor is unplugged 42, 43, •The sensor is open or short by its inferiority Sensor Sensor detects abnormal 44, 45, •PCB inferiority error value 46, 47,...
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Self-diagnosis function Fault diagnosis and Trouble shooting guide Display Title Meaning Cause of error code The total capacity of indoor units being connected is Indoor over rated capacity of • Over connection to outdoor unit capacity connection outdoor unit by 130% (10HP), •...
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Self-diagnosis function Fault diagnosis and Trouble shooting guide Display Title Meaning Cause of error code Transmission In the case that main PCB error from • The connector for transmission disconnected can not receive any signal inverter PCB to • The transmission line is misconnected or shorted from inverter PCB main PCB in •...
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Self-diagnosis function Fault diagnosis and Trouble shooting guide Display Title Meaning Cause of error code Transmission • The connector for transmission disconnected error from In the case that main PCB • The transmission line is misconnected or shorted indoor unit to can not receive any signal •...
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Self-diagnosis function Fault diagnosis and Trouble shooting guide Display Title Meaning Cause of error code Reverse • Inverter PCB is abnormal connection of • One of the R,S,T line is disconnected R,S,T power • Connection order of R,S,T line is changed line Trouble shooting Flow Is the R,S,T power...
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Self-diagnosis function Fault diagnosis and Trouble shooting guide Display Title Meaning Cause of error code Transmission • Group setting is not carried out In the case that main PCB error from • Transmission connector unplugged can not receive any signal central •...
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Self-diagnosis function Fault diagnosis and Trouble shooting guide Display Title Meaning Cause of error code • Group setting is not carried out Transmission In the case that central • Transmission connector unplugged error from main controller can not receive • Transmission cable misconnected / disconnection PCB in the any signal •...
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Self-diagnosis function Fault diagnosis and Trouble shooting guide Display Title Meaning Cause of error code In the case that inverter Transmission PCB can not receive any • The connector for transmission disconnected error from main signal • The transmission line is misconnected or shorted PCB to inverter from main PCB •...