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SPLIT TYPE ROOM AIR CONDITIONER WALL MOUNTED type INVERTER SERVICE INSTRUCTION Models Indoor unit Outdoor unit AOU18RLB ASU18RLB AOU24RLB ASU24RLB R410A...
1. COOLING OPERATION A sensor (room temperature thermistor) built in the indoor unit body will usually perceive difference or variation between a set temperature and present room temperature, and controls the operation frequency of the compressor. * If the room temperature is 7°F(3.5°C) higher than a set temperature, the compressor operation frequency will attain to maximum performance.
2. HEATING OPERATION A sensor (room temperature thermistor) built in the indoor unit body will usually perceive difference or variation between a set temperature and present room temperature, and controls the operation frequency of the compressor. * If the room temperature is lower by 9°F(4.5°C) than a set temperature, the compressor operation frequency will attain to maximum performance.
4. AUTO CHANGEOVER OPERATION When the air conditioner is set to the AUTO mode by remote control, operation starts in the optimum mode from among the HEATING, COOLING, DRY and MONITORING modes. During operation, the optimum mode is automatically switched in accordance with temperature changes. The temperature can be set between 64°F(18°C) and 88°F(30°C) in 2°F(1°C) steps.
5. INDOOR FAN CONTROL 1. Fan speed ( Table 5 : Indoor fan speed ) Speed (rpm) Operation mode Air flow mode ASU18RLB ASU24RLB Heating 1260 1430 1120 1320 1020 1220 1020 Quiet Cool air prevention S-Lo 1260 1480 Cooling/ Fan...
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Indoor fan Setting air flow Indoor fan (as shown in Table 6) S-Lo (sec) ( Table 6 : Indoor fan speed ) Cooling X zone J zone Y zone ASU18RLB 770rpm 720rpm 270rpm 770rpm ASU24RLB 900rpm 850rpm 270rpm 900rpm 01-05...
6. OUTDOOR FAN CONTROL 1. Outdoor Fan Motor The Table 7 shows the type of the outdoor fan motor. The control method is different between AC motor and DC motor. ( Table 7 : Type of motor ) AC Motor DC Motor AOU18RLB AOU24RLB...
7. LOUVER CONTROL 1. VERTICAL LOUVER CONTROL (Function Range) ( Fig. 9 : Virtical air direction range ) Each time the button is pressed, the air direction range will change as follow: Cooling / Heating / Dry / Fan mode ①...
8. COMPRESSOR CONTROL 1. OPERATION FREQUENCY RANGE The operation frequency of the compressor is different based on the operation mode as shown in the Table 10 . ( Table 10 : Compressor frequency range ) Cooling Heating Minimum Maximum Minimum Maximum Minimum Maximum...
( Table 12 : Timer setting ) ON TIMER / OFF TIMER PROGRAM TIMER SLEEP TIMER ASU18RLB ASU24RLB 1. ON TIMER / OFF TIMER OFF timer : When the clock reaches the set time, the air conditioner will be turned off.
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3. SLEEP TIMER If the sleep is set, the room temperature is monitored and the operation is stopped automatically. If the operation mode or the set temperature is change after the sleep timer is set, the operation is continued according to the changed setting of the sleep timer from that time ON. In the cooling operation mode When the sleep timer is set, the setting temperature is increased 2°F(1°C).
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The Table 13 shows the available timer setting based on the product model. ( Table 13 : Timer setting ) ON TIMER / OFF TIMER WEEKLY TIMER TEMPERATURE SET BACK TIMER ASU18RLB ASU24RLB ON TIMER / OFF TIMER Same to 9-1 1.ON TIMER / OFF TIMER and shown in those.
10. ELECTRONIC EXPANSION VALVE CONTROL The most proper opening of the electronic expansion valve is calculated and controlled under the present operating condition based on the Table 14 . The compressor frequency, the detected temperature by the discharge temperature sensor, the indoor heat exchanger sensor, the outdoor heat exchanger sensor, and the outdoor temperature sensor.
14. AUTO RESTART When the power was interrupted by a power failure, etc. during operation, the operation contents at that time are memorized and when power is recovered, operation is automatically started with the memorized operation contents. When the power is interrupted and recovered during timer operation, since the timer operation time is shifted by the time the power was interrupted, an alarm is given by blinking (7 sec ON/2 sec OFF) the indoor unit body timer lamp.
17. COMPRESSOR PREHEATING When the outdoor heat exchanger temperature is lower than 41°F(5°C) and the all operation has been stopped for 30 minutes, power is applied to the compressor and the compressor is heated. (By heating the compressor, warm air is quickly discharged when operation is started.) When operation was started, and when the outdoor heat exchanger temperature rises to 44.6°F(7°C) or greater, preheating is ended.
20. HEAT INSULATION CONDITION ( BUILDING INSULATION ) This setting can make the room temperature control more suitable for homes or buildings with high insulation (Function Number 95). When the thermo sensor is turned ON it controls the compressor frequency at initial start to prevent overshoot in heating or cooling.
23. DEFROST OPERATION CONTROL 1. CONDITION OF STARTING THE DEFROST OPERATION The defrost operation starts as shown in the following Table 19 . ( Table 19 : Condition of starting defrost operation ) Compressor integrating operation time Normal defrost Less than 40 minutes ( More than 40 minutes ( AOU18RLB AOU18RLB...
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3. Defrost Flow Chart The defrosting shall proceed by the integrating operation time, outdoor temperature and outdoor heat exchanger temperature as follows. Heating operation start : Compressor ON (Not defrosted for 10 minutes) Normal defrost Integrating defrost -4°F (-20°C)< Outside air temp. Intermittent operation Continuous operation Outside air temp.
24. OFF DEFROST OPERATION CONTROL When operation stops in the [Heating operation] mode, if frost is adhered to the outdoor unit heat exchanger, the defrost operation will proceed automatically. In this time, if indoor unit operation lamp flashes slowly (7 sec ON / 2 sec OFF), the outdoor unit will allow the heat exchanger to defrost, and then stop.
25. VARIOUS PROTECTIONS 1. DISCHARGE GAS TEMPERATURE OVERRISE PREVENSION CONTROL The discharge gas thermosensor (discharge thermistor : Outdoor side) will detect discharge gas temperature. When the discharge temperature becomes higher than Temperature , the compressor frequency is decreased 20rps, and it continues to decrease the frequency for 20rps every 120 seconds until the temperature becomes lower than Temperature .
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3. ANTIFREEZING CONTROL (Cooling and Dry mode) The compressor frequency is decrease on cooling & dry mode when the indoor heat exchanger temperature sensor detects the temperature lower than Temperature . Then, the anti-freezing control is released when it becomes higher than Temperature . ( Table 24 : Anti-freezing protection operation / Release temperature ) Outdoor temperature Temperature...
2-1 ERROR DISPLAY 2-1-1 INDOOR UNIT AND WIRED REMOTE CONTROLLER DISPLAY Please refer the flashing pattern as follows. Indoor Unit : ASU18 / 24RLB The OPERATION, TIMER and ECONOMY lamps operate as follows according to the error contents. Indoor Unit Display Wired Remote Trouble Controller...
2-1-2 WIRED REMOTE CONTROLLER DISPLAY ( OPTION ) 1. SELF - DIAGNOSIS When " Er " in Temperature Display is displayed, inspection of the air conditioning system is necessary. Please consult authorized service personnel. Unit number (usually 0) Error code SU MOTU WETH FR SA ex.
2-2 TROUBLE SHOOTING WITH ERROR CODE Trouble shooting 1-1 Indicate or Display: OUTDOOR UNIT Error Method: Outdoor Unit : No indication Indoor Unit : Operation lamp: 1 time Flash, Timer lamp: 1 time Flash Serial Communication Error Economy lamp: Continuous flash. (Serial Reverse Transfer Error) ERROR CODE : [E : 11] Detective details:...
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Trouble shooting 1-2 Indicate or Display: INDOOR UNIT Error Method: Outdoor Unit : No indication Indoor Unit : Operation lamp: 1 time Flash, Timer lamp: 1 time Flash Serial Communication Error Economy lamp: Continuous flash. (Serial Forward Transfer Error) ERROR CODE : [E : 11] Detective details: Detective Actuators: When the outdoor unit cannot receive the serial signal from Indoor unit...
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Trouble shooting 2 Indicate or Display: INDOOR UNIT Error Method: Outdoor Unit : No indication Indoor Unit : Operation lamp: 1 time Flash, Timer lamp: 2 time Flash Wired Remote Controller Economy lamp: Continuous flash. Communication Error ERROR CODE : [E : 12] Detective details: Detective Actuators: When the indoor unit cannot receive the signal from Wired Remote Control...
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Trouble shooting 3 Indicate or Display: INDOOR UNIT Error Method: Outdoor Unit : No indication Indoor Unit : Operation lamp: 3 time Flash, Timer lamp: 2 time Flash Indoor Unit Model Information Error Economy lamp: Continuous flash. EEPROM Access Abnormal ERROR CODE : [E : 32] Detective details: Detective Actuators:...
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Trouble shooting 4 Indicate or Display: INDOOR UNIT Error Method: Outdoor Unit : No indication Indoor Unit : Operation lamp: 3 time Flash, Timer lamp: 5 time Flash Manual Auto Switch Error Economy lamp: Continuous flash. ERROR CODE : [E : 35] Detective Actuators: Detective details: Indoor unit Controller PCB...
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Indicate or Display: Trouble shooting 5 Outdoor Unit : No indication INDOOR UNIT Error Method: Indoor Unit : Operation lamp: 4 time Flash, Timer lamp: 1 time Flash Indoor Room Thermistor Error Economy lamp: Continuous flash. ERROR CODE : [E : 41] Detective details: Detective Actuators: Indoor unit Controller PCB...
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Trouble shooting 6 Indicate or Display: INDOOR UNIT Error Method: Outdoor Unit : No indication Indoor Unit : Operation lamp: 4 time Flash, Timer lamp: 2 time Flash Indoor Heat Ex.(Pipe) Economy lamp: Continuous flash. Thermistor Error ERROR CODE : [E : 42] Detective Actuators: Detective details: Indoor unit Controller PCB...
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Trouble shooting 7 Indicate or Display: INDOOR UNIT Error Method: Outdoor Unit : No indication Indoor Unit : Operation lamp: 5 time Flash, Timer lamp: 1 time Flash Indoor Unit Fan Motor Error Economy lamp: Continuous flash. ERROR CODE : [E : 51] Detective Actuators: Detective details: Indoor unit Controller PCB...
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Trouble shooting 8 Indicate or Display: INDOOR UNIT Error Method: Outdoor Unit : No indication Indoor Unit : Operation lamp: 5 time Flash, Timer lamp: 8 time Flash Intake Grille Error Economy lamp: Continuous flash. ERROR CODE : [E : 58] Detective details: Detective Actuators: Indoor unit Controller PCB...
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Trouble shooting 9 Indicate or Display: OUTDOOR UNIT Error Method: Outdoor Unit : No indication Indoor Unit : Operation lamp: 6 time Flash, Timer lamp: 2 time Flash Outdoor Unit Main PCB Error Economy lamp: Continuous flash. ERROR CODE : [E : 62] Detective details: Detective Actuators: Access to EEPROM failed due to some cause after outdoor unit started.
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Indicate or Display: Trouble shooting 10 Outdoor Unit : No indication OUTDOOR UNIT Error Method: Indoor Unit : Operation lamp: 6 time Flash, Timer lamp: 4 time Flash Active Filter Error Economy lamp: Continuous flash. ERROR CODE : [E : 64] Detective Actuators: Detective details: Outdoor unit Main PCB...
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Trouble shooting 11 Indicate or Display: OUTDOOR UNIT Error Method: Outdoor Unit : No indication Indoor Unit : Operation lamp: 6 time Flash, Timer lamp: 5 time Flash IPM Error Economy lamp: Continuous flash. ERROR CODE : [E : 65] Detective Actuators: Detective details: When more than normal operating current to IPM in Main PCB flows,...
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Trouble shooting 12 Indicate or Display: OUTDOOR UNIT Error Method: Outdoor Unit : No indication Indoor Unit : Operation lamp: 7 time Flash, Timer lamp: 1 time Flash Discharge Thermistor Error Economy lamp: Continuous flash. ERROR CODE : [E : 71] Detective details: Detective Actuators: When Discharge pipe temperature thermistor open or short-circuit...
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Trouble shooting 13 Indicate or Display: OUTDOOR UNIT Error Method: Outdoor Unit : No indication Indoor Unit : Operation lamp: 7 time Flash, Timer lamp: 3 time Flash Heat Ex.(Pipe) Thermistor Error Economy lamp: Continuous flash. ERROR CODE : [E : 73] Detective details: Detective Actuators: Outdoor unit Main PCB...
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Trouble shooting 14 Indicate or Display: OUTDOOR UNIT Error Method: Outdoor Unit : No indication Indoor Unit : Operation lamp: 7 time Flash, Timer lamp: 4 time Flash Outdoor Thermistor Error Economy lamp: Continuous flash. ERROR CODE : [E : 74] Detective details: Detective Actuators: Outdoor unit Main PCB...
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Trouble shooting 15 Indicate or Display: Outdoor Unit : No indication OUTDOOR UNIT Error Method: Indoor Unit : Operation lamp: 8 time Flash, Timer lamp: 4 time Flash Current Sensor Error Economy lamp: Continuous flash. ERROR CODE : [E : 84] Detective details: Detective Actuators: When Input Current Sensor has detected 0A, while Inverter Compressor is...
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Trouble shooting 16 Indicate or Display: OUTDOOR UNIT Error Method: Outdoor Unit : No indication Indoor Unit : Operation lamp: 9 time Flash, Timer lamp: 4 time Flash Trip Detection Economy lamp: Continuous flash. ERROR CODE : [E : 94] Detective details: Detective Actuators: "Protection stop by overcurrent generation after inverter compressor start...
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Trouble shooting 17 Indicate or Display: OUTDOOR UNIT Error Method: Outdoor Unit : No indication Indoor Unit : Operation lamp: 9 time Flash, Timer lamp: 5 time Flash Compressor Motor Control Error Economy lamp: Continuous flash. ERROR CODE : [E : 95] Detective details: Detective Actuators: If the detected rotor location is out of phase with actual rotor location...
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Trouble shooting 18 Indicate or Display: OUTDOOR UNIT Error Method: Outdoor Unit : No indication Indoor Unit : Operation lamp: 9 time Flash, Timer lamp: 7 time Flash Outdoor Unit Fan Motor Error Economy lamp: Continuous flash. ERROR CODE : [E : 97] Detective Actuators: Detective details: When outdoor fan rotation speed is less than 100rpm in 20 seconds...
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Trouble shooting 19 Indicate or Display: OUTDOOR UNIT Error Method: Outdoor Unit : No indication Indoor Unit : Operation lamp: 9 time Flash, Timer lamp: 9 time Flash 4 Way Valve Error Economy lamp: Continuous flash. ERROR CODE : [E : 99] Detective Actuators: Detective details: When the indoor heat exchanger temperature is compared with...
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Trouble shooting 20 Indicate or Display: OUTDOOR UNIT Error Method: Outdoor Unit : No indication Indoor Unit : Operation lamp: 10 time Flash, Timer lamp: 1 time Flash Discharge Temperature Error Economy lamp: Continuous flash. ERROR CODE : [E : A1] Detective details: Detective Actuators: "Protection stop by "discharge temperature...
2-3 TROUBLE SHOOTING WITH NO ERROR CODE Forecast of Cause: Trouble shooting 21 1. Power supply failure 2. External cause Indoor Unit - No Power 3. Electrical components defective Check Point 1 : Check Installation Condition Isn’t the breaker down? Check loose or removed connection cable.
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Forecast of Cause: Trouble shooting 22 1. Power supply failure 2. External cause Outdoor Unit - No Power 3. Electrical Components defective Check Point 1 : Check Installation Condition Isn’t the breaker down? Check loose or removed connection cable. >>If abnormal condition is found, correct it by referring to Installation Manual or Data &...
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Forecast of Cause: Trouble shooting 23 1. Setting/ Connection failure 2. External cause No Operation (Power is ON) 3. Electrical component defective Check Point 1 : Check indoor and outdoor installation condition Indoor Unit - Check incorrect wiring between Indoor Unit - Remote Control. Or, check if there is an open cable connection.
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Forecast of Cause: Trouble shooting 24 1. Indoor Unit error 2. Outdoor Unit error No Cooling / No Heating 3. Effect by surrounding environment 4. Connection pipe / Connection wire failure 5. Refrigeration cycle failure Check Point 1 : Check Indoor unit Does Indoor unit Fan run on High fan? Is Air filter dirty? Is Heat exchanger clogged?
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Forecast of Cause : Trouble shooting 25 1. Abnormal installation (Indoor/ Outdoor) Abnormal Noise 2. Fan failure (Indoor/ Outdoor) 3. Compressor failure (Outdoor) Diagnosis method when abnormal noise is occurred Abnormal noise is coming from Indoor unit. Abnormal noise is coming from Outdoor unit. (Check and correct followings) (Check and correct followings) Is Main unit installed in stable condition?
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Forecast of Cause Trouble shooting 27 1. House insulation setting has not been changed. 2. Temperature sensing location has not been changed. Too Warm 3. Installation location of the wired remote. 4. Function settings have not been changed. Check Point 1 : Check insulation level of structure Check Point 1-1 : Check Function Setting of house If insulation level is greater than R-13 set function 95 to 01.
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“Wired remote sensor” Check Point 3 : Check the remote controller display Check Point 3-1 : Check Function Setting Is function 42 (Indoor room temperature sensor Is the "Thermo Sensor Icon" displayed on the screen? switching function) set to 01? Ref.) Function Number Setting Va lue Setting Description...
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Forecast of Cause Trouble shooting 28 1. House insulation setting has not been changed. 2. Temperature sensing location has not been changed. Too Cool 3. Installation location of the wired remote. 4. Function settings have not been changed. Check Point 1-1 : Check Function Setting Check Point 1 : Check insulation level of structure of house If insulation level is greater than R-13 set function 95 to 01.
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“Wired remote sensor” Check Point 3-1 : Check Function Setting Check Point 3 : Check the remote controller display Is function 42 (Indoor room temperature sensor Is the "Thermo Sensor Icon" displayed on the screen? switching function) set to 01? Ref.) Function Number Setting Va lue Setting Description...
2-4 SERVICE PARTS INFORMATION SERVICE PARTS INFORMATION 1 Compressor Diagnosis method of Compressor ( If Outdoor Unit LED displays Error, refer to Trouble shooting ) Abnormal noise Stops soon after starting up Does not start up Check if vibration noise by Is there open or loose connection Is there open or loose connection loose bolt or contact noise...
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SERVICE PARTS INFORMATION 2 Compressor Check Point 1 : Check Connection Check terminal connection of Compressor (loose or incorrect wiring) Terminal cover opened (BLACK) (WHITE) (RED) AOU18/24RLB Check Point 2 : Check Winding Resistance Check winding resistance of each terminal If the resistance value is 0 or infinite, replace Compressor.
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SERVICE PARTS INFORMATION 3 Outdoor unit Electronic Expansion Valve ( EEV ) Check Point 1 : Check Connections Check connection of connector (CN700) ( Loose connector or open cable ) EXPANSION VALVE COIL BLUE ORANGE CN700 YELLOW WHITE Check Point 2 : Check Coil of EEV Check Point 3 : Check Voltage from Main PCB.
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SERVICE PARTS INFORMATION 4 Indoor unit fan motor Check Point 1 : Check rotation of Fan Rotate the fan by hand when operation is off. (Check if fan is caught, dropped off or locked motor) >>If Fan or Bearing is abnormal, replace it. Check Point 2 : Check resistance of Indoor Fan Motor Refer to below.
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SERVICE PARTS INFORMATION 6 Active filter module Check Point 1 : Check Open or Short-circuit and Diode (D1) Remove connector, check the open or short-circuit and the diode in the module Check the open or short-circuit Table.1 Each type standard value LOT No.
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SERVICE PARTS INFORMATION 7 Mounted on Transistor PCB) Check Point 1 : Check the Transistor of PCB ( for Resistance ) Disconnect the connection wires between the Transistor PCB - Capacitor PCB and Transistor PCB - Inverter Compressor. Set the tester to the "Resistance" mode, and measure the resistance between the following terminals.
3-1. FUNCTION SETTING 3-1-1 INDOOR UNIT Follow the instructions in the Local Setup Procedure, which is supplied with the remote control, in accordance with the installed condition. After the power is turned on, perform the Function Setting on the remote control. The settings may be selected between the following two: Function Number or Setting Value.
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1-4. Setting the Remote controller custom code (Only for wireless remote controller) The indoor unit custom code can be changed. Select the appropriate custom code. Factory setting) Function Number Setting Value Setting Description 1-5. Setting the External input control "Operation / Stop" mode or "Forced stop" mode can be selected. Factory setting) Function Number Setting Value...
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Temperature Correction When changing Function 95, perform this setting before other Room temp. control settings (Function 30, 31, 92, 93). If Function 95 is not set first, Room temperature control settings (Function 30, 31, 92, 93) will be reset and you must redo them again. 1-8.
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1-10. Setting the Room temperature control for wired remote controller sensor Depending on the installed environment, correction of the wire remote temperature sensor may be required. Select the appropriate control setting according to the installed environment. To change this setting, set Function 42 to Both "01". Ensure that the Thermo Sensor icon is displayed on the remote controller screen.
3-1-2 PROCEDURES TO CHANGE THE FUNCTION SETTING FOR WIRELESS RC This procedure changes to the function settings used to control the indoor unit according to the installation conditions. Incorrect settings can cause the indoor unit malfunction. After the power is turned on, perform the "FUNCTION SETTING" according to the installation conditions using the remote controller.
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Custom code setting for remote controller (1) Press the MODE button for more then 5 seconds. (2) Press the SET TEMP. ( ) buttons to change the signal code between Match the code on the display to the air conditioner signal code. (initially set to (3) Press the MODE button.