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SPLIT TYPE ROOM AIR CONDITIONER SLIM DUCT type INVERTER SERVICE INSTRUCTION Models Indoor unit Outdoor unit AOU9RLFC ARU9RLF AOU12RLFC ARU12RLF ARU18RLF AOU18RLFC 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 4°F(2°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 6°F(3°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.
6. OUTDOOR FAN CONTROL 1. Outdoor Fan Motor 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 AOU9 / 12 / 18RLFC 2.
7. COMPRESSOR CONTROL 1. OPEARTION 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 / Dry Heating Minimum Maximum Minimum Maximum AOU9RLFC 10rps 74rps...
8. TIMER OPEARTION CONTROL 8-1 WIRELESS REMOTE CONTROLLER (OPTION) The Table 12 shows the available timer setting based on the product model. ( Table 12 : Timer Setting ) ON TIMER / OFF TIMER PROGRAM TIMER SLEEP TIMER ARU9/ 12/ 18RLF 1.
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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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8-2 WIRED REMOTE CONTROLLER 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 ARU9/ 12/ 18RLF 1. ON / OFF TIMER OFF timer : When the clock reaches the set time, the air conditioner will be turned off.
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2-2. DAY OFF setting The DAY OFF setting is only available for days for which weekly settings already exist. If the operating time carries over to the next day (during a next day setting), the effective DAY OFF range will be set as shown below. Normal DAY OFF Operation mode...
9. 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. ( Table 14 : The pulse range of the electronic expansion valve control ) Operation mode Pulse range...
13. 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. (Table 15 : Operation contents memorized when the power is interrupted) Wired remote controller Wired remote controller Wireless remote...
17. ECONOMY OPERATION The ECONOMY operation functions by pressing ECONOMY button on the remote controller. At the maximum output, ECONOMY Operation is approximately 70% of normal air conditioner operation for cooling and heating. The ECONOMY operation is almost the same operation as below settings. ( Table 18 ) Mode Cooling/ Dry...
20. DRAIN PUMP OPERATION During Cooling / Dry mode 1. When the compressor starts, the drain pump starts simultaneously. 2. The drain pump operates continuously for 3 minutes after the compressor is turned off. 3. When the compressor stops by the "Anti- freezing protection", the drain pump is turned off in 1 hour after the compressor stops.
21. 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 25 minutes ( More than 25 minutes ( 9/ 12RLFC 9/ 12RLFC...
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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)< Intermittent operation Continuous operation Outside air temp.
22. OFF DEFROST OPEARTION 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.
23. VARIOUS PROTECTIONS 1. DISCHARGE GAS TEMPERATURE OVERRISE PREVENTION 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 23 : Anti-freezing Protection Operation / Release Temperature) Outdoor temperature Temperature...
2-1 ERROR DISPLAY 2-1-1 WIRED REMOTE CONTROLLER DISPLAY 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 MO TU WE TH FR SA ex.
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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. Self-diagnosis check 2.
2-2 TROUBLE SHOOTING WITH ERROR CODE Trouble shooting 1-1 Indicate or Display: OUTDOOR UNIT Error Method: Refer to error code table. Serial communication error (Serial Reverse Transfer Error) Detective details: Detective Actuators: When the indoor unit cannot receive the serial signal from Outdoor unit Outdoor unit Main PCB more than 2minutes after power ON, or the indoor unit cannot receive Outdoor unit fan motor...
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Trouble shooting 1-2 Indicate or Display: INDOOR UNIT Error Method: Refer to error code table. Serial communication error (Serial Forward Transfer Error) Detective details: Detective Actuators: When the outdoor unit cannot receive the serial signal from Indoor unit Indoor unit Controller PCB more than 10seconds.
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Trouble shooting 2 Indicate or Display: INDOOR UNIT Error Method: Wired remote controller Refer to error code table. communication error Detective details: Detective Actuators: When the indoor unit cannot receive the signal from Wired Remote Control Indoor unit Controller PCB more than 1minute during normal operation.
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Trouble shooting 3 Indicate or Display: INDOOR UNIT Error Method: Refer to error code table. Indoor unit model information error EEPROM access abnormal Detective details: Detective Actuators: When power is on and there is some below case. Indoor unit Controller PCB 1.
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Trouble shooting 4 Indicate or Display: INDOOR UNIT Error Method: INDOOR UNIT Refer to error code table. Manual auto switch error Detective Actuators: Detective details: Indoor unit Controller PCB When the Manual Auto Switch becomes ON for consecutive 60 or more seconds.
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Indicate or Display: Trouble shooting 5 INDOOR UNIT Error Method: INDOOR UNIT Refer to error code table. Indoor room thermistor error Detective details: Detective Actuators: Indoor unit Controller PCB When Room Temperature Thermistor open or short-circuit is detected. Room temperature thermistor Forecast of Cause : 1.
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Trouble shooting 6 Indicate or Display: INDOOR UNIT Error Method: INDOOR UNIT Refer to error code table. Indoor heat Ex.(Pipe) thermistor error Detective Actuators: Detective details: Indoor unit Controller PCB When Heat Ex. Temperature Thermistor open or short-circuit is detected. Heat Ex.
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Trouble shooting 7 Indicate or Display: INDOOR UNIT Error Method: Refer to error code table. Indoor unit fan motor error Detective Actuators: Detective details: Indoor unit Controller PCB When the condition that actual frequency of Indoor Fan is below 1/3 of target frequency is continued more than 56 seconds. Indoor unit Fan motor Forecast of Cause: 1.
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Indicate or Display: Trouble shooting 8 INDOOR UNIT Error Method: Refer to error code table. Drain pump error Detective Actuators: Detective details: Indoor unit Controller PCB When Float switch is ON for more than 3 minutes. Float switch Forecast of Cause : 1. Float switch failure 2.
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Trouble shooting 9 Indicate or Display: OUTDOOR UNIT Error Method: Refer to error code table. Outdoor unit main PCB error Detective details: Detective Actuators: Access to EEPROM failed due to some cause after outdoor unit started. Outdoor unit Main PCB Forecast of Cause: 1.
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For AOU9 / 12RLFC Trouble shooting 10-1 Indicate or Display: OUTDOOR UNIT Error Method: INDOOR UNIT Refer to error code table. PFC circuit error Detective Actuators: Detective details: When inverter output DC voltage is higher than 415V for over 3 seconds, Outdoor unit Main PCB the compressor stops.
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For AOU18RLFC Indicate or Display: Trouble shooting 10-2 OUTDOOR UNIT Error Method: INDOOR UNIT Refer to error code table. Active filter error Detective Actuators: Detective details: Outdoor unit Main PCB When inverter input DC voltage is higher than 425V or Active filter module lower than 80V.
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Trouble shooting 11 Indicate or Display: OUTDOOR UNIT Error Method: Refer to error code table. IPM error Detective Actuators: Detective details: When more than normal operating current to IPM in Main PCB flows, Outdoor unit Main PCB the compressor stops. Outdoor unit Transistor PCB (18RLFC) After the compressor restarts, if the same operation is repeated within 40sec, Compressor...
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Trouble shooting 12 Indicate or Display: OUTDOOR UNIT Error Method: INDOOR UNIT Refer to error code table. Discharge thermistor error Detective details: Detective Actuators: When Discharge pipe temperature thermistor open or short-circuit Outdoor unit Main PCB is detected at power ON or while running the compressor. Discharge pipe temperature thermistor Forecast of Cause : 1.
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Trouble shooting 13 Indicate or Display: OUTDOOR UNIT Error Method: Refer to error code table. Heat Ex.(Pipe) thermistor error Detective details: Detective Actuators: Outdoor unit Main PCB When Heat exchanger temperature thermistor open or Heat exchanger thermistor short-circuit is detected at power ON or while running the compressor. Forecast of Cause : 1.
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Trouble shooting 14 Indicate or Display: OUTDOOR UNIT Error Method: Refer to error code table. Outdoor thermistor error Detective details: Detective Actuators: Outdoor unit Main PCB When Outdoor temperature thermistor open or short-circuit is Outdoor thermistor detected at power ON or while running the compressor. Forecast of Cause : 1.
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Trouble shooting 15 Indicate or Display: OUTDOOR UNIT Error Method: Refer to error code table. Current sensor error Detective details: Detective Actuators: When Input Current Sensor has detected 0A, while Inverter Compressor is Outdoor unit Main PCB operating at higher than 56rps, after 1minute upon starting the Compressor. (Except during the defrost operation) Forecast of Cause : 1.
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Trouble shooting 16 Indicate or Display: OUTDOOR UNIT Error Method: Refer to error code table. Over current error Detective details: Detective Actuators: "Protection stop by overcurrent generation after inverter compressor start Outdoor unit Main PCB processing completed'' generated consecutively 10 times. Compressor * The number of generations is reset if the start-up of the compressor succeeds.
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Trouble shooting 17 Indicate or Display: OUTDOOR UNIT Error Method: Refer to error code table. Compressor control error Detective details: Detective Actuators: If the detected rotor location is out of phase with actual rotor location Outdoor unit Main PCB more than 90°, the compressor stops. Compressor After the compressor restarts, if the same operation is repeated within 40sec, the compressor stops again.
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Trouble shooting 18 Indicate or Display: OUTDOOR UNIT Error Method: Refer to error code table. Outdoor unit fan motor error Detective Actuators: Detective details: When outdoor fan rotation speed is less than 100rpm in 20 seconds Outdoor unit Main PCB after fan motor starts, fan motor stops.
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Trouble shooting 19 Indicate or Display: OUTDOOR UNIT Error Method: Refer to error code table. 4-way valve error Detective Actuators: Detective details: Indoor unit Controller PCB When the indoor heat exchanger temperature is compared with the room temperature, and either following condition is detected Heat Ex.
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Trouble shooting 20 Indicate or Display: OUTDOOR UNIT Error Method: INDOOR UNIT Discharge temperature error Refer to error code table. Detective details: Detective Actuators: "Protection stop by "discharge temperature 230°F(110°C) during Outdoor unit Main PCB Discharge temperature thermistor compressor operation"" generated 2 times within 24 hours. Forecast of Cause : 1.
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?
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) AOU9/ 12/ 18RLFC 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 (CN40 or CN700) ( Loose connector or open cable ) EXPANSION CN40 VALVE COIL [9/12RLFC] BLUE ORANGE YELLOW CN700 WHITE [18RLFC]...
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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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For AOU18RLFC 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 Terminal Resistance value Tester(+) Tester(-) (+IN)
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For AOU18RLFC SERVICE PARTS INFORMATION 7 Mounted on Transistor PCB) Check Point 1 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. TM301 (P) - TM305(U) / TM304(V) / TM303(W) TM302 (N) - TM305(U) / TM304(V) / TM303(W) Judge the result of...
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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1-3. Setting the Cooler room temperature correction Depending on the installed environment, the room temperature sensor may require a correction. The settings may be selected as shown in the table below. Factory setting) Setting Description Function Number Setting Value Standard Slightly lower control Lower control Warmar control...
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1-6. Setting the Indoor room temperature sensor switching function (Only for Wired remote controller) The following settings are needed when use the control by Wired remote controller temperature sensor. Factory setting) Setting Description Function Number Setting Value If setting value is “00”, room temperature is controlled by the indoor unit temperature sensor.
3-1-2 PROCEDURES TO CHANGE THE FUNCTION SETTING The function settings of the control of the indoor unit can be changed by this procedure 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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FUNCTION SETTING METHOD (for Wireless remote controller) Entering the Function Setting Mode While pressing the FAN button and SET TEMP.( ) button simultaneously, press the RESET button to enter the function setting mode. MIN. STEP 1. Setting the Remote controller Signal Code Use the following steps to select the signal code of the remote controller.
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REMOTE CONTROLLER SIGNAL CODE SETTING Use the following steps to select the signal code of the remote controller. (Note that the air conditioner cannot receive a signal code if the air conditioner has not been set for the signal code.) (1) Press the START/STOP button until only the clock is displayed on the remote controller display.