NO. 0302E RAK-50NH5/RAC-50NH5 SERVICE MANUAL REFER TO THE FOUNDATION MANUAL TECHNICAL INFORMATION CONTENTS FOR SERVICE PERSONNEL ONLY SPECIFICATIONS --------------------------------------------------------------5 HOW TO USE -------------------------------------------------------------------7 CONSTRUCTION AND DIMENSIONAL DIAGRAM ---------------- 30 MAIN PARTS COMPONENT --------------------------------------------- 32 WIRING DIAGRAM ----------------------------------------------------------- 35 CIRCUIT DIAGRAM ---------------------------------------------------------- 39...
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SAFETY DURING REPAIR WORK 1. In order to disassemble and repair the unit in question, be sure to disconnect the power cord plug from the power outlet before starting the work. 2. If it is necessary to replace any parts, they should be replaced with respective genuine parts for the unit, and the replacement must be effected in correct manner according to the instructions in the Service Manual of the unit.
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WORKING STANDARDS FOR PREVENTING BREAKAGE OF SEMICONDUCTORS 1. Scope The Standards provide for items to be generally observed in carrying and handling semiconductors in relative manufactures during maintenance and handling thereof. (They apply the same to handling of abnormal goods such as rejected goods being returned.) 2.
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(6) Use a three wire type soldering iron including a grounding wire. Metal plate (of Al. stainless steel, etc.) Working table Resistor 1MΩ (1/2W) Staple Earth wire Bare copper wire (for body earth) Fig. 3 Grounding of the working table Soldering iron Grounding wire Screw stop at the screwed...
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CAUTION In quiet operation or stopping the running, slight flowing noise of refrigerant in the refrigerating cycle is heard occasionally, but this noise is not abnormal for the operation. When it thunders near by, it is recommend to stop the operation and to disconnect the power cord plug from the power outlet for safety.
SPECIFICATIONS RAC-50NH5 RAK-50NH5 MODEL 40 W FAN MOTOR FAN MOTOR CAPACITOR FAN MOTOR PROTECTOR – JU1013D COMPRESSOR COMPRESSOR MOTOR CAPACITOR OVERLOAD PROTECTOR OVERHEAT PROTECTOR FUSE (for MICROPROCESSOR) 3.0A POWER RELAY POWER SWITCH TEMPORARY SWITCH SERVICE SWITCH TRANSFORMER VARISTOR 450NR NOISE SUPPRESSOR...
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Figure showing the Installation of Indoor and Outdoor unit. about 0.9m about 1.6m CAUTION Horizontally perpendicular to the unit Connection – 5 –...
SAFETY PRECAUTION Please read the “Safety Precaution” carefully before operating the unit to ensure correct usage of the unit. Pay special attention to signs of “ Warning” and “ Caution”. The “Warning” section contains matters which, if not observed strictly, may cause death or serious injury. The “Caution” section contains matters which may result in serious consequences if not observed properly.
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PRECAUTIONS DURING OPERATION The product shall be operated under the manufacturer specification and not for any other intended use. Do not attempt to operate the unit with wet hands, this could cause fatal accident. When operating the unit with burning equipments, regularly ventilate the room to avoid oxygen insufficiency.
MODEL NAME AND DIMENSIONS MODEL WIDTH (mm) HEIGHT (mm) DEPTH (mm) RAK-50NH5 MULTI-AIR CONDITIONER With this multi-air conditioner, several indoor units can be connected to one outdoor unit to be driven. You can operate the required number of indoor units. Combination of Operations:...
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INDOOR UNIT INDICATORS FILTER LAMP When the device is operated for a total of about 100 hours, the FILTER lamp lights to indicate that it is time to clean the filter. OPERATION LAMP This lamp lights during operation. TEMPORARY The OPERATION LAMP flashes in the following cases SWITCH during heating.
NAMES AND FUNCTIONS OF REMOTE CONTROL UNIT REMOTE CONTROLLER This controls the operation of the indoor unit. The range of control is about 7 meters. If indoor lighting is controlled electronically, the range of control may be shorter. This unit can be fixed on a wall using the fixture provided. Before fixing it, make sure the indoor unit can be controlled from the remote controller.
VARIOUS FUNCTIONS I Auto Restart Control If there is a power failure, operation will be automatically restarted when the power is resumed with previous operation mode and airflow direction. (As the operation is not stopped by remote controller.) If you intend not to continue the operation when the power is resumed, switch off the power supply. When you switch on the circuit breaker, the operation will be automatically restarted with previous operation mode and airflow direction.
HEATING OPERATION Use the device for heating when the outdoor temperature is under 21°C. When it is too warm (over 21°C), the heating function may not work in order to protect the device. In order to keep reliability of the device, please use this device above -15°C of the outdoor temperature. Press the FUNCTION selector so that the display indicates (HEAT).
DEHUMIDIFYING OPERATION Use the device for dehumidifying when the room temperature is over 16°C. When it is under 15°C, the dehumidifying function will not work. Press the FUNCTION selector so that the display indicates (DEHUMIDIFY). ˚ The FAN SPEED is set at LOW automatically. The FAN SPEED button does not work.
COOLING OPERATION Use the device for cooling when the outdoor temperature is –10~43°C. If in doors humidity is very high (80%), some dew may form on the air outlet grille of the indoor unit. Press the FUNCTION selector so that the display indicates (COOL).
FAN OPERATION You can use the device simply as an air circulator. Use this function to dry the interior of the indoor unit at the end of summer. Press the FUNCTION selector so that the display indicates (FAN). Press the (FAN SPEED) button.
HOW TO SET THE TIMER Time, Day, Month Set the current month and TIME, DAY, day with the TIMER control After you change the MONTH button. batteries; (current time, day, month) OFF TIMER RESET ON TIMER OFF-Timer Press the (OFF-TIMER) button.
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Set the current time with the Press the (TIME) button again. Press the TIMER control button. The time indication starts lighting (TIME) button. instead of flashing. The time indication will disappear automatically in 10 second. To check the current time setting, press the (TIME) button twice.
HOW TO SET THE SLEEP TIMER Set the current time at first if it is not set before (see the pages for setting the current time). Press the (SLEEP) button, and the display changes as shown below. Mode Indication 1 hour 2 hours 3 hours 7 hours...
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Explanation of the sleep timer The device will control the FAN SPEED and room temperature automatically so as to be quiet and good for people’s health. NOTE If date or current time is not set, sleep timer can not be set. If you set the sleep timer after the off-, on/off- or off/on-timer has been set, the sleep timer becomes effective instead of the off-, on/off- or off/ on-timer set earlier.
ADJUSTING THE AIR DEFLECTOR Adjustment of the conditioned air in the upward and downward directions. The horizontal air deflector is automatically set to the proper angle suitable for each operation. The deflector can be swung RESET up and down continuously and also set to the desired angle using the “...
HOW TO EXCHANGE THE BATTERIES IN THE REMOTE CONTROLLER Remove the cover as shown in the figure and take out the Push and pull to the old batteries. direction of arrow Install the new batteries. The direction of the batteries should match the marks in the case.
THE IDEAL WAYS OF OPERATION Suitable Room Temperature Install curtain or blinds Warning It is possible to Freezing temperature reduce heat is bad for health and a entering the waste of electric power. room through windows. Ventilation Effective Usage Of Timer At night, please use the “OFF or ON timer Caution operation mode”, together with your wake up...
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FOR USER’S INFORMATION The Air Conditioner And The Heat Source In The Room Caution If the amount of heat in the room is above the cooling capability of the air conditioner (for example: more people entering the room, using heating equipments and etc.), the preset room temperature cannot be achieved.
ATTACHING THE AIR CLEANSING FILTERS CAUTION Cleaning and maintenance must be carried out only by qualified service personal. Before cleaning, stop operation and switch off the power supply. Open the front panel. Pull up the front panel by holding it at both sides with both hands.
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MAINTENANCE CAUTION Cleaning and maintenance must be carried out only by qualified service personal. Before cleaning, stop operation and switch off the power supply. AIR FILTER Clean the air filter, as it removes dust inside the room. In case the air filter is full of dust, the air flow will decrease and the cooling capacity will be reduced.
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Washable Front Panel Remove the front panel and wash with clean water. Wash it with a soft sponge. After using neutral detergent, wash thoroughly with clean water. When front panel is not removed, wipe it with a soft dry cloth. Wipe the remote controller thoroughly with a soft dry cloth.
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CAUTION Cleaning and maintenance must be carried out only by qualified service personal. Before cleaning, stop operation and switch off the power supply. MAINTENANCE AT BEGINNING OF LONG OFF PERIOD Run the unit by setting the operation mode to (COOL), the temperature to 32°C and the fan speed to HI for about half a day on a fine day, and dry the whole of the unit.
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AFTER SALE SERVICE AND WARRANTY WHEN ASKING FOR SERVICE, CHECK THE FOLLOWING POINTS. CONDITION CHECK THE FOLLOWING POINTS Is the fuse all right? Is the voltage extremely high or low? When it does not operate Is the circuit breaker “ON”? Was the air filter cleaned? Does sunlight fall directly on the outdoor unit? Is the air flow of the outdoor unit obstructed?
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Please note: On switching on the equipment, particularly when the room light is dimmed, a slight brightness fluctuation may occur. This is of no consequence. The conditions of the local Power Supply Companies are to be observed. Note Avoid to use the room air conditioner for cooling operation when the outside temperature is below 21°C (70°F).
MAIN PARTS COMPONENT THERMOSTAT Thermostat Specifications MODEL RAK-50NH5 THERMOSTAT MODEL OPERATION MODE COOL HEAT 16.7 (62.1) 20.0 (68.0) INDICATION 16.0 (60.8) 20.7 (69.3) TEMPERATURE 24.7 (76.5) 28.0 (82.4) INDICATION °C (°F) 24.0 (75.2) 28.7 (83.7) 32.7 (90.9) 36.0 (96.8) INDICATION 32.0 (89.6)
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COMPRESSOR MOTOR Compressor Motor Specifications MODEL RAC-50NH5 COMPRESSOR MODEL JU1013D PHASE SINGLE RATED VOLTAGE AC 220 ~ 240 V RATED FREQUENCY 50 Hz POLE NUMBER WHITE CONNECTION YELLOW 20°C 2M = 1.05 (68°F) RESISTANCE VALUE 75°C 2M = 1.28 (167°F) WHITE YELLOW CAUTION...
WIRING DIAGRAM MODEL RAK-50NH5 / RAC-50NH5 OUTDOOR UNIT CN10 COMPRESSOR INDOOR UNIT OUTDOOR TEMPERATURE THERMISTOR WHT YEL RED DEFROST THERMISTOR WHT YEL U V W CN14 CN14 SYSTEM POWER MODULE 2 THERMISTOR REACTOR C503 C501 C502 CN13 CN13 CN15 JUMPER...
CIRCUIT DIAGRAM Remote Control Key matrix table Output Input Door open Start/Stop Operation selection Fan speed selection Automatic swing Door shut Start/Stop Automatic swing – – SEG20 SEG5 Door open On timer Hour up Hour down present time • SEG19 SEG0 SEG1 SEG18...
REFRIGERATING CYCLE DIAGRAM MODEL RA 50NH5 / RAC-50NH5 COOLING, DEHUMIDIFYING, DEFROSTING OUTDOOR UNIT SERVICE VALVE INDOOR UNIT (1/2) SINGLE-ENDED UNION (1/2) SUCTION TANK REVERSING VALVE ELECTRIC EXPANSION VALVE SERVICE VALVE (1/4) STRAINER SINGLE-ENDED UNION (1/4) STRAINER HEATING SERVICE VALVE OUTDOOR UNIT INDOOR UNIT (1/2) SINGLE-ENDED...
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2. Receiver Circuit R212 L201 Q141 R141 R211 R611 RECEIVER I/P Microcomputer Fig. 2-1 The light receiver unit receives the infrared signal from the wireless remote control. The receiver amplifies and shapes the signal and outputs it. 3. Buzzer Circuit R721 Microcomputer Buzzer output...
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4. Auto Sweep Motor Circuit Auto sweep motor for horizontal air defectors IC711 Rotor Microcomputer Fig.4-1 Fig. 4-1 shows the Auto sweep motor drive circuit; the signals shown in Fig.4-2 are output from pins – of microcomputer. Horizontal air Microcomputer pins Step width deflectors: 10ms.
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7. Initial Setting Circuit (IC401) When power is supplied, the microcomputer reads the data in IC401 or IC402 (E PROM) and sets the preheating activation value and the rating and maximum speed of the compressor, etc. to their initial values. Data of self-diagnosis mode is stored in IC401 or IC402;...
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(2) During ON The drain current at IC901 increases linearly. During this period, the gate voltage and current become constant because of the saturation characteristics of the transformer. (3) Shifting from ON to OFF This circuit applies a negative feedback signal from the 12V output. When the voltage across C919 reaches the specified value, REG2 turns on and current flows to PQ2 1-2.
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11. Outdoor DC Fan Motor control circuit. Ð Ð Ð – 93 –...
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< Reference > When operation stop with LD301 blinks 12 times, it may be caused by faulty DC fan motor. In this case, please check CN6 and CN12 connection first. It makes Fan Motor Lock also if those connectors are in misconnection. DC Fan Motor has broken when 2A Fuse was burned.
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12. Power Factor Control Circuit – 95 –...
TROUBLE SHOOTING Model RAK-50NH5 / RAC-50NH5 – 99 –...
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DISCHARGE PROCEDURE AND POWER SHUT OFF METHOD FOR POWER CIRCUIT Caution Voltage of about 300-330V is charged between both ends of smoothing capacitors During continuity check for each part of circuit in indoor unit electrical parts, disconnect red/gray WARNING lead wire connected from diode stack to system power module (SPM2) to prevent secondary trouble.
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CHECKING THE INDOOR/OUTDOOR UNIT ELECTRICAL PARTS AND REFRIGERATING CYCLE Model RAC-50NH5 Timer lamp See Troubleshooting when the timer lamp Does the timer lamp on the indoor unit blink? blinks . Remove the terminal cover and check the voltage between terminal (C) and terminal (D) Is approx.
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TROUBLESHOOTING WHEN TIMER LAMP BLINKS. Model RAK-50NH5 Perform troubleshooting according to the number of times the indoor timer lamp and outdoor LD301 blink. SELF-DIAGNOSIS LIGHTING MODE Model: RAK-50NH5 Blinking of Timer lamp Reason for indication Possible cause Reversing valve defective...
CHECKING INDOOR UNIT ELECTRICAL PARTS 1. Power does not come on (no operation) Is AC 220-240V AC being generated Is DC 35V being generated between Check AC outlet and breaker, and between terminals L and N on the terminals C and D on the terminal repair any defective part.
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2. Outdoor unit does not operate (but receives remote infrared signal) Check outdoor electrical parts, and repair any defective parts (around the outdoor interface transmitting circuit). Is the indoor transmitting signal Check the indoor interface being generated at Q801 s transmitting circuit.
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3. Only indoor fan does not operate (other is normal) Can the fan be stopped by The microcomputer fan PWM Replace the microcomputer. remote control? output (pin) is “Hi” Replace the indoor fan motor. Replace the microcomputer. Perform final operation check. 4.
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6. Check the main P.W.B (power circuit) Replace ICP2. Check if Is DC 35V being output Is ICP2 normal? shorting has occurred in fan between cathode and Normal if it is less than 1 motor circuit and 35V anode of D101? Blown (open) if it is 1 or more interface circuit.
CHECKING THE REMOTE CONTROLLER Is battery polarity correct? Install the battery in the correct polarity. Y es Y es Is the battery check sign Replace the battery. flashing? Turn on an AM radio, bring the remote control switch within 15 cm of the radio, and press the ON/OFF button.
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POWER CIRCUIT Phenomenon 1 <Rotation speed does not increase> Recheck cord, etc. of the Is the DC voltage at least 350V? system power module. If they are disconnected, connect them securely. Is the OVL lamp lit? If the lamp is lit, it does not If abnormality continues, indicate fault, but the unit replace the system...
(JUDGING BETWEEN GAS LEAKAGE AND CHECKING THE REFRIGERATING CYCLE COMPRESSOR DEFECTIVE) Troubleshooting procedure (No operation, No heating, No cooling) Lighting mode Blinks Blinks Blinks Blinks Blinks Blinks Connect U,V,W phase leads to the Self- 2 times 3 times 4 times 5 times 6 times 8times...
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HOW TO CHECK SYSTEM POWER MODULE Checking system power module using tester Set tester to resistance range (X 100) If indicator does not swing in the following conductivity check, the system power module is normal. (In case of digital tester, since built-in battery is set in reverse direction, + and – terminals are reversed.) CAUTION If inner circuit of system power module is disconnected (open), the indicator of tester will not swing and this may assumed as normal.
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HOW TO OPERATE USING THE SERVICE SWITCH THE OUTDOOR UNIT HOW TO OPERATE THE OUTDOOR UNIT INDEPENDENTLY – 117 –...
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SYSTEM POWER MODULE DIAGNOSIS Circuit diagram of Collector the device (excepting the reflux diode) BASE Emitter Circuit diagram of the module – Terminals symbol mark of the module See next page for measuring value using tester – L2 L1 – 118 –...
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Procedure for Disassem bly and Reassem bly INDOOR UNIT RAK-50NH5 1. Front Panel 3. Main P.W.B. and Reception/Indication (1)Pull up the washable panel by holding it at both P.W.B lower sides with both hands. (1)Remove each connector from the lead wire.
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4. Tangential air fl ow fan and fan motor (1)Remove two screws locking the drain pan. (2)Press to lower the hook at the center of the unit a little and pull the claw forward to remove the drain pan. Fig. 5 (3)Remove the screws from the upper and lower bearing covers.
PARTS LIST AND DIAGRAM INDOOR UNIT MODEL: RAK-50NH5 – 121 –...
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MODEL RAK-50NH5 PART N0. QTY / UNIT PARTS NAME RAK-50NH5 PMRAS-25YH 4 CABINET PMRAS-25YH 4 FAN MOTOR PMRAS-260GA TANGENTIAL AIR FLOW FAN PMRAS-25YH 4 FAN SUPPORT ASSEMBLY PMRAS-25YH 4 FAN COVER PMRAS-25YH 4 FAN MOTOR SUPPORT PMRAS-19SH4 CYCLE ASSY PMRAS-25YH 4...