Revision B: • MXZ-2HA40/50VF- MXZ-3HA50VF- have been added. OBH828 REVISED EDITION-A is void. OUTDOOR UNIT No. OBH828 utilized REVISED EDITION-B SERVICE MANUAL Models MXZ-2HA40VF MXZ-2HA50VF MXZ-3HA50VF Indoor unit service manual MSZ-HR•VF Series (OBH822) CONTENTS 1. TECHNICAL CHANGES ······························3 2. SAFETY PRECAUTION ·······························3 3.
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Use the specified refrigerant only Never use any refrigerant other than that specified. Doing so may cause a burst, an explosion, or fire when the unit is being used, serviced, or disposed of. Correct refrigerant is specified in the manuals and on the spec labels provided with our products. We will not be held responsible for mechanical failure, system malfunction, unit breakdown or accidents caused by failure to follow the instructions.
TECHNICAL CHANGES MXZ-2HA40VF - MXZ-2HA50VF - MXZ-3HA50VF - 1. New model MXZ-2HA40VF - MXZ-2HA40VF - MXZ-2HA50VF - MXZ-2HA50VF - MXZ-3HA50VF - MXZ-3HA50VF - 1. Model name has been changed. MXZ-2HA40VF - MXZ-2HA50VF - MXZ-3HA50VF - 1. New model SAFETY PRECAUTION MEANINGS OF SYMBOLS DISPLAYED ON THE UNIT This mark is for R32 refrigerant only.
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Use the following tools specifically designed for Make sure that the inside and outside of refrige- use with R32 refrigerant. rant piping is clean and it has no contaminants such as sulfur, oxides, dirt, shaving particles, etc, The following tools are necessary to use R32 refrigerant. which are hazard to refrigerant cycle.
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[1] Warning for service (1) Do not alter the unit. (2) For installation and relocation work, follow the instructions in the Installation Manual and use tools and pipe components specifically made for use with refrigerant specified in the outdoor unit installation manual. (3) Ask a dealer or an authorized technician to install, relocate and repair the unit.
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[4] Cautions for unit using R32 refrigerant Basic work procedures are the same as those for conventional units using refrigerant R410A. However, pay careful attention to the following points. (1) Information on servicing (1-1) Checks on the Area Prior to beginning work on systems containing flammable refrigerants, safety checks are necessary to ensure that the risk of ignition is minimized.
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(3) Repair to intrinsically Safe Components Do not apply any permanent inductive or capacitance loads to the circuit without ensuring that this will not exceed the permissible voltage and current permitted for the equipment in use. Intrinsically safe components are the only types that can be worked on while live in the presence of a flammable atmos- phere.
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b) Isolate system electrically. c) Before attempting the procedure, ensure that: • mechanical handling equipment is available, if required, for handling refrigerant cylinders; • all personal protective equipment is available and being used correctly; • the recovery process is supervised at all times by a competent person; •...
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[5] Service tools Use the below service tools as exclusive tools for R32 refrigerant. Tool name Specifications Gauge manifold · Only for R32 · Use the existing fitting specifications . (UNF1/2) · Use high-tension side pressure of 5.3MPa·G or over. Charge hose ·...
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(2) Cautions for refrigerant piping work New refrigerant R32 is adopted for replacement inverter series. Although the refrigerant piping work for R32 is same as for R22, exclusive tools are necessary so as not to mix with different kind of refrigerant. Furthermore as the working pressure of R32 is 1.6 times higher than that of R22, their sizes of flared sections and flare nuts are different.
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2-4. CHOOSING THE OUTDOOR UNIT INSTALLATION LOCATION R32 is heavier than air—as well as other refrigerants— so tends to accumulate at the base (in the vicinity of the floor). If R32 accumulates around base, it may reach a flammable concentration in case room is small. To avoid ignition, maintaining a safe work environment is required by ensuring appropriate ventilation.
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C) Create an appropriate ventilation open area. Make sure that the width of the open area is 0.9 [m] or more and the height of the open area is 0.15 [m] or more. However, the height from the bottom of the installation space to the bottom edge of the open area should be 0.125 [m] or less.
PART NAMES AND FUNCTIONS MXZ-2HA40VF MXZ-2HA50VF Air inlet (Back and side) Piping Drain hose Air outlet Drain outlet MXZ-3HA50VF Air inlet (Back and side) Air outlet Drain outlet ACCESSORIES MXZ-2HA40VF Model MXZ-3HA50VF MXZ-2HA50VF Drain socket Drain cap OBH828B...
SPECIFICATION Outdoor model MXZ-2HA40VF Single phase Outdoor unit power supply 220 - 230 - 240 V, 50 Hz Indoor units number Piping total length Max. 30 Connecting pipe length Max. 20 Height difference (Indoor ~ Outdoor) Refer to 8 REFRIGERANT SYSTEM DIAGRAM. Height difference (Indoor ~ Indoor) Refer to 8 REFRIGERANT SYSTEM DIAGRAM.
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Outdoor model MXZ-2HA50VF Single phase Outdoor unit power supply 220 - 230 - 240 V, 50 Hz Indoor units number Piping total length Max. 30 Connecting pipe length Max. 20 Height difference (Indoor ~ Outdoor) Refer to 8 REFRIGERANT SYSTEM DIAGRAM. Height difference (Indoor ~ Indoor) Refer to 8 REFRIGERANT SYSTEM DIAGRAM.
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Outdoor model MXZ-3HA50VF Single phase Outdoor unit power supply 220 - 230 - 240 V, 50 Hz Indoor units number 2 to 3 Piping total length Max. 50 Connecting pipe length Max. 25 Height difference (Indoor ~ Outdoor) Refer to 8 REFRIGERANT SYSTEM DIAGRAM. Height difference (Indoor ~ Indoor) Refer to 8 REFRIGERANT SYSTEM DIAGRAM.
NOISE CRITERIA CURVES MXZ-2HA40VF MXZ-2HA50VF FAN SPEED FUNCTION SPL(dB LINE FAN SPEED FUNCTION SPL(dB LINE High Cooling High Cooling High Heating High Heating NC-70 NC-70 NC-60 NC-60 NC-50 NC-50 NC-40 NC-40 NC-30 NC-30 APPROXIMATE APPROXIMATE THRESHOLD OF THRESHOLD OF NC-20 HEARING FOR NC-20 HEARING FOR...
OUTLINES AND DIMENSIONS MXZ-2HA40VF MXZ-2HA50VF Unit: mm (inch) OBH828B...
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MXZ-3HA50VF Unit: mm (inch) 1.Installation space 2.Service space Note : Leave front and both sides 100 or more free of obstruction. 100 or more Service space 350 or more 350 or more Note : Leave front and overhead free of obstruction. 350 or more 100 or more Note : Leave rear, overhead and...
REFRIGERANT SYSTEM DIAGRAM MXZ-2HA40VF MXZ-2HA50VF UNIT: mm Compressor Discharge R.V. coil temperature Refrigerant flow in cooling thermistor RT62 Refrigerant flow in heating Muffler Indoor unit 4-way valve Stop valve Sub muffler (with service port) Indoor unit Outdoor heat Stop valve exchanger (with service port) temperature...
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MXZ-3HA50VF UNIT: mm Compressor High-pressure switch Discharge R.V. coil temperature Charge pipe Refrigerant flow in cooling thermistor RT62 Oil separator Refrigerant flow in heating 4-way Capillary tube valve Indoor unit Stop valve with service port Indoor unit Outdoor heat Muffler exchanger Indoor unit temperature...
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PUMPING DOWN When relocating or disposing of the air conditioner, pump down the system following the procedure below so that no refrigerant is released into the atmosphere. 1) Turn off the breaker. 2) Connect the gauge manifold valve to the service port of the stop valve on the gas pipe side of the outdoor unit. 3) Fully close the stop valve on the liquid pipe side of the outdoor unit.
PERFORMANCE CURVES MXZ-2HA40VF MXZ-2HA50VF MXZ-3HA50VF The standard specifications apply only to the operation of the air conditioner under normal conditions. Since operating conditions vary according to the areas where these units are installed, the following information has been pro- vided to clarify the operating characteristics of the air conditioner under the conditions indicated by the performance curve. (1) GUARANTEED VOLTAGE 198 - 264 V 50 Hz (2) AIR FLOW...
9-1. CAPACITY AND THE INPUT CURVES MXZ-2HA40VF MXZ-2HA50VF Cooling capacity 11.1 10.2 20 25 35 40 Outdoor intake air Dry - bulb temperature (ºC) Total input (Cooling) 26 24 20 25 35 40 Outdoor intake air Dry - bulb temperature (ºC) Heating capacity 21.3 22.2...
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MXZ-3HA50VF Cooling capacity 11.1 12.8 10.2 11.6 10.5 45 46 Outdoor intake air Dry - bulb temperature ( ºC Total input (Cooling) 45 46 Outdoor intake air Dry - bulb temperature ( ºC Heating capacity 21.3 22.2 29.9 38.4 19.8 20.6 27.8 35.7...
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9-2. CAPACITY AND INPUT CORRECTION BY INVERTER OUTPUT FREQUENCY (single operation) MXZ-2HA40VF 25-class unit <COOL>Total input <HEAT>Total input <COOL>Capacity <HEAT>Capacity Frequency Frequency Frequency Frequency 35-class unit <COOL>Total input <HEAT>Total input <COOL>Capacity <HEAT>Capacity Frequency Frequency Frequency Frequency OBH828B...
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MXZ-2HA50VF 25-class unit <COOL>Total input <HEAT>Total input <COOL>Capacity <HEAT>Capacity Frequency Frequency Frequency Frequency 35-class unit <COOL>Total input <HEAT>Total input <COOL>Capacity <HEAT>Capacity Frequency Frequency Frequency Frequency 42-class unit <COOL>Total input <HEAT>Total input <COOL>Capacity <HEAT>Capacity Frequency Frequency Frequency Frequency OBH828B...
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MXZ-3HA50VF 25-class unit <COOL>Total input <HEAT>Total input <COOL>Capacity <HEAT>Capacity Frequency Frequency Frequency Frequency 35-class unit <COOL>Total input <HEAT>Total input <COOL>Capacity <HEAT>Capacity Frequency Frequency Frequency Frequency 42-class unit <COOL>Total input <HEAT>Total input <COOL>Capacity <HEAT>Capacity Frequency Frequency Frequency Frequency 50-class unit <COOL>Total input <HEAT>Total input <COOL>Capacity <HEAT>Capacity...
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9-3. HOW TO OPERATE FIXED-FREQUENCY OPERATION <Test run operation> 1. Press the emergency operation switch to start COOL or HEAT mode (COOL : Press once, HEAT : Press twice). 2. Test run operation starts and continues to operate for 30 minutes. 3.
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MXZ-3HA50VF 25-class unit 35-class unit (MPa[Gauge]) (MPa[Gauge]) 40Hz 40Hz 40Hz 40Hz (°C) (°C) (°C) (°C) Ambient temperature ( ) Ambient temperature ( ) Ambient temperature ( ) Ambient temperature ( ) Ambient humidity (%) Ambient humidity (%) Ambient humidity (%) Ambient humidity (%) 42-class unit 50-class unit...
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(2) HEAT operation Condition : Indoor Outdoor Dry bulb temperature (°C) 20.0 20.0 Wet bulb temperature (°C) 14.5 14.5 Operation : TEST RUN OPERATION (Refer to 9-3.) MXZ-2HA40VF 25-class unit 35-class unit 34Hz 34Hz Ambient temperature ( ) Ambient temperature ( ) MXZ-2HA50VF 25-class unit 35-class unit...
ACTUATOR CONTROL MXZ-2HA40VF MXZ-2HA50VF Relation between main sensor and actuator Actuator Sensor Purpose Outdoor Compressor R.V. coil fan motor Discharge temperature thermistor Protection Cooling: Coil frost prevention Indoor coil temperature thermistor Heating: High pressure protection Defrost thermistor Heating: Defrosting Fin temperature thermistor Protection Control/Protection Ambient temperature thermistor...
SERVICE FUNCTIONS MXZ-2HA40VF MXZ-2HA50VF MXZ-3HA50VF 11-1. THE POSITION OF SWITCH <MXZ-2HA40VF/2HA50VF> 1 2 3 4 5 6 Outdoor display P.C. board <MXZ-3HA50VF> SW871 CN750 1 2 3 4 5 6 CN751 1 2 3 4 5 6 Outdoor control P.C. board 11-2.
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11-3. LOWERING THE OPERATING NOISE OF THE OUTDOOR UNIT With this function, the operating noise of the outdoor unit can be lowered by reducing the operation load, for example, during nighttime in COOL mode. However, note that the cooling and heating capacity may lower if this function is activated. Changing the setting is required to activate this function.
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11-4. AUTOMATIC LINE CORRECTING <MXZ-2HA40VF/2HA50VF> This outdoor unit has an automatic line correcting function which automatically detects and corrects improper wiring or piping. <MXZ-2HA40VF/2HA50VF> Improper wiring or piping can be automatically detected when one indoor unit is operated in COOL mode for 30 minutes. When improper wiring or piping is detected, wiring lines are corrected (A to B/ B to A) with the software.
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<MXZ-3HA50VF> Outdoor unit has an auto line correcting function which automatically detects and corrects improper wiring or piping. Improper wiring or piping can be automatically detected by pressing the piping/wiring correction switch (SW871). When improper wiring or piping is detected, wiring lines are corrected. This will be completed in about 10 to 15 minutes.
TROUBLESHOOTING MXZ-2HA40VF MXZ-2HA50VF MXZ-3HA50VF 12-1. CAUTIONS ON TROUBLESHOOTING 1. Before troubleshooting, check the following: 1) Check the power supply voltage. 2) Check the indoor/outdoor connecting wire for miswiring. 2. Take care of the following during servicing 1) Before servicing the air conditioner, be sure to turn OFF the unit first with the remote controller, and after confirming the horizontal vane is closed, turn OFF the breaker and/or disconnect the power plug.
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2. Flow chart of the detailed outdoor unit failure mode recall function Operational procedure The outdoor unit might be abnormal. Check if outdoor unit is abnormal according to the following procedures. Make sure that the remote controller is set to the failure mode recall function. With the remote controller headed towards the indoor unit, press the Temperature buttons to adjust the set temperature to 25°C.
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NOTE: Blinking patterns of this mode differ from the ones of 3. Table of outdoor unit failure mode recall function Troubleshooting check table (12-4). MXZ-2HA Upper or LED indication Indoor/ left lamp of (Outdoor P.C. board) outdoor OPERATION Abnormal point unit failure LED 1 LED 2...
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NOTE: Blinking patterns of this mode differ from the ones of Troubleshooting check table (12-4.). MXZ-3HA LED indication The left lamp of Indoor/ (Outdoor P.C. OPERATION IN- Abnormal point outdoor unit Condition Remedy board) DICATOR lamp (Failure mode/protection) failure mode (Indoor unit) recall function LED1...
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12-3. INSTRUCTION OF TROUBLESHOOTING • Check the indoor unit referring to the indoor unit service manual, and confirm that there is any problem in the indoor unit. Then, check the outdoor unit with referring to this page. Operation start Check the outdoor unit LED indicator.
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12-4. TROUBLESHOOTING CHECK TABLE MXZ-2HA Symptom Indication Abnormal point / Condition Condition Remedy LED1(Red) LED2(Yellow) Outdoor unit • Refer to 12-6. "Check of LEV". The indoor unit detects an abnormality in the LEV and drain pump. Once LEV and drain pump does not •...
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Indication No. Symptom Abnormal point / Condition Condition Remedy LED1(Red) LED2(Yellow) Outdoor unit This symptom does not mean any abnormality of the operates. product, but check the following points. Cooling high pressure 5 times The outdoor heat exchanger temperature exceeds 58°C during operation. •...
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MXZ-3HA Indication Abnormal point / Con- Symptom Condition Remedy dition LED1(Red) LED2(Yellow) Outdoor The indoor unit detects an abnormality in the LEV • Refer to 12-6. "Check of LEV". Once LEV and drain pump unit does and drain pump. • Check the drain pump of the indoor unit. not operate.
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Indication Abnormal point / Con- Symptom Condition Remedy dition LED1(Red) LED2(Yellow) 22 'Outdoor unit A failure occurs 3 consecutive times within 30 13 times Not lit Outdoor fan motor • Refer to 12-6. "Check of outdoor fan motor". stops and seconds after the fan gets started.
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12-5. TROUBLE CRITERION OF MAIN PARTS MXZ-2HA40VF MXZ-2HA50VF MXZ-3HA50VF Part name Check method and criterion Defrost thermistor (RT61) Measure the resistance with a tester. Fin temperature thermistor (RT64) Ambient temperature thermistor (RT65) Refer to 12-7. "TEST POINT DIAGRAM AND VOLTAGE" 1. "Inverter P.C. board", 2. Outdoor heat exchanger "Outdoor control P.C.
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12-6. TROUBLESHOOTING FLOW Outdoor unit does not operate. Check of power supply MXZ-2HA40VF/2HA50VF Check the main power supply circuit for proper connections. Turn ON the power supply. Is there voltage of 220 - 230 - 240 V AC Check the power supply and correct them. in the power supply terminal block? Is there voltage of 220 - 230 - 240 V AC Replace the inverter P.C.
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• When the indoor unit does not operate, it cannot be operated either with the remote controller or with the emergen- cy operation switch. • When the outdoor unit does not operate, the OPERATION INDICATOR lamp on the indoor unit blinks ON and OFF every 0.5-second.
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MXZ-3HA50VF Turn OFF the power supply. LED indication for communication status Communication status is indicated Is there rated voltage in by the LED. Check the power the power supply? supply. Unit status Blinking: normal communication Lit: abnormal communication or not connected Turn ON the power supply.
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The cooling operation or heating operation does not operate. Check of R.V. coil Connector MXZ-2HA MXZ-2HA40VF/2HA50VF CN721 Inverter P.C. board • The heating operation does not operate. 1. Disconnect the lead wire leading to the compressor. 2. 3 minutes after turning ON the power supply, start EMERGENCY OPERATION in HEAT mode.
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MXZ-3HA50VF Connector MXZ-3HA CNAC Outdoor control • When cooling operation does not work. CN712 P.C. board 1. Disconnect the lead wire leading to the compressor. Outdoor power CNAC2 2. 3 minutes after turning ON the power supply, start EMERGENCY P.C. board OPERATION in COOL mode.
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• When cooling, heat exchanger of non-operating indoor unit frosts. • When heating, non-operating indoor unit gets warm. Check of LEV Connector MXZ-2HA MXZ-3HA CN724 Inverter P.C. board CN725 CN791 CN792 Outdoor control CN793 P.C. board Turn ON the power supply to the outdoor unit after checking LEV ―...
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• When heating, room does not get warm. • When cooling, room does not get cool. How to check inverter/compressor Disconnect the terminal of the compressor or the connector (CNMC) between the compressor and the outdoor power P.C. board. 3 minutes after the power supply is turned ON, start EMERGENCY OPERATION.
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• When thermistor is abnormal. Check of outdoor thermistors Disconnect the connector in the following table and Replace the thermistor except RT64. measure the resistance of the thermistor to check If RT64 is abnormal, replace the outdoor power whether the thermistor is normal or not. (Refer to 12-7.) Abnormal P.C.
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• Fan motor does not operate or stops operating shortly after starting the operation. Check of outdoor fan motor MXZ-2HA40VF/2HA50VF Connector MXZ-2HA CN931 Inverter P.C. board Disconnect CN932 and measure the CN932 resistance of the outdoor fan motor. Is the resistance of outdoor fan motor normal? (Refer to 12-5.) Turn ON the breaker.
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MXZ-3HA50VF MXZ-3HA Connector Disconnect CNF1 and measure the resistance of the outdoor fan motor. Outdoor control CNF1 P.C. board Is the resistance of outdoor fan motor Measuring points Resistance Replace the outdoor fan motor. normal? (Refer to right table.) pin1 - pin4 pin5 - pin4 60 kΩ...
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• When the operation frequency does not go up from the lowest frequency. Connector MXZ-3HA Check of HPS Outdoor control CN63H P.C. board MXZ-3HA50VF 1. Disconnect the connector CN63H in the outdoor control P.C. board. 2. Check the resistance of HPS after 1 minute has passed since the outdoor unit power supply was turned OFF. Replace HPS.
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Check of outdoor refrigerant circuit MXZ-2HA40VF/2HA50VF The operation has stopped to prevent the diesel explosion caused by air trapped in the refrigerant circuit. Close the stop Has the operation stopped during pump down? valve, and disconnect the power plug or turn the breaker OFF. CAUTION: Do not start the operation again to prevent hazards.
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12-7. TEST POINT DIAGRAM AND VOLTAGE 1. Inverter P.C. board MXZ-2HA40VF MXZ-2HA50VF Back side of unit R.V. coil (CN721) Heater (CN722) 220-230-240 V AC 280 - 370 V DC FUSE (F901) Smoothing capacitor FUSE (F801) (LD66A, LD70) (DB61(+), (-)) T3.15AL250V (C61, C62, C63) T3.15AL250V FUSE (F701)
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2. Outdoor control P.C. board Defrost thermistor (RT61) Ambient temperature thermistor (RT65) MXZ-3HA50VF Outdoor heat exchanger temperature thermistor (RT68) Serial signal 12 ~ 24 V 220 - 230 - 240 V AC Room B CN741 Room A Room C Input Signal translation (To Communication adaptor board)
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3. Outdoor power P.C. board MXZ-3HA50VF CN151 Signal transmission (To Outdoor control P.C. board) 15 V 5 V DC pulse wave 15 V Output to drive compressor CN171 Fin temperature thermistor CN152 (RT64) Signal Transmission (From Outdoor Control P.C. board) 5 V DC pulse wave Connect to earth CNAC2...
DISASSEMBLY INSTRUCTIONS <Detaching method of the terminal with locking mechanism> The terminal which has the locking mechanism can be detached as shown below. There are following 2 types of the terminal with locking mechanism. The terminal without locking mechanism can be detached by pulling it out. Check the shape of the terminal before detaching.
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OPERATING PROCEDURE PHOTOS 2. Removing the inverter assembly and the inverter Photo 4 P.C. board Screws of the heat sink (1) Remove the service panel, the top panel and the cabinet Inverter support and the separator (Refer to 1). assembly (2) Disconnect the power supply and indoor/outdoor connect- ing wire and remove the back panel (Refer to section 1).
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OPERATING PROCEDURE PHOTOS 5. Removing the outdoor fan motor Photo 7 (1) Remove the service panel, the top panel and the cabinet Outdoor heat (Refer to section 1). exchanger (2) Disconnect the power supply and indoor/outdoor connect- temperature ing wire. thermistor (RT68) (3) Disconnect the connectors for outdoor fan motor.
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13-2. MXZ-3HA50VF NOTE: Turn OFF the power supply before disassembly. OPERATING PROCEDURE PHOTOS 1. Removing the cabinet and the panels Photo 1 (1) Remove the screws of the service panel, and remove the service panel. Screws of the (2) Disconnect the power supply and indoor/outdoor connect- top panel ing wire.
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OPERATING PROCEDURE PHOTOS Photo 4 2. Removing the outdoor control P.C. board, the out- door power P.C. board and the reactor Electrical (1) Remove the service panel (Photo 1). Catch of the electrical box assembly box assembly (2) Disconnect the power supply and indoor/outdoor con- necting wire.
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OPERATING PROCEDURE PHOTOS . Removing the fan motor Photo 8 Screws of the outdoor fan motor (1) Remove the service panel (Photo 1). (2) Disconnect the power supply and indoor/outdoor connect- ing wire. (3) Remove the top panel, the cabinet, and the back panel (Photo 1, 2, 3).