Revision G: • MUZ-EF25/35/42VE - , MUZ-EF50VE - and MUZ-EF25/35VEH - have been added. Please void OBH590 REVISED EDITION-F. OUTDOOR UNIT No. OBH590 utilized REVISED EDITION-G SERVICE MANUAL R410A Models MUZ-EF25VE MUZ-EF25VEH MUZ-EF35VE MUZ-EF35VEH MUZ-EF42VE MUZ-EF50VE Indoor unit service manual MSZ-EF•VE Series (OBH589) CONTENTS MUZ-EF25VE MUZ-EF25VEH...
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Use the specifi ed 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.
SPECIFICATION 1 Measured under rated operating frequency. 2 MUZ-EF25/35/42VE- MUZ-EF25/35VEH- 3 MUZ-EF25/35/42VE- MUZ-EF25/35VEH- MUZ-EF25VE MUZ-EF35VE Outdoor model MUZ-EF42VE MUZ-EF50VE MUZ-EF25VEH MUZ-EF35VEH Power supply Single phase, 230 V, 50 Hz Cooling 2.5 (1.2 - 3.4) 3.5 (1.4 - 4.0) 4.2 (0.9 - 4.6) 5.0 (1.4 - 5.4) Capacity Rated frequency (Min.-Max.)
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Specifi cations and rated conditions of main electric parts Model MUZ-EF25VE MUZ-EF25VEH MUZ-EF35VE MUZ-EF35VEH MUZ-EF42VE MUZ-EF50VE Item 600 μF/620 μF 420 V (C61, C62) Smoothing 600 μF/620 μF 420 V capacitor (C63) — Diode module (DB61) 15 A 600 V 25 A 600 V (F61) T20AL250V...
OUTLINES AND DIMENSIONS MUZ-EF25VE MUZ-EF25VEH MUZ-EF35VE MUZ-EF35VEH MUZ-EF42VE Unit: mm REQUIRED SPACE *1 100 mm or more when front and sides of the unit are clear Drain hole ø42 (MUZ-EF25/35/42VE) Drain hole ø33 (MUZ-EF25/35VEH) Air in Air in *2 When any 2 sides of left, right 2 holes 10 X 21 and rear of the unit are clear Service panel...
PERFORMANCE CURVES MUZ-EF25VE MUZ-EF25VEH MUZ-EF35VE MUZ-EF35VEH MUZ-EF42VE MUZ-EF50VE The standard specifications apply only to the operation of the air conditioner under normal conditions. Since operating condi- tions vary according to the areas where these units are installed, the following information has been provided to clarify the operating characteristics of the air conditioner under the conditions indicated by the performance curve.
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Total input (Cooling : at Rated frequency 11.5 13.1 10.5 11.8 10.6 Indoor intake air Wet-bulb temperature( ) Outdoor intake air Dry-bulb temperature (°C) Heating capacity (at Rated frequency) 17.6 20.6 27.8 28.7 16.2 19.0 25.7 26.5 14.9 17.4 23.5 24.3 13.5 15.8...
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8-2. CAPACITY AND INPUT CORRECTION BY OPERATIONAL FREQUENCY OF COMPRESSOR MUZ-EF25VE MUZ-EF25VEH Correction of Cooling capacity Correction of Cooling input Correction of Heating capacity Correction of Heating input The operational frequency The operational frequency The operational frequency The operational frequency of compressor (Hz) of compressor (Hz) of compressor (Hz)
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8-3. HOW TO OPERATE FIXED-FREQUENCY OPERATION <Test run operation> 1. Press 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. Compressor operates at rated frequency in COOL mode or 58 Hz in HEAT mode. 4.
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Outdoor unit current MUZ-EF25VE MUZ-EF25VEH MUZ-EF35VE MUZ-EF35VEH MUZ-EF42VE Ambient temperature(°C) Ambient temperature (°C) Ambient temperature (°C) Ambient humidity(%) Ambient humidity(%) Ambient humidity(%) MUZ-EF50VE Ambient temperature (°C) Ambient humidity(%) 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 8-3.) Outdoor unit current...
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PERFORMANCE DATA COOL operation a t Rated frequency MUZ-EF25VE MUZ-EF25VEH CAPACITY: 2.5 kW SHF: 0.92 INPUT: 545 W OUTDOOR DB (°C) INDOOR INDOOR DB (°C) WB (°C) INPUT INPUT INPUT INPUT 2.94 2.17 0.74 2.81 2.08 0.74 2.70 2.00 0.74 2.60 1.92 0.74...
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PERFORMANCE DATA COOL operation a t Rated frequency MUZ-EF25VE MUZ-EF25VEH CAPACITY: 2.5 kW SHF: 0.92 INPUT: 545 W OUTDOOR DB (°C) INDOOR INDOOR DB (°C) WB (°C) INPUT INPUT INPUT 2.45 1.81 0.74 2.25 1.67 0.74 2.08 1.54 0.74 2.58 1.60 0.62 2.40...
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PERFORMANCE DATA COOL operation a t Rated frequency MUZ-EF35VE MUZ-EF35VEH CAPACITY: 3.5 kW SHF: 0.80 INPUT: 910 W OUTDOOR DB (°C) INDOOR INDOOR DB (°C) WB (°C) INPUT INPUT INPUT INPUT 4.11 2.55 0.62 3.94 2.44 0.62 3.78 2.34 0.62 3.64 2.26 0.62...
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PERFORMANCE DATA COOL operation a t Rated frequency MUZ-EF35VE MUZ-EF35VEH CAPACITY: 3.5 kW SHF: 0.80 INPUT: 910 W OUTDOOR DB (°C) INDOOR INDOOR DB (°C) WB (°C) INPUT INPUT INPUT 3.43 2.13 0.62 3.15 1.95 0.62 2.91 1.80 0.62 3.61 1.80 0.50 3.36...
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PERFORMANCE DATA COOL operation a t Rated frequency MUZ-EF42VE CAPACITY: 4.2 kW SHF: 0.72 INPUT: 1280 W OUTDOOR DB (°C) INDOOR INDOOR DB (°C) WB (°C) INPUT INPUT INPUT INPUT 4.94 2.66 0.54 1024 4.73 2.55 0.54 1075 4.54 2.45 0.54 1126 4.37...
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PERFORMANCE DATA COOL operation a t Rated frequency MUZ-EF42VE CAPACITY: 4.2 kW SHF: 0.72 INPUT: 1280 W OUTDOOR DB (°C) INDOOR INDOOR DB (°C) WB (°C) INPUT INPUT INPUT 4.12 2.22 0.54 1254 3.78 2.04 0.54 1331 3.49 1.88 0.54 1382 4.33 1.82...
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PERFORMANCE DATA COOL operation a t Rated frequency MUZ-EF50VE CAPACITY: 5.0 kW SHF: 0.71 INPUT: 1560 W OUTDOOR DB (°C) INDOOR INDOOR DB (°C) WB (°C) INPUT INPUT INPUT INPUT 5.88 3.11 0.53 1248 5.63 2.98 0.53 1310 5.40 2.86 0.53 1373 5.20...
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PERFORMANCE DATA COOL operation a t Rated frequency MUZ-EF50VE CAPACITY: 5.0 kW SHF: 0.71 INPUT: 1560 W OUTDOOR DB (°C) INDOOR INDOOR DB (°C) WB (°C) INPUT INPUT INPUT 4.90 2.60 0.53 1529 4.50 2.39 0.53 1622 4.15 2.20 0.53 1685 5.15 2.11...
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PERFORMANCE DATA HEAT operation at Rated frequency MUZ-EF25VE MUZ-EF25VEH CAPACITY: 3.2 kW INPUT: 700 W OUTDOOR WB (°C) INDOOR DB (°C) INPUT INPUT INPUT INPUT INPUT INPUT INPUT 2.02 2.43 2.85 3.26 3.68 4.06 4.48 1.92 2.30 2.72 3.10 3.52 3.90 4.30 1.73...
ACTUATOR CONTROL MUZ-EF25VE MUZ-EF25VEH MUZ-EF35VE MUZ-EF35VEH MUZ-EF42VE MUZ-EF50VE 9-1. OUTDOOR FAN MOTOR CONTROL The fan motor turns ON/OFF, interlocking with the compressor. [ON] The fan motor turns ON 5 seconds before the compressor starts up. [OFF] The fan motor turns OFF 15 seconds after the compressor has stopped running. 5 seconds 15 seconds Compressor...
SERVICE FUNCTIONS MUZ-EF25VE MUZ-EF25VEH MUZ-EF35VE MUZ-EF35VEH MUZ-EF42VE MUZ-EF50VE 10-1. CHANGE IN DEFROST SETTING Changing defrost finish temperature <JS> To change the defrost finish temperature, cut/solder the JS wire of the outdoor inverter P.C. board. (Refer to 11-6-1.) Defrost fi nish temperature (°C) MUZ-EF25VE - Jumper wire MUZ-EF25VE -...
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11-2. FAILURE MODE RECALL FUNCTION Outline of the function This air conditioner can memorize the abnormal condition which has occurred once. Even though LED indication listed on the troubleshooting check table (11-3.) disappears, the memorized failure details can be recalled. 1.
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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. 1.
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3. Outdoor unit failure mode table The left lamp of Indoor/outdoor Outdoor unit OPERATION Abnormal point LED indication unit failure Condition Remedy failure mode INDICATOR (Failure mode/protection) (Outdoor P.C. board) mode recall recall function lamp function (Indoor unit) None (Normal) —...
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The left lamp of Indoor/outdoor Outdoor unit OPERATION Abnormal point LED indication unit failure Condition Remedy failure mode INDICATOR (Failure mode/protection) (Outdoor P.C. board) mode recall recall function lamp function (Indoor unit) 10-time fl ash Discharge temperature Temperature of discharge temperature •...
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11-3. TROUBLESHOOTING CHECK TABLE Abnormal point/ Symptom LED indication Condition Remedy Condition Outdoor unit 1-time fl ash every Outdoor power sys- Overcurrent protection cut-out operates 3 consecutive times • Reconnect connector of compres- does not op- 2.5 seconds within 1 minute after the compressor gets started. sor.
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11-3. TROUBLESHOOTING CHECK TABLE Abnormal point/ Symptom LED indication Condition Remedy Condition Outdoor unit 7-time fl ash Low discharge tem- Temperature of discharge temperature thermistor has been • Refer to 11-5. "Check of LEV". operates. 2.5 seconds OFF perature protection 50°C or less for 20 minutes.
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11-4. TROUBLE CRITERION OF MAIN PARTS MUZ-EF25VE MUZ-EF25VEH MUZ-EF35VE MUZ-EF35VEH MUZ-EF42VE MUZ-EF50VE Part name Check method and criterion Figure Defrost thermistor (RT61) Fin temperature thermistor (RT64) Measure the resistance with a tester. Ambient temperature Refer to 11-6. “Test point diagram and voltage”, 1. “Inverter P.C. thermistor (RT65) board”, for the chart of thermistor.
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11-5. TROUBLESHOOTING FLOW A How to check inverter/compressor Disconnect the connector between compressor and the intelligent power module (IC700). Check the voltage between terminals. See 11-5. “Check of open phase”. Replace the inverter P.C. board. Are the voltages balanced? Check the compressor. See 11-5.
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D Check of compressor winding ●Disconnect the connector between the compressor and intelligent power module, and measure the resistance between the compressor terminals. <<Measurement point>> At 3 points BLK-WHT BLK-RED Measure the resistance between the lead wires at 3 points. WHT-RED <<Judgement>>...
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G Check of outdoor thermistors Disconnect the connector of thermistor in the inverter P.C. board (see below table), and measure the resistance of thermistor. Replace the thermistor except RT64. Is the resistance of thermistor normal? When RT64 is abnormal, replace the inverter P.C. (Refer to 11-6.1.) board.
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I Check of outdoor fan motor Disconnect the connectors CN931 and CN932 from the inverter P.C. board. Check the connection between the connector CN931 and CN932. Is the resistance between each ter- minal of outdoor fan motor normal? (Refer to 11-4.) Disconnect CN932 from the inverter P.C.
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J Check of power supply Disconnect the connector between compressor and inverter module. Rectify indoor/outdoor Turn ON power supply and press connecting wire. EMERGENCY OPERATION switch. Does the left lamp of OPERATION Is there voltage 230 VAC Replace the indoor INDICATOR lamp on the indoor unit between the indoor terminal electronic control P.C.
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K Check of LEV (Expansion valve) MSZ-EF•VEW/B/S MSZ-EF•VE2W/B/S MSZ-EF•VE3W/B/S Turn ON the power supply. <Preparation of the remote controller> While pressing both OPERATION SELECT button and TEMP button on the remote controller at the same time, press RESET button. First, release RESET button. Hold down the other 2 buttons for another 3 seconds.
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L Check of inverter P.C. board Check the outdoor fan motor. (Refer to 11-5. .) Is the fuse (F901) blown on the in- verter P.C. board? Check the connection of the connectors (CN931, CN932) of the outdoor fan motor. If the connection is poor, make it correct. Operate the outdoor unit by starting EMERGENCY OPERATION.
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M How to check miswiring and serial signal error Turn the main power supply OFF. Is there rated voltage in the power supply? Check the power supply. Check for incorrect indoor-outdoor connecting wiring. Was the indoor unit ever connected to the Multi (MXZ) series and operated (turned on)? The connection information to the Multi series is stored...
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N Check of defrost heater MUZ-EF•VEH Check the following points before checking electric continuity. 1. Does the resistance of ambient temperature thermistor have the characteristics? Refer to 11-6.1. 2. Is the resistance of defrost heater normal? Refer to 11-4. 3. Does the heater protector remain conducted (not open)? 4.
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P Electromagnetic noise enters into TV sets or radios Is the unit earthed? Earth the unit. Is the distance between the antennas Extend the distance between the antennas and and the indoor unit within 3 m, or is the the indoor unit, and/or the antennas and the distance between the antennas and the outdoor unit.
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11-6. TEST POINT DIAGRAM AND VOLTAGE 1. Inverter P.C. board MUZ-EF25VE MUZ-EF25VEH MUZ-EF35VE MUZ-EF35VEH MUZ-EF42VE MUZ-EF50VE Heater connector (CN722) Smoothing Smoothing Smoothing R.V.coil MUZ-EF25/35VEH capacitor (C63) capacitor capacitor (CN721) DB61 MUZ-EF42/50VE Back side of unit MUZ-EF42/50VE (C62) (C61) 230 VAC 260 - 370 VDC Fuse (F701) T3.15AL250V...
DISASSEMBLY INSTRUCTIONS <"Terminal with locking mechanism" Detaching points> The terminal which has the locking mechanism can be detached as shown below. There are 2 types (refer to (1) and (2)) 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, inverter P.C. board Photo 3 (1) Remove the cabinet and panels. (Refer to 1.) Screws of the heat sink Screws of the terminal block (2) Disconnect the lead wire to the reactor and the following con- support and the separator support and the back panel nectors:...
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OPERATING PROCEDURE PHOTOS 5. Removing outdoor fan motor Photo 6 Ambient temperature (1) Remove the cabinet and panels. (Refer to 1.) thermistor (2) Disconnect the following connectors: <Inverter P.C. board> CN931, CN932 (Fan motor) (3) Remove the propeller fan nut. Outdoor heat (4) Remove the propeller fan.
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12-2. MUZ-EF50VE NOTE: Turn OFF the power supply before disassembly. OPERATING PROCEDURE PHOTOS 1. Removing the cabinet Photo 1 (1) Remove the screws of the service panel. Screws of the top panel (2) Remove the screws of the top panel. (3) Remove the screw of the valve cover.
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OPERATING PROCEDURE PHOTOS 2. Removing the inverter assembly, inverter P.C. board Photo 3 Screws of the terminal (1) Remove the cabinet and panels. (Refer to 1.) Screw of the heat sink block support and the (2) Disconnect the lead wire to the reactor and the following con- support and the separator back panel nectors:...
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OPERATING PROCEDURE PHOTOS 4. Removing the discharge temperature thermistor, Photo 6 defrost thermistor, outdoor heat exchanger tempera- Outdoor heat Ambient tem- perature exchanger tempera- ture thermistor and ambient temperature thermistor ture thermistor thermistor (1) Remove the cabinet and panels. (Refer to 1.) (2) Disconnect the lead wire to the reactor and the following connectors: <Inverter P.C.