OUTDOOR UNIT No. OBH625 SERVICE MANUAL REVISED EDITION-G utilized R410A Models MUZ-FH25VEHZ MUZ-FH35VEHZ MUZ-FH50VEHZ Indoor unit service manual MSZ-FH•VE Series (OBH623) CONTENTS 1. TECHNICAL CHANGES ······························3 2. PART NAMES AND FUNCTIONS ··················4 3. SPECIFICATION ········································5 4. NOISE CRITERIA CURVES ··························8 5.
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, MUZ-FH25VEHZ- and MUZ-FH50VEHZ- have been added. Revision C: • MUZ-FH25VEHZ- and MUZ-FH25VEHZ- have been added. Revision D: • MUZ-FH25VEHZ- , MUZ-FH35VEHZ- and MUZ-FH50VEHZ- have been added. Revision E: • MUZ-FH25VEHZ- , MUZ-FH35VEHZ- and MUZ-FH50VEHZ- have been added. Revision F: •...
PART NAMES AND FUNCTIONS MUZ-FH25VEHZ MUZ-FH35VEHZ Air inlet (back and side) Piping Drain hose Air outlet Drain outlet MUZ-FH50VEHZ - Air inlet (back and side) Piping Drain hose Air outlet Drain outlet MUZ-FH50VEHZ - Air inlet (back and side) Piping...
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MUZ-FH50VEHZ Outdoor model Power supply Single phase, 230 V, 50 Hz Cooling 5.0 (1.9 - 6.0) Capacity Rated (Min. - Max.) Heating 6.0 (1.7 - 8.7) Breaker Capacity Cooling 1,380 Power input *1 (Set) Heating 1,480 Cooling Running current *1 (Set) Heating Cooling Power factor *1 (Set)
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Specifications and rated conditions of main electric parts Model MUZ-FH25VEHZ MUZ-FH35VEHZ Item Smoothing (C61, C62) 600 µF/ 620 µF 420 V capacitor Diode module (DB61) 15 A 600 V (F61) T20AL250V Fuse (F701, F801, F901) T3.15AL250V Defrost heater 230 V 130 W...
NC-30 NC-30 NC-20 NC-20 NC-10 NC-10 1000 2000 4000 8000 1000 2000 4000 8000 BAND CENTER FREQUENCIES, Hz BAND CENTER FREQUENCIES, Hz MUZ-FH35VEHZ MUZ-FH50VEHZ FUNCTION SPL(dB(A)) LINE FUNCTION SPL(dB(A)) LINE COOLING COOLING HEATING HEATING NC-70 NC-70 NC-60 NC-60 NC-50 NC-50...
OUTLINES AND DIMENSIONS MUZ-FH25VEHZ Unit: mm REQUIRED SPACE MUZ-FH35VEHZ *1 100 mm or more when front and sides of the unit are clear Drain hole ø42 Air in Air in *2 When any 2 sides of left, right and rear of the unit are clear...
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MUZ-FH50VEHZ - Unit: mm REQUIRED SPACE *1 500 mm or more when front and sides of the unit are clear 417.5 Air in Air out 2-holes 10 21 *2 When any 2 sides of left, right and rear of the unit are clear Service panel Liquid refrigerant pipe joint Refrigerant pipe (flared) ø6.35...
PERFORMANCE CURVES MUZ-FH25VEHZ MUZ-FH35VEHZ MUZ-FH50VEHZ 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 11.4 10.3 Indoor intake air Wet-bulb temperature( ) Outdoor intake air Dry-bulb temperature (°C) Heating capacity (at Rated frequency) 15.9 19.8 26.9 14.6 18.3 24.8 13.4 16.8 22.7 12.2 15.2 20.7 11.0 13.7 18.6 12.2 16.5...
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The operational frequency The operational frequency of compressor (Hz) of compressor (Hz) of compressor (Hz) of compressor (Hz) MUZ-FH35VEHZ Correction of Cooling capacity Correction of Cooling input Correction of Heating capacity Correction of Heating input The operational frequency The operational frequency...
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MUZ-FH25VEHZ- MUZ-FH25VEHZ- (kgf/cm [Gauge])(MPa [Gauge]) (kgf/cm [Gauge])(MPa [Gauge]) ER4 ET1 Ambient temperature(°C) Ambient temperature(°C) Ambient humidity(%) Ambient humidity(%) MUZ-FH35VEHZ MUZ-FH50VEHZ (kgf/cm [Gauge])(MPa [Gauge]) (kgf/cm [Gauge])(MPa [Gauge]) Ambient temperature(°C) Ambient temperature(°C) Ambient humidity(%) Ambient humidity(%) NOTE: The unit of pressure has been changed to MPa on the international system of units (SI unit system) The conversion factor is: 1 (MPa [Gauge]) = 10.2 (kgf/cm...
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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 MUZ-FH25VEHZ- MUZ-FH25VEHZ- ER4 ET1 Ambient temperature (°C) Ambient temperature (°C) MUZ-FH35VEHZ MUZ-FH50VEHZ Ambient temperature (°C) Ambient temperature (°C) OBH625G...
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PERFORMANCE DATA COOL operation at Rated frequency MUZ-FH25VEHZ CAPACITY: 2.5 kW SHF: 0.95 INPUT: 485 W OUTDOOR DB (°C) INDOOR INDOOR DB (°C) WB (°C) INPUT INPUT INPUT INPUT 2.94 2.26 0.77 2.81 2.17 0.77 2.70 2.08 0.77 2.60 2.00 0.77 3.06 1.99...
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PERFORMANCE DATA COOL operation at Rated frequency MUZ-FH25VEHZ CAPACITY: 2.5 kW SHF: 0.95 INPUT: 485 W OUTDOOR DB (°C) INDOOR INDOOR DB (°C) WB (°C) INPUT INPUT INPUT 2.45 1.89 0.77 2.25 1.73 0.77 2.08 1.60 0.77 2.58 1.67 0.65 2.40 1.56 0.65...
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PERFORMANCE DATA COOL operation at Rated frequency MUZ-FH35VEHZ CAPACITY: 3.5 kW SHF: 0.84 INPUT: 820 W OUTDOOR DB (°C) INDOOR INDOOR DB (°C) WB (°C) INPUT INPUT INPUT INPUT 4.11 2.71 0.66 3.94 2.60 0.66 3.78 2.49 0.66 3.64 2.40 0.66...
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PERFORMANCE DATA COOL operation at Rated frequency MUZ-FH35VEHZ CAPACITY: 3.5 kW SHF: 0.84 INPUT: 820 W OUTDOOR DB (°C) INDOOR INDOOR DB (°C) WB (°C) INPUT INPUT INPUT 3.43 2.26 0.66 3.15 2.08 0.66 2.91 1.92 0.66 3.61 1.95 0.54 3.36...
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PERFORMANCE DATA COOL operation at Rated frequency MUZ-FH50VEHZ CAPACITY: 5.0 kW SHF: 0.73 INPUT: 1380 W OUTDOOR DB (°C) INDOOR INDOOR DB (°C) WB (°C) INPUT INPUT INPUT INPUT 5.88 3.23 0.55 1104 5.63 3.09 0.55 1159 5.40 2.97 0.55 1214 5.20 2.86...
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PERFORMANCE DATA COOL operation at Rated frequency MUZ-FH50VEHZ CAPACITY: 5.0 kW SHF: 0.73 INPUT: 1380 W OUTDOOR DB (°C) INDOOR INDOOR DB (°C) WB (°C) INPUT INPUT INPUT 4.90 2.70 0.55 1352 4.50 2.48 0.55 1435 4.15 2.28 0.55 1490 5.15 2.21 0.43...
ACTUATOR CONTROL MUZ-FH25VEHZ MUZ-FH35VEHZ MUZ-FH50VEHZ 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.
SERVICE FUNCTIONS MUZ-FH25VEHZ MUZ-FH35VEHZ MUZ-FH50VEHZ 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 finish temperature (°C) Jumper wire...
TROUBLESHOOTING MUZ-FH25VEHZ MUZ-FH35VEHZ MUZ-FH50VEHZ 11-1. 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 main unit first with the remote controller, and then after confirming the horizontal vane is closed, turn OFF the breaker and/or disconnect the power plug.
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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. Table of outdoor unit failure mode recall function Indoor/outdoor Outdoor unit POWER lamp Abnormal point LED indication unit failure Condition Remedy failure mode (Indoor unit) (Failure mode/protection) (Outdoor P.C. board) mode recall recall function function None (Normal) — — —...
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Indoor/outdoor Outdoor unit POWER lamp Abnormal point LED indication unit failure Condition Remedy failure mode mode recall (Indoor unit) (Failure mode/protection) (Outdoor P.C. board) recall function function 10-time blink Discharge temperature Temperature of discharge temperature • Refer to 11-5. "Check 2.5 seconds thermistor has been 50°C or less for of LEV".
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11-3. TROUBLESHOOTING CHECK TABLE Abnormal point/ Con- Symptom LED indication Condition Remedy dition Outdoor unit 1-time blink 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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Abnormal point/ Con- Symptom LED indication Condition Remedy dition Outdoor unit 7-time blink 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. TROUBLESHOOTING CRITERION OF MAIN PARTS MUZ-FH25VEHZ MUZ-FH35VEHZ MUZ-FH50VEHZ Part name Check method and criterion Figure Defrost thermistor (RT61) Measure the resistance with a tester. Refer to 11-6. “Test point diagram and voltage”, 1. “Inverter P.C. Fin temperature board”, for the chart of thermistor.
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11-5. TROUBLESHOOTING FLOW A How to check inverter/compressor Disconnect the connector between the compressor and the power module (IC700) (MUZ-FH25/35)/IGBT module (IC700) (MUZ-FH50). Check the voltage between terminals. See 11-5. “Check of open phase”. Are the voltages balanced? Replace the inverter P.C. board. Check the compressor.
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D Check of compressor winding ●Disconnect the connector between the compressor and the power module (IC700) (MUZ-FH25/35)/IGBT module (IC700) (MUZ-FH50), and measure the resistance between the compressor terminals. <<Measurement point>> At 3 points BLK-WHT * Measure the resistance between the lead wires at 3 points. BLK-RED 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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H Check of R.V. coil MUZ-FH25/35 * First of all, measure the resistance of R.V. coil to check if the coil is defective. Refer to 11-4. * In case CN721 is disconnected or R.V. coil is open, voltage is generated between the terminal pins of the connector although no signal is being transmitted to R.V.
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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 the compressor and the power module (IC700) (MUZ-FH25/35)/IGBT module (IC700) (MUZ-FH50). Rectify indoor/outdoor Turn ON power supply and press connecting wire. EMERGENCY OPERATION switch. Is there voltage 230 V AC Replace the indoor Does POWER lamp on the indoor between the indoor terminal electronic control P.C.
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MSZ-FH25VE MSZ-FH25VE2 K Check of LEV (Expansion valve) MSZ-FH35VE MSZ-FH35VE2 MSZ-FH50VE MSZ-FH50VE2 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.
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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 MUZ-FH25/35 Turn the 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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MUZ-FH50 Turn the power supply OFF. NOTE: Refer to the indoor unit service manual. 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 •...
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N Check of defrost heater 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 out- distance between the antennas and the door unit.
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11-6. TEST POINT DIAGRAM AND VOLTAGE 1. Inverter P.C. board MUZ-FH25VEHZ MUZ-FH35VEHZ Smoothing Smoothing R.V.coil Heater connector capacitor capacitor (CN721) (CN722) DB61 Back side of unit (C62) (C61) 230 VAC 260 - 370 V DC Fuse (F701) T3.15AL250V Fuse (F801) 230 V AC T3.15AL250V...
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MUZ-FH50VEHZ Fuse (F601) T3.15AL250V R.V. coil (CN602) 230V AC Heater (CN601) 230V AC Signal of out- door fan motor (CN931) LEV connector (CN724) Output to drive outdoor fan motor Defrost thermistor (CN932) /RT61 (CN671) Discharge temperature thermistor/RT62 Fuse (F901) (CN671) T3.15AL250V Outdoor heat exchanger temperature thermistor...
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2. Relay P.C. board MUZ-FH50VEHZ CN60 To inverter P.C. board CN681 (CN680) L68B(-) 10 V DC L68A(+) OBH625G...
Locking lever lever. Connector 12-1. MUZ-FH25VEHZ MUZ-FH35VEHZ : Indicates the visible parts in the photos/figures. : Indicates the invisible parts in the photos/figures. NOTE: Turn OFF the power supply before disassembly. OPERATING PROCEDURE PHOTOS/FIGURES 1. Removing the cabinet Photo 1 (1) Remove the screw fixing the service panel.
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OPERATING PROCEDURE PHOTOS/FIGURES 2. Removing the inverter assembly, inverter P.C. board Photo 3 (1) Remove the cabinet and panels. (Refer to section 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/FIGURES 5. Removing outdoor fan motor Photo 6 (1) Remove the cabinet and panels. (Refer to section 1.) (2) Disconnect the following connectors: <Inverter P.C. board> Outdoor heat CN931, CN932 (Fan motor) exchanger tempera- (3) Remove the propeller fan nut. ture thermistor (4) Remove the propeller fan.
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12-2. MUZ-FH50VEHZ NOTE: Turn OFF the power supply before disassembly. OPERATING PROCEDURE PHOTOS/FIGURES 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/FIGURES 2. Removing the inverter assembly, inverter P.C. board Photo 3 and relay P.C. board Screws of the (1) Remove the cabinet and panels. (Refer to section 1.) relay panel Inverter P.C Earth wires (2) Disconnect the lead wire to the reactor and the following con- board nectors: <Inverter P.C.
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OPERATING PROCEDURE PHOTOS/FIGURES 4. Removing the discharge temperature thermistor, Photo 5 defrost thermistor, outdoor heat exchanger tempera- Outdoor heat Ambient exchanger temperature ture thermistor and ambient temperature thermistor temperature thermistor thermistor (1) Remove the cabinet and panels. (Refer to section 1.) (2) Disconnect the lead wire to the reactor and the following connectors: <Inverter P.C.