SPLIT-TYPE AIR CONDITIONERS OUTDOOR UNIT No. OBH625 SERVICE MANUAL utilized R410A Models MUZ-FH25VEHZ MUZ-FH35VEHZ Indoor unit service manual MSZ-FH•VE Series (OBH623) CONTENTS 1. TECHNICAL CHANGES ··································· 3 2. PART NAMES AND FUNCTIONS ····················· 3 3. SPECIFICATION ················································ 4 4. NOISE CRITERIA CURVES ······························ 6 5.
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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.
TECHNICAL CHANGES MUZ-FH25VEHZ - MUZ-FH35VEHZ - 1. New model PART NAMES AND FUNCTIONS MUZ-FH25VEHZ MUZ-FH35VEHZ Air inlet (back and side) Piping Drain hose Air outlet Drain outlet OBH625...
SPECIFICATION Outdoor model MUZ-FH25VEHZ MUZ-FH35VEHZ Power supply Single phase, 230 V, 50 Hz Cooling 2.5 (0.8 - 3.5) 3.5 (0.8 - 4.0) Capacity Rated frequency (Min.-Max.) Heating 3.2 (1.0 - 6.3) 4.0 (1.0 - 6.6) Breaker Capacity Cooling Power input 1 (Total)
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Specifi cations and rated conditions of main electric parts Model MUZ-FH25VEHZ MUZ-FH35VEHZ Item Smoothing (C61, C62) 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...
OUTLINES AND DIMENSIONS MUZ-FH25VEHZ Unit: mm MUZ-FH35VEHZ REQUIRED SPACE 100 mm or more Drain hole ø33 Air in Air in 2 holes 10 X 21 Service panel Air out 22.3 Liquid refrigerant pipe joint Handle Refrigerant pipe (flared) ø6.35 Gas refrigerant pipe joint Refrigerant pipe (flared) ø9.52...
PERFORMANCE CURVES MUZ-FH25VEHZ MUZ-FH35VEHZ 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 Indoor intake air Wet-bulb temperature( ) Outdoor intake air Dry-bulb temperature (°C) Heating capacity (at Rated frequency) 15.9 19.8 14.6 18.3 13.4 16.8 12.2 15.2 11.0 13.7 12.2 10.7 Outdoor intake air Wet-bulb temperature (°C) Total input (Heating : at Rated frequency 15.9...
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8-2. CAPACITY AND INPUT CORRECTION BY OPERATIONAL FREQUENCY OF COMPRESSOR MUZ-FH25VEHZ 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)
COOL operation Dry-bulb temperature (°C) Relative humidity (%) Both indoor and outdoor unit are under the same temperature/ humidity condition. Operation: TEST RUN OPERATION (Refer to 8-3.) Outdoor low pressure MUZ-FH25VEHZ MUZ-FH35VEHZ (kgf/cm [Gauge])(MPa [Gauge]) (kgf/cm [Gauge])(MPa [Gauge]) Ambient temperature(°C) Ambient temperature(°C)
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PERFORMANCE DATA COOL operation a t 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...
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PERFORMANCE DATA COOL operation a t 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...
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PERFORMANCE DATA COOL operation a t 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 4.29...
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PERFORMANCE DATA COOL operation a t 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 1.81...
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PERFORMANCE DATA HEAT operation at Rated frequency MUZ-FH25VEHZ CAPACITY: 3.2 kW INPUT: 580 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...
ACTUATOR CONTROL MUZ-FH25VEHZ MUZ-FH35VEHZ 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 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.) Jumper wire Defrost fi nish temperature (°C)
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.
2. Flow chart of the detailed outdoor unit failure mode recall function Operational procedure The outdoor unit might be abnormal. Confi rm if outdoor unit is abnormal according to the following procedures. Confi rm that the remote controller is in the failure mode recall function. 1.
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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11-4. TROUBLE CRITERION OF MAIN PARTS MUZ-FH25VEHZ MUZ-FH35VEHZ 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.
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 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 outdoor 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 intelligent power module. Rectify indoor/outdoor Turn ON power supply and press connecting wire. EMERGENCY OPERATION switch. Is there voltage 230 VAC Replace the indoor Does POWER lamp on the indoor between the indoor terminal electronic control P.C.
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K Check of LEV (Expansion valve) 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 two buttons for another 3 sec- onds.
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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...
N 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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O 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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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) DB61 (CN722) Back side of unit (C62) (C61) 230 VAC 260 - 370 VDC Fuse (F701) T3.15AL250V Fuse (F801) 230 VAC T3.15AL250V...
Pull the terminal while pull out the terminal pushing the locking slowly. Locking lever lever. Connector 12-1. MUZ-FH25VEHZ MUZ-FH35VEHZ NOTE: Turn OFF power supply before disassembly. OPERATING PROCEDURE PHOTOS 1. Removing the cabinet Photo 1 (1) Remove the screw fixing the service panel.
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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 (1) Remove the cabinet and panels. (Refer to 1.) (2) Disconnect the following connectors: <Inverter P.C. board> Outdoor heat CN931, CN932 (Fan motor) exchanger tempera- (3) Remove the propeller nut. ture thermistor (4) Remove the propeller.