SPLIT-TYPE, HEAT PUMP AIR CONDITIONERS OUTDOOR UNIT No. OBH489 SERVICE MANUAL utilized R410A Wireless type Models MUZ-FD25VA - MUZ-FD25VAH - MUZ-FD35VA - MUZ-FD35VAH - Indoor unit service manual MSZ-FD•VA Series (OBH488) CONTENTS 1. TECHNICAL CHANGES ····································3 2. PART NAMES AND FUNCTIONS······················3 3.
Specifications and rating conditions of main electric parts Model MUZ-FD25VA MUZ-FD25VAH MUZ-FD35VA MUZ-FD35VAH Item (CT) 20 A Current (CT761, CT781) 15 A transformer 620 + 420 V Smoothing capacitor (C61, C62, C63) (DB61) 15 A 600 V Diode module 25 A 600 V (DB65) (F61) T20AL250V...
OUTLINES AND DIMENSIONS MUZ-FD25VA Unit: mm MUZ-FD25VAH MUZ-FD35VA MUZ-FD35VAH REQUIRED SPACE Basically open 100 mm or more without any obstruction in front and on both sides of the unit. Drain hole [42 (FD25/35VA) Drain hole [33 (FD25/35VAH) Air in Air in Open two sides of left, right, or rear side.
PERFORMANCE CURVES MUZ-FD25VA MUZ-FD35VA MUZ-FD25VAH MUZ-FD35VAH 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.
Total input (cooling) Indoor intake air Wet-bulb temperature(:) Outdoor intake air Dry-bulb temperature (:) Heating capacity 17.3 20.9 16.0 19.3 14.6 17.7 13.3 16.1 12.0 14.5 10.6 12.9 11.3 Outdoor intake air Wet-bulb temperature (:) Total input(heating) 17.3 20.9 16.0 19.3 14.6 17.7...
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8-2. Capacity and input correction by operational frequency of compressor MUZ-FD25VA MUZ-FD25VAH Correction of Heating input Correction of Cooling input Correction of Cooling capacity Correction of Heating capacity 150(Hz) 150(Hz) 150(Hz) 150(Hz) The operational frequency of compressor The operational frequency of compressor The operational frequency of compressor The operational frequency of compressor MUZ-FD35VA...
8-4. Outdoor low pressure and outdoor unit current COOL operation Relative humidity(%) Dry-bulb temperature(:) 1 Both indoor and outdoor unit are under the same temperature/humidity condition. 2 Operation : TEST RUN OPERATION (refer to 8-3.) Outdoor low pressure MUZ-FD25VA MUZ-FD25VAH MUZ-FD35VA MUZ-FD35VAH 35(˚C)
ACTUATOR CONTROL MUZ-FD25VA MUZ-FD35VA MUZ-FD25VAH MUZ-FD35VAH 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-FD25VA MUZ-FD35VA MUZ-FD25VAH MUZ-FD35VAH 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 finish temperature (:) soldered (Initial setting) none...
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. This mode is very useful when the unit needs to be repaired for the abnormality which doesn't recur.
2. Flow chart of the detailed outdoor unit failure mode recall function Operational procedure The outdoor unit might be abnormal. Confirm if outdoor unit is abnormal according to the following procedures. Confirm that the remote controller is in the failure mode recall function.
3. Outdoor unit failure mode table Indoor/outdoor Outdoor unit Abnormal point POWER lamp LED indication Condition Correspondence unit failure mode failure mode (Indoor unit) (Failure mode / protection) (Outdoor P.C. board) recall function recall function None (Normal) Outdoor power system Overcurrent protection stop is •Reconnect connectors.
11-3. Troubleshooting check table Symptom LED indication Abnormal point/ Condition Condition Correspondence Overcurrent protection stop is continuously performed 3 times · Reconnect connector of compressor. 1-time flash every Outdoor power Outdoor unit · Refer to 11-5.A "How to check within 1 minute after the compressor gets started, or failure of 2.5 seconds system does not...
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11-4. Trouble criterion of main parts MUZ-FD25VA MUZ-FD35VA MUZ-FD25VAH MUZ-FD35VAH Part name Check method and criterion Figure Defrost thermistor Measure the resistance with a tester. (RT61) Ambient temperature Refer to 11-7. "Test point diagram and voltage", 1. "Inverter P.C. board", thermistor (RT65) the chart of thermistor.
11-5. Troubleshooting flow POWER lamp flashes 5-times. Outdoor unit does not operate. How to check inverter/ compressor Disconnect the connector (CN61) between compressor and the intelligent power module (IPM). Check the voltage See 11-5.B “Check of open phase” . between terminals. Are the voltages Replace the inverter P.C.
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Check of compressor winding Disconnect the connector (CN61) between the compressor and intelligent power module, and measure the resistance between the compressor terminals. <<Measurement point>> at 3 points BLK-WHT w Measure the resistance between the BLK-RED lead wires at 3 points. WHT-RED <<Judgement>>...
POWER lamp flashes 6-time. The thermistors in the outdoor unit are abnormal. 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 thermistor normal? (Refer to 11-6.1.) When RT64 is abnormal, replace the inverter P.C.
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Outdoor fan motor does not operate. Check of outdoor fan motor Disconnect CN932 from the inverter P.C. board, and measure the resistance of the outdoor fan motor. Is the outdoor fan motor Replace the outdoor fan normal? motor. (Refer to 11-4.) Replace the inverter P.C.
Heating/Cooling does not work sufficiently. Check of LEV (Expansion valve) Turn ON the power supply. < Preparation of the remote controller > 1 While pressing both OPERATION SELECT button and TOO COOL button on the remote controller at the same time, press RESET button. 2 First, release RESET button.
Outdoor fan motor does not operate , or stops immediately after starting up. Check of inverter P.C. board Check the outdoor fan motor. (Refer to11-5.I.) Is the fuse (F901) blown on the inverter P.C. board? Inverter P.C.board Check the connection of the connector (Solder side) (CN932) of outdoor fan motor.
• Unit cannot operate neither by the remote controller nor by EMERGENCY OPERATION switch. Indoor unit does not operate. • POWER lamp flashes ON and OFF every 0.5-second. Outdoor unit doesn’t operate. How to check miswiring and serial signal error (when outdoor unit does not work) Turn OFF the power supply.
Electromagnetic noise enters into TV sets or radios Is the unit earthed? Earth the unit. Is the distance between the Extend the distance between antennas and the indoor the antennas and the indoor unit within 3 m, or is the unit, and/or the antennas and distance between the the outdoor unit.
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Outdoor base gets frozen. Check of defrost heater MUZ-FD25VAH MUZ-FD35VAH 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) Are both ambient temperature thermistor and circuit of defrost heater securely connected to connectors? In HEAT mode, for more than 5 minutes, let the ambient temperature thermistor continue to read 5 : or below, and let...
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11-6. Test point diagram and voltage 1. Inverter P.C. board MUZ-FD25VA MUZ-FD35VA MUZ-FD25VAH MUZ-FD35VAH Smoothing Smoothing Smoothing Fuse(F701)2 Heater capacitor capacitor capacitor DB61 Back side of unit 50 V 3.15 A connector (C62) (C63) (C61) DC260 ~300 V (CN722) Fuse(F801)2 MUZ-FD•VAH AC230V 50 V 3.15 A...
DISASSEMBLY INSTRUCTIONS <"Terminal with locking mechanism" Detaching points> The terminal which has the locking mechanism can be detached as shown below. There are two 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.) (2) Disconnect the lead wire to the reactor and the following Screws of the connectors; relay panel <Inverter P.C. board> CN721 (R.V.coil) CN722 (Defrost heater) CN932 (Fan motor)
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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 connectors for outdoor fan motor. (3) Remove the propeller nut. (See Photo 7.) (4) Remove the propeller. (See Photo 7.) Outdoor heat (5) Remove the screws fixing the fan motor.
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HEAD OFFICE: TOKYO BLDG., 2-7-3, MARUNOUCHI, CHIYODA-KU, TOKYO 100-8310, JAPAN C C Copyright 2007 MITSUBISHI ELECTRIC ENGINEERING CO.,LTD New publication, effective Aug. 2007 Distributed in Aug. 2007. No. OBH489 6 Specifications subject to change without notice. Made in Japan...
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