SPLIT-TYPE, HEAT PUMP AIR CONDITIONERS OUTDOOR UNIT No. OBH469 SERVICE MANUAL utilized R410A Wireless type Models MUZ-GC25VA - MUZ-GC25VAH - MUZ-GC35VA - MUZ-GC35VAH - Indoor unit service manual MSZ-GC•VA Series (OBH468) CONTENTS 1. TECHNICAL CHANGES ····································2 2. PART NAMES AND FUNCTIONS······················2 3.
OUTLINES AND DIMENSIONS MUZ-GC25VA Unit: mm REQUIRED SPACE MUZ-GC25VAH Basically open 100 mm or more without any obstruction in front and on both sides of the unit. 381.5 Air in Air in Open two sides of left, right, or rear side. 2 holes 10 X 16 Air out Service panel...
PERFORMANCE CURVES MUZ-GC25VA MUZ-GC35VA MUZ-GC25VAH MUZ-GC35VAH The standard data contained in these 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.
Total input (cooling) 10.6 Outdoor intake air Dry-bulb temperature (:) Heating capacity 20.9 27.5 19.3 25.4 17.7 23.3 16.1 21.2 14.5 19.1 12.9 16.9 11.3 14.8 12.7 10.6 Outdoor intake air Wet-bulb temperature (:) Total input(heating) 20.9 27.5 19.3 25.4 17.7 23.3 16.1...
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8-2. Capacity and input correction by operational frequency of compressor MUZ-GC25VA MUZ-GC25VAH Correction of Heating total input Correction of Cooling capacity Correction of Cooling total input 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-GC35VA...
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-GC25VA MUZ-GC35VA MUZ-GC25VAH MUZ-GC35VAH NOTE :...
ACTUATOR CONTROL MUZ-GC25VA MUZ-GC35VA MUZ-GC25VAH MUZ-GC35VAH 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-GC25VA MUZ-GC35VA MUZ-GC25VAH MUZ-GC35VAH 10-1. CHANGE IN DEFROST SETTING <JS> When the JS wire of the outdoor Inverter P.C. board is cut/ soldered, the defrost finish temperature is changed. (Refer to 11-6-1.) Defrost finish temperature (:) Jumper wire MUZ-GC25VA MUZ-GC25VAH MUZ-GC35VA...
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 (11-4.) 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 The upper lamp of Indoor/outdoor Outdoor unit Abnormal point LED indication Condition Correspondence OPERATION INDICATOR unit failure mode failure mode (Failure mode / protection) (Outdoor P.C. board) recall function recall function lamp(Indoor unit) None (Normal) Outdoor power system Over current protection stop is •Reconnect connectors.
11-3. Troubleshooting check table Symptom LED indication Abnormal point/ Condition Condition Correspondence Over current protection stop is continuously performed three · Reconnect connector of compressor. 1-time flash every Outdoor power Outdoor unit · Refer to 11-5.A "How to check times within 1 minute after the compressor gets started, or 2.5 seconds system does not...
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11-4. Trouble criterion of main parts MUZ-GC25VA MUZ-GC35VA MUZ-GC25VAH MUZ-GC35VAH Part name Check method and criterion Figure Defrost thermistor Measure the resistance with a tester. (RT61) Refer to 11-7. "Test point diagram and voltage", 1. "Inverter P.C. board", Ambient temperature the chart of thermistor.
11-5. Troubleshooting flow When OPERATION INDICATOR 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.
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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>>...
When OPERATION INDICATOR lamp flashes 6-time. The thermistors in the outdoor unit are abnormal. Check of outdoor thermistors Disconnect the connectors CN641, CN642 and CN643 from the inverter P.C. board. Defrost thermistor RT61 (Check the characteristics of each thermistor.) Measure the resistance between CN641 1 and 2.
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Outdoor fan motor does not operate. Check of outdoor fan motor MUZ-GC25VA MUZ-GC25VAH Check the resistance of fan motor. (Refer to 11-4.) Replace the outdoor Is the resistance of fan fan motor. motor normal? Disconnect the connector CN771 on inverter P.C. board.
Inverter does not operate. Check of power supply Disconnect the connector (CN61) between compressor and intelligent power module. Turn ON power supply and press Rectify indoor/ outdoor EMERGENCY OPERATION connecting wire. switch. Does the upper lamp of Is there voltage 230V AC Replace the indoor OPERATION INDICATOR between the indoor...
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.
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Outdoor fan motor does not operate , or stops immediately after starting up. Check of inverter P.C. board MUZ-GC35VA MUZ-GC35VAH 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 connectors. (Solder side) (CN931, CN932) of outdoor fan motor.
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• When unit cannot operate neither by the remote controller nor by EMERGENCY OPERATION switch. Indoor unit does not operate. • When OPERATION INDICATOR lamp flashes ON and OFF in every 0.5-seconds. Outdoor unit doesn’t operate. How to check mis-wiring and serial signal error (when outdoor unit does not work) Is there rated voltage in Check the power 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 3m, 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-GC25VAH MUZ-GC35VAH 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-GC25VA MUZ-GC25VAH Smoothing capacitor Fuse Smoothing capacitor Varistor Varistor (C62) (F801) (C61) (NR62) (NR61) Varistor 230V AC Back side of unit (NR63) DB61 DB61 280V ~ 370V Fuse Output to (F701) drive compressor...
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1. Inverter P.C. board MUZ-GC35VA MUZ-GC35VAH Back side of unit 230V AC Smoothing capacitor Smoothing capacitor Smoothing capacitor DB61 DB61 (C63C) (C63B) (C63A) 280V ~ 370V FUSE (F801) FUSE (F901) LED monitor lamp Output to drive compressor (LDW, LDV, LDU) 1(+) 2(+) 3(+)
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2. Power P.C. board MUZ-GC35VA MUZ-GC35VAH Back side of unit Front side of unit Varistor Varistor Varistor (NR63) (NR62) (NR64) 230V AC R.V.coil(CN721) 230V AC Connecting wire with FUSE 230V AC inverter P.C.board (F71) Heater connector (CN726) (CN722) MUZ-GC35VAH...
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 Photo 3 2. Removing the inverter assembly, inverter P.C. board Screws of the (1) Remove the cabinet and panels. (Refer to 1.) relay panel (2) Disconnect the earth wires (See Photo 3.), the lead wire to the reactor and the following connectors; Screw of <Inverter P.C.
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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.) (5) Remove the screws fixing the fan motor.
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12-2. MUZ-GC35VA MUZ-GC35VAH NOTE : Turn OFF power supply before disassembling. OPERATING PROCEDURE PHOTOS Photo 1 1. Removing the cabinet (1) Remove the screw fixing the service panel. (See Photo 2.) (2) Pull down the service panel and remove it. (See Photo 2.) Screws Screw of of the...
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OPERATING PROCEDURE PHOTOS 2. Removing the inverter assembly, inverter P.C. board Photo 3 and power P.C. board (1) Remove the cabinet and panels. (Refer to 1.) Screws of the (2) Disconnect the earth wires (See Photo 3.), the lead wire to relay panel the reactor and the following connectors;...
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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.) (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 Distributed in Jan. 2007. No. OBH469 6 New publication, effective Jan. 2007 Made in Japan Specifications subject to change without notice.