Service manual

ManualsBrandsMitsubishi ManualsAir ConditionerMUZ-A12YVH

SERVICE MANUAL

CONTENTS

1. TECHNICAL CHANGES ····································2

2. PART NAMES AND FUNCTIONS······················5

3. SPECIFICATION·················································5

4. NOISE CRITERIA CURVES·······························7

5. OUTLINES AND DIMENSIONS ·························8

6. WIRING DIAGRAM ············································9

7. REFRIGERANT SYSTEM DIAGRAM ··············11

8. PERFORMANCE CURVES······························12

9. ACTUATOR CONTROL····································21

10. SERVICE FUNCTIONS·····································22

11. TROUBLESHOOTING······································22

12. DISASSEMBLY INSTRUCTIONS·····················34

13. PARTS LIST······················································38

Wireless type

Models

No. OB328

REVISED EDITION-A

SPLIT-TYPE, HEAT PUMP AIR CONDITIONERS

MUZ-A09YV -

MUZ-A12YV -

MUZ-A09YVH -

MUZ-A12YVH -

MUZ-A09YV -

MUZ-A12YV -

MUZ-A09YVH -

MUZ-A12YVH -

Indication of

model name

NOTE:

This service manual describes technical data of the outdoor units.

•As for indoor units MSZ-A09YV- and MSZ-A12YV- , refer to the service manual OB327.

•As for indoor unit MCFZ-A12WV- , refer to the service manual OB344.

E1E1

HFC

utilized

R410A

Revision A:

● MUZ-A12YV- and MUZ-A12YVH-

can be connected to MCFZ-A12WV- .

● Some mistakes were corrected.

E1E1

Please void OB328.

OB328 A--1qxp 04.4.26 4:49 PM Page 1

Mitsubishi Electric ilmalämpöpumput korjaa ja huoltaa pääkaupunkiseudulla: Jäähdytinpalvelu RefGroup Oy

www.ilmalämpöpumput.com

Summary of content (40 pages)

PAGE 1
OB328 A--1qxp 04.4.26 4:49 PM Page 1 Mitsubishi Electric ilmalämpöpumput korjaa ja huoltaa pääkaupunkiseudulla: Jäähdytinpalvelu RefGroup Oy Revision A: ● MUZ-A12YV- E1 and MUZ-A12YVH- E1 can be connected to MCFZ-A12WV- E1 . ● Some mistakes were corrected. SPLIT-TYPE, HEAT PUMP AIR CONDITIONERS Please void OB328. HFC utilized SERVICE MANUAL No.
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OB328 A--1qxp 04.4.26 4:49 PM Page 2 Mitsubishi Electric ilmalämpöpumput korjaa ja huoltaa pääkaupunkiseudulla: Jäähdytinpalvelu RefGroup Oy Revision A: •MUZ-A12YV- E1 and MUZ-A12YVH•Some mistakes were corrected. 1 E1 can be connected to MCFZ-A12WV- E1 . TECHNICAL CHANGES INFORMATION FOR THE AIR CONDITIONER WITH R410A REFRIGERANT • This room air conditioner adopts an HFC refrigerant (R410A) which never destroys the ozone layer.
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OB328 A--1qxp 04.4.26 4:49 PM Page 3 Mitsubishi Electric ilmalämpöpumput korjaa ja huoltaa pääkaupunkiseudulla: Jäähdytinpalvelu RefGroup Oy Conversion chart of refrigerant temperature and pressure (MPa [Gauge]) 4.0 Saturated liquid pressure 3.5 R410A 3.0 R22 2.5 2.0 NOTE : The unit of pressure has been changed to MPa on the international system of units(SI unit system). 1.5 1.0 f [Gauge]) The conversion factor is: 1(MPa [Gauge]) =10.2(kgf/f 0.5 0.0 -0.
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OB328 A--1qxp 04.4.26 4:49 PM Page 4 Mitsubishi Electric ilmalämpöpumput korjaa ja huoltaa pääkaupunkiseudulla: Jäähdytinpalvelu RefGroup Oy 2 Flaring work and flare nut Flaring work for R410A pipe differs from that for R22 pipe. For details of flaring work, refer to Installation manual “FLARING WORK”. Dimension of flare nut Pipe diameter mm R410A R22 6.35 17 17 9.52 22 22 12.7 26 24 3.
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OB328 A--1qxp 04.4.
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OB328 A--1qxp 04.4.26 4:49 PM Page 6 Mitsubishi Electric ilmalämpöpumput korjaa ja huoltaa pääkaupunkiseudulla: Jäähdytinpalvelu RefGroup Oy Specifications and rating conditions of main electric parts OUTDOOR UNIT Model Item MUZ-A09YV - E1 MUZ-A09YVH - MUZ-A12YV - E1 (CT) ETQ19Z53AY Current transformer (CT761, CT781) ETQ19Z71AY Smoothing capacitor (C62A, C62B, C61B) 680+ 420V (C65) 1.
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OB328 A--1qxp 04.4.
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OB328 A--1qxp 04.4.26 4:49 PM Page 8 Mitsubishi Electric ilmalämpöpumput korjaa ja huoltaa pääkaupunkiseudulla: Jäähdytinpalvelu RefGroup Oy 5 OUTLINES AND DIMENSIONS MUZ-A09YV - E1 MUZ-A09YVH - E1 MUZ-A12YV - E1 MUZ-A12YVH - E1 Unit: mm OUTDOOR UNIT REQUIRED SPACE Basically open 100mm or more without any obstruction in front and on both sides of the unit.
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www.ilmalämpöpumput.com 9 1 2 NAME DB65 + RT61RT62 RT65 CN641 1 2 3 4 NAME SR61 FIN TEMPERATURE THERMISTOR 21S4 R.V. COIL DISCHARGE TEMPERATURE THERMISTOR X63,X64 RELAY POWER TRANSISTOR MODULE RT64 TRANSFORMER C N 7 2 4 6 LEV CN61 RED MC WHT W BLK V U NOTE:1. About the indoor side electric wiring refer to the indoor unit electric wiring diagram for servicing. 2.Use copper conductors only. (For field wiring) 3. Symbols below indicate.
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26H H BLU 12V www.ilmalämpöpumput.com 10 BLK YLW RED SYMBOL REACTOR EXPANSION VALVE COIL C N 7 2 5 + IC801 R61 T801 F801 1 2 3 4 RT61RT62 1 2 RT65 NAME RT64 1 2 CN642 TB TRANSFORMER SWITCHING POWER TRANSISTOR FIN TEMPERATURE THERMISTOR 26H AMBIENT TEMPERATURE THERMISTOR INTELLIGENT POWER DEVICE RT64 POWER TRANSISTOR MODULE RT65 IC801 IPM HEATER PROTECTOR R.V.
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OB328 A--1qxp 04.4.26 4:49 PM Page 11 Mitsubishi Electric ilmalämpöpumput korjaa ja huoltaa pääkaupunkiseudulla: Jäähdytinpalvelu RefGroup Oy 7 REFRIGERANT SYSTEM DIAGRAM MUZ-A09YV - E1 MUZ-A09YVH - E1 MUZ-A12YV - E1 MUZ-A12YVH - E1 OUTDOOR UNIT Unit:mm 4-way valve Refrigerant pipe [9.
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OB328 A--1qxp 04.4.
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OB328 A--1qxp 04.4.26 4:49 PM Page 13 Mitsubishi Electric ilmalämpöpumput korjaa ja huoltaa pääkaupunkiseudulla: Jäähdytinpalvelu RefGroup Oy INDOOR UNIT OUTDOOR UNIT MSZ type MCFZ type Air out Wet and dry-bulb thermometers Air in 7.3 8.2 8.7 6.8 7.6 8.0 6.3 7.0 7.3 5.7 6.4 6.6 5.2 5.8 5.9 Wet and dry-bulb thermometers Indoo r inta MCFZ-A12WV - E1 MUZ-A12YV - E1 MUZ-A12YVH - E1 Rated frequency 69Hz 5.3 19.6 23.4 18.1 19.5 21.5 16.6 17.8 19.5 15.1 16.0 17.6 13.6 14.
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OB328 A--1qxp 04.4.26 4:49 PM Page 14 Mitsubishi Electric ilmalämpöpumput korjaa ja huoltaa pääkaupunkiseudulla: Jäähdytinpalvelu RefGroup Oy MUZ-A09YV - E1 MUZ-A09YVH - E1 MUZ-A09YV - E1 MUZ-A09YVH - E1 Correction of Cooling total input 1.5 1.5 1.0 1.0 0.5 Correction of Heating total input 2.0 Correction of Heating capacity 2.0 Input correction factors Input correction factors Capacity correction factors 0.
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OB328 A--1qxp 04.4.26 4:49 PM Page 15 Mitsubishi Electric ilmalämpöpumput korjaa ja huoltaa pääkaupunkiseudulla: Jäähdytinpalvelu RefGroup Oy OUTDOOR LOW PRESSURE AND OUTDOOR UNIT CURRENT COOL operation Dry-bulb temperature Relative humidity(%) 20 50 25 60 30 70 1 Both indoor and outdoor unit are under the same temperature/humidity condition. 2 Air flow : High speed 3 Operational frequency : 57Hz(MUZ-A09YV, MUZ-A09YVH) 69Hz(MUZ-A12YV, MUZ-A12YVH) ( 1.2 10 1.0 8 0.8 6 0.6 4 2 1.
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OB328 A--1qxp 04.4.26 4:49 PM Page 16 Mitsubishi Electric ilmalämpöpumput korjaa ja huoltaa pääkaupunkiseudulla: Jäähdytinpalvelu RefGroup Oy PERFORMANCE DATA COOL operation Rated frequency 57Hz MSZ-A09YV - E1 CAPACITY:2.5(kW) : MUZ-A09YV - E1 MUZ-A09YVH - E1 SHF:0.79 INPUT:670(W) OUTDOOR INDOOR INDOOR DB(:) WB(:) 21 21 22 22 22 23 23 23 24 24 24 24 25 25 25 25 26 26 26 26 26 27 27 27 27 27 28 28 28 28 28 29 29 29 29 29 30 30 30 30 30 31 31 31 31 31 32 32 32 32 32 NOTE 21 Q SHC SHF INPUT 18 2.
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OB328 A--1qxp 04.4.26 4:49 PM Page 17 Mitsubishi Electric ilmalämpöpumput korjaa ja huoltaa pääkaupunkiseudulla: Jäähdytinpalvelu RefGroup Oy PERFORMANCE DATA COOL operation Rated frequency 57Hz MSZ-A09YV - E1 CAPACITY:2.5(kW) INDOOR INDOOR DB (:) WB (:) 21 21 22 22 22 23 23 23 24 24 24 24 25 25 25 25 26 26 26 26 26 27 27 27 27 27 28 28 28 28 28 29 29 29 29 29 30 30 30 30 30 31 31 31 31 31 32 32 32 32 32 NOTE Q : MUZ-A09YV - E1 MUZ-A09YVH - E1 SHF:0.79 INPUT:670(W) 35 SHC SHF INPUT 18 2.45 1.49 0.
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OB328 A--1qxp 04.4.26 4:49 PM Page 18 Mitsubishi Electric ilmalämpöpumput korjaa ja huoltaa pääkaupunkiseudulla: Jäähdytinpalvelu RefGroup Oy PERFORMANCE DATA COOL operation Rated frequency 69Hz MSZ-A12YV - E1 MCFZ-A12WV - E1 CAPACITY:3.5(kW) SHF:0.
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OB328 A--1qxp 04.4.26 4:49 PM Page 19 Mitsubishi Electric ilmalämpöpumput korjaa ja huoltaa pääkaupunkiseudulla: Jäähdytinpalvelu RefGroup Oy PERFORMANCE DATA COOL operation Rated frequency 69Hz MSZ-A12YV - E1 MCFZ-A12WV - E1 CAPACITY:3.5(kW) INDOOR INDOOR DB (:) WB (:) 21 21 22 22 22 23 23 23 24 24 24 24 25 25 25 25 26 26 26 26 26 27 27 27 27 27 28 28 28 28 28 29 29 29 29 29 30 30 30 30 30 31 31 31 31 31 32 32 32 32 32 NOTE SHF:0.
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OB328 A--1qxp 04.4.26 4:49 PM Page 20 Mitsubishi Electric ilmalämpöpumput korjaa ja huoltaa pääkaupunkiseudulla: Jäähdytinpalvelu RefGroup Oy PERFORMANCE DATA HEAT operation MSZ-A09YV - E1 CAPACITY:3.2(kW) INDOOR DB(:) 15 21 26 : MUZ-A09YV - E1 MUZ-A09YVH - E1 Rated frequency 75Hz INPUT:840(W) OUTDOOR WB(:) -10 -5 0 5 10 15 20 Q INPUT Q INPUT Q INPUT Q INPUT Q INPUT Q INPUT Q INPUT 2.02 546 2.43 655 2.85 739 3.26 798 3.68 848 4.06 874 4.48 890 1.92 588 2.30 697 2.72 773 3.10 832 3.52 874 3.
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OB328 A--1qxp 04.4.26 4:49 PM Page 21 Mitsubishi Electric ilmalämpöpumput korjaa ja huoltaa pääkaupunkiseudulla: Jäähdytinpalvelu RefGroup Oy 9 ACTUATOR CONTROL MUZ-A09YV - E1 MUZ-A09YVH - E1 MUZ-A12YV - E1 MUZ-A12YVH - E1 9-1. Outdoor fan motor control The AC fan motor turns ON/OFF, interlocking with the compressor. [ON] The AC fan motor turns ON 5 seconds before the compressor starts up. [OFF] The AC fan motor turns OFF 15 seconds after the compressor has stopped running.
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OB328 A--1qxp 04.4.26 4:49 PM Page 22 Mitsubishi Electric ilmalämpöpumput korjaa ja huoltaa pääkaupunkiseudulla: Jäähdytinpalvelu RefGroup Oy 10 SERVICE FUNCTIONS MUZ-A09YV - E1 MUZ-A09YVH - E1 MUZ-A12YV - E1 MUZ-A12YVH - E1 CHANGE IN DEFROST SETTING When the JS wire of the outdoor Inverter P.C. board is cut/ soldered, the defrost finish temperature is changed. (Refer to page 32.
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OB328 A--1qxp 04.4.26 4:49 PM Page 23 Mitsubishi Electric ilmalämpöpumput korjaa ja huoltaa pääkaupunkiseudulla: Jäähdytinpalvelu RefGroup Oy 11-2. Instruction of troubleshooting Start Indoor unit operates. Outdoor unit doesn't operate. Outdoor unit operates in only Test Run operation. Outdoor unit doesn't operate even in Test Run operation. Indoor unit operates. Outdoor unit doesn't operate normally. Unit doesn't operate normal operation in COOL or HEAT mode.
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OB328 A--1qxp 04.4.26 4:49 PM Page 24 Mitsubishi Electric ilmalämpöpumput korjaa ja huoltaa pääkaupunkiseudulla: Jäähdytinpalvelu RefGroup Oy 1. Troubleshooting check table NOTE 1. The location of LED is illustrated at the right figure. Refer to page 32. 2. LED lights up during normal operation. No. 1 Symptom Outdoor unit does not operate LED indication Abnormal point/ Condition 1-time flash every Outdoor power 2.
PAGE 25
OB328 A--1qxp 04.4.26 4:49 PM Page 25 Mitsubishi Electric ilmalämpöpumput korjaa ja huoltaa pääkaupunkiseudulla: Jäähdytinpalvelu RefGroup Oy 2. Trouble criterion of main parts MUZ-A12YV - E1 MUZ-A12YVH - E1 Part name Discharge temperature thermistor(RT62) Fin temperature thermistor(RT64) Measure the resistance with a tester. (Part temperature –15˚C ~ 40˚C) Normal 5 k" ~ 65 k" Abnormal Open or short-circuit Measure the resistance with a tester.
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OB328 A--1qxp 04.4.26 4:49 PM Page 26 Mitsubishi Electric ilmalämpöpumput korjaa ja huoltaa pääkaupunkiseudulla: Jäähdytinpalvelu RefGroup Oy When OPERATION INDICATOR lamp flashes 5-time. Outdoor unit does not operate. A How to check inverter/ compressor Disconnect the connector (CN61) between compressor and power transistor module (IPM). Check the voltage between terminals. Are the voltages balanced? See B “Check of open phase” on page 26. No Check the resistance of power transistor module.
PAGE 27
OB328 A--1qxp 04.4.26 4:49 PM Page 27 Mitsubishi Electric ilmalämpöpumput korjaa ja huoltaa pääkaupunkiseudulla: Jäähdytinpalvelu RefGroup Oy D Check of compressor Start E "Check of compressor winding" on page 27. Is the compressor normal? No Replace the compressor. Yes F "Check of compressor operation time" on page 27. Does the compressor operate continuously? Yes Is the compressor operation time more than 10 seconds? No No Replace the compressor. Yes Ok Check the refrigerant circuit.
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OB328 A--1qxp 04.4.26 4:49 PM Page 28 Mitsubishi Electric ilmalämpöpumput korjaa ja huoltaa pääkaupunkiseudulla: Jäähdytinpalvelu RefGroup Oy When OPERATION INDICATOR lamp flashes 6-time. The thermistors in the outdoor unit are abnormal. G Check of outdoor thermistors Defrost thermistor RT61 Disconnect the connectors CN641, CN642 and CN643 from the inverter P.C. board. (Check the characteristics of each thermistor.) Measure the resistance between CN641 1 and 2.
PAGE 29
OB328 A--1qxp 04.4.26 4:49 PM Page 29 Mitsubishi Electric ilmalämpöpumput korjaa ja huoltaa pääkaupunkiseudulla: Jäähdytinpalvelu RefGroup Oy Outdoor fan motor does not operate. I Check of outdoor fan motor Check the resistance of fan motor. (Refer to page 25.) Is the resistance of fan motor normal? No Replace the outdoor fan motor. Yes Disconnect the connector CN771 on the power P.C. board. Disconnect the connector (CN61) between compressor and power transistor module.
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OB328 A--1qxp 04.4.26 4:49 PM Page 30 Mitsubishi Electric ilmalämpöpumput korjaa ja huoltaa pääkaupunkiseudulla: Jäähdytinpalvelu RefGroup Oy Outdoor unit does not operate at all or stops immediately due to over current. K Check of current-limiting resistor When the current-limiting resistor is open, the rush current limiting relay (X64) may not work properly. Start Does current-limiting resistor (R64) detect 10"? No ∞ Replace the power P.C. board.
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OB328A --2qxp 04.4.26 4:50 PM Page 31 Mitsubishi Electric ilmalämpöpumput korjaa ja huoltaa pääkaupunkiseudulla: Jäähdytinpalvelu RefGroup Oy When OPERATION INDICATOR lamp flashes ON and OFF in every 0.5-second. Outdoor unit doesn’t operate. N How to check mis-wiring and serial signal error (when outdoor unit does not work) Start • Turn ON the power supply. • Press once EMERGENCY OPERATION switch. w Short circuit of JPG and JPS on the indoor electronic control P.C.
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OB328A --2qxp 04.4.26 4:50 PM Page 32 Mitsubishi Electric ilmalämpöpumput korjaa ja huoltaa pääkaupunkiseudulla: Jäähdytinpalvelu RefGroup Oy MUZ-A09YV - E1 MUZ-A12YV - E1 MUZ-A09YVH - E1 MUZ-A12YVH - E1 Inverter P.C. board (Refer to page 29.) Back side of unit LD66A LD61A 280V ~ 370V DC 230V AC Jumper wire for change in defrost setting (JS) (Refer to page 22.) LED monitor lamp Front side of unit Connecting wire with power P.C.
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OB328A --2qxp 04.4.26 4:50 PM Page 33 Mitsubishi Electric ilmalämpöpumput korjaa ja huoltaa pääkaupunkiseudulla: Jäähdytinpalvelu RefGroup Oy MUZ-A09YV - E1 MUZ-A09YVH - E1 Power P.C. board MUZ-A12YV - E1 MUZ-A12YVH - E1 Connecting wire with inverter P.C. board (CN726) (Refer to page 30.) Back side of unit R.V. coil (CN721) Front side of unit 230V AC Output to drive outdoor fan motor (CN771) 230V AC 230V AC Heater connector 230V AC (CN722) } MUZ-A09YVH MUZ-A12YVH 33 www.ilmalämpöpumput.
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OB328A --2qxp 04.4.26 4:50 PM Page 34 Mitsubishi Electric ilmalämpöpumput korjaa ja huoltaa pääkaupunkiseudulla: Jäähdytinpalvelu RefGroup Oy 12 DISASSEMBLY INSTRUCTIONS <"Terminal with lock mechanism" Detaching points> In case of terminal with lock mechanism, detach the terminal as shown below. There are two types ( Refer to (1) and (2)) of the terminal with lock mechanism. The terminal with no lock mechanism can be removed by pulling it out. Check the shape of the terminal and work.
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OB328A --2qxp 04.4.26 4:50 PM Page 35 Mitsubishi Electric ilmalämpöpumput korjaa ja huoltaa pääkaupunkiseudulla: Jäähdytinpalvelu RefGroup Oy OPERATING PROCEDURE PHOTOS 2. Removing the inverter assembly, inverter P.C. board and power P.C. board (1) Remove the top panel, cabinet and service panel. (Refer to 1.) (2) Disconnect the indoor/outdoor connecting wire and remove the back panel. (Refer to 1.) (3) Disconnect the ground wire, the lead wire to the reactor and the following connectors;
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OB328A --2qxp 04.4.26 4:50 PM Page 36 Mitsubishi Electric ilmalämpöpumput korjaa ja huoltaa pääkaupunkiseudulla: Jäähdytinpalvelu RefGroup Oy OPERATING PROCEDURE PHOTOS 4. Removing the defrost thermistor and discharge temperature thermistor Photo 5 R.V. coil (1) Remove the top panel, cabinet and service panel. (Refer to 1.) (2) Disconnect the indoor/outdoor connecting wire and remove the back panel. (Refer to 1.) (3) Remove the inverter assembly. (Refer to 2.
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OB328A --2qxp 04.4.26 4:50 PM Page 37 Mitsubishi Electric ilmalämpöpumput korjaa ja huoltaa pääkaupunkiseudulla: Jäähdytinpalvelu RefGroup Oy OPERATING PROCEDURE PHOTOS 5. Removing outdoor fan motor (1) Remove the top panel, cabinet and service panel. (Refer to 1.) (2) Disconnect the indoor/outdoor connecting wire and remove the back panel. (Refer to 1.) (3) Remove the inverter assembly. (Refer to 2.) (4) Remove the propeller. (5) Remove the screws fixing the fan motor.
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OB328A --2qxp 04.4.26 4:50 PM Page 38 Mitsubishi Electric ilmalämpöpumput korjaa ja huoltaa pääkaupunkiseudulla: Jäähdytinpalvelu RefGroup Oy 13 PARTS LIST MUZ-A09YV - E1 MUZ-A12YV - E1 E1 MUZ-A09YVH MUZ-A12YVH - E1 13-1. OUTDOOR UNIT STRUCTURAL PARTS AND FUNCTIONAL PARTS 10 9 16 15 14 17 20 18 19 21 13 1 11 12 3 2 4 5 6 8 7 Part number that is circled is not shown in the illustration. No. Part No.
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OB328A --2qxp 04.4.26 4:50 PM Page 39 Mitsubishi Electric ilmalämpöpumput korjaa ja huoltaa pääkaupunkiseudulla: Jäähdytinpalvelu RefGroup Oy MUZ-A09YV - E1 MUZ-A09YVH - E1 MUZ-A12YV - E1 MUZ-A12YVH - E1 13-2. OUTDOOR UNIT ELECTRICAL PARTS 9 8 7 6 2 3 1 4 5 No. Part No.
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OB328A --2qxp 04.4.26 4:50 PM Page 40 Mitsubishi Electric ilmalämpöpumput korjaa ja huoltaa pääkaupunkiseudulla: Jäähdytinpalvelu RefGroup Oy MUZ-A09YV - E1 MUZ-A12YV - E1 13-3. DRAIN SOCKET Outdoor unit {42 drain hole 1 Soft vinyl chloride hose of 25mm inside diameter. No. Parts No. Parts Name Q'ty/unit Symbol in Wiring MUZ-A09YV- E1 MUZ-A12YVDiagram 1 E02 838 704 DRAIN SOCKET 1 E1 Remarks 1 HEAD OFFICE: MITSUBISHI DENKI BLDG.