background image

CONTENTS

1. TECHNICAL CHANGES ······························3

2. PART NAMES AND FUNCTIONS ··················4

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

4. NOISE CRITERIA CURVES ··························6

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

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

7. REFRIGERANT SYSTEM DIAGRAM ··········· 10

8. SERVICE FUNCTIONS ······························ 11

9. MICROPROCESSOR CONTROL ················ 13

10. TROUBLESHOOTING ······························· 17

11. DISASSEMBLY INSTRUCTIONS ················· 30

Outdoor unit service manual
MUZ-DM·VA Series (OBH781)
MXZ-DM

VA Series (OBH739)

MSZ-DM50VA

INDOOR UNIT

Models

MSZ-DM50VA

    

-

 

ER1

MSZ-DM60VA

    

-

 

ER1

MSZ-DM71VA

    

-

 

ER1

SERVICE MANUAL

NOTE:

 

RoHS compliant products have 
<G> mark on the spec name plate.

No. OBH780

PARTS CATALOG (OBB780)

Summary of Contents for MSZ-DM50VA

Page 1: ...IAGRAM 10 8 SERVICE FUNCTIONS 11 9 MICROPROCESSOR CONTROL 13 10 TROUBLESHOOTING 17 11 DISASSEMBLY INSTRUCTIONS 30 Outdoor unit service manual MUZ DM VA Series OBH781 MXZ DM VA Series OBH739 MSZ DM50VA INDOOR UNIT Models MSZ DM50VA ER1 MSZ DM60VA ER1 MSZ DM71VA ER1 SERVICE MANUAL NOTE RoHS compliant products have G mark on the spec name plate No OBH780 PARTS CATALOG OBB780 ...

Page 2: ...h the refrigerant Do not touch the hot or cold areas in the refrigeration cycle When the repair or the inspection of the circuit needs to be done without turning off the power exercise great caution not to touch the live parts Use the specified 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 o...

Page 3: ...3 1 TECHNICAL CHANGES MSZ DM50VA ER1 MSZ DM60VA ER1 MSZ DM71VA ER1 1 New model OBH780 ...

Page 4: ...ng section Horizontal vane Air inlet Air lter Front panel Air outlet Heat exchanger Emergency operation switch Remote controller Air cleaning lter Silver ionized air purifier filter option Display section Operation indicator lamp Remote control receiving section Horizontal vane Air inlet Air lter Front panel Air outlet Heat exchanger Emergency operation switch Air cleaning lter Silver ionized air ...

Page 5: ...192 High 667 957 981 Med 497 752 763 Low 364 565 619 Sound level Cooling Super High dB A 43 50 High 40 44 Med 36 38 Low 28 31 33 Heating Super High dB A 47 49 High 41 44 Med 34 38 Low 27 31 33 Fan speed Cooling Super High rpm 1 120 1 250 High 1 000 Med 860 850 Low 660 690 730 Heating Super High rpm 1 220 1 250 High 1 000 1 050 1 070 Med 800 870 880 Low 640 700 750 Fan speed regulator 4 Remote cont...

Page 6: ...g Dry bulb temperature 20 C 4 NOISE CRITERIA CURVES MSZ DM50VA 90 80 70 60 50 40 30 20 10 63 125 250 500 1000 2000 4000 8000 NC 60 NC 50 NC 40 NC 30 NC 20 NC 70 OCTAVE BAND SOUND PRESSURE LEVEL dB re 0 0002 MICRO BAR BAND CENTER FREQUENCIES Hz COOLING FUNCTION SPL dB A LINE Super High FAN SPEED HEATING 45 47 NC 10 OBH780 ...

Page 7: ... 50 NC 40 NC 30 NC 20 NC 70 OCTAVE BAND SOUND PRESSURE LEVEL dB re 0 0002 MICRO BAR BAND CENTER FREQUENCIES Hz COOLING FUNCTION SPL dB A LINE Super High FAN SPEED HEATING 50 49 NC 10 90 80 70 60 50 40 30 20 10 63 125 250 500 1000 2000 4000 8000 NC 60 NC 50 NC 40 NC 30 NC 20 NC 70 OCTAVE BAND SOUND PRESSURE LEVEL dB re 0 0002 MICRO BAR BAND CENTER FREQUENCIES Hz COOLING FUNCTION SPL dB A LINE Super...

Page 8: ... 132 56 18 Piping Insulation Ø37 O D Liquid line Ø7 0 0 39m Flared connection Ø6 35 Gas line Ø9 52 0 34m Flared connection Ø12 7 Drain hose Insulation Ø28 Connected part Ø16 O D MSZ DM60VA MSZ DM71VA Piping Insulation Ø50 O D Liquid line Ø8 0 39m Flared connection Ø6 35 Gas line Ø12 0 34m Flared connection Ø15 88 Drain hose Insulation Connected part Ø16 O D MSZ DM60VA MSZ DM71VA Piping Insulation ...

Page 9: ...9 6 WIRING DIAGRAM MSZ DM60VA MSZ DM71VA MSZ DM50VA OBH780 ...

Page 10: ...efrigerant pipe ø6 35 with heat insulator Indoor coil thermistor RT12 Indoor coil thermistor RT13 MSZ DM60VA MSZ DM71VA Indoor heat exchanger Flared connection Room temperature thermistor RT11 Flared connection Refrigerant flow in cooling Refrigerant flow in heating Refrigerant pipe ø15 88 with heat insulator Refrigerant pipe ø6 35 MSZ DM60VA ø9 52 MSZ DM71VA with heat insulator Indoor coil thermi...

Page 11: ...3 unit Solder J2 Same as at left No 4 unit Cut J1 and solder J2 How to set the remote controller exclusively for particular indoor unit After you turn the breaker ON the first remote controller that sends the signal to the indoor unit will be regarded as the remote controller for the indoor unit The indoor unit will only accept the signal from the remote controller that has been assigned to the in...

Page 12: ...Therefore the special countermeasures are required to prevent the main voltage drop or the rush of the starting current by adding to the system that allows the units to start one by one JR77 Indoor electronic control P C board CN10A CN111 CN151 CN112 CN110 8 3 AUTO RESTART FUNCTION When the indoor unit is controlled with the remote controller the operation mode the set temperature and the fan spee...

Page 13: ...out 2 C or more away from set temperature The room temperature is approaching the set tem perature About 1 to 2 C from set temperature Standby mode Only during multi system operation Lit Blinking Not lit 9 MICROPROCESSOR CONTROL 9 1 COOL OPERATION 1 Press STOP OPERATE OFF ON button OPERATION INDICATOR lamp of the indoor unit turns on with a beep tone 2 Select COOL mode with OPERATION SELECT button...

Page 14: ...rol This mode continues until the temperature of indoor heat exchanger falls 3 Defrosting Defrosting starts when the temperature of outdoor heat exchanger becomes too low The compressor stops once the indoor outdoor fans stop the 4 way valve reverses and the compressor re starts This mode continues until the temperature of outdoor heat exchanger rises or the fixed time passes 3 Positioning To conf...

Page 15: ...OL mode set temperature is automatically set 2 C higher Also the horizontal vane swings in various cycle SWING operation makes you feel cooler than set temperature So even though the set temperature is higher the air conditioner can keep comfort As a result energy can be saved ECONO COOL operation is cancelled when ECONO COOL button is pressed once again or VANE CONTROL button is pressed or change...

Page 16: ...he fan speed shifts to Med The coil frost prevention works even in the test run or the emergency operation In the test run or emergency operation the horizontal vane operates in VANE AUTO mode Emergency operation continues until EMERGENCY OPERATION switch is pressed once or twice or the unit receives any signal from the remote controller In the latter case normal operation will start NOTE Do not p...

Page 17: ...laced This function is equipped to prevent the microcomputer from malfunctioning due to the voltage drop caused by the battery replacement 3 Do not use the leaking batteries Press RESET button with a thin instrument and then use the remote controller Remove the back lid and insert batteries Then reattach the back lid 10 1 CAUTIONS ON TROUBLESHOOTING 1 Before troubleshooting check the following 1 C...

Page 18: ...nking pattern and identify the abnormal point by referring to the table of indoor unit failure mode recall function Refer to 10 2 2 Make sure to check at least 2 consecutive blinking cycles 2 Releasing the failure mode recall function Release the failure mode recall function by the following procedures Turn OFF the power supply and turn it ON again Press RESET button of the remote controller The o...

Page 19: ...cs of the main indoor coil ther mistor the sub indoor coil thermistor 10 7 3 time flash 2 5 second OFF Serial signal The serial signal from outdoor unit is not re ceived for a maximum of 6 minutes Refer to 10 6 How to check miswiring and serial signal error 11 time flash 2 5 second OFF Indoor fan motor The rotational frequency feedback signal is not emitted for the 12 seconds after the indoor fan ...

Page 20: ... operation means the operation within 30 minutes after EMERGENCY OPERA TION switch is pressed Refer to outdoor unit service manual Upper lamp Flash on and off at 0 5 sec ond intervals Cause Indoor Outdoor unit Miswiring or trouble of serial signal Upper lamp 2 time flash Cause Indoor unit Trouble of room temperature indoor coil thermistor Upper lamp 3 time flash Cause Indoor unit Trouble of indoor...

Page 21: ... electronic control P C board 5 Outdoor power sys tem Upper lamp flashes 5 time flash 2 5 second OFF It consecutively occurs 3 times that the com pressor stops for overcurrent protection or start up failure protection within 1 minute after start up Refer to How to check of in verter compressor Refer to outdoor unit service manual Check the stop valve 6 Outdoor thermistors Upper lamp flashes 6 time...

Page 22: ...erminals with a tester Part temperature 10 30 C Color of the lead wire Normal RED BLK 235 255 Ω BLK BLK RED BLK BLK ROTOR OPERATION INDICATOR No Abnormal point Operation indicator lamp Symptom Condition Remedy 1 MXZ type Operation mode setting Upper lamp lights and lower lamp flashes 2 5 second OFF Outdoor unit operates but indoor unit does not operate The operation mode of the each indoor unit is...

Page 23: ...pressed the voltage measured at 2 above goes 0 V DC although the indoor P C board is normal Does the voltage between CN211 and on the power P C board rise to the range of 3 to 6 V DC within 12 seconds after EMERGENCY OPERATION switch is pressed Replace the indoor fan motor Yes No The indoor fan motor error has occurred and the indoor fan repeats 12 second ON and 30 second OFF 3 times and then stop...

Page 24: ...tart type within the range of 1 m 2 Yes No Reinstall the unit away from lights Attach a filter on receiving part Replace the indoor electronic control P C board Including the receiver 1 Look at the image of the signal transmitting section of the remote controller through the monitor of a digital camera or a camera phone It is normal if the LED of the signal transmitting section lights up when the ...

Page 25: ...eplace the indoor electronic control P C board Measure the resistance of the vane motor coil Refer to 10 5 Short circuit Replace the vane motor and the indoor electronic control P C board 1 The fan motor connector s lead wire is red whereas is black 2 Connect of the tester to fan motor connector s lead wire and to lead wire otherwise the resistance cannot be measured properly 3 Please replace the ...

Page 26: ...verter P C board in the outdoor unit repeat 3 6 second OFF and 0 8 second ON quick blinking for 3 minutes after the outdoor unit is energized Check the blinking pattern within 3 minutes after LED is turned on Af ter 3 minutes LED will blink 6 times whether the inverter P C board in the outdoor unit is normal or not No Replace the inverter P C board in the outdoor unit 2 Yes A 2 Be careful of 140 V...

Page 27: ...he installation condition combination of specific conditions such as antennas or wiring Check the following before asking for service 1 Devices affected by the electromagnetic noise TV sets radios FM AM broadcast shortwave 2 Channel frequency broadcast station affected by the electromagnetic noise 3 Channel frequency broadcast station unaffected by the electromagnetic noise 4 Layout of indoor outd...

Page 28: ... TAB1 3 6 V DC 15 V DC GND High voltage DC 325 V DC 0 or 15 V DC Indoor terminal block connecting TAB2 Timer short mode point Refer to 8 1 Room temperature thermistor RT11 CN111 Connector to Indoor coil thermistor RT12 RT13 CN112 Vane motor CN151 Connector to indoor power P C board CN10A 12V DC 5V DC To disable Auto restart function cut the Jumper wire to JR77 Refer to 8 3 Emergency operation swit...

Page 29: ...k connecting TAB1 3 6 V DC 15 V DC GND High voltage DC 325 V DC 0 or 15 V DC Indoor terminal block connecting TAB2 Timer short mode point Refer to 8 1 Room temperature thermistor RT11 CN111 Connector to Indoor coil thermistor RT12 RT13 CN112 Vane motor CN151 Connector to indoor power P C board CN10A 12V DC 5V DC To disable Auto restart function cut the Jumper wire to JR77 Refer to 8 3 Emergency op...

Page 30: ...al with this connector has the locking mechanism Slide the sleeve Pull the terminal while pushing the locking lever Hold the sleeve and pull out the terminal slowly Connector Sleeve Locking lever Terminal with locking mechanism Detaching points The terminal which has the locking mechanism can be detached as shown below There are 2 types refer to 1 and 2 of the terminal with locking mechanism The t...

Page 31: ...ctrical cover and remove the electrical cover 8 Disconnect the following connectors Indoor power P C board CN211 Indoor fan motor CN201 TAB1 TAB2 Terminal block CN20A To the indoor electronic control P C board 9 Remove the upper catch of the electrical box and pull out the electrical box To attach the electrical box pass the wires connecting the indoor power P C board and the indoor electronic con...

Page 32: ...the back side of the control P C board holder 5 Unhook the catches of the control P C board holder and open the control P C board holder 6 Remove the indoor electronic control P C board from the control P C board holder 4 Removing the vane motor 1 Remove the panel Refer to 1 Remove the corner box 2 Remove the control P C board holder and the electrical box Refer to 2 3 Pull out the drain hose from...

Page 33: ...ad wire of the fan motor from the motor band 10 Disengage the hooks of the motor band and remove the motor band Pull out the indoor fan motor 11 Remove the indoor coil thermistor from the heat exchanger Install the indoor coil thermistor in its former position when assembling it 12 Remove the screws fixing the left side of the heat exchanger 13 Lift the heat exchanger and pull out the line flow fa...

Page 34: ...ew caps on the panel and remove the screws of the panel 2 Pull the panel slightly toward you and then remove the panel by pushing it upward 11 2 MSZ DM60VA MSZ DM71VA NOTE Turn OFF the power supply before disassembly Photo 1 Screws of the panel Front panel 34 OBH780 ...

Page 35: ...al cover and remove the electrical cover 10 Disconnect the CN211 Indoor fan motor from the indoor power P C board 11 Remove the upper catch of the electrical box and pull out the electrical box To attach the electrical box pass the wires connecting the indoor power P C board and the indoor electronic control P C board through Pass the lead wires of the fan motor through as shown in the Photo 3 12 ...

Page 36: ...ck side of the control P C board holder 5 Unhook the catches of the control P C board holder and open the control P C board holder 6 Remove the indoor electronic control P C board from the control P C board holder 4 Removing the vane motor 1 Remove the panel Refer to 1 Remove the corner box 2 Remove the control P C board holder water cover and the electrical box Refer to 2 3 Pull out the drain hos...

Page 37: ...d remove the motor band Pull out the indoor fan motor 8 Remove the indoor coil thermistor from the heat exchanger Install the indoor coil thermistor in its former position when assembling it 9 Remove the screws fixing the left side and upper right side of the heat exchanger 10 Lift the heat exchanger and pull out the line flow fan to the lower left When attaching the line flow fan screw the line f...

Page 38: ...hen fixing the indoor coil thermistor to the clip shape holder shape part the lead wire should point down 1 Set the indoor coil thermistor in the center of the clip shape part 2 Check the marked mounting position 3 Mount the clip shape part Position and procedure for mounting the clip shape part About the same length Copyright 2017 MITSUBISHI ELECTRIC CORPORATION Published Jul 2017 No OBH780 Made ...

Reviews: