Mitsubishi Electric MSZ-HJ25VA-E1, MSZ-HJ35VA-E1, MSZ-HJ50VA-E1, MSZ-HJ25VA, MSZ-HJ35VA Service Manual

CONTENTS

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

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

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

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

5. OUTLINES AND DIMENSIONS ························ 7

6. WIRING DIAGRAM ············································ 7

7. REFRIGERANT SYSTEM DIAGRAM ··············· 8

8. SERVICE FUNCTIONS ····································· 9

9. MICROPROCESSOR CONTROL ····················11

10. TROUBLESHOOTING ····································· 15

11. DISASSEMBLY INSTRUCTIONS ···················· 27

MSZ-HJ25VA

-

E1

MSZ-HJ35VA

-

E1

MSZ-HJ50VA

-

E1

Outdoor unit service manual

MUZ-HJ·VA Series (OBH648)

SERVICE MANUAL

No. OBH647

REVISED EDITION-A

INDOOR UNIT

PARTS CATALOG (OBB647)

NOTE:

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

SPLIT-TYPE AIR CONDITIONERS

Models

Revision A:

• MSZ-HJ50VA-E1 has been added.
Please void OBH647.

2

<Preparation before the repair service>

Prepare the proper tools.
Prepare the proper protectors.
Provide adequate ventilation.
After stopping the operation of the air conditioner, turn off the power-supply breaker and remove the power plug.
Discharge the capacitor before the work involving the electric parts.

<Precautions during the repair service>

Do not perform the work involving the electric parts with wet hands.
Do not pour water into the electric parts.
Do not touch 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 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.

Revision A:

• MSZ-HJ50VA-E1 has been added.

OBH647A

3

1

TECHNICAL CHANGES

MSZ-HJ25VA -

E1

MSZ-HJ35VA -

E1

MSZ-HJ50VA -

E1

1. New model

OBH647A

4

Operation indicator lamp

Remote control
receiving section

Emergency

operation switch

Horizontal vane

Air inlet

Air filter

Front panel

Air outlet

Heat exchanger

Emergency operation switch

Remote controller

ACCESSORIES

MSZ-HJ25VA MSZ-HJ35VA MSZ-HJ50VA

Installation plate 1
Installation plate fi xing screw 4 × 25 mm 5
Battery (AAA) for remote controller 2
Wireless remote controller 1
Felt tape (Used for left or left-rear piping) 1

2

PART NAMES AND FUNCTIONS

OBH647A

5

3

SPECIFICATION

Indoor model MSZ-HJ25VA MSZ-HJ35VA MSZ-HJ50VA

Power supply Single phase 230 V, 50 Hz

Breaker Capacity A

10

12

Electrical data

Power input 1 (Total)

Cooling

W

730 1,040 2,050

Heating 870 995 1,480

Running current

1

(Total)

Cooling

A

3.7 4.9 9.0

Heating 4.2 4.8 6.6

Power factor

1 (Total)

Cooling

%

85 92 99

Heating 90 90 97

Starting current

1 (Total) A 4.2 4.9 9.0

Fan motor

Model RC0J40-EF
Current 1

Cooling

A

0.19 0.24 0.27

Heating 0.20 0.22 0.34
Dimensions W × H × D mm 799 × 290 × 232
Weight kg 9

Special remarks

Air direction 5

Airfl ow

Cooling

Super High

m3/h

571 654 772
High 438 470 667
Med. 328 341 547
Low 227 227 380

Heating

Super High

m3/h

598 619 861
High 451 451 667
Med. 328 328 497
Low 208 208 364

Sound level

Cooling

Super High

dB(A)

43 45 45
High 37 38 40
Med. 30 31 36
Low 22 22 28

Heating

Super High

dB(A)

43 44 47
High 37 37 41
Med. 30 30 34
Low 23 23 27

Fan speed

Cooling

Super High

rpm

1,080 1,200 1,120
High 880 930 1,000
Med. 710 730 860
Low 550 550 660

Heating

Super High

rpm

1,120 1,150 1,220
High 900 900 1,000
Med. 710 710 800
Low 520 520 640

Fan speed regulator 4

Remote controller model MP13A

NOTE : Test conditions are based on ISO 5151.
Cooling : Indoor Dry-bulb temperature 27°C Wet-bulb temperature 19°C
Outdoor Dry-bulb temperature 35°C
Heating : Indoor Dry-bulb temperature 20°C
Outdoor Dry-bulb temperature 7°C Wet-bulb temperature 6°C

1 Measured under rated operating frequency.

Specifications and rated conditions of main electric parts

Fuse (F11) T3.15AL250V
Horizontal vane motor (MV) 12 VDC
Varistor

(NR11)

S10K320E3K1 (ERZV14D471)

Terminal block (TB) 5P

OBH647A

6

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

43
43

NC-10

MSZ-HJ25VA

INDOOR UNIT

WALL

MICROPHONE

0.8m

1m

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

Test conditions
Cooling : Dry-bulb temperature 27°C Wet-bulb temperature 19°C

Heating : Dry-bulb temperature 20°C

44

45

NC-10

MSZ-HJ35VA

4

NOISE CRITERIA CURVES

MSZ-HJ50VA

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

OBH647A

7

MSZ-HJ25VA MSZ-HJ35VA MSZ-HJ50VA

Unit : mm

MSZ-HJ25VA MSZ-HJ35VA MSZ-HJ50VA

5

OUTLINES AND DIMENSIONS

6

WIRING DIAGRAM

2325

69

41

799
785 7

290

12063049

57
80

42

43

69

57

42

7

103

130

100

(57°)

225 225 80.5

80.5

61.5

59.5340338

41

42

249

248

21.5

3

167

157

207.5

206.5

172

14

140

57 18

46

Air in

Installation plate

Piping

Drain hose

Air out

11×26 Oblong hole

11×20 Oblong hole

Installation plate

Indoor unit

Wall hole

Φ65

In case of left,

left back,or

left under piping

(using spacer),

108.5 or more

7 or more

33.5 or more
40 or more

20 or more

Piping

Insulation Φ35 O.D

Liquid line Φ6.35 - 0.39m (Flared connection Φ6.35)

Gas line Φ9.52 - 0.34m (Flared connection Φ9.52)

Drain hose

InslationΦ28 Connected part Φ16 O.D active length 370

MSZ-HJ25/35VA

MSZ-HJ50VA

Piping

Insulation Φ37 O.D

Liquid line Φ6.35 - 0.39m (Flared connection Φ6.35)

Gas line Φ9.52 - 0.34m (Flared connection Φ12.7)

Drain hose

InslationΦ28 Connected part Φ16 O.D active length 370

OBH647A

8

MSZ-HJ25VA MSZ-HJ35VA

Indoor
heat
exchanger

Flared connection

Room temperature
thermistor
RT11

Flared connection

Refrigerant flow in cooling
Refrigerant flow in heating

Refrigerant pipe ø9.52
(with heat insulator)

Refrigerant pipe ø6.35
(with heat insulator)

Indoor coil
thermistor
RT12

Indoor coil
thermistor
RT13

Unit : mm

MSZ-HJ50VA

Indoor
heat
exchanger

Flared connection

Room temperature
thermistor
RT11

Flared connection

Refrigerant flow in cooling
Refrigerant flow in heating

Refrigerant pipe ø12.7
(with heat insulator)

Refrigerant pipe ø6.35
(with heat insulator)

Indoor coil
thermistor
RT12

Indoor coil
thermistor
RT13

7

REFRIGERANT SYSTEM DIAGRAM

OBH647A

9

8-2. P.C. BOARD MODIFICATION FOR INDIVIDUAL OPERATION

A maximum of 4 indoor units with wireless remote controllers can be used in a room.
In this case, to operate each indoor unit individually by each remote controller, P.C. boards of remote controller must be
modified according to the number of the indoor unit.

8-1. TIMER SHORT MODE

For service, the following set time can be shortened by short circuiting the timer short mode point on the electronic control
P.C. board. (Refer to 10-7.)
Set time : 3-minute → 3-second (It takes 3 minutes for the compressor to start operation. However, the starting time is

shortened by short circuiting the timer short mode point.)

Table 1

1 unit operation 2 units operation 3 units operation 4 units operation
No. 1 unit No modifi cation Same as at left Same as at left Same as at left
No. 2 unit – Solder J1 Same as at left Same as at left
No. 3 unit – – Solder J2 Same as at left
No. 4 unit – – – Solder both J1 and 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 indoor unit once they are
set.
The setting will be cancelled if the breaker has turned OFF, or the power supply has shut down.
Please conduct the above setting once again after the power has restored.

How to modify the remote controller P.C. board

Remove batteries before modification.
The board has a print as shown below :

The P.C. board has the print “J1” and “J2”. Solder “J1” and “J2” according to the number of indoor unit as shown in Table 1.
After modification, press the RESET button.

NOTE : For modification, take out

the batteries and press
the OPERATE/STOP (ON/
OFF) button 2 or 3 times at
first.

After finish modification,

put back the batteries then
press the RESET button.

MSZ-HJ25VA MSZ-HJ35VA MSZ-HJ50VA

J2

J1

8

SERVICE FUNCTIONS

OBH647A

10

NOTE:

• The operation settings are memorized when 10 seconds have passed after the indoor unit was operated with the

remote controller.

• If main power is turned OFF or a power failure occurs while AUTO START/STOP timer is active, the timer setting is

cancelled.

• If the unit has been off with the remote controller before power failure, the auto restart function does not work as the

power button of the remote controller is off.

• To prevent breaker OFF due to the rush of starting current, systematize other home appliance not to turn ON at the

same time.

• When some air conditioners are connected to the same supply system, if they are operated before power failure, the

starting current of all the compressors may flow simultaneously at restart.

Therefore, the special counter measures 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

CN10ACN111

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 speed
are memorized by the indoor electronic control P.C. board. “AUTO RESTART FUNCTION” automatically starts operation
in the same mode just before the shutoff of the main power.

Operation

If the main power has been cut, the operation settings remain.
After the power is restored, the unit restarts automatically according to the memory.

(However, it takes at least 3 minutes

for the compressor to start running.)

How to disable “AUTO RESTART FUNCTION”

Turn off the main power for the unit.
Cut the Jumper wire to JR77 on the indoor electronic control P.C. board. (Refer to 10-7.)

OBH647A