Mitsubishi MU-GA50VB-E1, MU-GA60VB-E1, MU-GA80VB-E1 Service Manual

SPLIT-TYPE, AIR CONDITIONERS

HFC

utilized

R410A

OUTDOOR UNIT

SERVICE MANUAL

Wireless type
Models

Revision:A

• RoHS PARTS LIST has been added.
Please void OB370.

No. OB370

REVISED EDITION-A

MU-GA50VB ­MU-GA60VB ­MU-GA80VB -

MU-GA50VB
MU-GA60VB

E1

E1

E1

Indoor unit service manual
MS-GA•VB Series (OB369)

CONTENTS

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

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

3. SPECIFICATION·················································6

4. NOISE CRITERIA CURVES·······························8

5. OUTLINES AND DIMENSIONS·························9

6. WIRING DIAGRAM ··········································10

7. REFRIGERANT SYSTEM DIAGRAM··············12

8. PERFORMANCE CURVES······························15

9. TROUBLESHOOTING······································23

10. DISASSEMBLY INSTRUCTIONS·····················30

11. PARTS LIST······················································36

12. RoHS PARTS LIST···········································40

NOTE:

This service manual describes technical data of outdoor units.
RoHS compliant products have <G> mark on the spec name plate.
For servicing of RoHS compliant products, refer to the RoHS Parts List.

Refrigerating

oil

Refrigerant

New refrigerant

R410A

HFC-32: HFC-125 (50%:50%)

Pseudo-azeotropic refrigerant

Not included

A1/A1

72.6

-51.4

1.557
64

Non combustible

0

1730

From liquid phase in cylinder

Possible

Incompatible oil

Non
Non

Previous refrigerant

R22

R22 (100%)

Single refrigerant

Included

A1

86.5

-40.8

0.94

44.4

Non combustible

0.055
1700

Gas phase

Possible

Compatible oil

Light yellow

Non

Refrigerant
Composition (Ratio)
Refrigerant handling
Chlorine
Safety group (ASHRAE)
Molecular weight
Boiling point (:)
Steam pressure [25:](Mpa)
Saturated steam density [25:](Kg/K)
Combustibility
ODP w1
GWP w2
Refrigerant charge method
Additional charge on leakage
Kind
Color
Smell

w1:Ozone Depletion Potential : based on CFC-11
w2 :Global Warming Potential : based on CO

2

Revision:A

• RoHS PARTS LIST has been added.

1

MU-A18WV - ➔MU-GA50VB -

1. Oil separator has been removed.

2. Model name has been changed.
Indication of capacity has been changed. (BTU➔kW)

MU-A24WV - ➔MU-GA60VB ­MU-A30WV - ➔MU-GA80VB -

1. Model name has been changed.
Indication of capacity has been changed. (BTU➔kW)

TECHNICAL CHANGES

E1E1

E1E1

E1E1

INFORMATION FOR THE AIR CONDITIONER WITH R410A REFRIGERANT

• This room air conditioner adopts an HFC refrigerant (R410A) which never destroys the ozone layer.

• Pay particular attention to the following points, though the basic installation procedure is same as that for R22 conditioners.
1 As R410A has working pressure approximate 1.6 times as high as that of R22, some special tools and piping parts/

materials are required. Refer to the table below.

2 Take sufficient care not to allow water and other contaminations to enter the R410Arefrigerant during storage and

installation, since it is more susceptible to contaminations than R22.

3 For refrigerant piping, use clean, pressure-proof parts/materials specifically designed for R410A. (Refer to 2. Refrigerant

piping.)

4 Composition change may occur in R410A since it is a mixed refrigerant. When charging, charge liquid refrigerant to prevent

composition change.

2

NOTE : The unit of pressure has been changed to MPa on the international system of units(SI unit system).

New Specification Current Specification

The incompatible refrigerating oil easily separates from
refrigerant and is in the upper layer inside the suction muffler.
Raising position of the oil back hole enables to back the
refrigerating oil of the upper layer to flow back to the
compressor.

Since refrigerant and refrigerating oil are compatible each,
refrigerating oil backs to the compressor through the lower
position oil back hole.

Compressor

Suction muffler

Oil back hole

Refrigerating oil

Refrigerant

Compressor

Suction muffler

Oil back hole

Refrigerating oil /Refrigerant

Compressor

-30 -20 -10 0 10 20

30

40 50 60

-0.5

0.0

0.5

1.0

1.5

2.0

2.5

3.0

3.5

4.0

(MPa [Gauge])

R410A
R22

Conversion chart of refrigerant temperature and pressure

Saturated liquid pressure

(:)

R410A tools

Can R22 tools be used?

Gas leak detector

R410A has high pressures beyond the measurement range of existing
gauges. Port diameters have been changed to prevent any other refrigerant
from being charged into the unit.

Hose material and cap size have been changed to improve the pressure
resistance.

Dedicated for HFC refrigerant.

6.35 mm and 9.52 mm

Description

Clamp bar hole has been enlarged to reinforce the spring strength in the tool.
Provided for flaring work (to be used with R22 flare tool).

Provided to prevent the back flow of oil. This adapter enables you to use
vacuum pumps.

It is difficult to measure R410A with a charging cylinder because the
refrigerant bubbles due to high pressure and high-speed vaporization

No

No

No

Yes

Yes

New

New

New

Gauge manifold

Charge hose

Torque wrench

Flare tool
Flare gauge

Vacuum pump
adapter

Electronic scale for
refrigerant charging

No : Not Substitutable for R410A Yes : Substitutable for R410A

No 12.7 mm and 15.88 mm

The conversion factor is: 1(MPa [Gauge]) =10.2(kgf/ff[Gauge])

NOTE : The unit of pressure has been changed to MPa on the

international system of units(SI unit system).

The conversion factor is: 1(MPa [Gauge]) =10.2(kgf/ff[Gauge])

1.Tools dedicated for the air conditioner with R410A refrigerant

The following tools are required for R410A refrigerant. Some R22 tools can be substituted for R410A tools.
The diameter of the service port on the stop valve in outdoor unit has been changed to prevent any other refrigerant being
charged into the unit. Cap size has been changed from 7/16 UNF with 20 threads to 1/2 UNF with 20 threads.

3

Electronic scale for refrigerant charging

Outdoor unit

Refrigerant gas
cylinder
operating valve

Refrigerant gas cylinder
for R410A with siphon

Refrigerant (liquid)

Service port

Gauge manifold
valve (for R410A)

Union

Liquid pipe
Gas pipe

Stop valve

Indoor unit

Charge hose (for R410A)

R410A

Pipe diameter

mm

6.35

9.52

12.7

15.88

17
22
26
29

Dimension of flare nut

R22

17
22
24
27

2.Refrigerant piping

Wall
thickness

Outside diameter

Pipe

mm

For liquid

For gas

6.35

9.52

12.7

15.88

0.8 mm

0.8 mm

0.8 mm

1.0 mm

Heat resisting foam plastic
Specific gravity 0.045 Thickness 8 mm

Insulation material

1 Specifications

Use the refrigerant pipes that meet the following specifications.

• Use a copper pipe or a copper-alloy seamless pipe with a thickness of 0.8 mm (6.35, 9.52, 12.7), 1.0 mm (15.88).
Never use any pipe with a thickness less than 0.8 mm (6.35, 9.52, 12.7), 1.0 mm (15.88), as the pressure resistance is
insufficient.

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”.

3.Refrigerant oil

Apply the special refrigeration oil (accessories: packed with indoor unit) to the flare and the union seat surfaces.

4.Air purge

• Do not discharge the refrigerant into the atmosphere.

Take care not to discharge refrigerant into the atmosphere during installation, reinstallation, or repairs to the refrigerant

circuit.

• Use the vacuum pump for air purging for the purpose of environmental protection.

5.Additional charge

For additional charging, charge the refrigerant from liquid phase of the gas cylinder.
If the refrigerant is charged from the gas phase, composition change may occur in the refrigerant inside the cylinder and the
outdoor unit. In this case, ability of the refrigerating cycle decreases or normal operation can be impossible. However,
charging the liquid refrigerant all at once may cause the compressor to be locked. Thus, charge the refrigerant slowly.

4

2

Drainage hose

Piping

Air inlet

Air inlet

Air outlet

Drain outlet

(back and side)

Air outlet

(back and side)

PART NAMES AND FUNCTIONS

MU-GA50VB
MU-GA60VB

MU-GA80VB

5

3

Outdoor model

Function

Power supply

Capacity
Dehumidification
Air flow(High)
Power outlet
Running current
Power input
Power factor
Starting current
Compressor motor current
Fan motor current

Model
Output
Winding
resistance(at 20:)
Model
Winding
resistance(at 20:)
Dimensions WOHOD
Weight
Sound level(High)
Fan speed(High)
Fan speed regulator
Refrigerant filling
capacity(R410A)
Refrigerating oil (Model)

kW

r/h

K /h

A

A
W
%

A

A

A

W

"

"

mm

kg

dB

rpm

kg
cc

MU-GA50VB

Cooling

Single phase

230V, 50Hz

5.0

2.5

2,196

15

7.90

1,750

96
37

7.51

0.39

2.76

RN196VHSHT

1,300
C-R 1.80
C-S 3.00

RA6V50-PA
WHT-BLK 79.5
BLK-RED 83.0

850o605o290

44
52

828

1

1.45

520 (NEO22)

MU-GA60VB

Cooling

Single phase

230V, 50Hz

6.5

3.4

2,322

25

10.82
2,420

97
74

10.27

0.55

2.62

NN29VBAHT

1,900
C-R 0.80
C-S 1.64

RA6V60-MA
WHT-BLK 71
BLK-RED 89

850o605o290

60
53

873

1

2.00

1,200 (NEO22)

Electrical

data

Compressor

Fan

motor

Special

remarks

Coefficient of performance(C.O.P)

Capacity

SPECIFICATION

NOTE: Test conditions are based on ISO 5151.

Cooling : Indoor DB27°C WB19°C

Outdoor DB35°C WB(24°C)

Indoor-Outdoor piping length : 5m

6

Outdoor model

Function

Power supply

Capacity
Dehumidification
Air flow(High/Low )

Capacity

Power outlet
Running current
Power input
Power factor

Electrical

data

Starting current
Compressor motor current
Fan motor current

w

kW

R/h

K /h

A

A
W
%

A

A

A

Coefficient of performance(C.O.P)

Model
Output
Winding
resistance(at 20:)

Compressor

W

"

Model
Winding

Fan

motor

resistance(at 20:)
Dimensions WOHOD
Weight
Sound level(High/Low )
Fan speed(High/Low )

w

"

mm

kg

w

dB

rpm
Fan speed regulator
Refrigerant filling
capacity(R410A)

Special

remarks

Refrigerating oil (Model)
Thermistor RT62(at 25:)
Thermistor RT63(at 0:)

kg

cc
k"
k"

NOTE: Test conditions are based on ISO 5151.

Cooling : Indoor DB27°C WB19°C

Outdoor DB35°C WB(24°C)

Indoor-Outdoor piping length : 5m

w Reference value

MU-GA80VB

Cooling

Single phase

230V, 50Hz

8.5

4.6

2,940/1,470

w

25

14.42
3,191

96
90

13.85

0.57

2.61

NN37VAAHT

2,500
C-R 0.64
C-S 1.63

RA6V75-AD

WHT-BLK 62.8 BLK-YLW 55.9

YLW-RED 26.0

840o850o330

75

w

55/53

805/435

w

2

2.40

1,300 (NEO 22)

231.44

33.18

7

4

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

BAND CENTER FREQUENCIES, Hz

Test conditions,
Cooling : Dry-bulb temperature 35: Wet-bulb temperature 24:

APPROXIMATE
THRESHOLD OF
HEARING FOR
CONTINUOUS
NOISE

52

SPL(dB(A)) LINE

High

FAN SPEED

OCTAVE BAND SOUND PRESSURE LEVEL, dB re 0.0002 MICRO BAR

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

BAND CENTER FREQUENCIES, Hz

Test conditions,
Cooling : Dry-bulb temperature 35: Wet-bulb temperature 24:

APPROXIMATE
THRESHOLD OF
HEARING FOR
CONTINUOUS
NOISE

55

SPL(dB(A)) LINE

High

FAN SPEED

OCTAVE BAND SOUND PRESSURE LEVEL, dB re 0.0002 MICRO BAR

OUTDOOR UNIT

MICROPHONE

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

APPROXIMATE
THRESHOLD OF
HEARING FOR
CONTINUOUS
NOISE

Test conditions,
Cooling : Dry-bulb temperature 35: Wet-bulb temperature 24:

53

SPL(dB(A)) LINE

High

FAN SPEED

NOISE CRITERIA CURVES

MU-GA50VB

MU-GA60VB

MU-GA80VB

8

5

100mm or more

1

0

0m

m

o

r m

ore

100mm or more

350mm or more

5

0

0

m

m

o

r m

o

re

Drainage
3holes [33

Air out

Air in

Air in

Service panel

Liquid refrigerant
pipe joint

Refregerant pipe
(flared) [6.35

Gas refregerant
pipe joint

Refregerant pipe
(flared) [12.7 (MU-GA50VB)
[15.88 (MU-GA60VB)

35-

30

-

30

100

161

157

74

850

500

183

20

292

605

248

35

350

50

290

310

345

20

355

90

Drainage
hole [16.2

30

-

35-

155

90

198

40

515

299

66

34

51

330

360

850

430

500

80

121

840

Open as a rule
500mm or more if
the front and both
sides are open

100mm or more
200mm or more if
there are obstacles
to both sides

Open as a rule
500mm or more if the back,
both sides and top are open

350mm or more

100mm or more

Service panel

Gas refrigerant
pipe joint
Refrigerant pipe
(flared) [15.88

Liquid refrigerant
pipe joint
Refrigerant pipe
(flared) [9.52

OUTLINES AND DIMENSIONS

MU-GA50VB MU-GA60VB

Unit: mm

MU-GA80VB

9

6

BRN

WHT
WHT

POWER SUPPLY
230V 50Hz

~/N

TB1

CIRCUIT BREAKER

PE

BLU

N

GRN/YLW

BRN

L

NO COM

52C

TB2

CONNECTING
12V

INDOOR UNIT

TO

BLK

1

WHT

2

52C

C2

4

WHT

ORN

RED

2
3

1

RED

C1

BLK

BLK

ORN
WHT

RED

MF

R

MC

S

C

DSAR

BLU

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.
: Connector

: Terminal block

NOTES:

SYMBOL

C1
C2

DSAR

NAME
COMPRESSOR CAPACITOR
OUTDOOR FAN CAPACITOR
SURGE ABSORBER

SYMBOL

MC
MF

TB1,TB2

NAME
COMPRESSOR (INNER PROTECTOR)
OUTDOOR FAN MOTOR (INNER PROTECTOR)
TERMINAL BLOCK

SYMBOL

52C

NAME

COMPRESSOR CONTACTOR

TB1

RED

MC

~/N
230V 50Hz

POWER SUPPLY

52C

GRN/YLW

PE

N

CIRCUIT BREAKER

X1

NO

L

NO

REDRED

WHT

BLU

ORN

C2

WHT

3

4

BLK

1
2

ORN

COM

BLU

COM

52C

BLK

S

MF

R

C

12V

INDOOR UNIT
CONNECTING

TO

X1

1

BLK

BRN

WHT

2

TB2

DSAR

WHT

C1

BLU

BRN

WHT

BRN

BRN

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.
: Connector

: Terminal block

NOTES:

SYMBOL

C1
C2

DSAR

NAME
COMPRESSOR CAPACITOR
OUTDOOR FAN CAPACITOR
SURGE ABSORBER

SYMBOL

MC
MF

TB1,TB2

NAME
COMPRESSOR (INNER PROTECTOR)
OUTDOOR FAN MOTOR (INNER PROTECTOR)
TERMINAL BLOCK

SYMBOL

X1

52C

NAME
RELAY
COMPRESSOR CONTACTOR

WIRING DIAGRAM

MU-GA50VB

MU-GA60VB

10

MU-GA80VB

CIRCUIT BREAKER

TB1

L
N

3

PE

GRN/YLW

TB2

~ / N 230V 50Hz

POWER SUPPLY

N

12V

TO INDOOR UNIT CONNECTING

BRN

DSAR

BLU

BRN

BLU

DEICER
P.C. BOARD

BRN

1

52C

WHT

CZ

RT62 RT63

CN662

X52

2

WHT

LEV

6

CN724

T61

A1 A2BLU

SR62
SR61

52C

WHT

MF

YLW

BLK

YLW

BLK

123

NR61

WHT

3456

WHT

C1

ORN

RED

21

CN711

X52

COM

F61

RED

RED

ORN

TAB52

NO

CN730

S

BLK

C2

7
5
3
1

MC

C

R

BLU

RED

BLU

SYMBOL

CZ
C1
C2

DSAR

F61

LEV

NOTE 1. Use copper conductors only (For field wiring).

CZ SURGE ABSORBER
COMPRESSOR CAPACITOR
OUTDOOR FAN CAPACITOR
SURGE ABSORBER
FUSE(3.15A)
EXPANSION VALVE COIL

2. Since the indoor and outdoor unit connecting wires have polarity, connect them according to the numbers (3,N).

3. Symbols below indicate.

/: Terminal block, : Connector

NAME

SYMBOL

MC

MF

NR61

RT62
RT63

SR61

NAME NAME
COMPRESSOR (INNER PROTECTOR)
OUTDOOR FAN MOTOR (INNER PROTECTOR)
VARISTOR
DISCHARGE TEMPERATURE THERMIST OR
AMBIENT TEMPERA TURE THERMIST OR
SOLID STATE RELAY

SYMBOL

SR62

TB1
TB2
T61
X52
52C

SOLID STATE RELAY
TERMINAL BLOCK
TERMINAL BLOCK
TRANSFORMER
CONTACTOR
COMPRESSOR CONTACTOR

11

7

REFRIGERANT SYSTEM DIAGRAM

MU-GA50VB

Refrigerant pipe [12.7
(with heat insulator)

Flared connection

Flared connection

Stop valve
(with service
port)

Stop
valve

Muffler

Compressor

Strainer

#100

Unit:mm

Outdoor
heat
exchanger

MU-GA60VB

Refrigerant pipe [6.35
(with heat insulator)

Refrigerant pipe [15.88
(with heat insulator)

Flared connection

Stop valve
(with service port)

Muffler

Capillary tube

[3.0o[1.6o600

Muffler

#100

Outdoor
heat
exchanger

Compressor

Flared connection

Refrigerant pipe [6.35
(with heat insulator)

Stop valve

Capillary tube
[3.0X[1.8X500

Refrigerant flow in cooling

12

MU-GA80VB

Indoor
unit

wMax. Height

difference:
10m(MS-GA50/GA60VB)/
15m(MS-GA80VB)

A

Refrigerant Piping
Max. Length

w Height difference should be within 10m(MS-GA50/GA60VB)/
15m(MS-GA80VB) regardless of which unit, indoor or outdoor position is high.

Outdoor unit

Outdoor
heat
exchanger

Flared connection

Discharge
temperature
thermistor
RT62

Flared connection

Stop valve

Stop valve
(with service port)

Capillary tube
[3.6✕[2.4✕50

Refrigerant flow in cooling

Compressor

Refrigerant pipe [15.88
(with heat insulator)

Refrigerant pipe [9.52
(with heat insulator)

LEV

Muffler

Muffler

Strainer

Ambient
temperature
thermistor
RT63

Capillary tube
[4.0✕[2.4✕200
(Upper path)

Capillary tube
[4.0✕[2.4✕100
(Lower path)

Model

Piping size O.D : mm

Refrigerant piping

Max. length : m

A

25

30

Gas

12.7

15.88

Liquid

6.35

9.52

MU-GA50VB

MU-GA60VB
MU-GA80VB

Unit:mm

MAX. REFRIGERANT PIPING LENGTH

MAX. HEIGHT DIFFERENCE

13

Model

MU-GA50VB

Refrigerant piping length (one way)

Outdoor unit precharged

1,450

15m
160

20m

260

25m

360

7m

0

10m

60

ADDITIONAL REFRIGERANT CHARGE(R410A : g)

Model

MU-GA60VB

Refrigerant piping length (one way)

Outdoor unit precharged

2,000

15m
160

20m

260

25m

360

7m

0

10m

60

Outdoor unit

precharged

2,400

0 165 440 715 990 1,165

Refrigerant piping length (one way)

15m10m7m

20m

25m 30m

Model

MU-GA80VB

Calculation : Xg=20g/m ✕ (Refrigerant piping length (m)–7)

Calculation : Xg=20g/m ✕ (Refrigerant piping length (m)–7)

Calculation : Xg=55g/mo(Refrigerant piping length(m)-7)

14