Mitsubishi Electric MUH-GA20VB-E1, MUH-GA20VB-E2, MUH-GA25VB-E2, MUH-GA25VB-E1, MUH-GA35VB-E1 Service Manual

HFC

utilized

R410A

SPLIT-TYPE, HEAT PUMP AIR CONDITIONERS

OUTDOOR UNIT

SERVICE MANUAL

Wireless type
Models

Revision B:

● MUH-GA35VB - has been added.
Please void OB387 REVISED EDITION-A.

E3

No. OB387

REVISED EDITION-B

MUH-GA20VB­MUH-GA20VB­MUH-GA25VB­MUH-GA25VB­MUH-GA35VB­MUH-GA35VB-

MUH-GA20VB
MUH-GA25VB
MUH-GA35VB

E1

E2

E1

E2

E1

E3

Indoor unit service manual

MSC-GA• VB Series (OB385)
MSC-CA• VB Series (OB393)
MSC-CB• VB Series (OB439)

CONTENTS

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

2. PART NAMES AND FUNCTIONS······················3

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

4. NOISE CRITERIA CURVES·······························5

5. OUTLINES AND DIMENSIONS·························6

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

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

8. PERFORMANCE CURVES································9

9. ACTUA TOR CONTROL····································19

10. SERVICE FUNCTIONS·····································20

11. TROUBLESHOOTING······································20

12. DISASSEMBLY INSTRUCTIONS·····················27

13. PARTS LIST······················································30

14. RoHS PARTS LIST···········································32

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.

Revision A:

• MUH-GA20VB- and MUH-GA25VB- have been added.

E2E2

Revision B:

• MUH-GA35VB- has been added.

1

MUH-A07YV- ➔MUH-GA20VB-

1. Indication of capacity has been changed. (BTU base ➔ kw)

2. Dimension of outdoor unit has been changed. (W780mm x H540mm x D255mm ➔ W800mm x H550mm x D285mm)

3. Stop valve cover has been added.

4. Outdoor fan motor has been changed. (RC6V20-AB ➔ RA6V21-AD)

5. Outdoor fan motor capacitor has been changed.

6. Compressor capacitor has been changed.

7. Outdoor heat exchanger has been changed. (L-BEND ➔ FLAT)

MUH-A09YV- ➔MUH-GA25VB-

1. Indication of capacity has been changed. (BTU base ➔ kw)

2. Dimension of outdoor unit has been changed. (W780mm x H540mm x D255mm ➔ W800mm x H550mm x D285mm)

3. Stop valve cover has been added.

4. Outdoor fan motor has been changed. (RA6V33-FB ➔ RA6V33-KB)

5. Outdoor fan motor capacitor has been changed.

6. Compressor capacitor has been changed.

7. Outdoor heat exchanger has been changed. (2 Row ➔ 1 Row)

E3

TECHNICAL CHANGES

E1E1

E1E1

MUH-A12YV- ➔MUH-GA35VB-

1. Indication of capacity has been changed. (BTU base ➔ kw)

2. Dimension of outdoor unit has been changed. (W780mm x H540mm x D255mm ➔ W800mm x H550mm x D285mm)

3. Stop valve cover has been added.

4. Outdoor fan motor has been changed. (RA6V33-FB ➔ RA6V33-KB)

5. Outdoor fan motor capacitor has been changed.

6. Compressor capacitor has been changed.

7. Size of stop valve (gas) has been changed.([12.7 ➔ [9.52)

8. Outdoor heat exchanger has been changed. (2 Row ➔ 1 Row)

MUH-GA20VB- ➔MUH-GA20VB-

1. Compressor has been changed. (BN092VHST ➔ KN092VDMHC)

2. Compressor capacitor has been changed.

3. Capillary tube has been changed.

4. Refrigerant filling capacity has been changed.

5. Deicer P.C. board has been changed.

MUH-GA25VB- ➔MUH-GA25VB-

1. Compressor has been changed. (RN104VHSHT ➔ KN104VTMHC)

2. Compressor capacitor has been changed.

3. Capillary tube has been changed.

4. Refrigerant filling capacity has been changed.

5. Deicer P.C. board has been changed.

MUH-GA35VB- ➔MUH-GA35VB-

1. Outdoor heat exchanger has been changed. (1 row ➔ 2 row)

2. Refrigerant filling capacity has been changed.

3. Outdoor unit weight has been changed. (35 kg ➔ 39 kg)

E1E1

E2E1

E2E1

E3E1

2

2

( )

Air inlet

Air outlet

Drain outlet

Piping

Drain hose

back : MUH-GA20VB
back and side : MUH-GA25VB
MUH-GA35VB

Drain socket

1

<Outdoor unit: MUH type>

1

Capacity
Dehumidification
Outdoor air flow
Power outlet
Running current
Power input
Auxiliary heater
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
Fan speed
Fan speed regulator
Refrigerant filling
capacity (R410A)
Refrigeration oil (Model)

kW

R/h

K /h

A
A

W

A(kW)

%

A
A
A

W

"

"

mm

kg

dB

rpm

kg
cc

MUH-GA20VB -

E1

Single phase

230V,50Hz

1,800

10

—

21

0.25

RN092VHSHT

600
C-R 3.87
C-S 6.14

RA6V21-AD

WHT-BLK 366

BLK-RED 274
800o550o285

32
47

745

1

0.65

350 (NEO22)

Cooling

2.3

0.9

3.00
680

99

2.76

3.22

Heating

2.5

—

2.86
655

100

2.62

3.62

Compressor

Electrical

data

Fan

motor

Special

remarks

Capacity

Coefficient of performance (C.O.P)

Outdoor unit power supply

Function

Outdoor model

MUH-GA20VB -

E2

Single phase

230V,50Hz

1,800

10

—

15.5

0.25

KN092VDMHC

650
C-R 3.62
C-S 5.40

RA6V21-AD
WHT-BLK 366
BLK-RED 274

800o550o285

29
47

745

1

0.60

350 (NEO22)

Cooling

2.3

0.9

3.00
680

99

2.76

3.22

Heating

2.5

—

2.86
655

100

2.62

3.62

PART NAMES AND FUNCTIONS

OUTDOOR UNIT

MUH-GA20VB
MUH-GA25VB
MUH-GA35VB

3

SPECIFICATION

ACCESSORIES

MUH-GA20VB
MUH-GA25VB
MUH-GA35VB

NOTE: Test conditions are based on ISO 5151.

Cooling : Indoor DB27°C WB19°C Heating : Indoor DB20°C
Indoor-Outdoor piping length : 5m

Outdoor DB35°C WB24°C Outdoor DB 7°C/WB 6°C

3

Capacity
Dehumidification
Outdoor air flow
Power outlet
Running current
Power input
Auxiliary heater
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

Fan speed
Fan speed regulator
Refrigerant filling
capacity (R410A)
Refrigeration oil (Model)

kW

R/h

K /h

A
A

W

A(kW)

%

A
A
A

W

"

"

mm

kg

dB

rpm

kg
cc

MUH-GA25VB

-

E2

Single phase

230V,50Hz

1,902

10

—

19

0.33

KN104VTMHC

700
C-R 3.62
C-S 5.40

RA6V33-KB
WHT-BLK 215
BLK-RED 307

800o550o285

30
49

855

1

0.65

350 (NEO22)

Cooling

2.65

1.1

3.43
785

100

3.10

3.23

Heating

3.0

—

3.43
785

100

3.10

3.66

Compressor

Electrical

data

Fan

motor

Special

remarks

Capacity

Coefficient of performance (C.O.P)

Outdoor unit power supply

Function

Outdoor model

MUH-GA25VB

-

E1

Single phase

230V,50Hz

1,902

10

—

22

0.33

RN104VHSHT

700
C-R 3.40
C-S 4.56

RA6V33-KB
WHT-BLK 215
BLK-RED 307

800o550o285

32
49

855

1

0.80

350 (NEO22)

Cooling

2.65

1.1

3.43
785

100

3.10

3.23

Heating

3.0

—

3.43
785

100

3.10

3.66

MUH-GA35VB

-

E1

Single phase

230V,50Hz

1,902

10

—

27

0.33

RN135VHSHT

900
C-R 2.79
C-S 3.36

RA6V33-KB
WHT-BLK 215
BLK-RED 307

800o550o285

35
49

855

1

0.80

620 (NEO22)

Cooling

3.5

1.7

4.65

1,050

98

4.32

3.21

Heating

3.7

—

4.34
980

98

4.01

3.63

MUH-GA35VB

-

E3

Single phase

230V,50Hz

1,902

10

—

27

0.33

RN135VHSHT

900
C-R 2.79
C-S 3.36

RA6V33-KB
WHT-BLK 215
BLK-RED 307

800o550o285

39
49

855

1

1.05

620 (NEO22)

Cooling

3.5

1.7

4.65

1,050

98

4.32

3.21

Heating

3.7

—

4.34
980

98

4.01

3.63

NOTE: Test conditions are based on ISO 5151.

Cooling : Indoor DB27°C WB19°C Heating : Indoor DB20°C
Indoor-Outdoor piping length : 5m

Outdoor DB35°C WB24°C Outdoor DB 7°C/WB 6°C

4

90

80

70

60

50

40

30

20

10

63 125 250 500 1000 2000 4000 8000

APPROXIMATE
THRESHOLD OF
HEARING FOR
CONTINUOUS
NOISE

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

Test conditions,
Cooling :DB35: WB24:

Heating :DB 7: WB 6:

MUH-GA25VB
MUH-GA35VB

COOLING

FUNCTION

49

HEATING

SPL(dB

(A)) LINE

OUTDOOR UNIT

MICROPHONE

1m

90

80

70

60

50

40

30

20

10

63 125 250 500 1000 2000 4000 8000

APPROXIMATE
THRESHOLD OF
HEARING FOR
CONTINUOUS
NOISE

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

Test conditions,

Cooling :DB35: WB24:
Heating :DB 7: WB 6:

MUH-GA20VB

COOLING

FUNCTION

47

HEATING

SPL(dB

(A)) LINE

4

NOISE CRITERIA CURVES

5

5

10

69

800

302.5
500 Bolt pitch for installation

150

22.3

Handle

550

280

164.5

99.5

170.5

23

Service panel

Service port

285

344.5

44

400

Air in

Air out

Air in

17.5

Bolt pitch for

installation

304~325

40

Liquid refrigerant pipe joint
Refrigerant pipe (flared) [6.35

Gas refrigerant pipe joint
Refrigerant pipe (flared) [9.52

43-

35-

2 holes 10X21

(MUH-GA25

/GA35VB)

REQUIRED SPACE

Basically open 100mm or more
without any obstruction in front
and on both sides of the unit.

350mm or more

200mm or more

100mm or more

100mm or more

Open two sides of left,
right, or rear side.

Drain hole [42

OUTLINES AND DIMENSIONS

MUH-GA20VB MUH-GA25VB MUH-GA35VB

OUTDOOR UNIT

Unit: mm

6

6

SYMBOL

T61

TB1,TB2

21S4

52C

SYMBOL

MF

NR61

RT61

SR61,SR62

SYMBOL

C1

C65

DSAR

F61

MC

NAME

NAME NAME
COMPRESSOR CAPACITOR
OUTDOOR FAN CAPACITOR
SURGE ABSORBER
FUSE(T2AL250V)
COMPRESSOR(INNER PROTECTOR)

VARISTOR
DEFROST THERMISTOR
SOLID STATE RELAY

TRANSFORMER
TERMINAL BLOCK
R.V. COIL
COMPRESSOR CONTACTOR

OUTDOOR FAN MOTOR
(INNER FUSE)

TAB20

PE

N

3

TB2

N

L

TB1

BRN

321

CN711

CN730

BLU

NR61

RT61

21S4

CN661

C65

123

SR61

SR62

CN721

T61

WHT

C

MC

S

R

RED
BLK

C1

F61

BRN

DSAR

CIRCUIT
BREAKER

BLU

POWER SUPPLY

~/N 230V 50Hz

12V

TO INDOOR

UNIT

CONNECTING

RED

BLK

GRN/YLW

3

52C

4

BLK

WHT

RED

MF

WIRING DIAGRAM

MUH-GA20VB MUH-GA25VB MUH-GA35VB

OUTDOOR UNIT

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.
/: Terminal block, : Connector

7

7

REFRIGERANT SYSTEM DIAGRAM

MUH-GA20VB MUH-GA25VB MUH-GA35VB-

OUTDOOR UNIT

Refrigerant pipe [ 9.52

(with heat insulator)

Stop valve
(with service

Flared connection

Flared connection

Refrigerant pipe [6.35

(with heat insulator)

port)

Strainer
#100

Stop valve

Capillary tube

[3.0x[1.4x700 (MUH-GA20VB - )
[3.0x[1.4x900 (MUH-GA20VB - )
[3.0x[1.4x1000(MUH-GA25VB - )
[3.0x[1.6x1500(MUH-GA25VB - )
[3.0x[1.4x500 (MUH-GA35VB - )

Capillary tube

[3.0x[1.4x500 (MUH-GA20VB - )
[3.0x[1.4x300 (MUH-GA20VB - , MUH-GA35VB - )
[3.0x[1.4x600 (MUH-GA25VB - )
[3.0x[1.6x750 (MUH-GA25VB - )

E1

4-way valve

Muffler

Check valve

Defrost
thermistor
RT61

Compressor

Unit:mm

Outdoor
heat
exchanger

E1
E2
E1
E2

E1

R.V. coil
heating ON
cooling OFF

E1

E1E2
E1
E2

MUH-GA35VB-

OUTDOOR UNIT

E3

Refrigerant pipe [ 9.52

(with heat insulator)

Flared connection

Flared connection

Refrigerant pipe [6.35

(with heat insulator)

Stop valve
(with service
port)

Strainer
#100

Stop valve

4-way valve

Muffler

Check valve

Capillary tube
[3.0x[1.4x400

8

Compressor

Outdoor
heat
exchanger

Capillary tube
[3.0x[1.8x600
(2 pcs)

Capillary tube
[3.0x[1.4x350

R.V. coil
heating ON
cooling OFF

Defrost
thermistor

RT61
Refrigerant flow in cooling
Refrigerant flow in heating

MAX. REFRIGERANT PIPING LENGTH

Refrigerant piping : m

Model

Max. lengthAMax. height

B

Piping size O.D : mm

Gas

Liquid

Length of connecting pipe : m
Indoor unit

Outdoor unit

MUH-GA20VB
MUH-GA25VB

MUH-GA35VB

20

25

10

9.52

MAX. HEIGHT DIFFERENCE

Indoor
unit

Refrigerant Piping

Max. height
B

Max. length

A

ADDITIONAL REFRIGERANT CHARGE(R410A : g)

Model

MUH-GA20VB -

MUH-GA20VB -

MUH-GA25VB ­MUH-GA25VB -

MUH-GA35VB ­MUH-GA35VB -

Outdoor unit precharged

E1

E2

E1

E2
E1

E3

650
600
800
650
800

1050

7m

0

Gas 0.43

6.35
Liquid 0.5

Outdoor unit

Refrigerant piping length (one way)

10m

60

15m

160

Calculation : Xg = 20g/m x (A-7)m

20m

260

Gas 0

Liquid 0

25m

360

8

PERFORMANCE CURVES

MUH-GA20VB MUH-GA25VB MUH-GA35VB

The standard specifications apply only to the operation of the air conditioner under normal conditions, since operating condi-

tions vary according to the areas where these units are installed. The following information has been provided to clarify the
operating characteristics of the air conditioner under the conditions indicated by the performance curve.

(1) GUARANTEED VOLTAGE

198~264V

(2) AIR FLOW

Air flow should be set at MAX.

(3) MAIN READINGS

(1) Indoor intake air wet-bulb temperature : °CWB
(2) Indoor outlet air wet-bulb temperature : °CWB
(3) Outdoor intake air dry-bulb temperature : °CDB
(4) Total input: W
(5) Indoor intake air dry-bulb temperature : °CDB
(6) Outdoor intake air wet-bulb temperature : °CWB
(7) Total input : W
Indoor air wet/dry-bulb temperature difference on the left side of the chart on page 10 shows the difference between the
indoor intake air wet/dry-bulb temperature and the indoor outlet air wet/dry-bulb temperature for your reference at service.

Cooling

}

Heating

}

9

MSC-GA20VB

MUH-GA20VB

MUH-GA35VB

MSC-GA35VB

MUH-GA25VB

MSC-GA25VB

8.5

7.8

7.1

6.4

5.8

5.1

10.0

9.2

8.3

7.5

6.8

6.0

11.0

10.0

9.1

8.2

7.4

6.5

20.0

18.5

16.9

15.4

13.9

12.3

10.8

9.2

19.2

17.8

16.3

14.8

13.3

11.8

10.4

8.9

MSC-GA20VB

MUH-GA20VB

MUH-GA25VB

MSC-GA25VB

MUH-GA35VB

MSC-GA35VB

24.0

22.1

20.3

18.4

16.6

14.7

12.9

11.1

How to measure the indoor air wet-bulb/dry-bulb temperature difference

1. Attach at least 2 sets of wet-and dry-bulb thermometers to the indoor air intake as shown in the figure, and at least 2 sets
of wet-and dry-bulb thermometers to the indoor air outlet. The thermometers must be attached to the position where air
speed is high.

2. Attach at least 2 sets of wet-and dry-bulb thermometers to the outdoor air intake.
Cover the thermometers to prevent direct rays of the sun.

3. Check that the air filter is cleaned.

4. Open windows and doors of room.

5. Press the EMERGENCY OPERATION switch once(twice) to start the EMERGENCY COOL

(HEAT) MODE.

6. When system stabilizes after more than 15 minutes, measure temperature and take an average temperature.

7. 10 minutes later, measure temperature again and check that the temperature does not change.

INDOOR UNIT

Wet-and dry-bulb
thermometers

8-1.CAPACITY AND THE INPUT CURVES

OUTDOOR UNIT

Wet-and dry-bulb
thermometers

NOTE:The above curves are for the heating operation without any frost.

10

8-2.OUTDOOR LOW PRESSURE AND OUTDOOR UNIT CURRENT

18 32

7

8

9

10

11

12

13

230V

15 20

50

25
6030 70(%)

35(:)

0.7

0.8

0.9

1.0

1.1

1.2

1.3

15 20

50

25
60

30
70(%)

35(:)

1

2

4

3

18 32

230V

18 32

230V

15 20

50

25
6030 70(%)

35(:)

0.7

0.8

0.9

1.0

1.1

1.2

1.3

7

8

9

10

11

12

13

15 20

50

25
60

30
70(%)

35(:)

1

2

4

3

18 32

230V

18 32

230V

15 20

50

25
60

30

70(%)

35(:)

0.7

0.8

0.9

1.0

1.1

1.2

1.3

7

8

9

10

11

12

13

15 20

50

25
6030 70(%)

35(:)

3

4

5

6

18 32

230V

COOL operation

① Both indoor and outdoor unit are under the same temperature/humidity condition.

Dry-bulb temperature

20
25

Relative humidity(%)

50
60

30 70

➁ Air flow should be set at MAX.
③ 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] )

(kgf/F[Gauge])(MPa[Gauge])

Outdoor low pressure

Ambient temperature(˚C)
Ambient humidity(%)

(kgf/F[Gauge])(MPa[Gauge])

Outdoor unit current (A)

MUH-GA25VB

MUH-GA20VBMUH-GA20VB

Ambient temperature(˚C)
Ambient humidity(%)

MUH-GA25VB

Outdoor low pressure

Ambient temperature(˚C)
Ambient humidity(%)

(kgf/F[Gauge])(MPa[Gauge])

Outdoor low pressure

MUH-GA35VB

Ambient temperature(˚C)
Ambient humidity(%)

Outdoor unit current (A)

Ambient temperature(˚C)
Ambient humidity(%)

MUH-GA35VB

Outdoor unit current (A)

Ambient temperature(˚C)
Ambient humidity(%)

11

HEAT operation

7

21

230V

5 10152025

3

4

5

6

(:)

7

21

230V

(:)

5 10152025

2

3

4

5

7

21

230V

5 10152025

2

3

4

5

(:)

Condition indoor:Dry bulb temperature 20.0°C

Wet bulb temperature 14.5°C

Outdoor:Dry bulb temperature 7,15,20°C

Wet bulb temperature 6,12,14.5°C

MUH-GA20VB

Outdoor unit current (A)

Ambient temperature(˚C)

MUH-GA35VB

MUH-GA25VB

Outdoor unit current (A)

Ambient temperature(˚C)

Outdoor unit current (A)

Ambient temperature(˚C)

12

PERFORMANCE DATA

21 18 2.70 1.51 0.56 572 2.59 1.45 0.56 601 2.48 1.39 0.56 629 2.39 1.34 0.56 658
21 20 2.82 1.24 0.44 601 2.70 1.19 0.44 636 2.62 1.15 0.44 651 2.53 1.11 0.44 679
22 18 2.70 1.62 0.60 572 2.59 1.55 0.60 601 2.48 1.49 0.60 629 2.39 1.44 0.60 658
22 20 2.82 1.35 0.48 601 2.70 1.30 0.48 636 2.62 1.26 0.48 651 2.53 1.21 0.48 679
22 22 2.93 1.06 0.36 622 2.83 1.02 0.36 661 2.76 0.99 0.36 679 2.65 0.95 0.36 708
23 18 2.70 1.73 0.64 572 2.59 1.66 0.64 601 2.48 1.59 0.64 629 2.39 1.53 0.64 658
23 20 2.82 1.47 0.52 601 2.70 1.41 0.52 636 2.62 1.36 0.52 651 2.53 1.32 0.52 679
23 22 2.93 1.17 0.40 622 2.83 1.13 0.40 661 2.76 1.10 0.40 679 2.65 1.06 0.40 708
24 18 2.70 1.84 0.68 572 2.59 1.76 0.68 601 2.48 1.69 0.68 629 2.39 1.63 0.68 658
24 20 2.82 1.58 0.56 601 2.70 1.51 0.56 636 2.62 1.47 0.56 651 2.53 1.42 0.56 679
24 22 2.93 1.29 0.44 622 2.83 1.24 0.44 661 2.76 1.21 0.44 679 2.65 1.16 0.44 708
24 24 3.08 0.99 0.32 651 2.97 0.95 0.32 686 2.90 0.93 0.32 708 2.81 0.90 0.32 744
25 18 2.70 1.95 0.72 572 2.59 1.86 0.72 601 2.48 1.79 0.72 629 2.39 1.72 0.72 658
25 20 2.82 1.69 0.60 601 2.70 1.62 0.60 636 2.62 1.57 0.60 651 2.53 1.52 0.60 679
25 22 2.93 1.41 0.48 622 2.83 1.36 0.48 661 2.76 1.32 0.48 679 2.65 1.27 0.48 708
25 24 3.08 1.11 0.36 651 2.97 1.07 0.36 686 2.90 1.04 0.36 708 2.81 1.01 0.36 744
26 18 2.70 2.05 0.76 572 2.59 1.97 0.76 601 2.48 1.89 0.76 629 2.39 1.82 0.76 658
26 20 2.82 1.80 0.64 601 2.70 1.73 0.64 636 2.62 1.68 0.64 651 2.53 1.62 0.64 679
26 22 2.93 1.52 0.52 622 2.83 1.47 0.52 661 2.76 1.44 0.52 679 2.65 1.38 0.52 708
26 24 3.08 1.23 0.40 651 2.97 1.19 0.40 686 2.90 1.16 0.40 708 2.81 1.12 0.40 744
26 26 3.17 0.89 0.28 686 3.08 0.86 0.28 722 3.04 0.85 0.28 744 2.94 0.82 0.28 765
27 18 2.70 2.16 0.80 572 2.59 2.07 0.80 601 2.48 1.99 0.80 629 2.39 1.91 0.80 658
27 20 2.82 1.92 0.68 601 2.70 1.84 0.68 636 2.62 1.78 0.68 651 2.53 1.72 0.68 679
27 22 2.93 1.64 0.56 622 2.83 1.58 0.56 661 2.76 1.55 0.56 679 2.65 1.48 0.56 708
27 24 3.08 1.36 0.44 651 2.97 1.31 0.44 686 2.90 1.28 0.44 708 2.81 1.23 0.44 744
27 26 3.17 1.02 0.32 686 3.08 0.99 0.32 722 3.04 0.97 0.32 744 2.94 0.94 0.32 765
28 18 2.70 2.27 0.84 572 2.59 2.17 0.84 601 2.48 2.09 0.84 629 2.39 2.01 0.84 658
28 20 2.82 2.03 0.72 601 2.70 1.95 0.72 636 2.62 1.89 0.72 651 2.53 1.82 0.72 679
28 22 2.93 1.76 0.60 622 2.83 1.70 0.60 661 2.76 1.66 0.60 679 2.65 1.59 0.60 708
28 24 3.08 1.48 0.48 651 2.97 1.42 0.48 686 2.90 1.39 0.48 708 2.81 1.35 0.48 744
28 26 3.17 1.14 0.36 686 3.08 1.11 0.36 722 3.04 1.09 0.36 744 2.94 1.06 0.36 765
29 18 2.70 2.38 0.88 572 2.59 2.28 0.88 601 2.48 2.19 0.88 629 2.39 2.10 0.88 658
29 20 2.82 2.14 0.76 601 2.70 2.05 0.76 636 2.62 1.99 0.76 651 2.53 1.92 0.76 679
29 22 2.93 1.88 0.64 622 2.83 1.81 0.64 661 2.76 1.77 0.64 679 2.65 1.69 0.64 708
29 24 3.08 1.60 0.52 651 2.97 1.54 0.52 686 2.90 1.51 0.52 708 2.81 1.46 0.52 744
29 26 3.17 1.27 0.40 686 3.08 1.23 0.40 722 3.04 1.21 0.40 744 2.94 1.18 0.40 765
30 18 2.70 2.49 0.92 572 2.59 2.38 0.92 601 2.48 2.29 0.92 629 2.39 2.20 0.92 658
30 20 2.82 2.25 0.80 601 2.70 2.16 0.80 636 2.62 2.10 0.80 651 2.53 2.02 0.80 679
30 22 2.93 1.99 0.68 622 2.83 1.92 0.68 661 2.76 1.88 0.68 679 2.65 1.80 0.68 708
30 24 3.08 1.73 0.56 651 2.97 1.66 0.56 686 2.90 1.62 0.56 708 2.81 1.57 0.56 744
30 26 3.17 1.40 0.44 686 3.08 1.36 0.44 722 3.04 1.34 0.44 744 2.94 1.30 0.44 765
31 18 2.70 2.59 0.96 572 2.59 2.48 0.96 601 2.48 2.38 0.96 629 2.39 2.30 0.96 658
31 20 2.82 2.37 0.84 601 2.70 2.27 0.84 636 2.62 2.20 0.84 651 2.53 2.13 0.84 679
31 22 2.93 2.11 0.72 622 2.83 2.04 0.72 661 2.76 1.99 0.72 679 2.65 1.90 0.72 708
31 24 3.08 1.85 0.60 651 2.97 1.78 0.60 686 2.90 1.74 0.60 708 2.81 1.68 0.60 744
31 26 3.17 1.52 0.48 686 3.08 1.48 0.48 722 3.04 1.46 0.48 744 2.94 1.41 0.48 765
32 18 2.70 2.70 1.00 572 2.59 2.59 1.00 601 2.48 2.48 1.00 629 2.39 2.39 1.00 658
32 20 2.82 2.48 0.88 601 2.70 2.38 0.88 636 2.62 2.31 0.88 651 2.53 2.23 0.88 679
32 22 2.93 2.23 0.76 622 2.83 2.15 0.76 661 2.76 2.10 0.76 679 2.65 2.01 0.76 708
32 24 3.08 1.97 0.64 651 2.97 1.90 0.64 686 2.90 1.85 0.64 708 2.81 1.80 0.64 744
32 26 3.17 1.65 0.52 686 3.08 1.60 0.52 722 3.04 1.58 0.52 744 2.94 1.53 0.52 765

INDOOR

DB(:)

INDOOR

WB(:)

OUTDOOR DB(:)

21 2725

Q SHC SHF INPUT Q SHC SHF INPUT Q SHC SHF INPUT30Q SHC SHF INPUT

CAPACITY : 2.3(kW) SHF : 0.74 INPUT : 715(W)

COOL operation (230V)

MSC-GA20VB : MUH-GA20VB

NOTE Q :Total capacity (kW) SHF :Sensible heat factor DB :Dry-bulb temperature

SHC :Sensible heat capacity (kW) INPUT :Total power input (W) WB :Wet-bulb temperature

13

PERFORMANCE DATA

21 18 2.25 1.26 0.56 701 2.07 1.16 0.56 744 1.99 1.11 0.56 758
21 20 2.37 1.04 0.44 729 2.21 0.97 0.44 765 2.13 0.94 0.44 787
22 18 2.25 1.35 0.60 701 2.07 1.24 0.60 744 1.99 1.19 0.60 758
22 20 2.37 1.14 0.48 729 2.21 1.06 0.48 765 2.13 1.02 0.48 787
22 22 2.51 0.90 0.36 758 2.35 0.84 0.36 801 2.27 0.82 0.36 815
23 18 2.25 1.44 0.64 701 2.07 1.32 0.64 744 1.99 1.27 0.64 758
23 20 2.37 1.23 0.52 729 2.21 1.15 0.52 765 2.13 1.11 0.52 787
23 22 2.51 1.00 0.40 758 2.35 0.94 0.40 801 2.27 0.91 0.40 815
24 18 2.25 1.53 0.68 701 2.07 1.41 0.68 744 1.99 1.35 0.68 758
24 20 2.37 1.33 0.56 729 2.21 1.24 0.56 765 2.13 1.19 0.56 787
24 22 2.51 1.10 0.44 758 2.35 1.03 0.44 801 2.27 1.00 0.44 815
24 24 2.65 0.85 0.32 787 2.48 0.79 0.32 822 2.42 0.77 0.32 840
25 18 2.25 1.62 0.72 701 2.07 1.49 0.72 744 1.99 1.43 0.72 758
25 20 2.37 1.42 0.60 729 2.21 1.32 0.60 765 2.13 1.28 0.60 787
25 22 2.51 1.20 0.48 758 2.35 1.13 0.48 801 2.27 1.09 0.48 815
25 24 2.65 0.95 0.36 787 2.48 0.89 0.36 822 2.42 0.87 0.36 840
26 18 2.25 1.71 0.76 701 2.07 1.57 0.76 744 1.99 1.51 0.76 758
26 20 2.37 1.52 0.64 729 2.21 1.41 0.64 765 2.13 1.36 0.64 787
26 22 2.51 1.30 0.52 758 2.35 1.22 0.52 801 2.27 1.18 0.52 815
26 24 2.65 1.06 0.40 787 2.48 0.99 0.40 822 2.42 0.97 0.40 840
26 26 2.78 0.78 0.28 815 2.62 0.73 0.28 851 2.54 0.71 0.28 869
27 18 2.25 1.80 0.80 701 2.07 1.66 0.80 744 1.99 1.59 0.80 758
27 20 2.37 1.61 0.68 729 2.21 1.50 0.68 765 2.13 1.45 0.68 787
27 22 2.51 1.40 0.56 758 2.35 1.31 0.56 801 2.27 1.27 0.56 815
27 24 2.65 1.16 0.44 787 2.48 1.09 0.44 822 2.42 1.06 0.44 840
27 26 2.78 0.89 0.32 815 2.62 0.84 0.32 851 2.54 0.81 0.32 869
28 18 2.25 1.89 0.84 701 2.07 1.74 0.84 744 1.99 1.67 0.84 758
28 20 2.37 1.71 0.72 729 2.21 1.59 0.72 765 2.13 1.53 0.72 787
28 22 2.51 1.50 0.60 758 2.35 1.41 0.60 801 2.27 1.36 0.60 815
28 24 2.65 1.27 0.48 787 2.48 1.19 0.48 822 2.42 1.16 0.48 840
28 26 2.78 1.00 0.36 815 2.62 0.94 0.36 851 2.54 0.91 0.36 869
29 18 2.25 1.98 0.88 701 2.07 1.82 0.88 744 1.99 1.75 0.88 758
29 20 2.37 1.80 0.76 729 2.21 1.68 0.76 765 2.13 1.62 0.76 787
29 22 2.51 1.60 0.64 758 2.35 1.50 0.64 801 2.27 1.45 0.64 815
29 24 2.65 1.38 0.52 787 2.48 1.29 0.52 822 2.42 1.26 0.52 840
29 26 2.78 1.11 0.40 815 2.62 1.05 0.40 851 2.54 1.02 0.40 869
30 18 2.25 2.07 0.92 701 2.07 1.90 0.92 744 1.99 1.83 0.92 758
30 20 2.37 1.90 0.80 729 2.21 1.77 0.80 765 2.13 1.70 0.80 787
30 22 2.51 1.70 0.68 758 2.35 1.60 0.68 801 2.27 1.54 0.68 815
30 24 2.65 1.48 0.56 787 2.48 1.39 0.56 822 2.42 1.35 0.56 840
30 26 2.78 1.22 0.44 815 2.62 1.15 0.44 851 2.54 1.12 0.44 869
31 18 2.25 2.16 0.96 701 2.07 1.99 0.96 744 1.99 1.91 0.96 758
31 20 2.37 1.99 0.84 729 2.21 1.85 0.84 765 2.13 1.79 0.84 787
31 22 2.51 1.81 0.72 758 2.35 1.69 0.72 801 2.27 1.63 0.72 815
31 24 2.65 1.59 0.60 787 2.48 1.49 0.60 822 2.42 1.45 0.60 840
31 26 2.78 1.34 0.48 815 2.62 1.26 0.48 851 2.54 1.22 0.48 869
32 18 2.25 2.25 1.00 701 2.07 2.07 1.00 744 1.99 1.99 1.00 758
32 20 2.37 2.08 0.88 729 2.21 1.94 0.88 765 2.13 1.87 0.88 787
32 22 2.51 1.91 0.76 758 2.35 1.78 0.76 801 2.27 1.72 0.76 815
32 24 2.65 1.69 0.64 787 2.48 1.59 0.64 822 2.42 1.55 0.64 840
32 26 2.78 1.45 0.52 815 2.62 1.36 0.52 851 2.54 1.32 0.52 869

INDOOR

DB(:)

INDOOR

WB(:)

OUTDOOR DB(:)

35 4340

Q SHC SHF INPUT Q SHC SHF INPUT Q SHC SHF INPUT

CAPACITY : 2.3(kW) SHF : 0.74 INPUT : 715(W)

COOL operation (230V)

MSC-GA20VB : MUH-GA20VB

NOTE Q :Total capacity (kW) SHF :Sensible heat factor DB :Dry-bulb temperature

SHC :Sensible heat capacity (kW) INPUT :Total power input (W) WB :Wet-bulb temperature

14

PERFORMANCE DATA

21 18 3.11 1.62 0.52 656 2.98 1.55 0.52 689 2.86 1.49 0.52 722 2.76 1.43 0.52 754
21 20 3.25 1.30 0.40 689 3.11 1.25 0.40 730 3.02 1.21 0.40 746 2.92 1.17 0.40 779
22 18 3.11 1.74 0.56 656 2.98 1.67 0.56 689 2.86 1.60 0.56 722 2.76 1.54 0.56 754
22 20 3.25 1.43 0.44 689 3.11 1.37 0.44 730 3.02 1.33 0.44 746 2.92 1.28 0.44 779
22 22 3.38 1.08 0.32 713 3.26 1.04 0.32 759 3.18 1.02 0.32 779 3.05 0.98 0.32 812
23 18 3.11 1.87 0.60 656 2.98 1.79 0.60 689 2.86 1.72 0.60 722 2.76 1.65 0.60 754
23 20 3.25 1.56 0.48 689 3.11 1.49 0.48 730 3.02 1.45 0.48 746 2.92 1.40 0.48 779
23 22 3.38 1.22 0.36 713 3.26 1.17 0.36 759 3.18 1.14 0.36 779 3.05 1.10 0.36 812
24 18 3.11 1.99 0.64 656 2.98 1.91 0.64 689 2.86 1.83 0.64 722 2.76 1.76 0.64 754
24 20 3.25 1.69 0.52 689 3.11 1.62 0.52 730 3.02 1.57 0.52 746 2.92 1.52 0.52 779
24 22 3.38 1.35 0.40 713 3.26 1.30 0.40 759 3.18 1.27 0.40 779 3.05 1.22 0.40 812
24 24 3.55 0.99 0.28 746 3.42 0.96 0.28 787 3.34 0.93 0.28 812 3.23 0.91 0.28 853
25 18 3.11 2.12 0.68 656 2.98 2.03 0.68 689 2.86 1.95 0.68 722 2.76 1.87 0.68 754
25 20 3.25 1.82 0.56 689 3.11 1.74 0.56 730 3.02 1.69 0.56 746 2.92 1.63 0.56 779
25 22 3.38 1.49 0.44 713 3.26 1.43 0.44 759 3.18 1.40 0.44 779 3.05 1.34 0.44 812
25 24 3.55 1.14 0.32 746 3.42 1.09 0.32 787 3.34 1.07 0.32 812 3.23 1.03 0.32 853
26 18 3.11 2.24 0.72 656 2.98 2.15 0.72 689 2.86 2.06 0.72 722 2.76 1.98 0.72 754
26 20 3.25 1.95 0.60 689 3.11 1.87 0.60 730 3.02 1.81 0.60 746 2.92 1.75 0.60 779
26 22 3.38 1.62 0.48 713 3.26 1.56 0.48 759 3.18 1.53 0.48 779 3.05 1.46 0.48 812
26 24 3.55 1.28 0.36 746 3.42 1.23 0.36 787 3.34 1.20 0.36 812 3.23 1.16 0.36 853
26 26 3.66 0.88 0.24 787 3.55 0.85 0.24 828 3.50 0.84 0.24 853 3.39 0.81 0.24 877
27 18 3.11 2.37 0.76 656 2.98 2.27 0.76 689 2.86 2.18 0.76 722 2.76 2.09 0.76 754
27 20 3.25 2.08 0.64 689 3.11 1.99 0.64 730 3.02 1.93 0.64 746 2.92 1.87 0.64 779
27 22 3.38 1.76 0.52 713 3.26 1.69 0.52 759 3.18 1.65 0.52 779 3.05 1.58 0.52 812
27 24 3.55 1.42 0.40 746 3.42 1.37 0.40 787 3.34 1.34 0.40 812 3.23 1.29 0.40 853
27 26 3.66 1.02 0.28 787 3.55 0.99 0.28 828 3.50 0.98 0.28 853 3.39 0.95 0.28 877
28 18 3.11 2.49 0.80 656 2.98 2.39 0.80 689 2.86 2.29 0.80 722 2.76 2.20 0.80 754
28 20 3.25 2.21 0.68 689 3.11 2.12 0.68 730 3.02 2.05 0.68 746 2.92 1.98 0.68 779
28 22 3.38 1.89 0.56 713 3.26 1.83 0.56 759 3.18 1.78 0.56 779 3.05 1.71 0.56 812
28 24 3.55 1.56 0.44 746 3.42 1.50 0.44 787 3.34 1.47 0.44 812 3.23 1.42 0.44 853
28 26 3.66 1.17 0.32 787 3.55 1.14 0.32 828 3.50 1.12 0.32 853 3.39 1.09 0.32 877
29 18 3.11 2.62 0.84 656 2.98 2.50 0.84 689 2.86 2.40 0.84 722 2.76 2.32 0.84 754
29 20 3.25 2.34 0.72 689 3.11 2.24 0.72 730 3.02 2.18 0.72 746 2.92 2.10 0.72 779
29 22 3.38 2.03 0.60 713 3.26 1.96 0.60 759 3.18 1.91 0.60 779 3.05 1.83 0.60 812
29 24 3.55 1.70 0.48 746 3.42 1.64 0.48 787 3.34 1.60 0.48 812 3.23 1.55 0.48 853
29 26 3.66 1.32 0.36 787 3.55 1.28 0.36 828 3.50 1.26 0.36 853 3.39 1.22 0.36 877
30 18 3.11 2.74 0.88 656 2.98 2.62 0.88 689 2.86 2.52 0.88 722 2.76 2.43 0.88 754
30 20 3.25 2.47 0.76 689 3.11 2.37 0.76 730 3.02 2.30 0.76 746 2.92 2.22 0.76 779
30 22 3.38 2.16 0.64 713 3.26 2.09 0.64 759 3.18 2.04 0.64 779 3.05 1.95 0.64 812
30 24 3.55 1.85 0.52 746 3.42 1.78 0.52 787 3.34 1.74 0.52 812 3.23 1.68 0.52 853
30 26 3.66 1.46 0.40 787 3.55 1.42 0.40 828 3.50 1.40 0.40 853 3.39 1.36 0.40 877
31 18 3.11 2.86 0.92 656 2.98 2.74 0.92 689 2.86 2.63 0.92 722 2.76 2.54 0.92 754
31 20 3.25 2.60 0.80 689 3.11 2.49 0.80 730 3.02 2.42 0.80 746 2.92 2.33 0.80 779
31 22 3.38 2.30 0.68 713 3.26 2.22 0.68 759 3.18 2.16 0.68 779 3.05 2.07 0.68 812
31 24 3.55 1.99 0.56 746 3.42 1.91 0.56 787 3.34 1.87 0.56 812 3.23 1.81 0.56 853
31 26 3.66 1.61 0.44 787 3.55 1.56 0.44 828 3.50 1.54 0.44 853 3.39 1.49 0.44 877
32 18 3.11 2.99 0.96 656 2.98 2.86 0.96 689 2.86 2.75 0.96 722 2.76 2.65 0.96 754
32 20 3.25 2.73 0.84 689 3.11 2.62 0.84 730 3.02 2.54 0.84 746 2.92 2.45 0.84 779
32 22 3.38 2.43 0.72 713 3.26 2.35 0.72 759 3.18 2.29 0.72 779 3.05 2.19 0.72 812
32 24 3.55 2.13 0.60 746 3.42 2.05 0.60 787 3.34 2.00 0.60 812 3.23 1.94 0.60 853
32 26 3.66 1.76 0.48 787 3.55 1.70 0.48 828 3.50 1.68 0.48 853 3.39 1.63 0.48 877

INDOOR

DB(:)

INDOOR

WB(:)

OUTDOOR DB(:)

21 2725

Q SHC SHF INPUT Q SHC SHF INPUT Q SHC SHF INPUT30Q SHC SHF INPUT

CAPACITY : 2.65(kW) SHF : 0.70 INPUT : 820(W)

COOL operation (230V)

MSC-GA25VB : MUH-GA25VB

NOTE Q :Total capacity (kW) SHF :Sensible heat factor DB :Dry-bulb temperature

SHC :Sensible heat capacity (kW) INPUT :Total power input (W) WB :Wet-bulb temperature

15

PERFORMANCE DATA

21 18 2.60 1.35 0.52 804 2.39 1.24 0.52 853 2.29 1.19 0.52 869
21 20 2.73 1.09 0.40 836 2.54 1.02 0.40 877 2.45 0.98 0.40 902
22 18 2.60 1.45 0.56 804 2.39 1.34 0.56 853 2.29 1.28 0.56 869
22 20 2.73 1.20 0.44 836 2.54 1.12 0.44 877 2.45 1.08 0.44 902
22 22 2.89 0.92 0.32 869 2.70 0.86 0.32 918 2.61 0.84 0.32 935
23 18 2.60 1.56 0.60 804 2.39 1.43 0.60 853 2.29 1.38 0.60 869
23 20 2.73 1.31 0.48 836 2.54 1.22 0.48 877 2.45 1.18 0.48 902
23 22 2.89 1.04 0.36 869 2.70 0.97 0.36 918 2.61 0.94 0.36 935
24 18 2.60 1.66 0.64 804 2.39 1.53 0.64 853 2.29 1.47 0.64 869
24 20 2.73 1.42 0.52 836 2.54 1.32 0.52 877 2.45 1.27 0.52 902
24 22 2.89 1.16 0.40 869 2.70 1.08 0.40 918 2.61 1.04 0.40 935
24 24 3.05 0.85 0.28 902 2.86 0.80 0.28 943 2.78 0.78 0.28 964
25 18 2.60 1.77 0.68 804 2.39 1.62 0.68 853 2.29 1.56 0.68 869
25 20 2.73 1.53 0.56 836 2.54 1.42 0.56 877 2.45 1.37 0.56 902
25 22 2.89 1.27 0.44 869 2.70 1.19 0.44 918 2.61 1.15 0.44 935
25 24 3.05 0.98 0.32 902 2.86 0.92 0.32 943 2.78 0.89 0.32 964
26 18 2.60 1.87 0.72 804 2.39 1.72 0.72 853 2.29 1.65 0.72 869
26 20 2.73 1.64 0.60 836 2.54 1.53 0.60 877 2.45 1.47 0.60 902
26 22 2.89 1.39 0.48 869 2.70 1.30 0.48 918 2.61 1.25 0.48 935
26 24 3.05 1.10 0.36 902 2.86 1.03 0.36 943 2.78 1.00 0.36 964
26 26 3.21 0.77 0.24 935 3.02 0.73 0.24 976 2.93 0.70 0.24 996
27 18 2.60 1.97 0.76 804 2.39 1.81 0.76 853 2.29 1.74 0.76 869
27 20 2.73 1.75 0.64 836 2.54 1.63 0.64 877 2.45 1.57 0.64 902
27 22 2.89 1.50 0.52 869 2.70 1.41 0.52 918 2.61 1.36 0.52 935
27 24 3.05 1.22 0.40 902 2.86 1.14 0.40 943 2.78 1.11 0.40 964
27 26 3.21 0.90 0.28 935 3.02 0.85 0.28 976 2.93 0.82 0.28 996
28 18 2.60 2.08 0.80 804 2.39 1.91 0.80 853 2.29 1.83 0.80 869
28 20 2.73 1.86 0.68 836 2.54 1.73 0.68 877 2.45 1.67 0.68 902
28 22 2.89 1.62 0.56 869 2.70 1.51 0.56 918 2.61 1.46 0.56 935
28 24 3.05 1.34 0.44 902 2.86 1.26 0.44 943 2.78 1.22 0.44 964
28 26 3.21 1.03 0.32 935 3.02 0.97 0.32 976 2.93 0.94 0.32 996
29 18 2.60 2.18 0.84 804 2.39 2.00 0.84 853 2.29 1.93 0.84 869
29 20 2.73 1.97 0.72 836 2.54 1.83 0.72 877 2.45 1.76 0.72 902
29 22 2.89 1.73 0.60 869 2.70 1.62 0.60 918 2.61 1.57 0.60 935
29 24 3.05 1.46 0.48 902 2.86 1.37 0.48 943 2.78 1.34 0.48 964
29 26 3.21 1.15 0.36 935 3.02 1.09 0.36 976 2.93 1.05 0.36 996
30 18 2.60 2.29 0.88 804 2.39 2.10 0.88 853 2.29 2.02 0.88 869
30 20 2.73 2.07 0.76 836 2.54 1.93 0.76 877 2.45 1.86 0.76 902
30 22 2.89 1.85 0.64 869 2.70 1.73 0.64 918 2.61 1.67 0.64 935
30 24 3.05 1.58 0.52 902 2.86 1.49 0.52 943 2.78 1.45 0.52 964
30 26 3.21 1.28 0.40 935 3.02 1.21 0.40 976 2.93 1.17 0.40 996
31 18 2.60 2.39 0.92 804 2.39 2.19 0.92 853 2.29 2.11 0.92 869
31 20 2.73 2.18 0.80 836 2.54 2.04 0.80 877 2.45 1.96 0.80 902
31 22 2.89 1.96 0.68 869 2.70 1.84 0.68 918 2.61 1.77 0.68 935
31 24 3.05 1.71 0.56 902 2.86 1.60 0.56 943 2.78 1.56 0.56 964
31 26 3.21 1.41 0.44 935 3.02 1.33 0.44 976 2.93 1.29 0.44 996
32 18 2.60 2.49 0.96 804 2.39 2.29 0.96 853 2.29 2.20 0.96 869
32 20 2.73 2.29 0.84 836 2.54 2.14 0.84 877 2.45 2.06 0.84 902
32 22 2.89 2.08 0.72 869 2.70 1.95 0.72 918 2.61 1.88 0.72 935
32 24 3.05 1.83 0.60 902 2.86 1.72 0.60 943 2.78 1.67 0.60 964
32 26 3.21 1.54 0.48 935 3.02 1.45 0.48 976 2.93 1.41 0.48 996

INDOOR

DB(:)

INDOOR

WB(:)

OUTDOOR DB(:)

35 4340

Q SHC SHF INPUT Q SHC SHF INPUT Q SHC SHF INPUT

CAPACITY : 2.65(kW) SHF : 0.70 INPUT : 820(W)

COOL operation (230V)

MSC-GA25VB : MUH-GA25VB

NOTE Q :Total capacity (kW) SHF :Sensible heat factor DB :Dry-bulb temperature

SHC :Sensible heat capacity (kW) INPUT :Total power input (W) WB :Wet-bulb temperature

16

PERFORMANCE DATA

21 18 4.11 1.97 0.48 872 3.94 1.89 0.48 916 3.78 1.81 0.48 959 3.64 1.75 0.48 1003
21 20 4.29 1.54 0.36 916 4.11 1.48 0.36 970 3.99 1.44 0.36 992 3.85 1.39 0.36 1036
22 18 4.11 2.14 0.52 872 3.94 2.05 0.52 916 3.78 1.97 0.52 959 3.64 1.89 0.52 1003
22 20 4.29 1.72 0.40 916 4.11 1.65 0.40 970 3.99 1.60 0.40 992 3.85 1.54 0.40 1036
22 22 4.46 1.25 0.28 948 4.31 1.21 0.28 1008 4.20 1.18 0.28 1036 4.03 1.13 0.28 1079
23 18 4.11 2.30 0.56 872 3.94 2.21 0.56 916 3.78 2.12 0.56 959 3.64 2.04 0.56 1003
23 20 4.29 1.89 0.44 916 4.11 1.81 0.44 970 3.99 1.76 0.44 992 3.85 1.69 0.44 1036
23 22 4.46 1.43 0.32 948 4.31 1.38 0.32 1008 4.20 1.34 0.32 1036 4.03 1.29 0.32 1079
24 18 4.11 2.47 0.60 872 3.94 2.36 0.60 916 3.78 2.27 0.60 959 3.64 2.18 0.60 1003
24 20 4.29 2.06 0.48 916 4.11 1.97 0.48 970 3.99 1.92 0.48 992 3.85 1.85 0.48 1036
24 22 4.46 1.61 0.36 948 4.31 1.55 0.36 1008 4.20 1.51 0.36 1036 4.03 1.45 0.36 1079
24 24 4.69 1.13 0.24 992 4.52 1.08 0.24 1046 4.41 1.06 0.24 1079 4.27 1.02 0.24 1134
25 18 4.11 2.63 0.64 872 3.94 2.52 0.64 916 3.78 2.42 0.64 959 3.64 2.33 0.64 1003
25 20 4.29 2.23 0.52 916 4.11 2.14 0.52 970 3.99 2.07 0.52 992 3.85 2.00 0.52 1036
25 22 4.46 1.79 0.40 948 4.31 1.72 0.40 1008 4.20 1.68 0.40 1036 4.03 1.61 0.40 1079
25 24 4.69 1.31 0.28 992 4.52 1.26 0.28 1046 4.41 1.23 0.28 1079 4.27 1.20 0.28 1134
26 18 4.11 2.80 0.68 872 3.94 2.68 0.68 916 3.78 2.57 0.68 959 3.64 2.48 0.68 1003
26 20 4.29 2.40 0.56 916 4.11 2.30 0.56 970 3.99 2.23 0.56 992 3.85 2.16 0.56 1036
26 22 4.46 1.96 0.44 948 4.31 1.89 0.44 1008 4.20 1.85 0.44 1036 4.03 1.77 0.44 1079
26 24 4.69 1.50 0.32 992 4.52 1.44 0.32 1046 4.41 1.41 0.32 1079 4.27 1.37 0.32 1134
26 26 4.83 0.97 0.20 1046 4.69 0.94 0.20 1101 4.62 0.92 0.20 1134 4.48 0.90 0.20 1166
27 18 4.11 2.96 0.72 872 3.94 2.84 0.72 916 3.78 2.72 0.72 959 3.64 2.62 0.72 1003
27 20 4.29 2.57 0.60 916 4.11 2.47 0.60 970 3.99 2.39 0.60 992 3.85 2.31 0.60 1036
27 22 4.46 2.14 0.48 948 4.31 2.07 0.48 1008 4.20 2.02 0.48 1036 4.03 1.93 0.48 1079
27 24 4.69 1.69 0.36 992 4.52 1.63 0.36 1046 4.41 1.59 0.36 1079 4.27 1.54 0.36 1134
27 26 4.83 1.16 0.24 1046 4.69 1.13 0.24 1101 4.62 1.11 0.24 1134 4.48 1.08 0.24 1166
28 18 4.11 3.13 0.76 872 3.94 2.99 0.76 916 3.78 2.87 0.76 959 3.64 2.77 0.76 1003
28 20 4.29 2.74 0.64 916 4.11 2.63 0.64 970 3.99 2.55 0.64 992 3.85 2.46 0.64 1036
28 22 4.46 2.32 0.52 948 4.31 2.24 0.52 1008 4.20 2.18 0.52 1036 4.03 2.09 0.52 1079
28 24 4.69 1.88 0.40 992 4.52 1.81 0.40 1046 4.41 1.76 0.40 1079 4.27 1.71 0.40 1134
28 26 4.83 1.35 0.28 1046 4.69 1.31 0.28 1101 4.62 1.29 0.28 1134 4.48 1.25 0.28 1166
29 18 4.11 3.29 0.80 872 3.94 3.15 0.80 916 3.78 3.02 0.80 959 3.64 2.91 0.80 1003
29 20 4.29 2.92 0.68 916 4.11 2.80 0.68 970 3.99 2.71 0.68 992 3.85 2.62 0.68 1036
29 22 4.46 2.50 0.56 948 4.31 2.41 0.56 1008 4.20 2.35 0.56 1036 4.03 2.25 0.56 1079
29 24 4.69 2.06 0.44 992 4.52 1.99 0.44 1046 4.41 1.94 0.44 1079 4.27 1.88 0.44 1134
29 26 4.83 1.55 0.32 1046 4.69 1.50 0.32 1101 4.62 1.48 0.32 1134 4.48 1.43 0.32 1166
30 18 4.11 3.45 0.84 872 3.94 3.31 0.84 916 3.78 3.18 0.84 959 3.64 3.06 0.84 1003
30 20 4.29 3.09 0.72 916 4.11 2.96 0.72 970 3.99 2.87 0.72 992 3.85 2.77 0.72 1036
30 22 4.46 2.68 0.60 948 4.31 2.58 0.60 1008 4.20 2.52 0.60 1036 4.03 2.42 0.60 1079
30 24 4.69 2.25 0.48 992 4.52 2.17 0.48 1046 4.41 2.12 0.48 1079 4.27 2.05 0.48 1134
30 26 4.83 1.74 0.36 1046 4.69 1.69 0.36 1101 4.62 1.66 0.36 1134 4.48 1.61 0.36 1166
31 18 4.11 3.62 0.88 872 3.94 3.47 0.88 916 3.78 3.33 0.88 959 3.64 3.20 0.88 1003
31 20 4.29 3.26 0.76 916 4.11 3.13 0.76 970 3.99 3.03 0.76 992 3.85 2.93 0.76 1036
31 22 4.46 2.86 0.64 948 4.31 2.76 0.64 1008 4.20 2.69 0.64 1036 4.03 2.58 0.64 1079
31 24 4.69 2.44 0.52 992 4.52 2.35 0.52 1046 4.41 2.29 0.52 1079 4.27 2.22 0.52 1134
31 26 4.83 1.93 0.40 1046 4.69 1.88 0.40 1101 4.62 1.85 0.40 1134 4.48 1.79 0.40 1166
32 18 4.11 3.78 0.92 872 3.94 3.62 0.92 916 3.78 3.48 0.92 959 3.64 3.35 0.92 1003
32 20 4.29 3.43 0.80 916 4.11 3.29 0.80 970 3.99 3.19 0.80 992 3.85 3.08 0.80 1036
32 22 4.46 3.03 0.68 948 4.31 2.93 0.68 1008 4.20 2.86 0.68 1036 4.03 2.74 0.68 1079
32 24 4.69 2.63 0.56 992 4.52 2.53 0.56 1046 4.41 2.47 0.56 1079 4.27 2.39 0.56 1134
32 26 4.83 2.13 0.44 1046 4.69 2.06 0.44 1101 4.62 2.03 0.44 1134 4.48 1.97 0.44 1166

INDOOR

DB(:)

INDOOR

WB(:)

OUTDOOR DB(:)

21 2725

Q SHC SHF INPUT Q SHC SHF INPUT Q SHC SHF INPUT30Q SHC SHF INPUT

CAPACITY : 3.5(kW) SHF : 0.66 INPUT : 1090(W)

COOL operation (230V)

MSC-GA35VB : MUH-GA35VB

NOTE Q :Total capacity (kW) SHF :Sensible heat factor DB :Dry-bulb temperature

SHC :Sensible heat capacity (kW) INPUT :Total power input (W) WB :Wet-bulb temperature

17

PERFORMANCE DATA

21 18 3.43 1.65 0.48 1068 3.15 1.51 0.48 1134 3.03 1.45 0.48 1155
21 20 3.61 1.30 0.36 1112 3.36 1.21 0.36 1166 3.24 1.17 0.36 1199
22 18 3.43 1.78 0.52 1068 3.15 1.64 0.52 1134 3.03 1.57 0.52 1155
22 20 3.61 1.44 0.40 1112 3.36 1.34 0.40 1166 3.24 1.30 0.40 1199
22 22 3.82 1.07 0.28 1155 3.57 1.00 0.28 1221 3.45 0.97 0.28 1243
23 18 3.43 1.92 0.56 1068 3.15 1.76 0.56 1134 3.03 1.70 0.56 1155
23 20 3.61 1.59 0.44 1112 3.36 1.48 0.44 1166 3.24 1.42 0.44 1199
23 22 3.82 1.22 0.32 1155 3.57 1.14 0.32 1221 3.45 1.10 0.32 1243
24 18 3.43 2.06 0.60 1068 3.15 1.89 0.60 1134 3.03 1.82 0.60 1155
24 20 3.61 1.73 0.48 1112 3.36 1.61 0.48 1166 3.24 1.55 0.48 1199
24 22 3.82 1.37 0.36 1155 3.57 1.29 0.36 1221 3.45 1.24 0.36 1243
24 24 4.03 0.97 0.24 1199 3.78 0.91 0.24 1254 3.68 0.88 0.24 1281
25 18 3.43 2.20 0.64 1068 3.15 2.02 0.64 1134 3.03 1.94 0.64 1155
25 20 3.61 1.87 0.52 1112 3.36 1.75 0.52 1166 3.24 1.68 0.52 1199
25 22 3.82 1.53 0.40 1155 3.57 1.43 0.40 1221 3.45 1.38 0.40 1243
25 24 4.03 1.13 0.28 1199 3.78 1.06 0.28 1254 3.68 1.03 0.28 1281
26 18 3.43 2.33 0.68 1068 3.15 2.14 0.68 1134 3.03 2.06 0.68 1155
26 20 3.61 2.02 0.56 1112 3.36 1.88 0.56 1166 3.24 1.81 0.56 1199
26 22 3.82 1.68 0.44 1155 3.57 1.57 0.44 1221 3.45 1.52 0.44 1243
26 24 4.03 1.29 0.32 1199 3.78 1.21 0.32 1254 3.68 1.18 0.32 1281
26 26 4.24 0.85 0.20 1243 3.99 0.80 0.20 1297 3.87 0.77 0.20 1324
27 18 3.43 2.47 0.72 1068 3.15 2.27 0.72 1134 3.03 2.18 0.72 1155
27 20 3.61 2.16 0.60 1112 3.36 2.02 0.60 1166 3.24 1.94 0.60 1199
27 22 3.82 1.83 0.48 1155 3.57 1.71 0.48 1221 3.45 1.65 0.48 1243
27 24 4.03 1.45 0.36 1199 3.78 1.36 0.36 1254 3.68 1.32 0.36 1281
27 26 4.24 1.02 0.24 1243 3.99 0.96 0.24 1297 3.87 0.93 0.24 1324
28 18 3.43 2.61 0.76 1068 3.15 2.39 0.76 1134 3.03 2.30 0.76 1155
28 20 3.61 2.31 0.64 1112 3.36 2.15 0.64 1166 3.24 2.07 0.64 1199
28 22 3.82 1.98 0.52 1155 3.57 1.86 0.52 1221 3.45 1.79 0.52 1243
28 24 4.03 1.61 0.40 1199 3.78 1.51 0.40 1254 3.68 1.47 0.40 1281
28 26 4.24 1.19 0.28 1243 3.99 1.12 0.28 1297 3.87 1.08 0.28 1324
29 18 3.43 2.74 0.80 1068 3.15 2.52 0.80 1134 3.03 2.42 0.80 1155
29 20 3.61 2.45 0.68 1112 3.36 2.28 0.68 1166 3.24 2.20 0.68 1199
29 22 3.82 2.14 0.56 1155 3.57 2.00 0.56 1221 3.45 1.93 0.56 1243
29 24 4.03 1.77 0.44 1199 3.78 1.66 0.44 1254 3.68 1.62 0.44 1281
29 26 4.24 1.36 0.32 1243 3.99 1.28 0.32 1297 3.87 1.24 0.32 1324
30 18 3.43 2.88 0.84 1068 3.15 2.65 0.84 1134 3.03 2.54 0.84 1155
30 20 3.61 2.60 0.72 1112 3.36 2.42 0.72 1166 3.24 2.33 0.72 1199
30 22 3.82 2.29 0.60 1155 3.57 2.14 0.60 1221 3.45 2.07 0.60 1243
30 24 4.03 1.93 0.48 1199 3.78 1.81 0.48 1254 3.68 1.76 0.48 1281
30 26 4.24 1.52 0.36 1243 3.99 1.44 0.36 1297 3.87 1.39 0.36 1324
31 18 3.43 3.02 0.88 1068 3.15 2.77 0.88 1134 3.03 2.66 0.88 1155
31 20 3.61 2.74 0.76 1112 3.36 2.55 0.76 1166 3.24 2.46 0.76 1199
31 22 3.82 2.44 0.64 1155 3.57 2.28 0.64 1221 3.45 2.21 0.64 1243
31 24 4.03 2.09 0.52 1199 3.78 1.97 0.52 1254 3.68 1.91 0.52 1281
31 26 4.24 1.69 0.40 1243 3.99 1.60 0.40 1297 3.87 1.55 0.40 1324
32 18 3.43 3.16 0.92 1068 3.15 2.90 0.92 1134 3.03 2.79 0.92 1155
32 20 3.61 2.88 0.80 1112 3.36 2.69 0.80 1166 3.24 2.59 0.80 1199
32 22 3.82 2.59 0.68 1155 3.57 2.43 0.68 1221 3.45 2.34 0.68 1243
32 24 4.03 2.25 0.56 1199 3.78 2.12 0.56 1254 3.68 2.06 0.56 1281
32 26 4.24 1.86 0.44 1243 3.99 1.76 0.44 1297 3.87 1.70 0.44 1324

INDOOR

DB(:)

INDOOR

WB(:)

OUTDOOR DB(:)

35 4340

Q SHC SHF INPUT Q SHC SHF INPUT Q SHC SHF INPUT

CAPACITY : 3.5(kW) SHF : 0.66 INPUT : 1090(W)

COOL operation (230V)

MSC-GA35VB : MUH-GA35VB

NOTE Q :Total capacity (kW) SHF :Sensible heat factor DB :Dry-bulb temperature

SHC :Sensible heat capacity (kW) INPUT :Total power input (W) WB :Wet-bulb temperature

18

PERFORMANCE DATA

OUTDOOR WB(:)

INDOOR

-10 -5 0 5 10 15 20

DB(:)

Q INPUT Q INPUT Q INPUT Q INPUT Q INPUT Q INPUT Q INPUT

CAPACITY : 2.5(kW)

INPUT : 690(W)

15
21
26

1.58

1.50

1.35

449
483
518

1.90

1.80

1.68

538
573
607

2.23

2.13

1.98

607
635
669

2.55

2.43

2.30

656
683
718

2.88

2.75

2.63

697
718
752

3.18

3.05

2.93

718
738
773

3.50

3.36

3.25

731
766
794

OUTDOOR WB(:)

INDOOR

-10 -5 0 5 10 15 20

DB(:)

Q INPUT Q INPUT Q INPUT Q INPUT Q INPUT Q INPUT Q INPUT

CAPACITY : 3.0(kW)

INPUT : 820(W)

15
21
26

1.89

1.80

1.62

533
574
615

2.28

2.16

2.01

640
681
722

2.67

2.55

2.37

722
754
795

3.06

2.91

2.76

779
812
853

3.45

3.30

3.15

828
853
894

3.81

3.66

3.51

853
877
918

4.20

4.04

3.90

869
910
943

OUTDOOR WB(:)

INDOOR

-10 -5 0 5 10 15 20

DB(:)

Q INPUT Q INPUT Q INPUT Q INPUT Q INPUT Q INPUT Q INPUT

CAPACITY : 3.7(kW)

INPUT : 1020(W)

15
21
26

2.33

2.22

2.00

663
714
765

2.81

2.66

2.48

796
847
898

3.29

3.15

2.92

898
938
989

3.77

3.59

3.40

969
1010
1061

4.26

4.07

3.89

1030
1061

1112

4.70

4.51

4.33

1061
1091
1142

5.18

4.98

4.81

1081
1132
1173

HEAT operation (230V)

MSC-GA20VB : MUH-GA20VB

MSC-GA25VB : MUH-GA25VB

MSC-GA35VB : MUH-GA35VB

NOTE Q:Total capacity (kW) INPUT:Total power input (W) DB:Dry-bulb temperature WB:Wet-bulb temperature

9

R.V. coil control

NOTE: The 4-way valve reverses for 5 seconds right before start-up of the compressor.

ACTUATOR CONTROL

Heating · · · · · ON
Cooling · · · · · OFF
Dry · · · · · · · · OFF

Compressor

R.V. coil

Outdoor fan

ON
OFF

ON
OFF

ON
OFF

(COOL / DRY)

5 seconds

(HEAT)

5 seconds

ON
OFF

ON
OFF

ON
OFF

19

Lead wiring

Housing point

10

Jumper wire

JRF

JRG

MODEL Change point

Defrost interval time changes from 40 minutes to 15 minutes.

Defrost start temperature changes from -3: to 0:.

MUH-GA20VB
MUH-GA25VB
MUH-GA35VB

SERVICE FUNCTIONS

MUH-GA20VB
MUH-GA25VB
MUH-GA35VB

10-1. COMPULSORY DEFROSTING MODE FOR SERVICE

By short circuit of the connector JPDS and JPSG on the outdoor deicer P.C. board, defrosting mode can be accom­plished regardless of the defrost interval restriction. (Refer to 11-5.)
Defrost thermistor RT61 must read below -3°C.

10-2. CHANGE IN DEFROST SETTING

<JRF> When the JRF wire of the deicer P.C. board is cut, the defrost interval time will be changed.
<JRG> When the JRG wire of the deicer P.C. board is cut, the defrost temperature will be changed.(Refer to 11-5.)

11

TROUBLESHOOTING

MUH-GA20VB
MUH-GA25VB
MUH-GA35VB

11-1. Cautions on troubleshooting

1. Before troubleshooting, check the following:

1) Check the power supply voltage.

2) Check the indoor/outdoor connecting wire for mis-wiring.

2. Take care the following during servicing.

1) Before servicing the air conditioner, be sure to turn off the main unit first with the remote controller, and then after con­firming the horizontal vane is closed, turn off the breaker and/or disconnect the power plug.

2) Be sure to turn OFF the power supply before removing the front panel, the cabinet, the top panel, and the electronic
control P.C. board.

3) When removing the electronic control P.C. board, hold the edge of the board with care NOT to apply stress on the
components.

4) When connecting or disconnecting the connectors, hold the housing of the connector. DO NOT pull the lead wires.

3. Troubleshooting procedure

1) First, check if the OPERATION INDICATOR lamp on the indoor unit is flashing on and off to indicate an abnormality.
To make sure, check how many times the abnormality indication is flashing on and off before starting service work.

2) If the electronic control P.C. board is supposed to be defective, check the copper foil pattern for disconnection and the
components for bursting and discoloration.

3) When troubleshooting, refer to 11-2. “Instruction of troubleshooting”.

20

11-2. Instruction of troubleshooting

Start

Indoor unit
operates.
Outdoor unit
doesn't
operate.

Indoor unit
doesn't receive
the signal from
remote controller.

Indoor unit
operates.
Outdoor unit
doesn't operate
normally.

OPERATION
INDICATOR
lamp on the
indoor unit is
flashing on
and off.

Outdoor unit
operates in
only T est Run
operation.

Outdoor unit
doesn't
operate
even in
Test Run
operation.

Indoor unit
operates,
when the
EMERGENCY
OPERATION
switch is
pressed.

Indoor unit
doesn't operate,
when the
EMERGENCY
OPERATION
switch is
pressed.

Check room
temperature
thermistor.
Refer to 11-5.
"Test point
diagram and
voltage".

Refer to 11-4.
A "Check of
outdoor unit".

Refer to
"Check of
remote
controller
and receiver
P.C. board".

Cause:
Indoor/Outdoor unit

• Mis-wiring or
trouble of serial
signal

2-time flash
Cause:
Indoor unit

• T roub le of
room temp­ erature/
indoor coil
thermistor

3-time flash
Cause:
Indoor unit

• T roub le of
indoor fan
motor

6-time flash
Cause:
Outdoor unit

• T roub le of
thermistor
in outdoor
unit

7-time flash
Cause:
Outdoor unit

• T roub le of
outdoor
control
system

Check room
temperature
thermistor
and indoor
coil thermis­tor.
Refer to 11-5.
"Test point
diagram and
voltage".

Refer to
"Check of
indoor fan
motor".

Refer to 11-4.
E"Check of
outdoor
thermistor".

Replace the
deicer
P.C. board.

Refer to 11-4. D
"How to check
mis-wiring and
serial signal
error (When
outdoor unit
doesn't work)".
W1

1. Check indoor /
outdoor
connecting wire.

2. Refer to
"Check of indoor
electronic control
P.C. board".

Outdoor unit
doesn't
stop even
if indoor unit
stops.

Unit doesn't
operate
normal
operation in
COOL or
HEAT mode.

Refer to 11-4.
B "Check of
outdoor unit".

Refer to 11-4.
C "Check of
R.V. coil".

W

1.<The case of the trouble of the serial signal>

When the power is turned off and then turned on again, the indication shows “the trouble of mis-wiring”.

W

"Test run operation"
means the

operation

within 30 minutes
after
EMERGENCY
OPERATION
switch is pressed.

Flash on and off at

0.5

-

second intervals

4-time flash
Cause:
Indoor unit

• T roub le of
indoor unit
control
system

Replace the
indoor
electronic
control
P.C. board.

Refer to indoor
unit service
manual.

W

W

MUH-GA20VB MUH-GA25VB MUH-GA35VB

21

Yes

Compressor
doesn't operate.

Yes

Yes

Is there 230V AC between 3 on the
compressor contactor (52C) and N
on the outdoor terminal block (TB1)?

Operate the unit in COOL or HEAT mode by pressing the EMERGENCY OPERATION switch.
3-minute time delay works.
Test run operation operates for 30 minutes.

Outdoor fan motor
doesn't operate.

No

Rectify the indoor and
outdoor connecting wire.

Rectify the connecting wire.

Check the compressor and compressor
capacitor, and rectify the connecting wire.

Start

Yes

Is there 230V AC between 4 on the
compressor contactor (52C) and
TAB20 on the deicer P.C. board?

Is there 230V AC between L–N
on the outdoor terminal block (TB1)?

Replace the
deicer P.C. board.

Replace the
deicer P.C.
board.

No

No

Yes

Yes

No

Check the outdoor fan motor
and rectify the connecting
wire.

Is there 230V AC between 4 on the
compressor contactor (52C) and
TAB 20 on the deicer P.C. board?

Replace the
deicer P.C. board.

No

Yes

Rectify the indoor and
outdoor connecting wire.

Rectify the connecting wire.

Is there 230V AC between L–N on
the outdoor terminal block (TB1)?

No

No

Is the switch SW2-2 on the
indoor electronic control
P.C. board set to MUH type?

No

Change the switch SW-2-2
on the indoor electronic control
P.C. board to MUH type.

Yes

+

–

Is there 5V DC between J205 –J101 on
the deicer P.C. board?

+

–

Is there 5V DC between J205 –J101 on
the deicer P.C. board?

P

R

C

S

RED

BLK

WHT

MAINAUX.

WHTRED

BLK

MAIN

AUX.

FUSE

11-3. Trouble criterion of main parts

MUH-GA20VB MUH-GA25VB MUH-GA35VB

Part name

Defrost
thermistor
(RT63)

Measure the resistance with a tester.
(Part temperature –10°C ~ 40°C)

Refer to 11-5. “Test point diagram and voltage”, “Outdoor deicer
P.C. board”, the chart of thermistor.

Check method and criterion

Figure

Compressor
(MC)
INNER

Measure the resistance between the terminals with a tester.
(Coil wiring temperature –10°C ~ 40°C)

PROTECTOR

MUH­GA20/GA25VB

150i 5°C OPEN

90i10°C CLOSE

MUH­GA20/GA25VB

E1

-

E2

-

C-R
C-S

MUH-GA20VB

3.41~4.18Ω

5.41~6.63Ω

E1

-

MUH-GA20VB

-

3.19~3.91Ω

4.76~5.83Ω

E2

160i5°C OPEN

90i10°C CLOSE

MUH-GA35VB

155i 5°C OPEN

90i10°C CLOSE

Measure the resistance between the terminals with a tester.
(Coil wiring temperature –10°C ~ 40°C)

Outdoor fan
motor
(MF)

INNER FUSE
145i 2°C

Color of

lead wire

WHT-BLK
BLK-RED

MUH-GA20VB

323 ~ 396 Ω
241 ~ 296 Ω

CUT OFF

11-4. Troubleshooting flow

Compressor and/or outdoor fan motor doesn’t operate.

Normal

MUH-GA25VB

2.99~3.67Ω

4.02~4.92Ω

Normal

E1

-

MUH-GA25VB

E2

-

3.19~3.91Ω

4.76~5.83Ω

MUH-GA25/GA35VB

189 ~ 233 Ω

270 ~ 332 Ω

MUH-GA35VB

2.46~3.01Ω

2.96~3.63Ω

P INNER PROTECTOR

AA

Check of outdoor unit

22

Compressor and/or outdoor fan motor doesn’t stop.

After 3 minutes, does the unit
operate in HEAT mode?

Ok

No

Is there 230V AC between
CN7211 – 2 on the deicer
P.C. board?

Replace the
deicer P.C. board.

Yes

Yes

Yes

No

Replace the R.V. coil.

Turn ON the power supply and operate
the indoor unit in COOL mode by pressing
the EMERGENCY OPERATION switch.

BB

Check of outdoor unit

Start

Turn OFF the power supply.
After 1 minute, turn ON
power supply again.

Is there 230V AC between 3 on the

Does compressor stop?

Yes

OK

No

compressor contactor (52C) and N on the
outdoor terminal block (TB1)?

Yes

Replace the
deicer P.C. board.

No

Rectify the connecting wire.

Does outdoor fan motor stop?

Yes

OK

No

Replace the
deicer P.C. board.

Unit operates COOL mode even if it is set to HEAT mode.

w First, measure the resistance of R.V. coil to confirm it is disconnected or is not short-circuit.

CC

Check of R.V. coil

Turn ON the power supply and operate
the indoor unit in HEAT mode by pressing
the EMERGENCY OPERATION switch.

After 3 minutes, does the unit
operate in COOL mode?

Yes

Is there 230V AC between
CN7211 – 2 on the deicer P.C.
board?

Yes

Replace the R.V. coil.

No

OK

No

Replace the
deicer P.C. board

Unit operates HEAT mode even if it is set to COOL mode.

w First, measure the resistance of R.V. coil to confirm it is disconnected or is not short-circuit.

CC

Check of R.V. coil

23

When OPERATION INDICATOR lamp flashes 0.5-second intervals.
Outdoor unit does not operate.

DD

How to check mis-wiring and serial signal error

w 1 Set the switch(SW2-2) on indoor electronic control P.C. board to

MU or MUX type, when the outdoor unit is MU or MUX type.

Start

Turn OFF the power supply(indoor/outdoor unit).

Is the outdoor unit "MUH" type?

•Turn ON the power supply(indoor/outdoor unit).

•Press once EMERGENCY OPERATION switch.

•3 min. later, check the self-check result

displayed on OPERATION INDICATOR
lamp on indoor unit.

Correct them.

1. Turn OFF the power supply(indoor/outdoor unit) and disconnect indoor and outdoor connecting wire on indoor side.

2. Short-circuit between indoor terminal block N and 3.

3. Turn ON the power supply

Yes

(indoor unit) and press EMERGENCY OPERATION switch once.

Is this mis-wiring, poor contact,
or disconnection of wire?

Yes

w 2

Serial signal error is indicated.
(0.5-sec. ON, 0.5-sec. OFF)

No

If the setting is MUH or MXZ type, the unit does not work.

w 2 Short circuit of JPG and JPS on the indoor electronic control
P.C. board enables self-check to be displayed in 3 seconds.

No

Set the switch(SW2-2) on the indoor electronic
control P.C. board to MU or MUX type.

Does the unit operate?

No

Refer to the
"Instruction of
troubleshooting."

Yes

w1

OK

Is there 20V DC between both ends of
R132 on indoor electronic control P.C.
board ?
( By tester, the stylus is between 0 ~ 20V. )

•Turn OFF the power supply(indoor unit).

•Connect indoor and outdoor connecting wire.

Turn ON the power supply(outdoor unit).

Is there 230V AC between outdoor terminal
block L-N (TB1)?

Is there 5V DC between J205 + –J101 - on the deicer P.C. board?

Turn ON the power supply(indoor unit).

During EMERGENCY OPERATION,
is there 10V DC between both ends
of R601?
(By tester, the stylus is between 5 ~10V)

Replace the deicer P.C. board.

Refer to indoor unit service manual.

Yes

Yes

Yes

Yes

No

Replace the indoor electronic
control P.C. board.

Check the outdoor power supply,

No

power supply cord and
connection.

No

Replace the deicer P.C. board.

Make the wiring between CN730

No

on the deicer P.C. board and
outdoor terminal block correct.

24

When OPERATION INDICATOR lamp flashes 6-time.
Thermistors in the outdoor unit are abnormal.

EE

Check of outdoor thermistor

Start

Turn OFF the
power supply.

Defrost thermistor (RT61)

Measure
resistance
between CN 661
1 and 2.

Is the resistance of
thermistor normal?

No

Replace the
thermistor.

Reconnect CN661.
Turn ON the power

Yes

supply and press
the EMERGENCY
OPERATION switch.

Replace the deicer P.C.

board.

No

Does the unit operate
10 minutes or more?

Yes

OK ❈

❈ Defective contact of the connector is considered.

25

11-5. Test point diagram and voltage

MUH-GA20VB
MUH-GA25VB
MUH-GA35VB
Outdoor deicer P.C. board

CN711
Outdoor fan motor
230V AC

}

CN721
R.V. coil
230V AC

}

5V DC
J205
J101

Power supply input

230V AC

}

NR61
Varistor

F61
Fuse

2A/250V

R601

+

5~10VDC

}

--

Defrost interval time
short pin
(JPDS, JPSG)
(Refer to 10-1.)

Jumper wire for
change in

}

}

CN661 1-2
Defrost thermistor RT61

+

--

defrost setting
(JRF,JRG)
(Refer to 10-2.)

12V DC
J204

+

J101

--

26

12

(1) Slide the sleeve and check if there is a locking lever or not.

(2) The terminal with this connector has the locking
mechanism.

1Slide the sleeve.
2Pull the terminal while

pushing the locking
lever.

1Hold the sleeve, and
pull out the terminal
slowly.

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.

<"Terminal with locking mechanism" Detaching points>

Connector

Sleeve

Locking lever

DISASSEMBLY INSTRUCTIONS

MUH-GA20VB MUH-GA25VB MUH-GA35VB

OUTDOOR UNIT

OPERATING PROCEDURE PHOTOS

1. Removing the cabinet

(1) Remove the screws of the top panel.
(2) Remove the screw of the service panel.
(3) Remove the screws of the cabinet.
(4) Remove the screws of the front panel and motor support.
(5) Remove the service panel, and remove the screw from

the insides.
(6) Remove the top panel.
(7) Remove the cabinet.

Photo 3

Screws of the
top panel

Screw of the
Service panel

Photo 1

Screw of the front panel and motor support

Screws of the cabinet

Photo 2

MUH-GA20VB

Screws of the
top panel

Screw of the cabinet

27

Screws of the
cabinet

OPERATING PROCEDURE PHOTOS

2. Removing the deicer P.C. board

(1) Remove the service panel and the cabinet.
(2) Disconnect all the connectors and the terminals on the

deicer P.C. board.

(3) Remove the deicer P.C. board.

3. Removing the propeller and the outdoor fan motor

(1) Remove the cabinet. (Refer to 1.)
(2) Remove the propeller nut.
(3) Remove the propeller.

NOTE : Loose the propeller in the rotating direction for

removal.

When attaching the propeller, align the mark on the
propeller and the motor shaft cut section.
Set the propeller in position by using the cut on the

shaft and the mark on the propeller.
(4) Disconnect the outdoor fan motor connector.
(5) Remove screws fixing the fan motor.
(6) Remove the outdoor fan motor.

Photo 4

Screw of the

relay panel

Photo 5

MUH-GA20VB

Screw of the
outdoor fan motor

Propeller

Deicer
P.C. board

Surge absorber

Relay panel

Terminal
cover

Terminal
block

Screws of
the relay
panel

28

Propeller

nut

Sound proof felt

R.V. coil

OPERATING PROCEDURE PHOTOS

4. Removing the compressor

(1) Remove the cabinet. (Refer to 1.)
(2) Remove the relay panel.
(3) Remove the soundproof felt.
(4) Remove the terminal cover on the compressor.
(5) Disconnect lead wires from the glass terminal of the com-

pressor.

(6) Recover gas from the refrigerant circuit.

NOTE : Recover gas from the pipes until the pressure gauge

shows 0 kg/cm
(7) Disconnect the welded part of the discharge pipe.
(8) Disconnect the welded part of the suction pipe.
(9) Remove nuts fixing the compressor.

)

(

Remove the compressor.

10

2

(0 MPa).

Photo 6

Glass
terminal

Compressor

Discharge pipe

Compressor nuts

4-Way valve

Suction
pipe

29

13

PARTS LIST (non-RoHS compliant)

MUH-GA20VB MUH-GA25VB MUH-GA35VB

13-1. OUTDOOR UNIT

STRUCTURAL PARTS, ELECTRICAL PARTS AND FUNCTIONAL PARTS

22

1

2

24

3

4

21

20

19

17 14

18

23

16

15

13

5

6 7

8

This figure shows MUH-GA20VB.

9

10 11

12

30

1

2

3
4

5
6
7

8

9

10
11
12

13
14
15

16

17

18
19

20
21

22
23
24

25
26

27
28
29
30
31
32
33

E02 904 630
E02 905 630
E02 906 630
E02 904 301
E02 905 301
E02 899 232
E02 903 232
E02 927 521
E02 665 501
E02 899 290
E02 905 290
E02 075 506
E02 742 900
E02 753 900
E02 754 900
E02 904 661
E02 904 662
E02 901 233
E02 927 233
E02 927 245
E02 838 704
E02 817 374
E02 836 374
E02 927 961
E02 931 961
E02 742 353
E02 665 353
E02 900 353
E02 895 383
E02 904 451
E02 905 451
E02 906 310
E02 899 523
E02 838 523
E02 927 297
E02 899 293
E02 899 515
E02 904 490
E02 906 490
E02 095 382
E02 820 385
E02 891 642
E02 408 936
E02 156 936
E02 024 936
E02 339 936
E02 282 936

OUTDOOR HEAT EXCHANGER
OUTDOOR HEAT EXCHANGER
OUTDOOR HEAT EXCHANGER
OUTDOOR FAN MOTOR
OUTDOOR FAN MOTOR
CABINET
CABINET
GRILLE
PROPELLER
BASE
BASE
COMPRESSOR RUBBER SET
COMPRESSOR
COMPRESSOR
COMPRESSOR
STOP VALVE (GAS)
STOP VALVE (LIQUID)
BACK PANEL
BACK PANEL
SERVICE PANEL
DRAIN SOCKET
TERMINAL BLOCK
TERMINAL BLOCK
4-WAY VALVE
4-WAY VALVE
COMPRESSOR CAPACITOR
COMPRESSOR CAPACITOR
COMPRESSOR CAPACITOR
SURGE ABSORBER
DEICER P.C. BOARD
DEICER P.C. BOARD
DEFROST THERMISTOR
CONDENSER NET
CONDENSER NET
TOP PANEL
SEPARATOR
MOTOR SUPPORT
R. V. COIL
R. V. COIL
FUSE
VARISTOR
CHECK VALVE
CAPILLARY TUBE
CAPILLARY TUBE
CAPILLARY TUBE
CAPILLARY TUBE
CAPILLARY TUBE

RA6V21­RA6V33-

3RUBBERS/SET
RN092VHSHT
RN104VHSHT
RN135VHSHT

[9.52
[6.35

3P
2P

20+ /440V AC
25+ /440V AC
30+ /440V AC

T2AL250V

[3.0O[1.4O700
[3.0O[1.4O500
[3.0O[1.4O1000
[3.0O[1.4O600
[3.0O[1.4O300

MF
MF

MC
MC
MC

TB1
TB2

C1
C1
C1

DSAR

RT61

21S4
21S4

F61

NR61

1

1

1
1
1

1
3

1

1
1

1
1
1
1
1
1

1

1

1
1

1
1
1
1
1

1
1
1

1
1

1

1

1

1
1
1

3
1

1
1
1

1
1
1
1
1

1

1
1

1
1

1
1
1
1

1
1
1
1
1

1

1

1
1
1

1
3

1
1
1

1
1
1
1
1

1

1
1

1
1

1
1
1
1

1
1
1
1

1

1

No.

Part No.

Remarks

Symbol

in Wiring

Diagram

Part name

Q'ty/unit

MUH-GA20VB

-

E1

MUH-GA25VB

-

E1

MUH-GA35VB

-

E1

PARTS LIST (non-RoHS compliant)

MUH-GA20VB MUH-GA25VB MUH-GA35VB

13-1. OUTDOOR UNIT

STRUCTURAL PARTS, ELECTRICAL PARTS AND FUNCTIONAL PARTS

Part numbers that are circled are not shown in the illustration.

31

14

RoHS PARTS LIST (RoHS compliant)

MUH-GA20VB MUH-GA25VB MUH-GA35VB
14-1. OUTDOOR UNIT

STRUCTURAL PARTS, ELECTRICAL PARTS AND FUNCTIONAL PARTS

22

1

2

24

3

4

21

20

19

17 14

18

23

16

15

13

5

6 7

8

This figure shows MUH-GA20VB.

9

10 11

12

32

RoHS PARTS LIST (RoHS compliant)

MUH-GA20VB MUH-GA25VB MUH-GA35VB
14-1.

OUTDOOR UNIT STRUCTURAL PARTS, ELECTRICAL PARTS AND FUNCTIONAL PARTS

Part numbers that are circled are not shown in the illustration.

No.

1

2

3
4

5

6

7

8

9

10

11
12

13
14
15

16

17

18

19

20

21

22
23

24

25
26

27
28

29

Part No.

RoHS

E12 904 630

G

E12 905 630

G

E12 906 630

G

E12 A86 630

G

E12 904 301

G

E12 905 301

G

E12 899 232

G

E12 903 232

G

E12 927 521

G

E12 665 501

G

E12 899 290

G

E12 905 290

G

E12 A89 290

G

E12 927 290

G

E12 075 506

G

E12 065 506

G

E12 742 900

G

E12 753 900

G

E12 754 900

G

E12 B14 900

G

E12 B17 900

G

E12 904 661

G

E12 904 662

G

E12 B16 662

G

E12 901 233

G

E12 927 233

G

E12 927 245

G

E12 838 704

G

E12 817 374

G

E12 836 374

G

E12 927 961

G

E12 931 961

G

E12 742 353

G

E12 665 353

G

E12 900 353

G

E12 895 383

G

E12 904 451

G

E12 905 451

G

E12 B16 451

G

E12 B17 451

G

E12 906 310

G

E12 899 523

G

E12 838 523

G

E12 929 523

G

E12 927 297

G

E12 899 293

G

E12 900 293

G

E12 899 515

G

E12 900 515

G

E12 904 490

G

E12 906 490

G

E12 095 382

G

E12 820 385

G

E12 891 642

G

E12 408 936

G

E12 156 936

G

E12 024 936

G

E12 339 936

G

E12 282 936

G

E12 B14 936

G

E12 B17 936

G

E12 139 936

G

E12 A86 936

G

E12 642 936

G

E12 735 936

G

Symbol

Part name

OUTDOOR HEAT EXCHANGER
OUTDOOR HEAT EXCHANGER
OUTDOOR HEAT EXCHANGER
OUTDOOR HEAT EXCHANGER
OUTDOOR FAN MOTOR
OUTDOOR FAN MOTOR
CABINET
CABINET
GRILLE
PROPELLER
BASE
BASE
BASE
BASE
COMPRESSOR RUBBER SET
COMPRESSOR RUBBER SET
COMPRESSOR
COMPRESSOR
COMPRESSOR
COMPRESSOR
COMPRESSOR
STOP VALVE (GAS)
STOP VALVE (LIQUID)
STOP VALVE (LIQUID)
BACK PANEL
BACK PANEL
SERVICE PANEL
DRAIN SOCKET
TERMINAL BLOCK
TERMINAL BLOCK
4-WAY VALVE
4-WAY VALVE
COMPRESSOR CAPACITOR
COMPRESSOR CAPACITOR
COMPRESSOR CAPACITOR
SURGE ABSORBER
DEICER P.C. BOARD
DEICER P.C. BOARD
DEICER P.C. BOARD
DEICER P.C. BOARD
DEFROST THERMISTOR
CONDENSER NET
CONDENSER NET
CONDENSER NET
TOP PANEL
SEPARATOR
SEPARATOR
MOTOR SUPPORT
MOTOR SUPPORT
R. V. COIL
R. V. COIL
FUSE
VARISTOR
CHECK VALVE
CAPILLARY TUBE
CAPILLARY TUBE
CAPILLARY TUBE
CAPILLARY TUBE
CAPILLARY TUBE
CAPILLARY TUBE
CAPILLARY TUBE
CAPILLARY TUBE
CAPILLARY TUBE
CAPILLARY TUBE
CAPILLARY TUBE

in Wiring

Diagram

MC
MC
MC
MC
MC

TB1
TB2

DSAR

RT61

21S4
21S4

F61

NR61

MF
MF

C1
C1
C1

MUH-GA20VB-

E1 E2

1

1

1

1
1
1

3

1

1
1

1

1
1
1
1
1

1

1
1

1
1

1
1

1

1

1
1
1
1
1

33

1

1

1

1
1

1

3

1

1

1
1

1
1
1
1
1

1

1

1

1
1

1
1

1

1

1
1
1

1
1

Q'ty/unit

MUH-GA25VB-

E1 E2

1

1

1
1
1

1

3

1

1
1

1
1
1
1
1
1

1

1

1

1

1

1
1

1

1

1
1
1

1
1

1

1

1
1
1

1

3

1
1

1

1
1
1
1
1
1

1

1

1
1

1

1
1

1

1

1
1
1

1
1

MUH-GA35VB-

E1

1

1

1
1
1

1

3

1

1
1

1
1
1
1
1

1

1
1

1

1

1

1
1

1

1
1
1
1

1

1

E3

1

1

1
1
1

1

3

1

1

1

1
1
1
1
1

1

1
1

1

1

1
1

1

1

1
1
1
1

1
1
2

Remarks

RA6V21­RA6V33-

3RUBBERS/SET
3RUBBERS/SET
RN092VHSHT
RN104VHSHT
RN135VHSHT
KN092VDMHC
KN104VTMHC

[9.52
[6.35
[6.35

3P
2P

20+ /440V AC
25+ /440V AC
30+ /440V AC

T2AL250V

[3.0O[1.4O700
[3.0O[1.4O500
[3.0O[1.4O1000
[3.0O[1.4O600
[3.0O[1.4O300
[3.0O[1.4O900
[3.0O[1.6O1500
[3.0O[1.6O750
[3.0O[1.4O350
[3.0O[1.4O400
[3.0O[1.8O600

34

35

HEAD OFFICE: TOKYO BLDG.,2-7-3, MARUNOUCHI, CHIYODA-KU, TOKYO100-8310, JAPAN

CC

Copyright 2005 MITSUBISHI ELECTRIC ENGINEERING CO.,LTD
Distributed in May 2007. No.OB387 REVISED EDITION-B 6
Distributed in May 2006. No.OB387 REVISED EDITION-A 6
Distributed in Feb. 2005. No.OB387 6
Made in Japan

New publication, effective May 2007
Specifications subject to change without notice.