SERVICE MANUAL
CONTENTS
1. TECHNICAL CHANGES ····································2
2. PART NAMES AND FUNCTIONS······················6
3. SPECIFICATION·················································6
4. NOISE CRITERIA CURVES·······························7
5. OUTLINES AND DIMENSIONS ·························8
6. WIRING DIAGRAM ············································9
7. REFRIGERANT SYSTEM DIAGRAM··············10
8. PERFORMANCE CURVES······························11
9. SERVICE FUNCTIONS ····································22
10. TROUBLESHOOTING······································22
11. DISASSEMBLY INSTRUCTIONS·····················29
12. PARTS LIST······················································32
Wireless type
Models
MUH-GA20VB -
MUH-GA25VB -
MUH-GA35VB -
E1
E1
E1
No. OB387
HFC
utilized
R410A
SPLIT-TYPE, HEAT PUMP AIR CONDITIONERS
MUH-GA20VB -
MUH-GA25VB -
MUH-GA35VB -
E1
E1
E1
Indication of
model name
NOTE:
•This manual describes technical data of outdoor units.
•As for indoor units MSC-GA20/GA25/GA35VB - , refer to the service manual OB385.
•As for indoor units MSC-CA20/CA25/CA35VB - , refer to the service manual OB393.
E1
E1
OB387-1.qxp 05.2.21 10:03 AM Page 1
TECHNICAL CHANGES
2
1
MUH-A07YV- ➔MUH-GA20VB-
1. Indication of capacity has been changed. (BTU base ➔ kw)
2. Dimension of outdoor unit has been changed. (780W
o540Ho255D ➔ 800Wo550Ho285D)
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. (780Wo540Ho255D ➔ 800Wo550Ho285D)
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)
MUH-A12YV- ➔MUH-GA35VB-
1. Indication of capacity has been changed. (BTU base ➔ kw)
2. Dimension of outdoor unit has been changed. (780Wo540Ho255D ➔ 800Wo550Ho285D)
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)
E1E1
E1E1
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3
Refrigeration
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 Destruction Parameter : based on CFC-11
w2 :Global Warmth Parameter : based on CO
2
INFORMATION FOR THE AIR CONDITIONER WITH R410A REFRIGERANT
• This room air conditioner adopts 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 R410A refrigerant 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.
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])
New Specification Current Specification
The incompatible refrigeration 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
refrigeration oil of the upper layer to flow back to the
compressor.
Since refrigerant and refrigerating oil are compatible each,
refrigeration oil goes back to the compressor through the
lower position oil back hole.
Compressor
Suction muffler
Oil back hole
Refrigeration oil
Refrigerant
Compressor
Suction muffler
Oil back hole
Refrigeration oil /Refrigerant
Compressor
OB387-1.qxp 05.2.21 10:03 AM Page 3
4
2.Refrigerant piping
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. Never use any pipe with a thickness less
than 0.8mm, as the pressure resistance is insufficient.
Wall
thickness
Outside diameter
Pipe
mm
For liquid
For gas
6.35
9.52
0.8 mm
0.8 mm
Heat resisting foam plastic
Specific gravity 0.045 Thickness 8 mm
Insulation material
-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
(:)
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])
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
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.
OB387-1.qxp 05.2.21 10:03 AM Page 4
5
R410A
Pipe diameter
mm
6.35
9.52
17
22
Dimension of flare nut
R22
17
22
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.Refrigeration 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 refrigeration 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.
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)
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6
PART NAMES AND FUNCTIONS
2
( )
Air inlet
Air outlet
Drain outlet
Piping
Drain hose
back : MUH-GA20VB
back and side : MUH-GA25VB
MUH-GA35VB
OUTDOOR UNIT
MUH-GA20VB -
MUH-GA25VB -
MUH-GA35VB -
E1
E1
E1
ACCESSORIES
MUH-GA20VB-
MUH-GA25VB-
MUH-GA35VB-
E1
E1
E1
Drain socket
1
<Outdoor unit: MUH type>
1
SPECIFICATION
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)
Thermistor RT61 (at 0:)
kW
R/h
K /h
A
A
W
A(kW)
%
A
A
A
W
"
"
mm
kg
dB
rpm
kg
cc
k"
MUH-GA20VB -
E1
Single phase
230V,50Hz
1800
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)
33.18
Cooling
2.3
0.9
3.00
680
99
2.76
3.22
Heating
2.5
—
2.86
655
100
2.62
3.62
MUH-GA25VB -
E1
Single phase
230V,50Hz
1902
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)
33.18
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
1902
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)
33.18
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
Compressor
Electrical
data
Fan
motor
Special
remarks
Capacity
Coefficient of performance (C.O.P)
Outdoor unit power supply
Function
Outdoor model
NOTE: Test conditions are based on ISO 5151.
Cooling : Indoor DB27°C WB19°C Heating : Indoor DB20°C
Outdoor DB35°C WB24°C Outdoor DB 7°C/WB 6°C
Indoor-Outdoor piping length : 5m
OB387-1.qxp 05.2.21 10:03 AM Page 6
7
NOISE CRITERIA CURVES
4
90
80
70
60
50
40
30
20
10
63 125 250 500 1000 2000 4000 8000
APPROXIMATE
TERESHOLD 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- E1
MUH-GA35VB- E1
COOLING
FUNCTION
49
HEATING
SPL(dB
(A)) LINE
OUTDOORUNIT
MICROPHONE
1m
90
80
70
60
50
40
30
20
10
63 125 250 500 1000 2000 4000 8000
APPROXIMATE
TERESHOLD 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- E1
COOLING
FUNCTION
47
HEATING
SPL(dB
(A)) LINE
OB387-1.qxp 05.2.21 10:03 AM Page 7
8
OUTLINES AND DIMENSIONS
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
Unit: mm
OUTDOOR UNIT
MUH-GA20VB - MUH-GA25VB - MUH-GA35VB -
E1E1E1
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9
WIRING DIAGRAM
6
MODELS WIRING DIAGRAM
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(2A)
COMPRESSOR(INNER PROTECTOR)
VARISTOR
DEFROST THERMISTOR
SOLID STATE RELAY
TRANS FORMER
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
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
MUH-GA20VB - MUH-GA25VB - MUH-GA35VB -
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10
REFRIGERANT SYSTEM DIAGRAM
7
OUTDOOR UNIT
(with heat insulator)
Refrigerant pipe [ 9.52
4-way valve
Defrost
thermistor
RT61
Muffler
Outdoor
heat
exchanger
Capillary tube
[3.0x[1.4x700 (MUH-GA20VB)
[3.0x[1.4x1000(MUH-GA25VB)
[3.0x[1.4x500 (MUH-GA35VB)
Capillary tube
[3.0x[1.4x500 (MUH-GA20VB)
[3.0x[1.4x600 (MUH-GA25VB)
[3.0x[1.4x300 (MUH-GA35VB)
Check valve
Strainer
#100
Refrigerant pipe [6.35
(with heat insulator)
Refrigerant flow in cooling
Refrigerant flow in heating
Unit:mm
Stop valve
(with service
port)
R.V. coil
heating ON
cooling OFF
Flared connection
Flared connection
Compressor
Stop valve
MUH-GA20VB - MUH-GA25VB - MUH-GA35VB -
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11
Piping size O.D : mm Length of connecting pipe : m
Model
Refrigerant piping
Max. length : m
A
20
25
Indoor unit
Gas 0.43
Liquid 0.5
Liquid
6.35
Gas
9.52
Outdoor unit
Gas 0
Liquid 0
MUH-GA20VB - E1
MUH-GA25VB - E1
MUH-GA35VB - E1
Indoor
unit
w Max. Height
difference 10m
Height difference should be within
10m regardless of which unit,
indoor or outdoor position is high.
Outdoor unit
Refrigerant Piping
Max.length
A
Model
Refrigerant piping length (one way)
7m
0
10m
60
15m
160
20m
260
MUH-GA20VB - E1
MUH-GA25VB - E1
MUH-GA35VB - E1
Calculation : Xg = 20g/m x (A-7)m
25m
360
Outdoor unit precharged
650
800
MAX. HEIGHT DIFFERENCE
ADDITIONAL REFRIGERANT CHARGE(R410A : g)
MAX. REFRIGERANT PIPING LENGTH
PERFORMANCE CURVES
8
The standard data contained in these specifications apply only to the operation of the air conditioner under normal conditions,
since operating conditions vary according to the areas where these units are installed. The following information has been pro-
vided 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
MUH-GA20VB - MUH-GA25VB - MUH-GA35VB -
E1E1E1
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12
MSC-GA20VB - E1
MUH-GA20VB - E1
MUH-GA35VB - E1
MSC-GA35VB - E1
MUH-GA25VB - E1
MSC-GA25VB - E1
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 - E1
MUH-GA20VB - E1
MUH-GA25VB - E1
MSC-GA25VB - E1
MUH-GA35VB - E1
MSC-GA35VB - E1
24.0
22.1
20.3
18.4
16.6
14.7
12.9
11.1
NOTE:The above curves are for the heating operation without any frost.
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
OUTDOOR UNIT
Wet-and dry-bulb
thermometers
Wet-and dry-bulb
thermometers
8-1.CAPACITY AND THE INPUT CURVES
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13
8-2.OUTDOOR LOW PRESSURE AND OUTDOOR UNIT CURRENT
COOL operation
① Both indoor and outdoor unit are under the same temperature/humidity condition.
➁ Air flow should be set at MAX.
Dry-bulb temperature
Relative humidity(%)
20
50
25
60
30 70
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] )
18 32
7
8
9
10
11
12
13
230V
15 20
50
25
60
30
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
MUH-GA20VB -
E1
MUH-GA20VB -
E1
Outdoor low pressure
Ambient temperature(˚C)
Ambient humidity(%)
Ambient temperature(˚C)
Ambient humidity(%)
Outdoor unit current (A)
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
MUH-GA25VB -
E1
Outdoor low pressure
Ambient temperature(˚C)
Ambient humidity(%)
15 20
50
25
60
30
70(%)
35(:)
1
2
4
3
18 32
230V
MUH-GA25VB -
E1
Ambient temperature(˚C)
Ambient humidity(%)
Outdoor unit current (A)
(kgf/F[Gauge])(MPa[Gauge])
(kgf/F[Gauge])(MPa[Gauge])
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
Outdoor low pressure
Ambient temperature(˚C)
Ambient humidity(%)
15 20
50
25
60
30
70(%)
35(:)
3
4
5
6
18 32
230V
Ambient temperature(˚C)
Ambient humidity(%)
Outdoor unit current (A)
(kgf/F[Gauge])(MPa[Gauge])
MUH-GA35VB -
E1
MUH-GA35VB -
E1
OB387-1.qxp 05.2.21 10:03 AM Page 13
14
HEAT operation
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
7
21
230V
5 10 15 20 25
3
4
5
6
(:)
7
21
230V
(:)
5 10 15 20 25
2
3
4
5
7
21
230V
5 10 15 20 25
2
3
4
5
(:)
Outdoor unit current (A) Outdoor unit current (A)
Outdoor unit current (A)
Ambient temperature(˚C)
Ambient temperature(˚C)
Ambient temperature(˚C)
MUH-GA20VB -
E1
MUH-GA25VB -
E1
MUH-GA35VB -
E1
OB387-1.qxp 05.2.21 10:03 AM Page 14
15
MSC-GA20VB - : MUH-GA20VB -
E1E1
PERFORMANCE DATA
COOL operation (230V)
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 INPUT
30
Q SHC SHF INPUT
CAPACITY : 2.3(kW) SHF : 0.74 INPUT : 715(W)
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
OB387-1.qxp 05.2.21 10:03 AM Page 15
16
MSC-GA20VB - : MUH-GA20VB -
E1E1
PERFORMANCE DATA
COOL operation (230V)
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)
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
OB387-1.qxp 05.2.21 10:03 AM Page 16
17
MSC-GA25VB - : MUH-GA25VB -
E1E1
PERFORMANCE DATA
COOL operation (230V)
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 INPUT
30
Q SHC SHF INPUT
CAPACITY : 2.65(kW) SHF : 0.70 INPUT : 820(W)
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
OB387-1.qxp 05.2.21 10:03 AM Page 17
18
MSC-GA25VB - : MUH-GA25VB -
E1E1
PERFORMANCE DATA
COOL operation (230V)
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)
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
OB387-1.qxp 05.2.21 10:03 AM Page 18
19
MSC-GA35VB - : MUH-GA35VB -
E1E1
PERFORMANCE DATA
COOL operation (230V)
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 INPUT
30
Q SHC SHF INPUT
CAPACITY : 3.5(kW) SHF : 0.66 INPUT : 1090(W)
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
OB387-1.qxp 05.2.21 10:03 AM Page 19
20
MSC-GA35VB - : MUH-GA35VB -
E1E1
PERFORMANCE DATA
COOL operation (230V)
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)
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
OB387-1.qxp 05.2.21 10:03 AM Page 20
21
MSC-GA20VB - : MUH-GA20VB -
E1E1
PERFORMANCE DATA
HEAT operation (230V)
MSC-GA25VB - : MUH-GA25VB -
E1E1
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
MSC-GA35VB - : MUH-GA35VB -
E1E1
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
NOTE Q:Total capacity (kW) INPUT:Total power input (W) DB:Dry-bulb temperature WB:Wet-bulb temperature
OB387-1.qxp 05.2.21 10:03 AM Page 21
22
TROUBLESHOOTING
10
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 10-2. “Instruction of troubleshooting”.
Lead wiring
Housing point
10-1. 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 con-
firming 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.
MUH-GA20VB -
MUH-GA25VB -
MUH-GA35VB -
E1
E1
E1
SERVICE FUNCTIONS
9
9-1. 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 accom-
plished regardless of the defrost interval restriction. (Refer to 10-5.)
Defrost thermistor RT61 must read below -3°C.
9-2. 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 10-5.)
Jumper wire
JRF
JRG
MODEL Change point
Defrost interval time changes from 40 minutes to 15 minutes.
Deforst start temperature changes from -3: to 0:.
MUH-GA20VB -
MUH-GA25VB -
MUH-GA35VB -
E1
E1
E1
MUH-GA20VB -
MUH-GA25VB -
MUH-GA35VB -
E1
E1
E1
OB387-1.qxp 05.2.21 10:03 AM Page 22
23
10-2. 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 Test 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 10-5
"Test point
diagram and
voltage".
Refer to 10-4.
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
• Trouble of
room temp-
erature/
indoor coil
thermistor
3-time flash
Cause:
Indoor unit
• Trouble of
indoor fan
motor
6-time flash
Cause:
Outdoor unit
• Trouble of
thermistor
in outdoor
unit
7-time flash
Cause:
Outdoor unit
• Trouble of
outdoor
control
system
Check room
temperature
thermistor
and indoor
coil thermis-
tor.
Refer to 10-5
"Test point
diagram and
voltage".
Refer to
"Check of
indoor fan
motor".
Refer to 10-4.
E"Check of
outdoor
thermistor".
Replace the
deicer
P.C. board.
Refer to 10-4. 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 10-4.
B "Check of
outdoor unit".
Refer to 10-4.
C "Check of
R.V. coil".
W1.<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”.
As for indoor unit
MSC type,
refer to service
manual OB385
or OB393.
Flash on and off at
0.5-second intervals
4-time flash
Cause:
Indoor unit
• Trouble of
indoor unit
control
system
Replace the
indoor
electronic
control
P.C. board.
MUH-GA20VB -
MUH-GA25VB -
MUH-GA35VB -
E1
E1
E1
OB387-1.qxp 05.2.21 10:03 AM Page 23
24
AA
Check of outdoor unit
Compressor and/or outdoor fan motor doesn’t operate.
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?
Compressor
(MC)
INNER
PROTECTOR
MUH-GA20/GA25VB
150i 5°C OPEN
90i10°C CLOSE
MUH-GA35VB
155i 5°C OPEN
90i10°C CLOSE
Part name
Check method and criterion
Measure the resistance between the terminals with a tester.
(Coil wiring temperature –10°C ~ 40°C)
Measure the resistance between the terminals with a tester.
(Coil wiring temperature –10°C ~ 40°C)
Figure
P
R
C
S
RED
BLK
WHT
MAINAUX.
WHTRED
BLK
MAIN
AUX.
FUSE
MUH-GA20VB - MUH-GA25VB - MUH-GA35VB -
E1E1E1
Defrost
thermistor
(RT63)
Measure the resistance with a tester.
(Part temperature –10°C ~ 40°C)
5kΩ ~ 60kΩ
Normal
Abnormal
Open or short-circuit
Normal
MUH-GA20VB
3.41~4.18Ω
5.41~6.63Ω
2.99~3.67Ω
2.46~3.01Ω
2.96~3.63Ω
C-R
C-S
Abnormal
Open or short-circuit
4.02~4.92Ω
MUH-GA25VB
MUH-GA35VB
Normal
MUH-GA20VB
323 ~ 396 Ω
241 ~ 296 Ω
189 ~ 233 Ω
270 ~ 332 Ω
WHT-BLK
BLK-RED
Abnormal
Open or short-circuit
MUH-GA25/GA35VB
P INNER PROTECTOR
Color of
lead wire
10-3. Trouble criterion of main parts
Outdoor fan
motor
(MF)
INNER FUSE
145i 2°C
CUT OFF
10-4. Troubleshooting flow
OB387-1.qxp 05.2.21 10:03 AM Page 24
25
BB
Check of outdoor unit
Does compressor stop?
No
Yes
Is there 230V AC between 3 on the
compressor contactor (52C) and N on the
outdoor terminal block (TB1)?
Replace the
deicer P.C. board.
Yes
OK
No
Does outdoor fan motor stop?
Replace the
deicer P.C. board.
Yes
OK
No
Rectify the connecting wire.
Start
Turn OFF the power supply.
After 1 minute, turn ON
power supply again.
Compressor and/or outdoor fan motor doesn’t stop.
CC
Check of R.V. coil
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.
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.
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
After 3 minutes, does the unit
operate in COOL mode?
OK
Yes
Yes
No
Replace the
deicer P.C. board
No
Replace the R.V. coil.
Turn ON the power supply and operate
the indoor unit in HEAT mode by pressing
the EMERGENCY OPERATION switch.
Is there 230V AC between
CN7211 – 2 on the deicer P.C.
board?
OB387-1.qxp 05.2.21 10:03 AM Page 25
26
DD
How to check mis-wiring and serial signal error
Serial signal error is indicated.
(0.5-sec. ON, 0.5-sec. OFF)
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(indoor unit) and press once EMERGENCY OPERATION switch.
During EMERGENCY OPERATION,
is there 10V DC between both ends
of R601?
(By tester, the stylus is between 5 ~10V)
•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.
w 2
Start
Turn OFF the power supply(indoor/outdoor unit).
No
No
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 ON indoor and outdoor connecting wire.
Is the outdoor unit "MUH" type?
Is this mis-wiring, poor contact,
or disconnection of wire?
Make them sure.
Replace the indoor electronic
control P.C. board.
Turn ON the power supply(outdoor unit).
Is there 230V AC between outdoor terminal
block L-N (TB1)?
No
Check the outdoor power supply,
power supply cord and
connection.
Yes
Turn ON the power supply(indoor unit).
No
Replace the deicer P.C. board.
Yes
No
Make the wiring between CN730
on the deicer P.C. board and
outdoor terminal block correct.
Replace the deicer P.C. board.
Yes
Yes
Yes
Set the switch(SW2-2) on the indoor electronic
control P.C. board to MU or MUX type.
w1
Yes
Does the unit operate?
OK
Yes
No
No
Refer to the
"Instruction of
troubleshooting."
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.
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.
If the setting is MUH or MXZ type, the unit does not work.
Is there 5V DC between J205 + –J101 - on the deicer P.C. board?
As for indoor unit MSC type, refer to service manual OB385 or OB393.
When OPERATION INDICATOR lamp flashes 0.5-second intervals or 1-time.
Outdoor unit does not operate.
OB387-1.qxp 05.2.21 10:03 AM Page 26
27
EE
Check of outdoor thermistor
Measure
resistance
between CN 661
1 and 2.
No
Yes
Replace the
thermistor.
Defrost thermistor (RT61)
Reconnect CN661.
Turn ON the power
supply and press
the EMERGENCY
OPERATION
switch.
Is the resistance of
thermistor normal?
No
Yes
Does the unit operate
10 minutes or more?
Replace the deicer P.C.
board.
OK ❈
❈ Defective contact of the connector is considered.
Turn OFF the
power supply.
Start
When OPERATION INDICATOR lamp flashes 6-time.
Thermistors in the outdoor unit are abnormal.
OB387-1.qxp 05.2.21 10:03 AM Page 27
28
MUH-GA20VB -
MUH-GA25VB -
MUH-GA35VB -
Outdoor deicer P.C. board
E1
E1
E1
CN711
Outdoor fan motor
230V AC
CN721
R.V. coil
230V AC
F61
Fuse
2A/250V
}
}
CN661 1-2
Defrost thermistor RT61
}
12V DC
J204
J101
R601
5~10VDC
}
--
+
5V DC
J205
J101
--
+
--
+
Power supply input
230V AC
}
NR61
Varistor
Jumper wire for
change in
defrost setting
(JRF,JRG)
(Refer to 9-2.)
}
Defrost interval time
short pin
(JPDS, JPSG)
(Refer to 9-1.)
10-5. Test point diagram and voltage
OB387-1.qxp 05.2.21 10:03 AM Page 28
29
DISASSEMBLY INSTRUCTIONS
11
MUH-GA20VB - MUH-GA25VB - MUH-GA35VB -
OUTDOOR UNIT
E1E1E1
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.
(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
Photo 1
Photo 3
Screws of the
top panel
Screw of the
Service panel
Screw of the cabinet
Screws of the
top panel
Screws of the
cabinet
Screws of the cabinet
Photo 2
Screw of the front panel and motor support
(W) This photo shows MUH-GA20VB.
OB387-2.qxp 05.2.21 10:03 AM Page 29
30
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 5
Propeller
Propeller
nut
Screw of the
outdoor fan motor
Terminal
cover
Screws of
the relay
panel
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.
Photo 4
Terminal
block
Surge absorber
Deicer
P.C. board
Relay panel
Screw of the
relay panel
Sound proof felt
R.V. coil
(W) This photo shows MUH-GA20VB.
OB387-2.qxp 05.2.21 10:03 AM Page 30
31
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
2
(0 MPa).
(7) Disconnect the welded part of the discharge pipe.
(8) Disconnect the welded part of the suction pipe.
(9) Remove nuts fixing the compressor.
(
10
)
Remove the compressor.
Photo 6
Compressor
Suction
pipe
4-Way valve
Discharge pipe
Compressor nuts
Glass
terminal
OB387-2.qxp 05.2.21 10:03 AM Page 31
32
PARTS LIST
12
22
3
5
2
21
1(W)
15
12-1. OUTDOOR UNIT STRUCTURAL PARTS
MUH-GA20VB - MUH-GA25VB - MUH-GA35VB -
E1E1E1
4
17 14
19
20
18
13
6 7
8
9
10 11
12
16
23
(W) This figure shows MUH-GA20VB.
24
OB387-2.qxp 05.2.21 10:03 AM Page 32
33
Part numbers that are circled are not shown in the illustration.
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
COMPRESSSOR 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
RA6V21-
RA6V33-
3RUBBERS/SET
RN092VHSHT
RN104VHSHT
RN135VHSHT
[9.52
[6.35
3P
2P
20+ /440V AC
25+ /440V AC
30+ /440V AC
250V 2A
[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
12-1. OUTDOOR UNIT STRUCTURAL PARTS
MUH-GA20VB - MUH-GA25VB - MUH-GA35VB -
E1E1E1
OB387-2.qxp 05.2.21 10:03 AM Page 33
34
OB387-2.qxp 05.2.21 10:03 AM Page 34
35
OB387-2.qxp 05.2.21 10:03 AM Page 35
CC
Copyright 2005 MITSUBISHI ELECTRIC ENGINEERING CO.,LTD
Distributed in Feb. 2005. No.OB387 6
Made in Japan
New publication, effective Feb. 2005
Specifications subject to change without notice.
HEAD OFFICE: MITSUBISHI DENKI BLDG.,2-2-3, MARUNOUCHI, CHIYODA-KU, TOKYO100-8310, JAPAN
OB387-2.qxp 05.2.21 10:03 AM Page 36
