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Page 1
Revision D:
• RoHS PARTS LIST has been changed.
SPLIT-TYPE, HEAT PUMP AIR CONDITIONERS
Please void OB455 REVISED EDITION-C.
OUTDOOR UNIT
HFC
SERVICE MANUAL
utilized
No. OB455
REVISED EDITION-D
R410A
Wireless type
Models
MUZ-GB50VA MUZ-GB50VA -
E1
E2
Indoor unit service manual
MSZ-GB·VA Series (OB454)
Refrigerant service manual
R410A REFRIGERANT (OBR01)
CONTENTS
1. TECHNICAL CHANGES ····································2
2. PART NAMES AND FUNCTIONS······················3
3. SPECIFICATION·················································3
4. NOISE CRITERIA CURVES ·······························4
5. OUTLINES AND DIMENSIONS ·························5
6. WIRING DIAGRAM ············································6
7. REFRIGERANT SYSTEM DIAGRAM ················7
8. PERFORMANCE CURVES ································9
9. ACTUATOR CONTROL····································14
10. TROUBLESHOOTING······································15
11. DISASSEMBLY INSTRUCTIONS·····················34
12. RoHS PARTS LIST···········································38
NOTE:
• This service manual describes technical data of the outdoor units.
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Page 2
Revision A:
• Compressor has been changed.
Previous
New
Model
SNB130FLDH
SNB130FLDH1
RoHS PARTS LIST number
E12 851 900
E12 939 900
Revision B:
• REFRIGERANT SYSTEM DIAGRAM has been changed.
• Oil separator has been added.
• Capillary tube has been added. ([1.8✕[0.6✕1000)
• MUZ-GB50VA- E2 has been added.
• Check of outdoor thermistors(10-6.B) has been corrected.
Revision C:
• RoHS PARTS LIST has been changed.
Revision D:
• RoHS PARTS LIST has been changed.
1
TECHNICAL CHANGES
MUZ-GA50VA - E1
➔ MUZ- GB50VA - E1
1. Refrigerant filling capacity has been changed.
2. Outdoor electronic control P.C. board has been changed.
MUZ-GB50VA - E1
➔ MUZ- GB50VA - E2
1. Compressor has been changed. (SNB130FLDH1 ➔ SNB130FLEH1)
2. Outdoor electronic control P.C. board has been changed.
2
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2
Page 3
PART NAMES AND FUNCTIONS
MUZ-GB50VA
ACCESSORIES
Air inlet
(back and side)
Piping
MUZ-GB50VA
Drain hose
1
Drain socket
1
2
Drain cap [33
2
Air outlet
Drain outlet
3
SPECIFICATION
MUZ-GB50VA
Outdoor model
Cooling
Function
Heating
Single phase
230V,50Hz
Power supply
Special
remarks
Fan
motor
Compressor
Electrical
data
Capacity
kW
Capacity Rated frequency(Min.-Max.)
r/h
Dehumidification
K /h
Air flow ✽1(High/Low)
A
Power outlet
A
Running current ✽1
W
Power input ✽1
%
Power factor ✽1
A
Starting current ✽1
A
Compressor motor current ✽1
A
Fan motor current ✽1
Coefficient of performance(C.O.P) ✽1
E1
Model
5.0(0.9-5.8)
2.5
2,940/1,650
20
7.23
1,610
Winding
resistance(at 20:)
6.91
7.11
0.32
3.03
3.41
SNB130FLDH or SNB130FLDH1
SNB130FLEH1
850
U-V 0.45 W-U 0.45
V-W 0.45
RC0J60-AA
BLK-WHT 15.2
WHT-RED 15.2
RED-BLK 15.2
840o850o330
53
W
"
"
mm
Dimensions WOHOD
kg
Weight
Sound level ✽1(High/Low) dB(A)
rpm
Fan speed (High/Low)
Fan speed regulator
Refrigerant filling
kg
capacity(R410A)
Refrigeration oil (Model)
7.43
1,660
97
7.46
E2
Output
Winding
resistance(at 20:)
Model
5.8(0.9-7.8)
—
2,940/2,210
52/51
800/480
55/53
800/620
2
1.50
NEO22
NOTE : Test conditions are based on ISO 5151.
Cooling : Indoor Dry-bulb temperature 27:Wet-bulb
Outdoor Dry-bulb temperature 35:Wet-bulb
Heating : Indoor Dry-bulb temperature 20:Wet-bulb
Outdoor Dry-bulb temperature 7: Wet-bulb
Refrigerant piping length (one way): 5m
✽1 Measured under rated operating frequency
3
temperature
temperature
temperature
temperature
19:
24:
15:
6:
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Page 4
Specifications and rating conditions of main electric parts
Model
MUZ-GB50VA
Item
Current transformer
(CT1,2)
ETQ19Z68AY
Current transformer
(CT61)
ETQ19Z53AY
(CB1,2,3)
Smoothing capacitor
560+ 450V
Fuse
(F64)
250V 2A
Fuse
(F801)
250V 3.15A
Fuse
(F911)
250V 1A
Expansion valve coil
(LEV)
CAM-MD12ME
Intelligent power module
(IPM)
PS21244-A
Intelligent power module
(HC930)
Power factor controller
PS21661-RZ
(L)
340µH 20A
(PFC)
PS51259-A
Reactor
Resistor
(R64A,B)
10" 10W
Resistor
(R937A,B)
1.1" 2W 2%
Resistor
(RS1~4)
0.04" 7W
Solenoid coil relay
(SSR61)
TLP3506
Terminal block
(TB1)
3P
Terminal block
(TB2)
3P
Relay
R.V. coil
4
(X64)
G4A
(21S4)
LD30013
NOISE CRITERIA CURVES
MUZ-GB50VA
FAN SPEED FUNCTION
SPL(dB(A))
COOLING
52
HEATING
55
LINE
High
OCTAVE BAND SOUND PRESSURE LEVEL, 0dB=20µPa
90
80
70
NC-70
60
NC-60
Test conditions
Cooling : Dry-bulb temperature 35:
Wet-bulb temperature (24:)
Heating : Dry-bulb temperature 7:
Wet-bulb temperature 6:
50
NC-50
40
NC-40
OUTDOOR UNIT
30
NC-30
20
10
63
125
1m
MICROPHONE
APPROXIMATE
THRESHOLD OF
HEARING FOR
CONTINUOUS
NOISE
NC-20
250
500
1000
2000
4000
8000
BAND CENTER FREQUENCIES, Hz
4
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5
Page 5
OUTLINES AND DIMENSIONS
MUZ-GB50VA
Unit: mm
REQUIRED SPACE
Open as a rule
500 mm or more if
the front and both
sides are open
515
299
40
100 mm or more
200 mm or more if
there are obstacles
to both sides
51
34
66
360
330
100 mm or more
500
840
121
80
Open as a rule
500 mm or more if the back,
both sides and top are open
350 mm or more
Service panel
155
90
35-
30-
430
850
Liquid refrigerant
pipe joint
Refrigerant pipe
(flared) [6.35
198
5
Gas refrigerant
pipe joint
Refrigerant pipe
(flared) [12.7
SYMBOL
CB1~3
CT1, 2
CT61
F64
F801
F911
HC930
IPM
L
LEV
PE
NOISE
FILTER
P.C.BOARD
GRN/YLW
N
S3
RED
BLU
WHT
NAME
SMOOTHING CAPACITOR
CURRENT TRANSFORMER
CURRENT TRANSFORMER
FUSE (T2AL 250V)
FUSE (T3.15AL 250V)
FUSE (T1AL 250V)
INTELLIGENT POWER MODULE
INTELLIGENT POWER MODULE
REACTOR
EXPANSION VALVE COIL
12-24V
S2
S1
TO INDOOR
UNIT
CONNECTING
230V~TB2
TAB2
CN61
3
1
BLU
BRN
WHT
BLU
NF
GRN
LDE1
SYMBOL
MC
MF
NF
NR64
PFC
R64A,B
R937A, B
RS1~4
RT61
RT62
CT61
F911
LDE2
CN912
F64
1 2
X64
TAB4
3
CN901
1 2 3
5
NR64
R64A R64B
SSR61
1
RT61 RT62
RT65
BLK
BLK
BLK
RT68
7 8
LEV
6
CN795
5 6 7
CN702
S
R
CN4
1 2
T801
1 2
CN701
RS2
RS1
1
LD1
3
RS4
RS3
R937B
R937A
LD2
CB2
CT1 U
V
U
CN932
RED
WHT
BLK
GRN
MF
POWER RT64
BOARD
BLK
WHT
MC
W
RED
V
GRY
PNK
ORN
BLU
YLW
LD9
IPM
CT2 W
NOTES: 1.About the indoor side electric wiring
NAME
SYMBOL
NAME
refer to the indoor unit electric wiring
COMPRESSOR
RT64 FIN TEMPERATURE THERMISTOR
diagram for servicing.
RT65 AMBIENT TEMPERATURE THERMISTOR
OUTDOOR FAN MOTOR
NOISE FILTER
2.Use copper conductors only (for field wiring).
OUTDOOR
HEAT
EXCHANGER
RT68
TEMPERATURE THERMISTOR
VARISTOR
3.Symbols below indicate.
SSR61 SOLENOID COIL RELAY
POWER FACTOR CONTROLLER
:Terminal block
:Connector
T801 TRANSFORMER
RESISTOR
TB1 TERMINAL BLOCK
RESISTOR
TB2 TERMINAL BLOCK
RESISTOR
X64 RELAY
DEFROST THERMISTOR
DISCHARGE TEMPERATURE THERMISTOR 21S4 R.V. COIL
CN661
1 2 3 4
CN663
1 2
21S4
1
4 YLW
L
RED
3
2
RED
ELECTRONIC 1 2 3
5
CONTROL
CN781
P.C.BOARD
BLK
BLK
BLK
BLK
BLU
BLU
CN902 CN903
2 1 2 1
BLK
YLW
BLK
BLK
BLK
PFC
2 1
CN5
7 6 5 4 3 2 1
CN2
BLK
BLK
L
GRN
3
1
CN601
5
6
F801
CB1
RED
CB3
WHT
CN801
TAB1
HC930
POWER SUPPLY
~/N 230V 50Hz
CIRCUIT
BREAKER
TB1
CN931
1 2 3 4 5
1 2 3
6
07.9.3 5:19 PM
CN3
1 2
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WIRING DIAGRAM
MUZ-GB50VA
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7
Page 7
REFRIGERANT SYSTEM DIAGRAM
MUZ-GB50VA- E1
Unit:mm
Muffler
4-way valve #100
Refrigerant pipe [12.7
(with heat insulator)
Stop valve
(with service port)
Flared connection
Outdoor
heat
exchanger
Discharge
temperature
thermistor
RT62
Defrost
thermistor
RT61
Ambient
temperature
thermistor
RT65
Compressor
Outdoor heat
exchanger
temperature
thermistor
RT68
Flared connection
LEV
Strainer
Receiver #100
Stop valve
Strainer
#100
R.V. coil
OFF
ON
Refrigerant flow in cooling
Refrigerant flow in heating
Capillary tube
[3.6✕[2.4✕50
Refrigerant pipe [6.35
(with heat insulator)
MUZ-GB50VA- E1
MUZ-GB50VA- E2
Refrigerant pipe [12.7
(with heat insulator)
Unit:mm
Capillary tube
[1.8✕[0.6✕1000
Oil separator
4-way valve
Stop valve
(with service port)
Strainer
#100
Defrost
thermistor
RT61
Discharge
temperature
thermistor
RT62
Flared connection
Compressor
Flared connection
Strainer
Receiver #100
Stop valve
Refrigerant pipe [6.35
(with heat insulator)
LEV
Strainer
#100
Capillary tube
[3.6✕[2.4✕50
Outdoor
heat
exchanger
Ambient
temperature
thermistor
RT65
Outdoor
heat
exchanger
temperature
thermistor
RT68
R.V. coil
heating ON
cooling OFF
Refrigerant flow in cooling
Refrigerant flow in heating
7
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Page 8
MAX. REFRIGERANT PIPING LENGTH and MAX. HEIGHT DIFFERENCE
Refrigerant piping : m
Model
MUZ-GB50VA
Piping size O.D : mm
Max. length
Max. Height difference
A
B
Gas
Liquid
30
15
12.7
6.35
Indoor
unit
Max. Height
difference
B
Max. length
A
Outdoor unit
ADDITIONAL REFRIGERANT CHARGE (R410A:g)
Refrigerant piping length (one way)
Model
Outdoor unit
precharged
7m
10m
15m
20m
25m
30m
MUZ-GB50VA
1,500
0
60
160
260
360
460
Calculation : Xg=20g/m ✕ (Refrigerant piping length (m)–7)
NOTE : Refrigerant piping exceeding 7m requires additional refrigerant charge according to the calculation.
8
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8
Page 9
PERFORMANCE CURVES
MUZ-GB50VA
The standard 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 provided to clarify the
operating characteristics of the air conditioner under the conditions indicated by the performance curve.
(1) GUARANTEED VOLTAGE
198 ~ 264V, 50Hz
(2) AIR FLOW
Air flow should be set at MAX.
(3) MAIN READINGS
(1) Indoor intake air wet-bulb temperature :
°C [WB]
(2) Indoor outlet air wet-bulb temperature :
°C [WB]
Cooling
(3) Outdoor intake air dry-bulb temperature :
°C [DB]
(4) Total input:
W
(5) Indoor intake air dry-bulb temperature :
°C [DB]
Heating
(6) Outdoor intake air wet-bulb temperature :
°C [WB]
(7) Total input :
W
Indoor air wet/dry-bulb temperature difference on the left side of the following chart 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.
}
}
How to measure the indoor air wet-bulb / dry-bulb temperature difference
1.
2.
3.
4.
5.
6.
7.
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.
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.
Check that the air filter is cleaned.
Open windows and doors of room.
Press the EMERGENCY OPERATION switch once (twice) to start the EMERGENCY COOL (HEAT) MODE.
When system stabilizes after more than 15 minutes, measure temperature and take an average temperature.
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
8.7
8.0
7.3
6.6
5.9
5.3
MSZ-GB50VA
MUZ-GB50VA
at Rated frequency
Indoor air Wet-bulb temperature
difference (:)
8-1. Capacity and input curves
Indoo
r inta
ke air
Wetbu
lb tem
lb tem
peratu
re (:
)
Outdoor intake air Dry-bulb temperature (:)
)
re (:
peratu
k
r inta
Indoo
et-bu
e air W
Outdoor intake air Dry-bulb temperature (:)
9
07.9.3 5:19 PM
Page 10
24.1
22.3
20.4
18.5
16.7
14.8
Ind
13.0
o
in
or
tak
ea
ir
yDr
bu
lb
p
tem
tu
era
re
)
(:
ture
pera
ake
int
oor
(:)
u
ry-b
air D
m
lb te
Ind
11.1
MSZ-GB50VA
MUZ-GB50VA
at Rated frequency
Indoor air Dry-bulb temperature
difference (:)
OB455D--1qxq
Outdoor intake air Wet-bulb temperature (:)
Outdoor intake air Wet-bulb temperature (:)
NOTE:The above broken lines are for the heating operation without any
frost and defrost operation.
8-2. Capacity and input correction by operational frequency of compressor
MUZ-GB50VA
Input correction factors
Capacity correction factors
1.0
0.5
0.0
0
50
100
150
The operational frequency of compressor
(Hz)
Correction of Cooling total input
1.5
1.0
0.5
0.0
0
50
100
150
(Hz)
Correction of Heating capacity
2.0
Input correction factors
1.5
Capacity correction factors
Correction of Cooling capacity
1.5
1.0
0.5
0.0
0
50
100
150
(Hz)
The operational frequency of compressor The operational frequency of compressor
Correction of Heating total input
1.5
1.0
0.5
0.0
0
50
100
(Hz)
The operational frequency of compressor
8-3. Test run operation (How to operate fixed-frequency operation)
1. Press EMERGENCY OPERATION switch to COOL or HEAT mode (COOL : Press once, HEAT : Press twice).
2. Test run operation starts and continues to operate for 30 minutes.
3. Compressor operates at rated frequency in COOL mode or 58Hz in HEAT mode.
4. Indoor fan operates at High speed.
5. After 30 minutes, test run operation finishes and EMERGENCY OPERATION starts (Operation frequency of compressor
varies).
6. To cancel test run operation (EMERGENCY OPERATION), press EMERGENCY OPERATION switch or any button on
remote controller.
10
150
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Page 11
8-4. OUTDOOR LOW PRESSURE AND OUTDOOR UNIT CURRENT
NOTE: The unit of pressure has been changed to MPa based on the international system of units (SI unit system).
f [Gauge])
The conversion factor is: 1(MPa [Gauge] = 10.2 (Kgf/f
COOL operation
1 Both indoor and outdoor unit are under the
same temperature/humidity condition.
2 Operation : TEST RUN OPERATION (refer to 8-3.)
Dry-bulb temperature(:)
Relative humidity(%)
20
50
25
60
30
70
MUZ-GB50VA
8
Outdoor unit current(A)
Outdoor low pressure
(kgf/F [Gauge])(MPa [Gauge])
1.0
10
9
0.9
8
0.8
7
0.7
6
0.6
5
0.5
15
25
30 32 35(˚C)
18 20
50
60
70
(%)
Ambient temperature(˚C)
Ambient humidity(%)
7
6
5
4
15
25
30 32 35(˚C)
18 20
50
60
70
(%)
Ambient temperature(˚C)
Ambient humidity(%)
HEAT operation
1 Condition :
Indoor
Outdoor
Dry bulb temperature (°C)
20.0
2
7
15
20.0
Wet bulb temperature (°C)
14.5
1
6
12
14.5
2 Operation : TEST RUN OPERATION (refer to 8-3.)
MUZ-GB50VA
Outdoor unit current (A)
8
7
6
5
4
0 2
5
10
15
20
25(˚C)
Ambient temperature(˚C)
11
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Page 12
PERFORMANCE DATA COOL operation at Rated frequency
MSZ-GB50VA : MUZ-GB50VA
CAPACITY:5.0(kW)
SHF:0.69
INPUT:1650(W)
21
Q SHC SHF INPUT
21
18
5.88 3.00 0.51 1320
21
20
6.13 2.39 0.39 1386
22
18
5.88 3.23 0.55 1320
22
20
6.13 2.63 0.43 1386
22
22
6.38 1.98 0.31 1436
23
18
5.88 3.47 0.59 1320
23
20
6.13 2.88 0.47 1386
23
22
6.38 2.23 0.35 1436
24
18
5.88 3.70 0.63 1320
24
20
6.13 3.12 0.51 1386
24
22
6.38 2.49 0.39 1436
24
24
6.70 1.81 0.27 1502
25
18
5.88 3.94 0.67 1320
25
20
6.13 3.37 0.55 1386
25
22
6.38 2.74 0.43 1436
25
24
6.70 2.08 0.31 1502
26
18
5.88 4.17 0.71 1320
26
20
6.13 3.61 0.59 1386
26
22
6.38 3.00 0.47 1436
26
24
6.70 2.35 0.35 1502
26
26
6.90 1.59 0.23 1584
27
18
5.88 4.41 0.75 1320
27
20
6.13 3.86 0.63 1386
27
22
6.38 3.25 0.51 1436
27
24
6.70 2.61 0.39 1502
27
26
6.90 1.86 0.27 1584
28
18
5.88 4.64 0.79 1320
28
20
6.13 4.10 0.67 1386
28
22
6.38 3.51 0.55 1436
28
24
6.70 2.88 0.43 1502
28
26
6.90 2.14 0.31 1584
29
18
5.88 4.88 0.83 1320
29
20
6.13 4.35 0.71 1386
29
22
6.38 3.76 0.59 1436
29
24
6.70 3.15 0.47 1502
29
26
6.90 2.42 0.35 1584
30
18
5.88 5.11 0.87 1320
30
20
6.13 4.59 0.75 1386
30
22
6.38 4.02 0.63 1436
30
24
6.70 3.42 0.51 1502
30
26
6.90 2.69 0.39 1584
31
18
5.88 5.35 0.91 1320
31
20
6.13 4.84 0.79 1386
31
22
6.38 4.27 0.67 1436
31
24
6.70 3.69 0.55 1502
31
26
6.90 2.97 0.43 1584
32
18
5.88 5.58 0.95 1320
32
20
6.13 5.08 0.83 1386
32
22
6.38 4.53 0.71 1436
32
24
6.70 3.95 0.59 1502
32
26
6.90 3.24 0.47 1584
NOTE
Q : Total capacity (kW)
SHC : Sensible heat capacity (kW)
INDOOR INDOOR
DB(:) WB(:)
OUTDOOR DB(:)
25
27
30
Q SHC SHF INPUT Q SHC SHF INPUT Q SHC SHF INPUT
5.63 2.87 0.51 1386 5.40 2.75 0.51 1452 5.20 2.65 0.51 1518
5.88 2.29 0.39 1469 5.70 2.22 0.39 1502 5.50 2.15 0.39 1568
5.63 3.09 0.55 1386 5.40 2.97 0.55 1452 5.20 2.86 0.55 1518
5.88 2.53 0.43 1469 5.70 2.45 0.43 1502 5.50 2.37 0.43 1568
6.15 1.91 0.31 1526 6.00 1.86 0.31 1568 5.75 1.78 0.31 1634
5.63 3.32 0.59 1386 5.40 3.19 0.59 1452 5.20 3.07 0.59 1518
5.88 2.76 0.47 1469 5.70 2.68 0.47 1502 5.50 2.59 0.47 1568
6.15 2.15 0.35 1526 6.00 2.10 0.35 1568 5.75 2.01 0.35 1634
5.63 3.54 0.63 1386 5.40 3.40 0.63 1452 5.20 3.28 0.63 1518
5.88 3.00 0.51 1469 5.70 2.91 0.51 1502 5.50 2.81 0.51 1568
6.15 2.40 0.39 1526 6.00 2.34 0.39 1568 5.75 2.24 0.39 1634
6.45 1.74 0.27 1584 6.30 1.70 0.27 1634 6.10 1.65 0.27 1716
5.63 3.77 0.67 1386 5.40 3.62 0.67 1452 5.20 3.48 0.67 1518
5.88 3.23 0.55 1469 5.70 3.14 0.55 1502 5.50 3.03 0.55 1568
6.15 2.64 0.43 1526 6.00 2.58 0.43 1568 5.75 2.47 0.43 1634
6.45 2.00 0.31 1584 6.30 1.95 0.31 1634 6.10 1.89 0.31 1716
5.63 3.99 0.71 1386 5.40 3.83 0.71 1452 5.20 3.69 0.71 1518
5.88 3.47 0.59 1469 5.70 3.36 0.59 1502 5.50 3.25 0.59 1568
6.15 2.89 0.47 1526 6.00 2.82 0.47 1568 5.75 2.70 0.47 1634
6.45 2.26 0.35 1584 6.30 2.21 0.35 1634 6.10 2.14 0.35 1716
6.70 1.54 0.23 1667 6.60 1.52 0.23 1716 6.40 1.47 0.23 1766
5.63 4.22 0.75 1386 5.40 4.05 0.75 1452 5.20 3.90 0.75 1518
5.88 3.70 0.63 1469 5.70 3.59 0.63 1502 5.50 3.47 0.63 1568
6.15 3.14 0.51 1526 6.00 3.06 0.51 1568 5.75 2.93 0.51 1634
6.45 2.52 0.39 1584 6.30 2.46 0.39 1634 6.10 2.38 0.39 1716
6.70 1.81 0.27 1667 6.60 1.78 0.27 1716 6.40 1.73 0.27 1766
5.63 4.44 0.79 1386 5.40 4.27 0.79 1452 5.20 4.11 0.79 1518
5.88 3.94 0.67 1469 5.70 3.82 0.67 1502 5.50 3.69 0.67 1568
6.15 3.38 0.55 1526 6.00 3.30 0.55 1568 5.75 3.16 0.55 1634
6.45 2.77 0.43 1584 6.30 2.71 0.43 1634 6.10 2.62 0.43 1716
6.70 2.08 0.31 1667 6.60 2.05 0.31 1716 6.40 1.98 0.31 1766
5.63 4.67 0.83 1386 5.40 4.48 0.83 1452 5.20 4.32 0.83 1518
5.88 4.17 0.71 1469 5.70 4.05 0.71 1502 5.50 3.91 0.71 1568
6.15 3.63 0.59 1526 6.00 3.54 0.59 1568 5.75 3.39 0.59 1634
6.45 3.03 0.47 1584 6.30 2.96 0.47 1634 6.10 2.87 0.47 1716
6.70 2.35 0.35 1667 6.60 2.31 0.35 1716 6.40 2.24 0.35 1766
5.63 4.89 0.87 1386 5.40 4.70 0.87 1452 5.20 4.52 0.87 1518
5.88 4.41 0.75 1469 5.70 4.28 0.75 1502 5.50 4.13 0.75 1568
6.15 3.87 0.63 1526 6.00 3.78 0.63 1568 5.75 3.62 0.63 1634
6.45 3.29 0.51 1584 6.30 3.21 0.51 1634 6.10 3.11 0.51 1716
6.70 2.61 0.39 1667 6.60 2.57 0.39 1716 6.40 2.50 0.39 1766
5.63 5.12 0.91 1386 5.40 4.91 0.91 1452 5.20 4.73 0.91 1518
5.88 4.64 0.79 1469 5.70 4.50 0.79 1502 5.50 4.35 0.79 1568
6.15 4.12 0.67 1526 6.00 4.02 0.67 1568 5.75 3.85 0.67 1634
6.45 3.55 0.55 1584 6.30 3.47 0.55 1634 6.10 3.36 0.55 1716
6.70 2.88 0.43 1667 6.60 2.84 0.43 1716 6.40 2.75 0.43 1766
5.63 5.34 0.95 1386 5.40 5.13 0.95 1452 5.20 4.94 0.95 1518
5.88 4.88 0.83 1469 5.70 4.73 0.83 1502 5.50 4.57 0.83 1568
6.15 4.37 0.71 1526 6.00 4.26 0.71 1568 5.75 4.08 0.71 1634
6.45 3.81 0.59 1584 6.30 3.72 0.59 1634 6.10 3.60 0.59 1716
6.70 3.15 0.47 1667 6.60 3.10 0.47 1716 6.40 3.01 0.47 1766
SHF : Sensible heat factor
DB : Dry-bulb temperature
INPUT : Total power input (W) WB : Wet-bulb temperature
12
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Page 13
PERFORMANCE DATA COOL operation at Rated frequency
MSZ-GB50VA : MUZ-GB50VA
CAPACITY:5.0(kW)
INDOOR INDOOR
DB(:) WB(:)
21
21
22
22
22
23
23
23
24
24
24
24
25
25
25
25
26
26
26
26
26
27
27
27
27
27
28
28
28
28
28
29
29
29
29
29
30
30
30
30
30
31
31
31
31
31
32
32
32
32
32
NOTE
18
20
18
20
22
18
20
22
18
20
22
24
18
20
22
24
18
20
22
24
26
18
20
22
24
26
18
20
22
24
26
18
20
22
24
26
18
20
22
24
26
18
20
22
24
26
18
20
22
24
26
Q
4.90
5.15
4.90
5.15
5.45
4.90
5.15
5.45
4.90
5.15
5.45
5.75
4.90
5.15
5.45
5.75
4.90
5.15
5.45
5.75
6.05
4.90
5.15
5.45
5.75
6.05
4.90
5.15
5.45
5.75
6.05
4.90
5.15
5.45
5.75
6.05
4.90
5.15
5.45
5.75
6.05
4.90
5.15
5.45
5.75
6.05
4.90
5.15
5.45
5.75
6.05
SHF:0.69
INPUT:1650(W)
OUTDOOR DB(:)
35
40
SHC SHF INPUT Q SHC SHF INPUT
2.50 0.51 1617 4.50 2.30 0.51 1716
2.01 0.39 1683 4.80 1.87 0.39 1766
2.70 0.55 1617 4.50 2.48 0.55 1716
2.21 0.43 1683 4.80 2.06 0.43 1766
1.69 0.31 1749 5.10 1.58 0.31 1848
2.89 0.59 1617 4.50 2.66 0.59 1716
2.42 0.47 1683 4.80 2.26 0.47 1766
1.91 0.35 1749 5.10 1.79 0.35 1848
3.09 0.63 1617 4.50 2.84 0.63 1716
2.63 0.51 1683 4.80 2.45 0.51 1766
2.13 0.39 1749 5.10 1.99 0.39 1848
1.55 0.27 1815 5.40 1.46 0.27 1898
3.28 0.67 1617 4.50 3.02 0.67 1716
2.83 0.55 1683 4.80 2.64 0.55 1766
2.34 0.43 1749 5.10 2.19 0.43 1848
1.78 0.31 1815 5.40 1.67 0.31 1898
3.48 0.71 1617 4.50 3.20 0.71 1716
3.04 0.59 1683 4.80 2.83 0.59 1766
2.56 0.47 1749 5.10 2.40 0.47 1848
2.01 0.35 1815 5.40 1.89 0.35 1898
1.39 0.23 1881 5.70 1.31 0.23 1964
3.68 0.75 1617 4.50 3.38 0.75 1716
3.24 0.63 1683 4.80 3.02 0.63 1766
2.78 0.51 1749 5.10 2.60 0.51 1848
2.24 0.39 1815 5.40 2.11 0.39 1898
1.63 0.27 1881 5.70 1.54 0.27 1964
3.87 0.79 1617 4.50 3.56 0.79 1716
3.45 0.67 1683 4.80 3.22 0.67 1766
3.00 0.55 1749 5.10 2.81 0.55 1848
2.47 0.43 1815 5.40 2.32 0.43 1898
1.88 0.31 1881 5.70 1.77 0.31 1964
4.07 0.83 1617 4.50 3.74 0.83 1716
3.66 0.71 1683 4.80 3.41 0.71 1766
3.22 0.59 1749 5.10 3.01 0.59 1848
2.70 0.47 1815 5.40 2.54 0.47 1898
2.12 0.35 1881 5.70 2.00 0.35 1964
4.26 0.87 1617 4.50 3.92 0.87 1716
3.86 0.75 1683 4.80 3.60 0.75 1766
3.43 0.63 1749 5.10 3.21 0.63 1848
2.93 0.51 1815 5.40 2.75 0.51 1898
2.36 0.39 1881 5.70 2.22 0.39 1964
4.46 0.91 1617 4.50 4.10 0.91 1716
4.07 0.79 1683 4.80 3.79 0.79 1766
3.65 0.67 1749 5.10 3.42 0.67 1848
3.16 0.55 1815 5.40 2.97 0.55 1898
2.60 0.43 1881 5.70 2.45 0.43 1964
4.66 0.95 1617 4.50 4.28 0.95 1716
4.27 0.83 1683 4.80 3.98 0.83 1766
3.87 0.71 1749 5.10 3.62 0.71 1848
3.39 0.59 1815 5.40 3.19 0.59 1898
2.84 0.47 1881 5.70 2.68 0.47 1964
Q : Total capacity (kW)
SHC : Sensible heat capacity (kW)
Q
4.30
4.60
4.30
4.60
4.90
4.30
4.60
4.90
4.30
4.60
4.90
5.25
4.30
4.60
4.90
5.25
4.30
4.60
4.90
5.25
5.50
4.30
4.60
4.90
5.25
5.50
4.30
4.60
4.90
5.25
5.50
4.30
4.60
4.90
5.25
5.50
4.30
4.60
4.90
5.25
5.50
4.30
4.60
4.90
5.25
5.50
4.30
4.60
4.90
5.25
5.50
SHF : Sensible heat factor
INPUT : Total power input (W)
13
SHC
2.19
1.79
2.37
1.98
1.52
2.54
2.16
1.72
2.71
2.35
1.91
1.42
2.88
2.53
2.11
1.31
3.05
2.71
2.30
1.21
1.27
3.23
2.90
2.50
1.10
1.49
3.40
3.08
2.70
1.00
1.71
3.57
3.27
2.89
0.89
1.93
3.74
3.45
3.09
0.79
2.15
3.91
3.63
3.28
0.68
2.37
4.09
3.82
3.48
0.58
2.59
43
SHF INPUT
0.51 1749
0.39 1815
0.55 1749
0.43 1815
0.31 1881
0.59 1749
0.47 1815
0.35 1881
0.63 1749
0.51 1815
0.39 1881
0.27 1947
0.67 1749
0.55 1815
0.43 1881
0.25 1947
0.71 1749
0.59 1815
0.47 1881
0.23 1947
0.23 2013
0.75 1749
0.63 1815
0.51 1881
0.21 1947
0.27 2013
0.79 1749
0.67 1815
0.55 1881
0.19 1947
0.31 2013
0.83 1749
0.71 1815
0.59 1881
0.17 1947
0.35 2013
0.87 1749
0.75 1815
0.63 1881
0.15 1947
0.39 2013
0.91 1749
0.79 1815
0.67 1881
0.13 1947
0.43 2013
0.95 1749
0.83 1815
0.71 1881
0.11 1947
0.47 2013
DB : Dry-bulb temperature
WB : Wet-bulb temperature
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Page 14
PERFORMANCE DATA HEAT operation at Rated frequency
MSZ-GB50VA : MUZ-GB50VA
CAPACITY:5.8(kW)
INDOOR
DB(:)
15
21
26
INPUT:1700(W)
OUTDOOR WB(:)
-10
-5
0
5
10
15
20
Q INPUT Q INPUT Q INPUT Q INPUT Q INPUT Q INPUT Q INPUT
3.65 1105 4.41 1326 5.16 1496 5.92 1615 6.67 1717 7.37 1768 8.12 1802
3.48 1190 4.18 1411 4.93 1564 5.63 1683 6.38 1768 7.08 1819 7.80 1887
3.13 1275 3.89 1496 4.58 1649 5.34 1768 6.09 1853 6.79 1904 7.54 1955
NOTE Q : Total capacity (kW) INPUT : Total power input (W) DB : Dry-bulb temperature WB : Wet-bulb temperature
9
ACTUATOR CONTROL
MUZ-GB50VA
9-1. Outdoor fan motor control
The fan motor turns ON/OFF, interlocking with the compressor.
[ON] The fan motor turns ON 5 seconds before the compressor starts up.
[OFF] The fan motor turns OFF 15 seconds after the compressor has stopped running.
5 seconds
15 seconds
ON
Compressor
OFF
ON
Outdoor fan
motor
OFF
9-2. R.V. coil control
Heating . . . . .
Cooling . . . . . .
Dry . . . . . . . . .
NOTE: The 4-way
. . . . . . . . . . . ON
. . . . . . . . . . . OFF
. . . . . . . . . . . OFF
valve reverses for 5 seconds right before start-up of the compressor.
<COOL>
<HEAT>
5 seconds
Compressor
ON
OFF
R.V.coil
ON
OFF
5 seconds
ON or OFF
ON or OFF
Outdoor fan ON
OFF
motor
14
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Page 15
9-3. Relation between main sensor and actuator
Sensor
Discharge temperature thermistor
Purpose
Compressor
Actuator
Outdoor
LEV
fan motor R.V. coil
Protection
Indoor pipe temperature thermistor Defrosting Protection
Defrost thermistor
Defrosting
Fin temperature thermistor
Protection
Outdoor heat exchanger temperature
Protection
Ambient temperature thermistor
Protection
10
TROUBLESHOOTING
MUZ-GB50VA
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 miswiring.
2. Take care of the following during servicing
1) Before servicing the air conditioner, be sure to turn OFF the main unit first with the remote controller, 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 electrical parts, be careful to the residual voltage of smoothing capacitor.
4) When removing the electronic control P.C. board, hold the edge of the board with care NOT to apply stress on the
components.
5) When connecting or disconnecting the connectors, hold the housing of the connector. DO NOT pull the lead wires.
Housing point
Lead wiring
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) Before servicing check that the connector and terminal are connected properly.
3) When the electronic control P.C. board seems to be defective, check the copper foil pattern for disconnection and the
components for bursting and discoloration.
4) When troubleshooting, refer to 10-2., 10-3. and 10-4.
15
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Page 16
10-2. Failure mode recall function
Outline of the function
This air conditioner can memorize the abnormal condition which has occurred once.
Even though LED indication listed on the troubleshooting check table (10-4.) disappears, the memorized failure details
can be recalled.
This mode is very useful when the unit needs to be repaired for the abnormality which doesn't recur.
1. Flow chart of failure mode recall function for the indoor/outdoor unit
Operational procedure
The cause of abnormality cannot be found because the abnormality doesn't recur.
Setting up the failure mode recall function
Turn ON the power supply.
<Preparation of the remote controller>
1 While pressing both OPERATION SELECT
button and TOO COOL button on the remote controller at the same time, press
RESET button.
2 First, release RESET button.
And release the other two buttons after all LCD except the set temperature in
operation display section of the remote controller is displayed after 3 seconds.
Press OPERATE/STOP(ON/OFF) button of the remote controller (the set temperature
is displayed) with the remote controller headed towards the indoor unit. w1
W 1. Regardless of normal or abnormal condition, a short
beep is emitted once the signal is received.
Does the left lamp of OPERATION INDICATOR
lamp on the indoor unit blink at the interval of 0.5
seconds?
Blinks: Either indoor or outdoor unit is abnormal.
Beep is emitted at the same timing
as the blinking of the left lamp of
OPERATION INDICATOR lamp. W2
Yes
Judgment of indoor/outdoor abnormality
(Blinks)
Before blinking, does the left lamp of
OPERATION INDICATOR lamp stay ON for 3
seconds?
Stays ON for 3 seconds (without beep):
The outdoor unit is abnormal.
No
(OFF)
Indoor unit is normal.
But the outdoor unit might be abnormal because there are some
abnormalities that can't be recalled with this way.
Confirm if outdoor unit is abnormal according to the detailed outdoor
unit failure mode recall function.(Refer to 10-2.2)
Yes
No
The indoor unit is abnormal.
Check the blinking pattern, and confirm the abnormal point with the indoor unit
failure mode table (Refer to indoor unit service manual.)
Make sure to check at least two consecutive blinking cycles. W2
The outdoor unit is abnormal.
Check the blinking pattern, and confirm the abnormal point with the
outdoor unit failure mode table (Refer to 10-2.3).
Make sure to check at least two consecutive blinking cycles. W3
Releasing the failure mode recall function
Release the failure mode recall function by the following procedures.
Turn OFF the power supply and turn it ON again.
Press RESET button of the remote controller.
Repair the defective parts.
Deleting the memorized abnormal condition
1After repairing the unit, recall the failure mode again according to
"Setting up the failure mode recall function" mentioned above.
2Press OPERATE/STOP(ON/OFF) button of the remote controller (the set temperature is displayed)
with the remote controller headed towards the indoor unit.
3Press EMERGENCY OPERATION switch so that the memorized abnormal condition is deleted.
4Release the failure mode recall function according to "Releasing the failure mode recall function"
mentioned above.
Note1.Make sure to release the failure mode recall function once it's set up, otherwise the unit cannot operate properly.
2.If the abnormal condition is not deleted from the memory, the last abnormal condition is kept memorized.
W2. Blinking pattern when the indoor unit is abnormal:
Blinking at 0.52.5-second OFF second interval
Blinking at 0.52.5-second OFF second interval
ON
OFF
Beeps
Repeated cycle
Beeps
Repeated cycle
W3.Blinking pattern when the outdoor unit is abnormal:
Blinking at 0.52.5-second OFF
3-second ON
second interval
2.5-second OFF
Beeps
Repeated cycle
3-second ON
Blinking at 0.5second interval
ON
OFF
No beep
Repeated cycle
Beeps
No beep
Repeated cycle
16
Beeps
Repeated cycle
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Page 17
2. Flow chart of the detailed outdoor unit failure mode recall function
Operational procedure
The outdoor unit might be abnormal.
Confirm if outdoor unit is abnormal according to the following procedures.
Confirm that the remote controller is in the failure mode recall
function.
With the remote controller headed towards the indoor unit, press TOO COOL or TOO
WARM button to adjust the set temperature to 25:. W1
Does left lamp of OPERATION INDICATOR lamp
on the indoor unit blink at the interval of 0.5 seconds?
Blinks: The outdoor unit is abnormal.
Beep is emitted at the same
timing as the blinking of the left lamp of
OPERATION INDICATOR lamp. W2
W1. Regardless of normal or abnormal condition, 2 short
beeps are emitted as the signal is received.
No
(OFF)
Yes
(Blinks)
The outdoor unit is abnormal.
Check the blinking pattern, and confirm the abnormal point with the
outdoor unit failure mode table (Refer to 10-2.3.).
Make sure to check at least two consecutive blinking cycles. W2
The outdoor unit is normal.
Releasing the failure mode recall function
Release the failure mode recall function by the following procedures.
Turn OFF the power supply and turn it ON again.
Press RESET button of the remote controller.
Release the failure mode recall function according
to the left mentioned procedure.
Repair the defective parts.
Deleting the memorized abnormal condition
1After repairing the unit, recall the failure mode again according to
"Setting up the failure mode recall function" mentioned above.
2Press OPERATE/STOP(ON/OFF) button of the remote controller (the set temperature is displayed)
with the remote controller headed towards the indoor unit.
3Press EMERGENCY OPERATION switch so that the memorized abnormal condition is deleted.
4Release the failure mode recall function according to "Releasing the failure mode recall function"
mentioned above.
Note1. Make sure to release the failure mode recall function once it's set up, otherwise the unit cannot operate properly.
2. If the abnormal condition is not deleted from the memory, the last abnormal condition is kept memorized.
W2.Blinking pattern when outdoor unit is abnormal:
2.5-second OFF
3-second ON
Blinking at 0.5second interval
2.5-second OFF
3-second ON
Blinking at 0.5second interval
ON
OFF
No beep
Repeated cycle
No beep
Repeated cycle
Beeps
17
Beeps
Repeated cycle
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Page 18
3. Outdoor unit failure mode table
MUZ-GB50VA
The left lamp of
OPERATION INDICATOR
lamp (Indoor unit)
Abnormal point
(Failure mode / protection)
LED indication
Correspondence
Condition
(Outdoor P.C. board)
LED 1 LED 2
Lighting Lighting Overcurrent protection stop is
• Check the connection
continuously performed 3 times within
of the compressor
1 minute after the compressor gets
connecting wire.
started, or converter protection stop or • Refer to 10-6.A
bus-bar voltage protection stop is
"How to check
continuously performed 3 times within
inverter / compressor".
3 minutes after start-up.
• Check the stop valve.
OFF
2-time flash
None (Normal)
Outdoor power system
3-time flash
Discharge temperature
thermistor
Lighting Once
Defrost thermistor
Ambient temperature thermistor
Fin temperature thermistor
P.C. board temperature
thermistor
Lighting
Lighting
Lighting
Lighting
Outdoor heat exchanger
temperature thermistor
Lighting 9 times
Thermistor shorts or opens during
compressor running.
Once
Twice
3 times
4 times
• Refer to 10-6.B "Check
of outdoor thermistors".
• Replace the outdoor
electronic control
P.C. board.
• Refer to 10-6.B "Check
of outdoor thermistors".
4-time flash
Overcurrent
5-time flash
Discharge temperature
•Check refrigerant circuit
Lighting Lighting Discharge temperature exceeds
116°C during operation.
and refrigerant amount.
Compressor can restart if discharge
• Refer to 10-6.G "Check
temperature thermistor reads 100: or
of LEV".
less 3 minutes later.
6-time flash
High pressure
Lighting Lighting Tthe outdoor heat exchanger
temperature exceeds 70: during
cooling or the indoor gas pipe
temperature exceeds 70: during
heating.
•Check refrigerant circuit
and refrigerant amount.
• Check the stop valve.
7-time flash
Fin temperature
3 times
Goes
out
The fin temperature exceeds 87:
during operation.
P.C. board temperature
4 times
Goes
out
The P.C. board temperature exceeds
70: during operation.
• Check around outdoor
unit.
• Check outdoor unit air
passage.
• Refer to 10-6.D "Check
of outdoor fan motor".
8-time flash
Outdoor fan motor
Lighting Lighting Failure occurs continuously 3 times
within 30 seconds after the fan gets
started.
• Refer to 10-6.D "Check
of outdoor fan motor".
9-time flash
Nonvolatile memory data
Lighting 5 times Nonvolatile memory data cannot be
read properly.
10-time flash
Discharge temperature
Lighting Lighting The frequency of the compressor is
kept 80Hz or more and the discharge
temperature is kept under 39:
for more than 20 minutes.
• Replace the outdoor
electronic control
P.C. board.
•Check refrigerant circuit
and refrigerant amount.
• Refer to 10-6.G "Check
of LEV".
Once
Goes
out
28A current flows into intelligent
power module.
• Reconnect compressor
connector.
• Refer to 10-6.A "How to
check inverter/
compressor."
• Check the stop valve.
NOTE : Blinking patterns of this mode differ from the ones of Troubleshooting check table (10-4.).
18
Indoor/outdoor
unit failure mode
recall function
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07.9.3 5:20 PM
The left lamp of
OPERATION INDICATOR
lamp (Indoor unit)
11-time flash
Page 19
Abnormal point
(Failure mode / protection)
LED indication
(Outdoor P.C. board)
LED 1 LED 2
Condition
Correspondence
Communication error
between P.C. boards
Lighting 6 times
Communication error occurs between
• Check the connecting
the electronic control P.C. board and
wire between outdoor
power board for more than 10 seconds.
electronic control
P.C. board and power
The communication between boards
board.
protection stop is continuously
performed twice.
Current sensor
Lighting 7 times
Zero cross detecting circuit
5 times
A short or open circuit is detected
in the current sensor during
compressor operating.
Current sensor protection stop is
continuously performed twice.
Zero cross signal cannot be detected
while the compressor is operating.
Goes
out
The protection stop of the zero
cross detecting circuit is continuously
performed 10 times.
Converter
5 times Goes
out
A failure is detected in the operation
of the converter during operation.
Bus-bar voltage
(1)
5 times
Goes
out
The bus-bar voltage exceeds 400V
or falls to 200V or below during
compressor operating.
6 times Goes
Bus-bar voltage
out
(2)
wEven if this protection stop is
performed continuously 3 times,
it does not mean the abnormality
in outdoor power system.
The bus-bar voltage exceeds 400V
or falls to 50V or below during
compressor operating.
• Replace the power
board.
• Check the connecting
wire among electronic
control P.C. board,
noise filter P.C. board
and power board.
• Replace the power
board.
NOTE : Blinking patterns of this mode differ from the ones of Troubleshooting check table (10-4.).
19
Indoor/outdoor
unit failure mode
recall function
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Page 20
10-3. Instruction of troubleshooting
Start
Indoor unit
operates.
Outdoor unit
doesn't
operate.
Indoor unit operates.
Outdoor unit doesn't
operate normally.
OPERATION
INDICATOR
lamp on the indoor
unit is flashing on
and off.
Indoor unit
doesn't receive
the signal from
remote controller.
If blinking of OPERATION
INDICATOR lamp cannot
be checked, it can be checked
with failure mode recall function.
Outdoor unit
operates only
in Test Run
operation.
(Refer to 8-3.)
w
Outdoor unit
doesn't
operate
even in
Test Run
operation.
(Refer to 8-3.)
w
Unit doesn't
operate
normal
operation in
COOL or
HEAT mode.
Indoor unit
operates, when
EMERGENCY
OPERATION
switch is pressed.
Indoor unit
doesn't operate,
when
EMERGENCY
OPERATION
switch is pressed.
Check room
temperature
thermistor.
Refer to
"Test point
diagram and
voltage".
Refer to 10-6.A
"How to check
inverter/
compressor".
Refer to 10-6.C
"Check of
R.V. coil".
Refer to
"Check of
remote controller
and receiver
P.C. board".
1. Check indoor / outdoor
connecting wire.
(Check if the power
is supplied to the
indoor unit.)
2. Refer to
"Check of indoor
electronic control
P.C. board and indoor
fan motor".
All lamps
Flash on and off
at 0.5-second
intervals
Cause:
Indoor unit
• The horizontal
vane is not
installed
correctly.
Left lamp
Flash on and
off at
0.5-second
intervals
Cause:
Indoor/
Outdoor unit
• Miswiring or
trouble of
serial signal.
Left lamp
2-time flash
Cause:
Indoor unit
• Trouble of
room temperature/
indoor coil
thermistor
Refer to
"Check of
installation of
the horizontal
vane".
Refer to 10-6.H
"How to check
miswiring
and serial
signal error".
Check room
temperature
thermistor
and indoor
coil thermistor.
Refer to "Test
point diagram
and voltage".
Left lamp
3-time flash
Cause:
Indoor unit
• Trouble of
indoor fan
motor
Refer to
"Check of
indoor fan
motor".
Left lamp
4-time flash
Cause:
Indoor unit
• Trouble of
indoor unit
control
system
Replace the
indoor
electronic
control
P.C. board.
20
Left lamp
5-time flash
Cause:
Outdoor unit
• Outdoor
power
system
abnormality
Refer to 10-6.A
"How to check
inverter/
compressor".
w "Test Run operation" means
the operation within 30 minutes
after EMERGENCY OPERATION
switch is pressed.
Left lamp
6-time flash
Cause:
Outdoor unit
• Trouble of
thermistor
in outdoor
unit
Refer to 10-6.B
"Check of
outdoor
thermistors".
Refer to indoor unit
service manual.
Left lamp
7-time flash
Cause:
Outdoor unit
• Trouble of
outdoor
control
system
Left lamp
14-time flash
Cause:
Outdoor unit
• Other
abnormality
Replace
inverter P.C.
board or outdoor control
electronic
control P.C.
board.
Check 10-2.2.
"Flow chart of
the detailed
outdoor unit
failure mode
recall function."
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Page 21
10-4. Troubleshooting check table
MUZ-GB50VA
No. Symptom
Indication
LED1(Red) LED2(Yellow)
Condition
Abnormal point / Condition
Outdoor unit
does not
operate.
1
Lightning
Twice
Outdoor power system
2
Lightning
3 times
Discharge temperature
thermistor
3
Lightning
4 times
Overcurrent protection stop is continuously performed 3 times within
1 minute after the compressor gets started, or when converter protection
stop or bus-bar voltage protection stop is continuously performed 3 times
within 3 minutes after start-up.
4
Lightning
5 times
• Check the connection of the compressor connecting
wire.
• Refer to 10-6.A "How to check inverter/compressor".
• Check the stop valve.
A short circuit is detected in the thermistor during operation, or an open
• Refer to 10-6.B "Check of outdoor thirmistors".
circuit is detected in the thermistor after 10 minutes of compressor start-up.
Fin temperature thermistor
P.C board temperature
thermistor
Ambient temperature
thermistor
Correspondence
• Refer to 10-6.B "Check of outdoor thirmistors".
A short or open circuit is detected in the thermistor during operation.
• Replace the outdoor electronic control P.C. board.
A short or open circuit is detected in the thermistor during operation.
Outdoor heat exchanger
temperature thermistor
A short circuit is detected in the thermistor during operation, or an open
circuit is detected in the thermistor after 5 minutes (in cooling) and
10 minutes (in heating) of compressor start-up.
Defrost thermistor
A short circuit is detected in the thermistor during operation, or an open
circuit is detected in the thermistor after 5 minutes of compressor start-up.
• Refer to 10-6.B "Check of outdoor thirmistors".
5
Lightning
6 times
Serial signal
The communication fails between the indoor and outdoor unit for 3 minutes.
• Refer to 10-6.H "How to check miswiring and serial signal
error".
6
Lightning
7 times
Nonvolatile memory data
The nonvolatile memory data cannot be read properly.
• Replace the outdoor electronic control P.C. board.
7
Lightning
8 times
Current sensor
Current sensor protection stop is continuously performed twice.
• Replace the power board.
8
Lightning
11 times
Communication error
between P.C. boards
The communication protection stop between boards is continuously
performed twice.
9
Lightning
12 times
Zero cross detecting circuit
The protection stop of the zero cross detecting circuit is continuously
performed 10 times.
• Check the connecting wire between outdoor electronic control
P.C. board and power board.
• Check the connecting wire among outdoor electronic control
P.C. board, noise filter P.C. board and power board.
IPM protection
Overcurrent is detected after 30 minutes of compressor start-up.
Lock protection
Overcurrent is detected within 30 minutes of compressor start-up.
Discharge temperature
protection
Discharge temperature exceeds 116:during operation and compressor
stops. Compressor can restart if discharge temperature thermistor reads
100: or less 3 minutes later.
• Check the amount of gas and refrigerant circuit.
• Refer to 10-6.G "Check of LEV".
Fin temperature protection
The fin temperature exceeds 87: during operation.
•Check refrigerant circuit and refrigerant amount.
•Refer to 10-6.D "Check of outdoor fan motor".
'Outdoor unit
stops and
restarts 3
Twice
10 minutes
later' is
repeated.
11
12
Goes out
3 times
Goes out
4 times
Goes out
13
5 times
Goes out
14
8 times
Goes out
15
9 times
Goes out
P.C. board temperature
protection
High-pressure protection
Converter protection
Bus-bar voltage protection (1)
Bus-bar voltage protection (2)
16
13 times
Goes out
17
Lighting
8 times
18
Lighting
11 times
19
Lighting
12 times
Outdoor fan motor
Current sensor protection
Communication between P.C.
boards protection
Zero cross detecting circuit
protection
The P.C. board temperature exceeds 70: during operation.
The outdoor heat exchanger temperature exceeds 70: during cooling or
indoor gas pipe temperature exceeds 70:during heating.
• Check the amount of gas and the refrigerant circuit.
• Check stop valve.
A failure is detected in the operation of the converter during operation.
• Replace the power board.
The bus-bar voltage exceeds 400V or falls to 200V or below during
compressor operating.
The bus-bar voltage exceeds 400V or falls to 50V or below during
compressor operating.
Failure occurs continuously 3 times within 30 seconds after the fan gets
started.
A short or open circuit is detected in the current sensor during compressor
operating.
Communication error occurs between the outdoor electronic control P.C.
board and power board for more than 10 seconds.
Zero cross signal cannot be detected while the compressor is operating.
• Replace the power board.
• Refer to 10-6.D "Check of outdoor fan motor".
• Replace the power board.
• Check the connecting wire between outdoor electronic control
P.C. board and power board.
• Check the connecting wire among outdoor electronic control
P.C. board, noise filter P.C. board and power board.
Outdoor electronic control P.C. board(Parts side)
NOTE 1. The location of LED is illustrated at the right figure. Refer to 10-7.1.
2. LED is lighted during normal operation.
LED2 LED1
The flashing frequency shows the number of times the LED blinks after every 2.5-second OFF.
(Example) When the flashing frequency is “2”.
0.5-second ON
ON
2.5-second OFF
• Reconnect compressor connector.
• Refer to 10-6.A "How to check inverter/compressor".
• Check the stop valve.
• Check the power module (PAM module).
2.5-second OFF
OFF
21
Lighting
0.5-second ON
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No. Symptom
Indication
LED1(Red) LED2(Yellow)
Outdoor unit
20 operates.
Once
Twice
Lighting
Lighting
21
Page 22
Condition
Abnormal point / Condition
Primary current protection
The input current exceeds 15A.
Secondary current protection
The current of the compressor exceeds 15A.
High-pressure protection
The indoor gas pipe temperature exceeds 45: during heating.
Defrosting in cooling
The indoor gas pipe temperature falls 3: or below during cooling.
The discharge temperature exceeds 100: during operation.
22
3 times
Lighting
Discharge temperature
protection
23
4 times
Lighting
Low discharge
temperature protection
The outdoor heat exchanger temperature exceeds 58:
during operation.
The unit is operated with emergency operation switch.
24
5 times
Lighting
Cooling high-pressure
protection
Outdoor unit
25 operates
9 times
Lighting
Inverter check mode
26
Lighting
Lighting
Normal
The frequency of the compressor is kept 80Hz or more and the discharge
temperature is kept under 39: for more than 20 minutes.
-
22
Correspondence
These symptoms do not mean any abnormality of the
product, but check the following points.
• Check if indoor filters are clogged.
• Check if refrigerant is short.
• Check if indoor/outdoor unit air circulation is short cycled.
• Check refrigerant circuit and refrigerant amount.
• Refer to 10-6.G "Check of LEV".
• Refer to 10-6.B "Check of outdoor thermistors".
• Refer to 10-6.G "Check of LEV".
• Check refrigerant circuit and refrigerant amount.
This symptom does not mean any abnormality of the
product, but check the following points.
• Check if indoor filters are clogged.
• Check if refrigerant is short.
• Check if indoor/outdoor unit air circulation is short cycled.
-
-
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Page 23
10-5. Trouble criterion of main parts
MUZ-GB50VA
Part name
Check method and criterion
Defrost thermistor
(RT61)
Measure the resistance with a tester.
Ambient temperature
thermistor (RT65)
Refer to 10-7. “Test point diagram and voltage”,1. “Outdoor electronic
control P.C. board”, the chart of thermistor.
Figure
Outdoor heat exchanger
temperature thermistor
(RT68)
Discharge temperature
thermistor (RT62)
Measure the resistance with a tester.
Before measurement, hold the thermistor with your hands to warm it up.
Fin temperature
thermistor (RT64)
Refer to 10-7. “Test point diagram and voltage”,1. “Outdoor electronic
control P.C. board”, the chart of thermistor.
Measure the resistance between terminals using a tester.
(Winding temperature : -10 °C ~ 40 °C)
Compressor
W
RED
Normal
V
WHT
0.40 " ~ 0.49 "
U
BLK
Measure the resistance between lead wires using a tester.
(Part temperature : -10 °C ~ 40 °C)
Outdoor fan motor
Normal
Color of lead wire
RED
U (W)
WHT
RED - BLK
BLK - WHT
WHT - RED
13.4 " ~ 16.4 "
BLK
V (V)
W (U)
Measure the resistance using a tester. (Part temperature : -10 °C ~ 40 °C)
R. V. coil
Normal
2.6 k" ~ 3.3 k"
Measure the resistance using a tester.(Part temperature : -10 °C ~ 40 °C)
WHT
Linear expansion valve
Normal
Color of lead wire
WHT - RED
RED - ORN
YLW - BRN
BRN - BLU
RED
LEV
ORN
37.4 " ~ 53.9 "
YLW BRN BLU
23
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Page 24
10-6. Troubleshooting flow
MUZ-GB50VA
A How to check inverter/ compressor
Disconnect the terminal of the compressor. 3 minutes after turning on the power supply, start
EMERGENCY OPERATION.
Measure the voltage between each
lead wire leading to the compressor.
U (BLK) - V (WHT)
V (WHT) - W (RED)
W (RED) - U (BLK)
Is voltage output on right table?
W • After the outdoor fan starts running, wait for 1 minute or more before
measuring the voltage.
• The output voltage values have the tolerance of i20%.
No
Yes
Is output balanced?
Yes
No
Is the input voltage to the outdoor electronic
control P.C. board 370V or more?
No
Replace the power board.
Yes
Turn off power supply of indoor and outdoor unit,
and measure the compressor winding resistance
between the compressor terminals.
Is the resistance between each terminal normal?
No
Replace the
compressor.
Yes
Reconnect the lead wire of compressor, and turn on
power supply to indoor and outdoor unit.
3 minutes later, start EMERGENCY OPERATION.
Clarify the causes by counting time until the inverter stops.
0 to 10 seconds: compressor rare short
10 to 60 seconds: compressor lock
60 seconds to 5minutes: refrigerant circuit defective
5 minutes or more: normal
24
COOL
HEAT
122V~154V
(56Hz~71Hz)
74V~126V
(30Hz~58Hz)
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Page 25
• When OPERATION INDICATOR lamp flashes 6-time.
• When thermistor is abnormal.
B Check of outdoor thermistors
Disconnect the connector in the outdoor electronic control P.C. board or the outdoor power board No
(see below table), and measure the resistance of thermistor. Is the thermistor normal?
Yes
Replace the thermistor.W
W When RT64 is abnormal,
replace the outdoor power
board.
Reconnect the connector CN661, CN663 and CN3.
3 minutes after turning on the power supply, start EMERGENCY OPERATION.
Does the unit operate 10 minutes or more without
showing thermistor abnormality?
No
Replace the outdoor electronic
control P.C. board.
Yes
Normal
Thermistor
Defrost
Discharge temperature
Outdoor heat exchanger temperature
Ambient temperature
Fin temperature
Symbol
RT61
RT62
RT68
RT65
RT64
Connector, Pin No.
Between CN661 pin1 and pin2
Between CN661 pin3 and pin4
Between CN661 pin7 and pin8
Between CN663 pin1 and pin2
Between CN3 pin1 and pin2
25
Board
Outdoor electronic control P.C. board
Outdoor power board
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Page 26
The cooling operation or heating operation does not operate. (LED display: Both LED1 and LED2 lighting)
C Check of R.V. coil
• When heating operation does not work.
1. Disconnect the lead wire leading to the compressor.
2. 3 minutes after turning on the power supply, start EMERGENCY
OPERATION in HEAT mode.
Is there voltage of 230V AC between pin1 and
pin 2 at connector CN912? W
No
Yes
Turn off power supply of indoor and outdoor unit.
Disconnect the connector
CN912 in noise filter P. C.
board. Is there normal
resistance to R.V. coil?
No
1. Turn off power supply of indoor and outdoor unit, and
disconnect the connector CN781 in the outdoor electronic
control P.C. board.
2. 3 minutes after turning on the power supply, start
EMERGENCY OPERATION in HEAT mode.
Is there voltage 12V DC
between the connector CN781
pin 5 (+) and pin 3 (-)?
Replace the R.V. coil.
No
Replace the electronic
control P.C. board.
Yes
Yes
Replace the noise filter P.C. board.
Replace the 4-way valve.
• When cooling operation does not work.
1. Disconnect the lead wire leading to the compressor.
2. 3 minutes after turning on the power supply, start EMERGENCY
OPERATION in COOL mode.
Is there voltage of 230V AC between pin1 and
pin 2 at connector CN912? W
No
Replace the 4-way valve.
Yes
1. Turn off power supply of indoor and outdoor unit, and
disconnect the connector CN781 in the outdoor electronic
control P.C. board.
2. 3 minutes after turning on the power supply, start
EMERGENCY OPERATION in COOL mode.
Is there voltage 12V DC
between the connector CN781
pin 5 (+) and pin 3 (-)?
No
Replace the noise filter P.C. board.
Yes
Replace the outdoor electronic control P.C. board.
26
W If the connector CN912 is
not connected or R.V. coil
is open, voltage occurs
between terminals even
when the control is OFF.
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Page 27
• Fan motor does not operate or stops operating shortly after starting the operation.
D Check of outdoor fan motor
Check the connection between the
connector CN931 and CN932.
Is the resistance between each terminal
of outdoor fan motor normal?
Yes
No
Disconnect CN932 from outdoor electronic control P.C. board, and
turn on the power supply.
Rotate the outdoor fan motor manually and measure the voltage of
CN931.
Between 1(+) and 5(-)
Between 2(+) and 5(-)
Between 3(+) and 5(-)
(Fixed to either 5V or 0V DC) No Does the voltage between each terminal become 5V DC and 0V DC
repeatedly?
No
Yes
Does the outdoor fan motor rotate smoothly?
Yes
Replace the outdoor electronic control P.C. board.
Replace the outdoor DC fan motor.
Outdoor unit does not operate. (LED display: display OFF)
E Check of power supply
Check the connecting of parts of main power supply circuit.
Turn on power supply.
Is there voltage of 230V AC in the
power supply terminal block?
No
Check the power supply cable.
Yes
Is the output voltage from the noise
filter P.C. board 230V AC?
No
Is fuse (F64) blown?
No
Yes
Yes
Is the input voltage to the power board
230V AC?
Replace the fuse.
No
Replace the reactor.
Yes
No
Is the input voltage to the outdoor
electronic control P.C. board 325V DC?
Replace the power board.
Yes
Replace the outdoor electronic control
P.C. board.
27
Replace the noise
filter P.C. board.
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Page 28
Outdoor unit does not operate at all, or stops immediately due to overcurrent.
F Check of current-limiting resistor
When the current-limiting resistor is open, the rush current limiting relay (X64) may not work properly.
Is the resistance of current-limiting
resistor (R64A or R64B) on the
noise filter P.C. board normal?
(Normal resistance : 10' i5%)
Not
open
Turn ON the power
supply and press
EMERGENCY
OPERATION switch.
Does LED on the outdoor
No
electronic control P.C. board
light up?
Yes
Replace the noise filter P.C.
board or the outdoor
electronic control P.C.
board.
Open
Replace the power P.C. board.
Does the rush current
limiting relay (X64) work
properly?
Yes
No
Replace the noise filter P.C. board.
● Check other electric parts in the main circuit together in the case that the current-limiting resistor is defective.
• When cooling, heat exchanger of non-operating indoor unit frosts.
• When heating, non-operating indoor unit gets warm.
G Check of LEV
Turn on power supply to the outdoor unit after checking LEV coil is mounted to the
LEV body securely.
Yes
Is "click - click" sound heard?
Or, do you feel vibration of the LEV coil with hands?
Normal
No
Disconnect the connector CN795.
Is there normal resistance to LEV coil?
Yes
No
Replace the LEV coil.
28
Replace the outdoor electronic
control P.C. board.
Replace the outdoor
electronic control P.C.
board or power P.C. board
or the compressor.
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Page 29
• When unit cannot operate neither by the remote controller nor by EMERGENCY OPERATION switch.
Indoor unit does not operate.
• When OPERATION INDICATOR lamp flashes ON and OFF every 0.5-second.
Outdoor unit doesn’t operate.
H How to check miswiring and serial signal error (when outdoor unit does not work)
Turn OFF the power supply.
Is there rated voltage in
the power supply?
No
Check the power
supply.
Yes
Turn ON the power supply.
Is there rated voltage between
outdoor terminal block S1 and
S2?
No
Check the wiring.
Yes
Press EMERGENCY OPERATION switch once.
Does the left lamp of OPERATION
INDICATOR lamp light up?
<Confirmation of the power to the indoor unit>
Yes
No
No
Is serial signal error indicated 6 minutes later?
Yes
Is there any miswiring,
poor contact, or wire
disconnection of the
indoor/outdoor
connecting wire?
Yes
Correct them.
No
A
Turn OFF the power supply.
Check once more if the indoor/outdoor
B connecting wire is not miswiring.
Short-circuit outdoor terminal block S2 and
S3.
W1
Turn ON the power supply.
Outdoor electronic control P.C. board
(Parts side)
LED2 LED1
Lighted Blinking
A
· Turn OFF inverter-controlled lighting
equipment.
· Turn OFF the power supply and then
turn ON again.
· Press EMERGENCY OPERATION
switch.
Is serial signal
error indicated
6 minutes later?
Yes
B
· Reinstall
either the
unit or the
light each
other away.
No
· Attach a filter
on remote
control
receiving
section of
the indoor
unit.
Does the LED on the outdoor electronic
control P.C. board repeat "3.6-second-OFF
and 0.8-second-ON quick blinking"? W3
No
(Lighted
or not
lighted)
Yes
Turn OFF the power supply.
Remove the short-circuit between
outdoor terminal block S2 and S3.
Turn ON the power supply.
Is there amplitude of 10 to 20V DC
between outdoor terminal block S2
and S3? <Confirmation of serial
signal>
W1. Miswiring may damage indoor electronic control
P.C. board during the operation.
Be sure to confirm the wiring is correct before the
operation starts.
W3.Be sure to check this within 3 minutes after turning
ON. After 3 minutes, LED blinks 6 times. Even when
the outdoor electronic control P.C. board is normal,
LED blinks 6 times after 3 minutes.
No
Replace the outdoor electronic
control P.C. board. W2
W2 Be careful to the residual
voltage of smoothing capacitor.
Is there any error of the
indoor/outdoor connecting wire,
such as the damage of the wire,
intermediate connection, poor
contact to the terminal block?
Yes
Replace the
indoor/outdoor
connecting wire.
No
Yes
Is there rated voltage between
indoor terminal block S1 and S2?
<Confirmation of power voltage>
No
Yes
Is there any error of the
indoor/outdoor connecting wire,
such as the damage of the wire,
intermediate connection, poor
contact to the terminal block?
No
Replace the indoor electronic control P.C. board.
Be sure to release the failure-mode
recall function after checking.
Refer to indoor unit service manual.
29
Yes Replace the
indoor/outdoor
connecting wire.
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Page 30
I Electromagnetic noise enters into TV sets or radios
No
Is the unit earthed?
Earth the unit.
Yes
Is the distance between the
antennas and the indoor
unit within 3m, or is the
distance between the
antennas and the outdoor
unit within 3m?
Yes
Extend the distance between
the antennas and the indoor
unit, and/or the antennas and
the outdoor unit.
No
Is the distance between the
TV sets or radios and the
indoor unit within 1m, or is
the distance between the TV
sets or radios and the
outdoor unit within 3m?
Yes
Extend the distance between
the TV sets and/or radios and
the indoor unit, or the TV sets
or radios and the outdoor unit.
No
Are the antennas damaged?
Is the coaxial cable damaged?
Is there any poor contact in
the antenna wiring?
Yes
Replace or repair the antenna.
Replace or repair the coaxial cable.
No
Is the indoor/outdoor
connecting wire of the air
conditioner and the wiring of
the antennas close?
Yes
Extend the distance between
the indoor/outdoor connecting
wire of the air conditioner and
the wiring of the antennas.
No
Even if all of the above conditions are fulfilled, the electromagnetic noise may enter, depending on
the electric field strength or the installation condition (combination of specific conditions such as
antennas or wiring).
Check the followings before asking for service.
1.Devices affected by the electromagnetic noise
TV sets, radios (FM/AM broadcast, shortwave)
2.Channel, frequency, broadcast station affected by the electromagnetic noise
3.Channel, frequency, broadcast station unaffected by the electromagnetic noise
4.Layout of ;
indoor/outdoor unit of the air conditioner, indoor/outdoor wiring, grounding wire, antennas, wiring
from antennas, receiver
5.Electric field intensity of the broadcast station affected by the electromagnetic noise
6.Presence or absence of amplifier such as booster
7.Operation condition of air conditioner when the electromagnetic noise enters in
1)Turn OFF the power supply once, and then turn ON the power supply. In this situation, check for
the electromagnetic noise.
2)Within 3 minutes after turning ON the power supply, press OPERATE/STOP (ON/OFF) button
on the remote controller for power ON, and check for the electromagnetic noise.
3)After a short time (3 minutes later after turning ON), the outdoor unit starts running. During
operation, check for the electromagnetic noise.
4)Press OPERATE/STOP (ON/OFF) button on the remote controller for power OFF, when the
outdoor unit stops but the indoor/outdoor communication still runs on. In this situation, check for
the electromagnetic noise.
30
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Page 31
10-7. Test point diagram and voltage
1. Outdoor electronic control P.C. board
MUZ-GB50VA
Defrost thermistor (RT61)
Ambient temperature thermistor (RT65)
Fin temperature thermistor (RT64) Outdoor heat exchanger temperature thermistor (RT68)
200
500
400
300
100 110 120
0
-20
-10
0
10
20
30
40
Temperature (°C)
(
(
(–)
(
(+)
(–)
(+)
(+)
(–)
(+) (
(
(
(
(
5V DC
pulse wave
5V
GND CN931
(
CN932
20-90V AC
50
10
(
To fan
motor
Temperature (;)
60
20
Temperature (°C)
CN781
90
LEV
80
10 20 30 40 50 60 70 80
12V
DC
70
70
30
0
GND (power board)
(–)Rush current relay
(–)R.V. coil
60
0
80
40
15V
15V
50
60
CN702
Signal reception
(From power board)
5V DC pulse wave
40
Outdoor heat exchanger
temperature thermistor (RT68)
30
Defrost thermistor (RT61)
Discharge temperature
thermistor (RT62)
20
(
10
80
20
(
(
0
100
40
(
0
120
GND
100
140
Ambient temperature
CN663
thermistor (RT65)
CN701
Signal transmission
(To power board)
5V DC pulse wave
200
90
Resistance (k")
160
100
CN795
12V DC
pulse wave
600
Resistance (k")
180
CN661
Resistance (k')
Discharge temperature thermistor (RT62)
700
LED 1
LED 2
CN801
325V DC
~
370V DC
Input
F801
FUSE
250V 3.15A
(
31
230V AC
Input
(
CN601
Serial signal
Room A
5~10V DC
OB455D--2qxp
07.9.3 5:23 PM
Page 32
2. Noise filter P.C. board
MUZ-GB50VA
CN901
To electronic CN902 CN903
control
To power To power
P.C. board
board
board
{
{
230V AC
Input
{
{
CN912
R.V. coil
230V AC
230V AC
Output
NR64 VARISTOR
F64 FUSE
250V 2A
F911 FUSE
250V 1A
32
230V AC
Output
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Page 33
3. Outdoor power board
MUZ-GB50VA
Connect to the compressor
Voltage among phases: 5V to
180V
325-370V DC
Output
(Red)
(+) 1
Connect to the earth
CN2
Connect to the controller board
(+)1-5(–): Signal transmission
(To electronic control P.C. board)
5V DC pulse wave
(+)2-5(–): Zero cross signal
3-4 : Not used
(+)6-5(–): 15V
(+)7-5(–): 15V
(–) 3
(White)
CN3
Fin temperature thermistor RT64
reception (From
) Signal
electronic control P.C. board)
5V DC pulse wave
CN5
Primary current detection
(Connect to the noise filter)
Connect to the compressor
Voltage among phases: 5V to 180V
Connect to the earth
325-370V DC
Output
(Red)
(+) 1
CN2
Connect to the controller board
(+)1-5(–): Signal transmission
(To electronic control P.C. board)
5V DC pulse wave
(+)2-5(–): Zero cross signal
3-4 : Not used
(+)6-5(–): 15V
(+)7-5(–): 15V
(–) 3
(White)
CN3
Fin temperature thermistor RT64
reception (From
) Signal
electronic control P.C. board)
5V DC pulse wave
CN5
Primary current detection
(Connect to the noise filter)
33
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11
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Page 34
DISASSEMBLY INSTRUCTIONS
<"Terminal with locking mechanism" Detaching points>
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.
(1) Slide the sleeve and check if there is a locking lever or not.
(2) The terminal with this connector has the
locking mechanism.
Sleeve
Locking lever
1Slide the sleeve.
2Pull the terminal while
pushing the locking
lever.
1Hold the sleeve, and
pull out the terminal
slowly.
Connector
MUZ-GB50VA
OPERATING PROCEDURE
PHOTOS
1. Removing the cabinet
Photo 1
(1)
(2)
(3)
(4)
(5)
(6)
(7)
Remove the screws of the service panel.
Remove the screws of the top panel.
Remove the screw of the valve cover.
Remove the service panel.
Remove the top panel.
Remove the valve cover.
Disconnect the power supply and indoor/ outdoor
connecting wire.
(8) Remove the screws of the cabinet.
(9) Remove the cabinet.
(10) Remove the screws of the back panel.
(11) Remove the back panel.
Screw of the top panel
Screws
of the
cabinet
Screws of the cabinet
Photo 3
Photo 2
Screw of the motor support
Screw of the service panel
Screws
of the
top
panel
Screws
of the
back
panel
Screws
of the
cabinet
Screw
of the
valve
cover
Set screws of the back panel
34
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Page 35
OPERATING PROCEDURE
PHOTOS
2. Removing the inverter assembly, inverter P.C. board
and power board
(1) Remove the top panel, cabinet and service panel.
(Refer to 1.)
(2) Remove the back panel.(Refer to 1.)
(3) Disconnect the following connectors;
<Electronic control P.C. board>
CN931 and CN932 (Fan motor)
CN795 (LEV)
CN661 (Discharge temperature thermistor, defrost
thermistor and outdoor heat exchanger
temperature thermistor)
CN663 (Ambient temperature thermistor)
<Noise filter P.C. board>
CN912 (R.V. coil)
(4) Remove the compressor connector.
(5) Remove the screws fixing the relay panel.
(6) Remove the inverter assembly.
(7) Disconnect all connectors and lead wires on the electronic
control P.C. board.
(8) Remove the electronic control P.C. board from the inverter
assembly.
(9) Remove the screws fixing the power board assembly.
(10) Disconnect all connectors and lead wires on the power
board.
(11) Remove the power board from the inverter assembly.
(12) Disconnect all connectors and lead wires on the noise filter
P.C. board.
(13) Remove the noise filter P.C. board from the inverter
assembly.
3. Removing R.V. coil
(1) Remove the top panel, cabinet and service panel.
(Refer to 1.)
(2) Remove the back panel. (Refer to 1.)
(3) Disconnect the following connectors;
<Noise filter P.C. board>
CN912 (R.V. coil)
(4) Remove the R.V. coil. (Photo 9)
35
Photo 4
Screws of the power board assembly
Screws of the relay panel
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Page 36
OPERATING PROCEDURE
PHOTOS
4. Removing the defrost thermistor, discharge temperature thermistor, outdoor heat exchanger temperature thermistor and ambient temperature thermistor
(1) Remove the top panel, cabinet and service panel.
(Refer to 1.)
(2) Remove the back panel. (Refer to 1.)
(3) Disconnect the following connectors;
<Electronic control P.C. board>
CN661 (Discharge temperature thermistor, defrost
thermistor and outdoor heat exchanger
temperature thermistor)
CN663 (Ambient temperature thermistor)
(4) Pull out the defrost thermistor from its holder. (Photo 6)
(5) Pull out the discharge temperature thermistor from its
holder. (Photo 5)
(6) Pull out the outdoor heat exchanger temperature thermistor
from its holder. (Photo 6)
(7) Pull out the ambient temperature thermistor from its holder.
(Photo 6)
Photo 5
Discharge temperature thermistor
Photo 6
Outdoor heat exchanger
temperature thermistor
Ambient
temperature
thermistor
Defrost
thermistor
5. Removing outdoor fan motor
Photo 7
(1) Remove the top panel, cabinet and service panel.
(Refer to 1.)
(2) Remove the back panel. (Refer to 1.)
(3) Disconnect the following connectors;
<Electronic control P.C. board>
CN931 and CN932 (Fan motor)
(4) Remove the propeller.
(5) Remove the screws fixing the fan motor.
(6) Remove the fan motor.
Propeller
36
Screws of the outdoor fan motor
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Page 37
OPERATING PROCEDURE
PHOTOS
6. Removing the compressor and 4-way valve
Photo 8
(1) Remove the top panel, cabinet and service panel.
(Refer to 1.)
(2) Remove the back panel. (Refer to 1.)
(3) Remove the inverter assembly. (Refer to 2.)
(4) Recover gas from the refrigerant circuit.
NOTE: Recover gas from the pipes until the pressure
gauge shows 0 kg/cm2 (0 MPa).
(5) Detach the welded part of the suction and the discharge
pipe connected with compressor. (Photo 9)
(6) Remove the compressor nuts.
(7) Remove the compressor.
(8) Detach the welded part of 4-way valve and pipe. (Photo 8)
Welded parts of 4-way valve
Photo 9
R.V. coil
Welded part
of the discharge pipe
Welded part
of the suction
pipe
7. Removing the reactor
Photo 10
(1) Remove the top panel. (Refer to 1.)
(2) Disconnect the reactor lead wire.
(3) Remove the screws of the reactor, and remove the reactor.
Screws of the reactor
37
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12
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Page 38
RoHS PARTS LIST (RoHS compliant)
MUZ-GB50VA
12-1. OUTDOOR UNIT STRUCTURAL PARTS, ELECTRICAL PARTS AND
FUNCTIONAL PARTS
25
24
29
28 27
26
23
22
1
21
2
20
3
19
4
5
6
18
7
16
8
15
13
9
38
10
11
14
17
12
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Page 39
MUZ-GB50VA
12-1. OUTDOOR UNIT STRUCTURAL PARTS, ELECTRICAL PARTS AND
FUNCTIONAL PARTS
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
30
31
32
33
34
35
RoHS
Part numbers that are circled are not shown in the illustration.
G
G
G
G
G
G
G
G
G
G
G
G
G
G
G
G
G
G
G
G
G
G
G
G
G
G
G
G
G
G
G
G
G
G
G
G
Part No.
E12
E12
E12
E12
E12
E12
E12
E12
E12
E12
E12
E12
E12
E12
E12
E12
E12
E12
E12
E12
E12
E12
E12
E12
E12
E12
E12
E12
E12
E12
E12
E12
E12
E12
E12
E12
819
851
938
851
851
819
819
819
C34
939
C06
851
821
851
851
935
891
819
819
C95
935
823
A87
935
935
851
935
819
817
851
127
737
935
851
853
861
297
630
301
501
290
232
009
521
506
900
900
661
662
640
493
490
961
650
245
450
374
375
337
444
309
308
440
233
009
515
382
382
385
936
299
936
Symbol
in Wiring
Diagram
Part Name
TOP PANEL
OUTDOOR HEAT EXCHANGER
OUTDOOR FAN MOTOR
MF
PROPELLER
BASE
CABINET
HANDLE
FAN GUARD
COMPRESSOR RUBBER SET
COMPRESSOR
MC
COMPRESSOR
MC
STOP VALVE(GAS)
STOP VALVE(LIQUID)
EXPANSION VALVE
LEV
EXPANSION VALVE COIL
R.V. COIL
21S4
4-WAY VALVE
VALVE COVER
SERVICE PANEL
OUTDOOR ELECTRONIC CONTROL P.C. BOARD
TERMINAL BLOCK
TB1
TERMINAL BLOCK
TB2
REACTOR
L
NOISE FILTER P.C. BOARD
AMBIENT TEMPERATURE THERMISTOR
RT65
THERMISTOR SET
RT61,RT62,RT68
POWER BOARD
BACK PANEL(OUT)
HANDLE
MOTOR SUPPORT
F801
FUSE
F911
FUSE
F64,NR64
FUSE & VARISTOR
CAPILLARY TUBE(TAPER PIPE)
OIL SEPARATOR
CAPILLARY TUBE
39
Q'ty/unit
Remarks
MUZ-GB50VA E1
E2
1
1
1
1
1
1
1
1
3
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
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
RC0J60-
3RUBBERS/SET
SNB130FLDH1
SNB130FLEH1
{12.7
{6.35
3P
3P
DEFROST, DISCHARGE
OUTDOOR HEAT EXCHANGER
Including heat sink and RT64
T3.15AL250V
T1AL250V
T2AL250V
{3.6x{2.4x50
{1.8x{0.6x1000
OB455D--2qxp
07.9.3 5:24 PM
Page 40
MUZ-GB50VA
12-2. ACCESSORY
No.
1
2
RoHS
1
G
G
Part No.
Part Name
2
Symbol
in Wiring
Diagram
E12 817 704 DRAIN SOCKET
E12 444 705 DRAIN CAP
Q'ty/unit
Remarks
MUZ-GB50VA E1
E2
1
2
1
2
[33
HEAD OFFICE: TOKYO BLDG., 2-7-3, MARUNOUCHI, CHIYODA-KU, TOKYO 100-8310, JAPAN
C Copyright 2006 MITSUBISHI ELECTRIC ENGINEERING CO.,LTD
Distributed in Sep. 2007. No. OB455 REVISED EDITION-D 6
Distributed in Jun. 2007. No. OB455 REVISED EDITION-C 6
Distributed in Apr. 2007. No. OB455 REVISED EDITION-B 6
Distributed in Aug. 2006. No. OB455 REVISED EDITION-A 6
Distributed in Mar. 2006. No. OB455 6
Made in Japan
New publication, effective Sep. 2007
Specifications subject to change without notice.