Mitsubishi Electric MUZ-GB50VA - E1MUZ-GB50VA - E2 User manual

SERVICE MANUAL
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
Wireless type
Models
MUZ-GB50VA -
MUZ-GB50VA - E2
E1
SPLIT-TYPE, HEAT PUMPAIR CONDITIONERS
OUTDOOR UNIT
Indoor unit service manual
MSZ-GB·VA Series (OB454)
Refrigerant service manual
R410A REFRIGERANT (OBR01)
NOTE:
• This service manual describes technical data of the outdoor units.
HFC
utilized
R410A
Please void OB455 REVISED EDITION-C.
Revision D:
•RoHS PARTS LIST has been changed.
No. OB455
REVISED EDITION-D
OB455D--1qxq 07.9.3 5:19 PM Page 1

2
1TECHNICAL CHANGES
MUZ-GA50VA - ➔MUZ- GB50VA - E1E1
1. Refrigerant filling capacity has been changed.
2. Outdoor electronic control P.C. board has been changed.
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- has been added.
•Check of outdoor thermistors(10-6.B) has been corrected.
E2
MUZ-GB50VA - ➔MUZ- GB50VA - E2E1
1. Compressor has been changed. (SNB130FLDH1 ➔SNB130FLEH1)
2. Outdoor electronic control P.C. board has been changed.
Revision C:
•RoHS PARTS LIST has been changed.
Revision D:
•RoHS PARTS LIST has been changed.
OB455D--1qxq 07.9.3 5:19 PM Page 2

3
PART NAMES AND FUNCTIONS
2
3SPECIFICATION
Air inlet
Piping
Air outlet
(back and side)
Drain hose
Drain outlet
MUZ-GB50VA
Outdoor model
Function
Power supply
Capacity Rated frequency(Min.-Max.)
Dehumidification
Air flow ✽1
(High/Low)
Power outlet
Running current ✽1
Power input ✽1
Power factor ✽1
Starting current ✽1
Compressor motor current ✽1
Fan motor current ✽1
Model
Output
Winding
resistance(at 20:)
Model
Winding
resistance(at 20:)
Dimensions WOHOD
Weight
Sound level ✽1
(High/Low)
Fan speed (High/Low)
Fan speed regulator
Refrigerant filling
capacity(R410A)
Refrigeration oil (Model)
kW
r/h
K/h
A
A
W
%
A
A
A
✽1
W
"
"
mm
kg
dB(A)
rpm
kg
Compressor
Fan motor
Special remarks Capacity
Electrical data
Coefficient of performance(C.O.P)
Single phase
230V,50Hz
20
97
7.46
0.32
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
2
1.50
NEO22
Cooling
5.0(0.9-5.8)
2.5
2,940/1,650
7.23
1,610
6.91
3.03
52/51
800/480
Heating
5.8(0.9-7.8)
—
2,940/2,210
7.43
1,660
7.11
3.41
55/53
800/620
MUZ-GB50VA
E1
E2
NOTE : Test conditions are based on ISO 5151.
Cooling : Indoor Dry-bulb temperature 27:Wet-bulb temperature 19:
Outdoor Dry-bulb temperature 35:Wet-bulb temperature 24:
Heating : Indoor Dry-bulb temperature 20:Wet-bulb temperature 15:
Outdoor Dry-bulb temperature 7:Wet-bulb temperature 6:
Refrigerant piping length (one way): 5m
✽1 Measured under rated operating frequency
ACCESSORIES
1
2
Drain socket
Drain cap [33 1
2
MUZ-GB50VA
OB455D--1qxq 07.9.3 5:19 PM Page 3

4
4NOISE CRITERIA CURVES
OUTDOOR UNIT
MICROPHONE
1m
Test conditions
Cooling : Dry-bulb temperature 35:
Wet-bulb temperature (24:)
Heating : Dry-bulb temperature 7:
Wet-bulb temperature 6:
COOLING
FUNCTION SPL(dB(A)) LINE
High
FAN SPEED
HEATING
52
55
90
80
70
60
50
40
30
20
10 63 125 250 500 1000 2000 4000 8000
NC-60
NC-50
NC-40
NC-30
NC-20
NC-70
BAND CENTER FREQUENCIES, Hz
APPROXIMATE
THRESHOLD OF
HEARING FOR
CONTINUOUS
NOISE
OCTAVE BAND SOUND PRESSURE LEVEL, 0dB=20µPa
MUZ-GB50VA
Specifications and rating conditions of main electric parts
Model
Item
Current transformer
Current transformer
Smoothing capacitor
Fuse
Fuse
Fuse
Expansion valve coil
Intelligent power module
Intelligent power module
Reactor
Power factor controller
Resistor
Resistor
Resistor
Solenoid coil relay
Terminal block
Terminal block
Relay
R.V. coil
MUZ-GB50VA
(CT1,2)
(CT61)
(CB1,2,3)
(F64)
(F801)
(F911)
(LEV)
(IPM)
(HC930)
(L)
(PFC)
(R64A,B)
(R937A,B)
(RS1~4)
(SSR61)
(TB1)
(TB2)
(X64)
(21S4)
ETQ19Z68AY
ETQ19Z53AY
560+450V
250V 2A
250V 3.15A
250V 1A
CAM-MD12ME
PS21244-A
PS21661-RZ
340µH 20A
PS51259-A
10"10W
1.1"2W 2%
0.04"7W
TLP3506
3P
3P
G4A
LD30013
OB455D--1qxq 07.9.3 5:19 PM Page 4

5
OUTLINES AND DIMENSIONS
5
Unit: mm
MUZ-GB50VA
30-
35-
155
90
198
40
515
299
66
34
51
330
360
850
430
500 80
121
840
Open as a rule
500 mm or more if
the front and both
sides are open
100 mm or more
200 mm or more if
there are obstacles
to both sides
Open as a rule
500 mm or more if the back,
both sides and top are open 350 mm or more
100 mm or more
Service panel
Gas refrigerant
pipe joint
Refrigerant pipe
(flared) [12.7
Liquid refrigerant
pipe joint
Refrigerant pipe
(flared) [6.35
REQUIRED SPACE
OB455D--1qxq 07.9.3 5:19 PM Page 5

WIRING DIAGRAM
6
6
MUZ-GB50VA
R64B
YLW
230V~
12-24V
CN912
CN663
WHT
BLU
NOISE FILTER P.C.BOARD
BRN
TO INDOOR UNIT CONNECTING
RED
S3
RT65
21
CN61
13
GRN/YLW
5
PFC
GRN
LD9
POWER BOARD
RT64
21
CN3
RED
WHT
RS2
RS1
R64A
RS3
RS4
F801
CN901
NR64
ELECTRONIC CONTROL P.C.BOARD
CB1
CB2
CB3
HC930
IPM
NF
BLK BLK BLK
BLK WHT RED YLW BLU ORN PNK GRY
BLU WHT
GRN
GRN
BLU
BLU
BLK
BLK
BLK
BLK
BLK
BLK
BLK
BLK
BLK
BLK
BLK RED
BLU
L
CT2 CT1
SSR61
U
6
CN7954123 78
CN661
W
CN4
TB2
S1
1
CN601
3
S2
1567
CN702
5321 CN781 13
CN701
12 12
CN931
LD1LD2
T801 R937A
R937B
CN801
23134512
MF
CN932
3X64 5123
LDE2
12
CT61
TAB1
F64
F911
LDE1
21S4
POWER SUPPLY ~/N 230V 50Hz
TAB2
N
PE
L
TB1
CIRCUIT BREAKER
4 1
RED YLW
3 2
RED
S R
21
CN903
21
CN902
21
CN5
6543 1
CN2 27
TAB4 V
MC
W
U
V
WHT
RT61 RT62 RT68 LEV
:Terminal block :Connector 3.Symbols below indicate. 2.Use copper conductors only (for field wiring).
diagram for servicing.
refer to the indoor unit electric wiring
1.About the indoor side electric wiringNOTES:
SYMBOL
NAME
SYMBOL
NAME
CURRENT TRANSFORMER
FUSE (T1AL 250V)
LEV EXPANSION VALVE COIL
LREACTOR
IPM INTELLIGENT POWER MODULE
CT61 FUSE (T2AL 250V)
F64
CT1, 2 CURRENT TRANSFORMER
HC930 INTELLIGENT POWER MODULE
F911
F801 FUSE (T3.15AL 250V)
SMOOTHING CAPACITOR
CB1~3 OUTDOOR FAN MOTOR
POWER FACTOR CONTROLLER
NOISE FILTER
RT61
DISCHARGE TEMPERATURE THERMISTOR
RS1~4 RESISTOR
R937A, B
RESISTOR
MF
MC COMPRESSOR
R64A,B RESISTOR
PFC
NF
NR64 VARISTOR
AMBIENT TEMPERATURE THERMISTOR
SOLENOID COIL RELAY
21S4 R.V. COIL
X64 RELAY
TB1 TERMINAL BLOCK TB2 TERMINAL BLOCK
RT65
FIN TEMPERATURE THERMISTOR
RT64
T801 TRANSFORMER
SSR61
RT68 OUTDOOR HEAT EXCHANGER
TEMPERATURE THERMISTOR
DEFROST THERMISTOR
RT62
NAME
SYMBOL
OB455D--1qxq 07.9.3 5:19 PM Page 6

7
7REFRIGERANT SYSTEM DIAGRAM
MUZ-GB50VA- E1 Unit:mm
Outdoor
heat
exchanger
Flared connection
Defrost
thermistor
RT61
Discharge
temperature
thermistor
RT62
Flared connection
Stop valve
Stop valve
(with service port)
Capillary tube
[3.6✕[2.4✕50
Refrigerant flow in cooling
Compressor
4-way valve
Refrigerant flow in heating
Refrigerant pipe [12.7
(with heat insulator)
Refrigerant pipe [6.35
(with heat insulator)
LEV R.V. coil
OFF
ON
Muffler
#100
Strainer
#100
Receiver
Outdoor heat
exchanger
temperature
thermistor
RT68
Ambient
temperature
thermistor
RT65
Strainer
#100
MUZ-GB50VA-
MUZ-GB50VA- E2
E1 Unit:mm
Outdoor
heat
exchanger
Flared connection
Defrost
thermistor
RT61
Discharge
temperature
thermistor
RT62
Flared connection
Stop valve
Stop valve
(with service port)
Capillary tube
[3.6✕[2.4✕50
Capillary tube
[1.8✕[0.6✕1000
Refrigerant flow in cooling
Compressor
4-way valve
Refrigerant flow in heating
Refrigerant pipe [12.7
(with heat insulator)
Refrigerant pipe [6.35
(with heat insulator)
LEV R.V. coil
heating ON
cooling OFF
Oil separator
Strainer
#100
Receiver
Outdoor
heat
exchanger
temperature
thermistor
RT68
Strainer
#100
Strainer
#100 Ambient
temperature
thermistor
RT65
OB455D--1qxq 07.9.3 5:19 PM Page 7

8
ADDITIONAL REFRIGERANT CHARGE (R410A:g)
Max. length
A
Max. Height
difference
B
Indoor
unit
Outdoor unit
MAX. REFRIGERANT PIPING LENGTH and MAX. HEIGHT DIFFERENCE
Max. length
A
30
Max. Height difference
B
15
Model Gas
12.7
Liquid
6.35
Piping size O.D : mm
Refrigerant piping : m
MUZ-GB50VA
Model
MUZ-GB50VA
Refrigerant piping length (one way)
Outdoor unit
precharged
1,500
15m
160
20m
260
25m
360
30m
460
7m
0
10m
60
Calculation : Xg=20g/m ✕ (Refrigerant piping length (m)–7)
NOTE : Refrigerant piping exceeding 7m requires additional refrigerant charge according to the calculation.
OB455D--1qxq 07.9.3 5:19 PM Page 8

9
PERFORMANCE CURVES8
The standard specifications apply only to the operation of the air conditioner under normal conditions. Since operating condi-
tions vary according to the areas where these units are installed, the following information has been provided to clarify the
operating characteristics of the air conditioner under the conditions indicated by the performance curve.
(1) GUARANTEED VOLTAGE
198 ~ 264V, 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]
(3) Outdoor intake air dry-bulb temperature : °C [DB]
(4) Total input: W
(5) Indoor intake air dry-bulb temperature : °C [DB]
(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.
}
}
Cooling
Heating
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.
MUZ-GB50VA
INDOOR UNIT OUTDOOR UNIT
Wet and dry-bulb
thermometers Wet and dry-bulb
thermometers
Indoor air Wet-bulb temperature
difference (:)
MSZ-GB50VA
8.7
8.0
7.3
6.6
5.9
5.3
at Rated frequency
Outdoor intake air Dry-bulb temperature (:) Outdoor intake air Dry-bulb temperature (:)
Indoor intake air Wet-bulb temperature (:)
Indoor intake air Wet-bulb temperature (:)
MUZ-GB50VA
8-1. Capacity and input curves
OB455D--1qxq 07.9.3 5:19 PM Page 9

10
Indoor air Dry-bulb temperature
difference (:)
Indoor intake air Dry-bulb temperature (:)
Outdoor intake air Wet-bulb temperature (:) Outdoor intake air Wet-bulb temperature (:)
Indoor intake air Dry-bulb temperature (:)
24.1
22.3
20.4
18.5
16.7
14.8
13.0
11.1
at Rated frequency
MUZ-GB50VA
MSZ-GB50VA
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
Capacity correction factors
Input correction factors
Input correction factors
Capacity correction factors
Correction of Cooling capacity
The operational frequency of compressor
Correction of Cooling total input
The operational frequency of compressor
Correction of Heating total input
The operational frequency of compressor
Correction of Heating capacity
The operational frequency of compressor
MUZ-GB50VA
(Hz)
0 50 100 150
0.0
0.5
1.0
1.5
(Hz) (Hz) (Hz)
0 50 100 150
0.0
0.5
1.0
1.5
0 50 100 150
0.0
0.5
1.0
1.5
0 50 100 150
0.0
0.5
1.0
1.5
0 50 100 150
0.0
0.5
1.0
1.5
2.0
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.
8-3. Test run operation (How to operate fixed-frequency operation)
OB455D--1qxq 07.9.3 5:19 PM Page 10

11
COOL operation
1Both indoor and outdoor unit are under the
same temperature/humidity condition.
2Operation : TEST RUN OPERATION (refer to 8-3.)
Dry-bulb temperature(:)Relative humidity(%)
20 50
25 60
30 70
8-4. OUTDOOR LOW PRESSURE AND OUTDOOR UNIT CURRENT
Ambient temperature(˚C)
Ambient humidity(%)
18 32
15 20
50 25 60 30 70 (%)
35(˚C)
Ambient temperature(˚C)
Ambient humidity(%)
18 32
15 20
50 25 60 30 70 (%)
35(˚C)
MUZ-GB50VA
(MPa [Gauge])
(kgf/F[Gauge])
Outdoor low pressure
Outdoor unit current(A)
4
5
6
7
8
0.5
0.6
0.7
0.8
0.9
1.0
5
6
7
8
9
10
1Condition :
2Operation : TEST RUN OPERATION (refer to 8-3.)
HEAT operation
Dry bulb temperature (°C) Indoor
20.0
14.5 2 1
Outdoor
7
615 12 20.0 14.5
Wet bulb temperature (°C)
0 5 10 15 20 25(˚C)
4
5
6
7
8
Outdoor unit current (A)
Ambient temperature(˚C)
MUZ-GB50VA
2
NOTE: The unit of pressure has been changed to MPa based on the international system of units (SI unit system).
The conversion factor is: 1(MPa [Gauge] = 10.2 (Kgf/ff [Gauge])
OB455D--1qxq 07.9.3 5:19 PM Page 11

12
MSZ-GB50VA : MUZ-GB50VA
21 18 5.88 3.00 0.51 1320 5.63 2.87 0.51 1386 5.40 2.75 0.51 1452 5.20 2.65 0.51 1518
21 20 6.13 2.39 0.39 1386 5.88 2.29 0.39 1469 5.70 2.22 0.39 1502 5.50 2.15 0.39 1568
22 18 5.88 3.23 0.55 1320 5.63 3.09 0.55 1386 5.40 2.97 0.55 1452 5.20 2.86 0.55 1518
22 20 6.13 2.63 0.43 1386 5.88 2.53 0.43 1469 5.70 2.45 0.43 1502 5.50 2.37 0.43 1568
22 22 6.38 1.98 0.31 1436 6.15 1.91 0.31 1526 6.00 1.86 0.31 1568 5.75 1.78 0.31 1634
23 18 5.88 3.47 0.59 1320 5.63 3.32 0.59 1386 5.40 3.19 0.59 1452 5.20 3.07 0.59 1518
23 20 6.13 2.88 0.47 1386 5.88 2.76 0.47 1469 5.70 2.68 0.47 1502 5.50 2.59 0.47 1568
23 22 6.38 2.23 0.35 1436 6.15 2.15 0.35 1526 6.00 2.10 0.35 1568 5.75 2.01 0.35 1634
24 18 5.88 3.70 0.63 1320 5.63 3.54 0.63 1386 5.40 3.40 0.63 1452 5.20 3.28 0.63 1518
24 20 6.13 3.12 0.51 1386 5.88 3.00 0.51 1469 5.70 2.91 0.51 1502 5.50 2.81 0.51 1568
24 22 6.38 2.49 0.39 1436 6.15 2.40 0.39 1526 6.00 2.34 0.39 1568 5.75 2.24 0.39 1634
24 24 6.70 1.81 0.27 1502 6.45 1.74 0.27 1584 6.30 1.70 0.27 1634 6.10 1.65 0.27 1716
25 18 5.88 3.94 0.67 1320 5.63 3.77 0.67 1386 5.40 3.62 0.67 1452 5.20 3.48 0.67 1518
25 20 6.13 3.37 0.55 1386 5.88 3.23 0.55 1469 5.70 3.14 0.55 1502 5.50 3.03 0.55 1568
25 22 6.38 2.74 0.43 1436 6.15 2.64 0.43 1526 6.00 2.58 0.43 1568 5.75 2.47 0.43 1634
25 24 6.70 2.08 0.31 1502 6.45 2.00 0.31 1584 6.30 1.95 0.31 1634 6.10 1.89 0.31 1716
26 18 5.88 4.17 0.71 1320 5.63 3.99 0.71 1386 5.40 3.83 0.71 1452 5.20 3.69 0.71 1518
26 20 6.13 3.61 0.59 1386 5.88 3.47 0.59 1469 5.70 3.36 0.59 1502 5.50 3.25 0.59 1568
26 22 6.38 3.00 0.47 1436 6.15 2.89 0.47 1526 6.00 2.82 0.47 1568 5.75 2.70 0.47 1634
26 24 6.70 2.35 0.35 1502 6.45 2.26 0.35 1584 6.30 2.21 0.35 1634 6.10 2.14 0.35 1716
26 26 6.90 1.59 0.23 1584 6.70 1.54 0.23 1667 6.60 1.52 0.23 1716 6.40 1.47 0.23 1766
27 18 5.88 4.41 0.75 1320 5.63 4.22 0.75 1386 5.40 4.05 0.75 1452 5.20 3.90 0.75 1518
27 20 6.13 3.86 0.63 1386 5.88 3.70 0.63 1469 5.70 3.59 0.63 1502 5.50 3.47 0.63 1568
27 22 6.38 3.25 0.51 1436 6.15 3.14 0.51 1526 6.00 3.06 0.51 1568 5.75 2.93 0.51 1634
27 24 6.70 2.61 0.39 1502 6.45 2.52 0.39 1584 6.30 2.46 0.39 1634 6.10 2.38 0.39 1716
27 26 6.90 1.86 0.27 1584 6.70 1.81 0.27 1667 6.60 1.78 0.27 1716 6.40 1.73 0.27 1766
28 18 5.88 4.64 0.79 1320 5.63 4.44 0.79 1386 5.40 4.27 0.79 1452 5.20 4.11 0.79 1518
28 20 6.13 4.10 0.67 1386 5.88 3.94 0.67 1469 5.70 3.82 0.67 1502 5.50 3.69 0.67 1568
28 22 6.38 3.51 0.55 1436 6.15 3.38 0.55 1526 6.00 3.30 0.55 1568 5.75 3.16 0.55 1634
28 24 6.70 2.88 0.43 1502 6.45 2.77 0.43 1584 6.30 2.71 0.43 1634 6.10 2.62 0.43 1716
28 26 6.90 2.14 0.31 1584 6.70 2.08 0.31 1667 6.60 2.05 0.31 1716 6.40 1.98 0.31 1766
29 18 5.88 4.88 0.83 1320 5.63 4.67 0.83 1386 5.40 4.48 0.83 1452 5.20 4.32 0.83 1518
29 20 6.13 4.35 0.71 1386 5.88 4.17 0.71 1469 5.70 4.05 0.71 1502 5.50 3.91 0.71 1568
29 22 6.38 3.76 0.59 1436 6.15 3.63 0.59 1526 6.00 3.54 0.59 1568 5.75 3.39 0.59 1634
29 24 6.70 3.15 0.47 1502 6.45 3.03 0.47 1584 6.30 2.96 0.47 1634 6.10 2.87 0.47 1716
29 26 6.90 2.42 0.35 1584 6.70 2.35 0.35 1667 6.60 2.31 0.35 1716 6.40 2.24 0.35 1766
30 18 5.88 5.11 0.87 1320 5.63 4.89 0.87 1386 5.40 4.70 0.87 1452 5.20 4.52 0.87 1518
30 20 6.13 4.59 0.75 1386 5.88 4.41 0.75 1469 5.70 4.28 0.75 1502 5.50 4.13 0.75 1568
30 22 6.38 4.02 0.63 1436 6.15 3.87 0.63 1526 6.00 3.78 0.63 1568 5.75 3.62 0.63 1634
30 24 6.70 3.42 0.51 1502 6.45 3.29 0.51 1584 6.30 3.21 0.51 1634 6.10 3.11 0.51 1716
30 26 6.90 2.69 0.39 1584 6.70 2.61 0.39 1667 6.60 2.57 0.39 1716 6.40 2.50 0.39 1766
31 18 5.88 5.35 0.91 1320 5.63 5.12 0.91 1386 5.40 4.91 0.91 1452 5.20 4.73 0.91 1518
31 20 6.13 4.84 0.79 1386 5.88 4.64 0.79 1469 5.70 4.50 0.79 1502 5.50 4.35 0.79 1568
31 22 6.38 4.27 0.67 1436 6.15 4.12 0.67 1526 6.00 4.02 0.67 1568 5.75 3.85 0.67 1634
31 24 6.70 3.69 0.55 1502 6.45 3.55 0.55 1584 6.30 3.47 0.55 1634 6.10 3.36 0.55 1716
31 26 6.90 2.97 0.43 1584 6.70 2.88 0.43 1667 6.60 2.84 0.43 1716 6.40 2.75 0.43 1766
32 18 5.88 5.58 0.95 1320 5.63 5.34 0.95 1386 5.40 5.13 0.95 1452 5.20 4.94 0.95 1518
32 20 6.13 5.08 0.83 1386 5.88 4.88 0.83 1469 5.70 4.73 0.83 1502 5.50 4.57 0.83 1568
32 22 6.38 4.53 0.71 1436 6.15 4.37 0.71 1526 6.00 4.26 0.71 1568 5.75 4.08 0.71 1634
32 24 6.70 3.95 0.59 1502 6.45 3.81 0.59 1584 6.30 3.72 0.59 1634 6.10 3.60 0.59 1716
32 26 6.90 3.24 0.47 1584 6.70 3.15 0.47 1667 6.60 3.10 0.47 1716 6.40 3.01 0.47 1766
INDOOR INDOOR
CAPACITY:5.0(kW) INPUT:1650(W)SHF:0.69
21 OUTDOOR DB(:) 25 27 30
WB(:)Q SHC SHF Q SHC SHF Q SHC SHF Q SHC SHFINPUT INPUT INPUT INPUT
DB(:)
PERFORMANCE DATA COOL operation at Rated frequency
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
OB455D--1qxq 07.9.3 5:19 PM Page 12

13
21 18 4.90 2.50 0.51 1617 4.50 2.30 0.51 1716 4.30 2.19 0.51 1749
21 20 5.15 2.01 0.39 1683 4.80 1.87 0.39 1766 4.60 1.79 0.39 1815
22 18 4.90 2.70 0.55 1617 4.50 2.48 0.55 1716 4.30 2.37 0.55 1749
22 20 5.15 2.21 0.43 1683 4.80 2.06 0.43 1766 4.60 1.98 0.43 1815
22 22 5.45 1.69 0.31 1749 5.10 1.58 0.31 1848 4.90 1.52 0.31 1881
23 18 4.90 2.89 0.59 1617 4.50 2.66 0.59 1716 4.30 2.54 0.59 1749
23 20 5.15 2.42 0.47 1683 4.80 2.26 0.47 1766 4.60 2.16 0.47 1815
23 22 5.45 1.91 0.35 1749 5.10 1.79 0.35 1848 4.90 1.72 0.35 1881
24 18 4.90 3.09 0.63 1617 4.50 2.84 0.63 1716 4.30 2.71 0.63 1749
24 20 5.15 2.63 0.51 1683 4.80 2.45 0.51 1766 4.60 2.35 0.51 1815
24 22 5.45 2.13 0.39 1749 5.10 1.99 0.39 1848 4.90 1.91 0.39 1881
24 24 5.75 1.55 0.27 1815 5.40 1.46 0.27 1898 5.25 1.42 0.27 1947
25 18 4.90 3.28 0.67 1617 4.50 3.02 0.67 1716 4.30 2.88 0.67 1749
25 20 5.15 2.83 0.55 1683 4.80 2.64 0.55 1766 4.60 2.53 0.55 1815
25 22 5.45 2.34 0.43 1749 5.10 2.19 0.43 1848 4.90 2.11 0.43 1881
25 24 5.75 1.78 0.31 1815 5.40 1.67 0.31 1898 5.25 1.31 0.25 1947
26 18 4.90 3.48 0.71 1617 4.50 3.20 0.71 1716 4.30 3.05 0.71 1749
26 20 5.15 3.04 0.59 1683 4.80 2.83 0.59 1766 4.60 2.71 0.59 1815
26 22 5.45 2.56 0.47 1749 5.10 2.40 0.47 1848 4.90 2.30 0.47 1881
26 24 5.75 2.01 0.35 1815 5.40 1.89 0.35 1898 5.25 1.21 0.23 1947
26 26 6.05 1.39 0.23 1881 5.70 1.31 0.23 1964 5.50 1.27 0.23 2013
27 18 4.90 3.68 0.75 1617 4.50 3.38 0.75 1716 4.30 3.23 0.75 1749
27 20 5.15 3.24 0.63 1683 4.80 3.02 0.63 1766 4.60 2.90 0.63 1815
27 22 5.45 2.78 0.51 1749 5.10 2.60 0.51 1848 4.90 2.50 0.51 1881
27 24 5.75 2.24 0.39 1815 5.40 2.11 0.39 1898 5.25 1.10 0.21 1947
27 26 6.05 1.63 0.27 1881 5.70 1.54 0.27 1964 5.50 1.49 0.27 2013
28 18 4.90 3.87 0.79 1617 4.50 3.56 0.79 1716 4.30 3.40 0.79 1749
28 20 5.15 3.45 0.67 1683 4.80 3.22 0.67 1766 4.60 3.08 0.67 1815
28 22 5.45 3.00 0.55 1749 5.10 2.81 0.55 1848 4.90 2.70 0.55 1881
28 24 5.75 2.47 0.43 1815 5.40 2.32 0.43 1898 5.25 1.00 0.19 1947
28 26 6.05 1.88 0.31 1881 5.70 1.77 0.31 1964 5.50 1.71 0.31 2013
29 18 4.90 4.07 0.83 1617 4.50 3.74 0.83 1716 4.30 3.57 0.83 1749
29 20 5.15 3.66 0.71 1683 4.80 3.41 0.71 1766 4.60 3.27 0.71 1815
29 22 5.45 3.22 0.59 1749 5.10 3.01 0.59 1848 4.90 2.89 0.59 1881
29 24 5.75 2.70 0.47 1815 5.40 2.54 0.47 1898 5.25 0.89 0.17 1947
29 26 6.05 2.12 0.35 1881 5.70 2.00 0.35 1964 5.50 1.93 0.35 2013
30 18 4.90 4.26 0.87 1617 4.50 3.92 0.87 1716 4.30 3.74 0.87 1749
30 20 5.15 3.86 0.75 1683 4.80 3.60 0.75 1766 4.60 3.45 0.75 1815
30 22 5.45 3.43 0.63 1749 5.10 3.21 0.63 1848 4.90 3.09 0.63 1881
30 24 5.75 2.93 0.51 1815 5.40 2.75 0.51 1898 5.25 0.79 0.15 1947
30 26 6.05 2.36 0.39 1881 5.70 2.22 0.39 1964 5.50 2.15 0.39 2013
31 18 4.90 4.46 0.91 1617 4.50 4.10 0.91 1716 4.30 3.91 0.91 1749
31 20 5.15 4.07 0.79 1683 4.80 3.79 0.79 1766 4.60 3.63 0.79 1815
31 22 5.45 3.65 0.67 1749 5.10 3.42 0.67 1848 4.90 3.28 0.67 1881
31 24 5.75 3.16 0.55 1815 5.40 2.97 0.55 1898 5.25 0.68 0.13 1947
31 26 6.05 2.60 0.43 1881 5.70 2.45 0.43 1964 5.50 2.37 0.43 2013
32 18 4.90 4.66 0.95 1617 4.50 4.28 0.95 1716 4.30 4.09 0.95 1749
32 20 5.15 4.27 0.83 1683 4.80 3.98 0.83 1766 4.60 3.82 0.83 1815
32 22 5.45 3.87 0.71 1749 5.10 3.62 0.71 1848 4.90 3.48 0.71 1881
32 24 5.75 3.39 0.59 1815 5.40 3.19 0.59 1898 5.25 0.58 0.11 1947
32 26 6.05 2.84 0.47 1881 5.70 2.68 0.47 1964 5.50 2.59 0.47 2013
INDOOR INDOOR
35 OUTDOOR DB(:) 40 43
WB(:)Q SHC SHF Q SHC SHF Q SHC SHFINPUT INPUT INPUT
DB(:)
CAPACITY:5.0(kW) INPUT:1650(W)SHF:0.69
PERFORMANCE DATA COOL operation at Rated frequency
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
MSZ-GB50VA : MUZ-GB50VA
OB455D--1qxq 07.9.3 5:19 PM Page 13

14
PERFORMANCE DATA HEAT operation at Rated frequency
CAPACITY:5.8(kW) INPUT:1700(W) 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
15
21
26
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
MSZ-GB50VA : MUZ-GB50VA
ACTUATOR CONTROL
9
MUZ-GB50VA
9-2. R.V. coil control
Heating . . . . . . . . . . . . . . . . ON
Cooling. . . . . . . . . . . . . . . . . OFF
Dry. . . . . . . . . . . . . . . . . . . . OFF
NOTE: The 4-way valve reverses for 5 seconds right before start-up of the compressor.
ON
OFF
ON
OFF
Outdoor fan
motor
Compressor
5 seconds 15 seconds
ON
OFF
Compressor
Outdoor fan
motor
ON
OFF
<COOL>
5 seconds
<HEAT>
5 seconds
R.V.coil ON
OFF ON or OFF ON or OFF
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.
NOTE Q : Total capacity (kW) INPUT : Total power input (W) DB : Dry-bulb temperature WB : Wet-bulb temperature
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15
10 TROUBLESHOOTING
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.
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 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 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
MUZ-GB50VA
9-3. Relation between main sensor and actuator
Discharge temperature thermistor
Indoor pipe temperature thermistor
Defrost thermistor
Fin temperature thermistor
Outdoor heat exchanger temperature
Ambient temperature thermistor
Purpose
Protection
Defrosting Protection
Defrosting
Protection
Protection
Protection
Compressor
LEV Outdoor
fan motor R.V. coil
Sensor Actuator
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16
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.
10-2. Failure mode recall function
1. Flow chart of failure mode recall function for the indoor/outdoor unit
Operational procedure
Yes
(Blinks)
No
(OFF)
Yes
No
Releasing the failure mode recall function
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:
W3.Blinking pattern when the outdoor unit is abnormal:
ON
OFF Beeps
Repeated cycle Repeated cycle
ON
OFF No beep Beeps
Repeated cycle
2.5-second OFF Blinking at 0.5-
second interval
2.5-second OFF 3-second ON Blinking at 0.5-
second interval
Beeps Repeated cycle
2.5-second OFF Blinking at 0.5-
second interval
No beep Beeps
Repeated cycle
2.5-second OFF 3-second ON Blinking at 0.5-
second interval
Repeated cycle
Beeps
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
The cause of abnormality cannot be found because the abnormality doesn't recur.
Setting up the failure mode recall function
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.
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
Turn ON the power supply.
<Preparation of the remote controller>
1While pressing both OPERATION SELECT
button and TOO COOL button on the remote controller at the same time, press
RESET button.
2First, 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.
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.
Repair the defective parts.
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.
Judgment of indoor/outdoor abnormality
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
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)
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
W1. Regardless of normal or abnormal condition, a short
beep is emitted once the signal is received.
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17
2. Flow chart of the detailed outdoor unit failure mode recall function
Operational procedure
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:
Yes
(Blinks)
No
(OFF)
ON
OFF No beep Beeps
Repeated cycle
2.5-second OFF 3-second ON Blinking at 0.5-
second interval
No beep Beeps
Repeated cycle
2.5-second OFF 3-second ON Blinking at 0.5-
second interval
Repeated cycle
W1. Regardless of normal or abnormal condition, 2 short
beeps are emitted as the signal is received.
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
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.
Repair the defective parts.
With the remote controller headed towards the indoor unit, press TOO COOL or TOO
WARM button to adjust the set temperature to 25:. W1
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.
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
Release the failure mode recall function according
to the left mentioned procedure.
Confirm that the remote controller is in the failure mode recall
function.
The outdoor unit might be abnormal.
Confirm if outdoor unit is abnormal according to the following procedures.
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18
OFF None (Normal)
2-time flash
3-time flash
4-time flash
5-time flash
6-time flash
7-time flash
8-time flash
Lighting Lighting
Lighting Once
Lighting Once
Lighting Twice
Lighting 3 times
Lighting 4 times
Lighting 9 times
Once Goes
out
Lighting Lighting
Lighting Lighting
3 times Goes
out
4 times Goes
out
Lighting Lighting
Lighting Lighting
Lighting 5 times
9-time flash
10-time flash
•Check the connection
of the compressor
connecting wire.
•Refer to 10-6.A
"How to check
inverter / compressor".
•Check the stop valve.
•Replace the outdoor
electronic control
P.C. board.
•Check refrigerant circuit
and refrigerant amount.
•Refer to 10-6.G"Check
of LEV".
•Refer to 10-6.D"Check
of outdoor fan motor".
•Replace the outdoor
electronic control
P.C. board.
•Check refrigerant circuit
and refrigerant amount.
•Refer to 10-6.G"Check
of LEV".
•Reconnect compressor
connector.
•Refer to 10-6.A"How to
check inverter/
compressor."
•Check the stop valve.
•Check refrigerant circuit
and refrigerant amount.
•Check the stop valve.
•Check around outdoor
unit.
•Check outdoor unit air
passage.
•Refer to 10-6.D"Check
of outdoor fan motor".
•Refer to 10-6.B"Check
of outdoor thermistors".
•Refer to 10-6.B "Check
of outdoor thermistors".
Overcurrent protection stop is
continuously performed 3 times within
1 minute after the compressor gets
started, or converter protection stop or
bus-bar voltage protection stop is
continuously performed 3 times within
3 minutes after start-up.
Thermistor shorts or opens during
compressor running.
28A current flows into intelligent
power module.
Tthe outdoor heat exchanger
temperature exceeds 70:during
cooling or the indoor gas pipe
temperature exceeds 70:during
heating.
The fin temperature exceeds 87:
during operation.
The P.C. board temperature exceeds
70:during operation.
Failure occurs continuously 3 times
within 30 seconds after the fan gets
started.
Nonvolatile memory data cannot be
read properly.
The frequency of the compressor is
kept 80Hz or more and the discharge
temperature is kept under 39:
for more than 20 minutes.
Outdoor power system
Discharge temperature
thermistor
Defrost thermistor
Ambient temperature thermistor
Fin temperature thermistor
P.C. board temperature
thermistor
Outdoor heat exchanger
temperature thermistor
Overcurrent
Discharge temperature
High pressure
Fin temperature
P.C. board temperature
Outdoor fan motor
Nonvolatile memory data
Discharge temperature
--
Abnormal point
(Failure mode / protection) Condition Correspondence
Indoor/outdoor
unit failure mode
recall function
LED indication
(Outdoor P.C. board)
LED 1 LED 2
Discharge temperature exceeds
116°C during operation.
Compressor can restart if discharge
temperature thermistor reads 100:or
less 3 minutes later.
The left lamp of
OPERATION INDICATOR
lamp (Indoor unit)
NOTE : Blinking patterns of this mode differ from the ones of Troubleshooting check table (10-4.).
MUZ-GB50VA
3. Outdoor unit failure mode table
OB455D--1qxq 07.9.3 5:20 PM Page 18

19
11-time flash
•Check the connecting
wire between outdoor
electronic control
P.C. board and power
board.
•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.
The communication between boards
protection stop is continuously
performed twice.
Communication error occurs between
the electronic control P.C. board and
power board for more than 10 seconds.
Current sensor protection stop is
continuously performed twice.
A short or open circuit is detected
in the current sensor during
compressor operating.
The protection stop of the zero
cross detecting circuit is continuously
performed 10 times.
Zero cross signal cannot be detected
while the compressor is operating.
A failure is detected in the operation
of the converter during operation.
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.
Communication error
between P.C. boards
Current sensor
Zero cross detecting circuit
Converter
Bus-bar voltage
(1)
Bus-bar voltage
(2)
wEven if this protection stop is
performed continuously 3 times,
it does not mean the abnormality
in outdoor power system.
Lighting 6 times
Lighting 7 times
5 times Goes
out
5 times Goes
out
5 times
6 times
Goes
out
Goes
out
Abnormal point
(Failure mode / protection) Condition Correspondence
Indoor/outdoor
unit failure mode
recall function
LED indication
(Outdoor P.C. board)
LED 1 LED 2
The left lamp of
OPERATION INDICATOR
lamp (Indoor unit)
NOTE : Blinking patterns of this mode differ from the ones of Troubleshooting check table (10-4.).
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