Mitsubishi Electric MUZ-GB50VA User manual

SERVICE MANUAL
CONTENTS
1. TECHNICAL CHANGES ··································· 3
2. PART NAMES AND FUNCTIONS····················· 4
3. SPECIFICATION················································ 4
4. NOISE CRITERIA CURVES ······························ 6
5. OUTLINES AND DIMENSIONS ························ 6
6. WIRING DIAGRAM············································ 7
7. REFRIGERANT SYSTEM DIAGRAM ··············· 9
8. PERFORMANCE CURVES ····························· 11
9. ACTUATOR CONTROL··································· 16
10. SERVICE FUNCTIONS···································· 17
11. TROUBLESHOOTING ····································· 18
12. DISASSEMBLY INSTRUCTIONS···················· 44
13. RoHS PARTS LIST·········································· 48
Models
MUZ-GB50VA - E1
MUZ-GB50VA - E2
MUZ-GB50VA - E3
OUTDOOR UNIT
Indoor unit service manual
MSZ-GB·VA Series (OB454)
NOTE:
• This service manual describes technical data of the outdoor units.
HFC
utilized
R410A
Please void OB455 REVISED EDITION-F.
No. OB455
REVISED EDITION-G
Revision G:
• Errors in TROUBLESHOOTING have been
corrected.

2
Revision A:
• Compressor has been changed.
Model RoHS PARTS LIST number
Previous SNB130FLDH E12 851 900
New SNB130FLDH1 E12 939 900
Revision B:
• REFRIGERANT SYSTEM DIAGRAM has been changed.
• Oil separator has been added.
• Capillary tube has been added. (ø1.8 × ø0.6 × 1000)
• MUZ-GB50VA- E2 has been added.
• Check of outdoor thermistors (10-6. ) has been corrected.
Revision C:
• RoHS PARTS LIST has been changed.
Revision D:
• RoHS PARTS LIST has been changed.
Revision E:
• MUZ-GB50VA- E3 has been added.
Revision F:
• The fan guard for MUZ-GB50VA- E1 , E2 , E3 has been changed.
Use the specified refrigerant only
Never use any refrigerant other than that specified.
Doing so may cause a burst, an explosion, or fire when the unit is being used, serviced, or disposed of.
Correct refrigerant is specified in the manuals and on the spec labels provided with our products.
We will not be held responsible for mechanical failure, system malfunction, unit breakdown or accidents caused by
failure to follow the instructions.
Revision G:
• Errors in TROUBLESHOOTING have been corrected.

3
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.
TECHNICAL CHANGES
1
MUZ-GB50VA - E2 MUZ-GB50VA - E3
1. Compressor has been changed. (SNB130FLEH1 SNB130FGBH)
2. Outdoor electrical parts have been changed.
3. Refrigerant circuit has been changed.

44
PART NAMES AND FUNCTIONS
2
3SPECIFICATION
Air inlet
Piping
Air outlet
(back and side)
Drain hose
Drain outlet
MUZ-GB50VA
ACCESSORIES
Drain socket 1
Drain cap ø33 2
Outdoor model MUZ-GB50VA
Function Cooling Heating
Power supply Single phase 230 V, 50 Hz
Capacity Rated frequency (Min.-Max.) kW 5.0 (0.9-5.8) 5.8 (0.9-7.8)
Electrical
data
Breaker capacity A 20
Running current 1 A 7.23 7.43
Power input 1 W 1,610 1,660
Power factor 1% 97
Starting current 1 A 7.46
Coefficient of performance (C.O.P) 1 3.03 3.41
Compressor
Model
E1 SNB130FLDH or SNB130FLDH1
E2 SNB130FLEH1
E3 SNB130FGBH
Output E1, E2 W850
E3 900
Compressor motor current 1 A 6.91 7.11
Fan motor Model RC0J60-AA
Current 1 A 0.32
Dimensions W × H × D mm 840 × 850 × 330
Weight kg 53
Dehumidification /h 2.2 —
Air flow 1 (High/Low) m3/h 2,940/1,650 2,940/2,210
Special
remarks
Sound level 1 (High/Low) dB(A) 52/51 55/53
Fan speed (High/Low) rpm 800/480 800/620
Fan speed regulator 2
Refrigerant filling capacity (R410A) kg 1.50
Refrigeration oil (Model) NEO22
NOTE : Test conditions are based on ISO 5151.
Cooling : Indoor Dry-bulb temperature 27°C Wet-bulb temperature 19°C
Outdoor Dry-bulb temperature 35°C Wet-bulb temperature 24°C
Heating : Indoor Dry-bulb temperature 20°C Wet-bulb temperature 15°C
Outdoor Dry-bulb temperature 7°C Wet-bulb temperature 6°C
Refrigerant piping length (one way) : 5 m
1 Measured under rated operating frequency.

55
Specifications and rated conditions of main electric parts
Model
Item
MUZ-GB50VA- E1
MUZ-GB50VA- E2
Current transformer (CT1,2) 20 A
(CT61) 20 A
Smoothing capacitor (CB1,2,3) 560 μF 450 V
Fuse
(F64) 250 V 2 A
(F801) 250 V 3.15 A
(F911) 250 V 1 A
Expansion valve coil (LEV) DC 12 V
Intelligent power module (IPM) 15 A 600 V
(HC930) 3 A 600 V
Reactor (L) 340 μH 20 A
Power factor controller (PFC) 20 A 600 V
Resistor
(R64A,B) 10 Ω10 W
(R937A,B) 1.1 Ω2 W 2%
(RS1~4) 0.04 Ω7 W
Solenoid coil relay (SSR61) 0.5 A 600 V
Terminal block (TB1,TB2) 3 P
Relay (X64) 20 A 250 V
R.V. coil (21S4) AC 220 - 240 V
Model
Item MUZ-GB50VA- E3
Current transformer (CT) 20 A
(CT761, CT781) 15 A
Smoothing capacitor (C61, C62, C63) 620 μF 420 V
Diode module (DB61) 25 A 600 V
(DB65) 25 A 600 V
Fuse (F61) T20AL250V
(F701, F801, F901) T3.15AL250V
Intelligent power module (IPM) 20 A 600 V
Expansion valve coil (LEV) DC 12 V
Reactor (L61) 23.0 mH
Current-detecting resistor
(R61, R62) 180 mΩ5 W (2 elements)
(R825) 25 mΩ5 W
(R937A, R937B) 1.1 Ω2 W
Current-limiting PTC thermistor (PTC64, PTC65) 33 Ω
Terminal block (TB1, TB2) 3 P
Relay (X63) 3 A 250 V
(X64) 20 A 250 V
R.V. coil (21S4) AC 220 - 240 V
IGBT (TR821) 30 A 600 V

6
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) ø12.7
Liquid refrigerant
pipe joint
Refrigerant pipe
(flared) ø6.35
REQUIRED SPACE
4NOISE CRITERIA CURVES
OUTDOOR UNIT
MICROPHONE
1m
Test conditions
Cooling : Dry-bulb temperature 35°C
Wet-bulb temperature (24°C)
Heating : Dry-bulb temperature 7°C
Wet-bulb temperature 6°C
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, dB re 0.0002 MICRO BAR
MUZ-GB50VA

7
WIRING DIAGRAM
6
7
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
1 567
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 wiri
n
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
MUZ-GB50VA- E1
MUZ-GB50VA- E2

8
MUZ-GB50VA- E3

9
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
ø3.6×ø2.4×50
Refrigerant flow in cooling
Compressor
4-way valve
Refrigerant flow in heating
Refrigerant pipe ø12.7
(with heat insulator)
Refrigerant pipe ø 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
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
ø3.6×ø2.4×50
Capillary tube
ø1.8×ø0.6×1000
Refrigerant flow in cooling
Compressor
4-way valve
Refrigerant flow in heating
Refrigerant pipe ø 12.7
(with heat insulator)
Refrigerant pipe
ø 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
MUZ-GB50VA- E1
MUZ-GB50VA- E2

10
Max. Length
A
Max. Height
difference
B
Indoor
unit
Outdoor unit
MUZ-GB50VA- E3 Unit: mm
Outdoor
heat
exchanger
Flared connection
Defrost
thermistor
RT61
Discharge
temperature
thermistor
RT62
Flared connection
Stop valve
(with strainer)
Stop valve
(with service port)
Capillary tube
ø3.6×ø2.4×50
Refrigerant flow in cooling
Compressor
4-way valve
Refrigerant flow in heating
Refrigerant pipe ø12.7
(with heat insulator)
Refrigerant pipe ø 6.35
(with heat insulator)
LEV R.V. coil
OFF
ON
Muffler
#100
Receiver
Outdoor heat
exchanger
temperature
thermistor
RT68
Ambient
temperature
thermistor
RT65
Strainer
#100
ADDITIONAL REFRIGERANT CHARGE (R410A : g)
Model Outdoor unit
precharged
Refrigerant piping length (one way)
7 m 10 m 15 m 20 m 25 m 30 m
MUZ-GB50VA 1,500 0 60 160 260 360 460
Calculation : X g = 20 g/m × (Refrigerant piping length (m) - 7)
NOTE : Refrigerant piping exceeding 7 m requires additional refrigerant charge according to the calculation.
MAX. REFRIGERANT PIPING LENGTH and MAX. HEIGHT DIFFERENCE
Refrigerant piping : m Piping size O.D : mm
Max. Length
A
Max. Height difference
BGas Liquid
MUZ-GB50VA 30 15 12.7 6.35