Mitsubishi Electric MSZ-GB50VA Series User manual

SERVICE MANUAL
CONTENTS
1. TECHNICAL CHANGES ····································2
2. PART NAMES AND FUNCTIONS······················3
3. SPECIFICATION·················································5
4. NOISE CRITERIA CURVES·······························6
5. OUTLINES AND DIMENSIONS ·························7
6. WIRING DIAGRAM ············································8
7. REFRIGERANT SYSTEM DIAGRAM················8
8. SERVICE FUNCTIONS ······································9
9. TROUBLESHOOTING······································10
10. DISASSEMBLY INSTRUCTIONS·····················24
11. RoHS PARTS LIST···········································27
12. OPTIONAL PARTS···········································30
Wireless type
Models
MSZ-GB50VA - E1
SPLIT-TYPE, HEAT PUMPAIR CONDITIONERS
MSZ-GB50VA
NOTE:
• This service manual describes technical data of the indoor units.
INDOOR UNIT
Outdoor unit service manual
MUZ-GB·VA series (OB455)
MXZ-A·VA series (OB377)
MXZ-8A140VA (OC316)
No. OB454
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2
1TECHNICAL CHANGES
MSZ-GA50VA - ➔MSZ-GB50VA -
Indoor unit size has been changed. (W1,100 mm x H325 mm x D258 mm ➔ W780 mm x H298 mm x D210 mm)
E1E1
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3
PART NAMES AND FUNCTIONS
2
INDOOR UNIT
MSZ-GB50VA
Line flow fan
Air outlet
Vertical vane
Air inlet
Display section
Front panel
Panel
Heat exchanger
Horizontal vane
Operation section
(When the front panel is opened)
Remote controller
Remote control
receiving section
Catechin air filter
Air cleaning filter (Option)
(Anti-Allergy Enzyme
Filter,Blue bellows type)
Emergency operation switch
Fan guard
Operation Indicator
lamp
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4
ACCESSORIES
1
2
3
4
5
6
7
Installation plate
Installation plate fixing screw 4 o25 mm
Remote controller holder
Fixing screw for 33.5 o1.6 mm (Black)
Battery (AAA) for remote controller
Wireless remote controller
Felt tape (Used for left or left-rear piping)
1
5
1
2
2
1
1
REMOTE CONTROLLER
ON-TIMER button
CLOCK SET button
TIME SET buttons
FORWARD button
BACKWARD button
OFF-TIMER button
(This diagram shows an overall view.)
Open the front lid.
RESET button VANE CONTROL button
Signal transmitting section
Operation display section
Temperature buttons
OPERATE/STOP
(ON/OFF) button
FAN SPEED CONTROL button
OPERATION SELECT button
ECONO COOL button
Indication of
remote controller
model is on back
MSZ-GB50VA
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5
SPECIFICATION
3
MSZ-GB50VA
T3.15AL 250V
MSBPC20M16 12V DC 250"(at 25˚C)
ERZV14D471
3P
INDOOR UNIT
Item
Fuse
Horizontal vane motor
Varistor
Terminal block
(F11)
(MV)
(NR11)
(TB)
Specifications and rating conditions of main electric parts
MSZ-GB50VA
Indoor model
Function
Power supply Single phase
230V,50Hz
684
654/445/414
20
0.35
40
50
0.35
RC0J30-CC
780O298O210
9
4
1,300
1,200/1,100/900
4
KM05B
Cooling
48/44/38/32
Heating
48/42/36/30
Air flow(Super High)
Air flow(High/Med./Low)
Power outlet
Running current ✽1
Power input ✽1
Power factor ✽1
Fan motor current ✽1
Model
Dimensions WOHOD
Weight
Air direction
Sound level(Super High/High/Med./Low)
Fan speed(Super High)
Fan speed(High/Med./Low)
Fan speed regulator
Remote controller model
K/h
K/h
A
A
W
%
A
mm
kg
dB(A)
rpm
rpm
Electrical data
Fan motor
Special remarks
Capacity
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.
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6
OUTLINES AND DIMENSIONS
5
Unit : mm
INDOOR UNIT
155 155
335 320
41.5 215
42.5 214
3287.5
7055
5555 225 225
or more7
100
90
106
298
102624.5
780
210 5
53.5
19
159
58
14273.5
234
Air in
Air out
Wall hole [65
Indoor unit
Installation plate
Installation plate
11x20 Oblong hole
11x26 Oblong hole
10 or more
75 or more
66 or more
W
75 or more
W
In case of left, left back, or
left under piping (using spacer), 115 or more
Insulation [28
Drain hose [16
(Connected part O.D)
Liquid line [8.0-0.5m
Gas line [9.52-0.43m
Insulation [35 O.D
[19 I.D
{
Required space (Indoor unit)
MSZ-GB50VA
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7
4NOISE CRITERIA CURVES
90
80
70
60
50
40
30
20
10 63 125 250 500 1000 2000 4000 8000
OCTAVE BAND SOUND PRESSURE LEVEL, 0dB=20µPa
BAND CENTER FREQUENCIES, Hz
APPROXIMATE
THRESHOLD OF
HEARING FOR
CONTINUOUS
NOISE
NC-60
NC-50
NC-40
NC-30
NC-20
NC-70
Test conditions,
Cooling : Dry-bulb temperature 27: Wet-bulb temperature 19:
48
SPL(dB(A)) LINE
High
FAN SPEED
Heating : Dry-bulb temperature 20: Wet-bulb temperature 15:
MSZ-GB50VA
INDOOR UNIT WALL
MICROPHONE
0.8m
1m
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8
6WIRING DIAGRAM
REFRIGERANT SYSTEM DIAGRAM
7
MSZ-GB50VA
Indoor
heat
exchanger
Flared connection
Room temperature
thermistor
RT11
Indoor coil
thermistor
RT13(sub)
Flared connection
Refrigerant flow in cooling
Refrigerant flow in heating
Refrigerant pipe [12.7
(with heat insulator)
Refrigerant pipe [6.35
(with heat insulator)
Indoor coil
thermistor
RT12(main)
Distributor
INDOOR UNIT
Unit : mm
INDOOR UNIT
SYMBOL
DB111
F11
MF
MV
NR11
SYMBOL
RT11
RT12
RT13
T111
TB
NAME
DIODE STACK
FUSE (T3.15AL250V)
INDOOR FAN MOTOR
VANE MOTOR (HORIZONTAL)
VARISTOR
NAME
ROOM TEMPERATURE THERMISTOR
INDOOR COIL THERMISTOR (MAIN)
INDOOR COIL THERMISTOR (SUB)
TRANSFORMER
TERMINAL BLOCK
NOTE:1. About the outdoor side electric wiring refer to the outdoor unit electric wiring diagram for servicing.
2. Use copper conductors only. (For field wiring)
3. Symbols below indicate.
/: Terminal block, : Connector
MSZ-GB50VA
4
3
2
1
S2
POWER MONITOR
RECEIVER P.C.BOARD
26
230V~
BLU
INDOOR ELECTRONIC
CONTROL P.C. BOARD
SW P.C.
BOARD
INTERLOCK
SWITCH(FAN)
5
MV
TO OUTDOOR
UNIT
CONNECTING
BLK
RED
S3
TB TAB3
DB111
NR11
F11
5
6
4
2
2
LD
105(T)
LD
101(A)
12-24V
RT13
1R1
CN
GRN
LD104
CN201
2
1
151
CN
T111
RED
WHT
111
CN
CN
112
CN211 BLU
YLW
BLK
MF
RT11
RT12
1
3
5
S1
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9
SERVICE FUNCTIONS
8
8-2. P.C. BOARD MODIFICATION FOR INDIVIDUAL OPERATION
A maximum of 4 indoor units with wireless remote controllers can be used in a room.
In this case, to operate each indoor unit individually by each remote controller, P.C. boards of remote controller must be
modified according to the number of the indoor unit.
8-1. TIMER SHORT MODE
For service, set time can be shortened by short circuit of JPG and JPS the electronic control P.C. board.
The time will be shortened as follows. (Refer to 9-7.)
Set time : 1-minute ➔ 1-second
Set time : 3-minute ➔ 3-second (It takes 3 minutes for the compressor to start operation. However, the starting time is
shortened by short circuit of JPG and JPS.)
No. 1 unit
No. 2 unit
No. 3 unit
No. 4 unit
1 unit operation
No modification
–
–
–
2 units operation
Same as at left
Solder J1
–
–
3 units operation
Same as at left
Same as at left
Solder J2
–
4 units operation
Same as at left
Same as at left
Same as at left
Solder both J1 and J2
Table 1
How to set the remote controller exclusively for particular indoor unit.
After you turn the breaker ON, the first remote controller that sends the signal to the indoor unit will be regarded as the remote
controller for the indoor unit.
The indoor unit will only accept the signal from the remote controller that has been assigned to the indoor unit once they are
set.
The setting will be cancelled if the breaker has turned off, or the power supply has shut down.
Please conduct the above setting once again after the power has restored.
How to modify the remote controller P.C. board
Remove batteries before modification.
The board has a print as shown below :
The P.C. board has the print “J1” and “J2”. Solder “J1” and “J2” according to the number of indoor unit as shown in Table 1.
After modification, press the RESET button.
NOTE : For remodelling, take out
the batteries and press the
OPERATE/STOP(ON/OFF)
button twice or 3 times at
first.
After finish remodelling,
put back the batteries then
press the RESET button.
J2
J1
MSZ-GB50VA
OB454qxp 06.3.22 4:30 PM Page 9

TROUBLESHOOTING
9
10
9-1. Cautions on troubleshooting
1. Before troubleshooting, check the following:
1) Check the power supply voltage.
2) Check the indoor/outdoor connecting wire for mis-wiring.
2. Take care the following during servicing.
1) Before servicing the air conditioner, be sure to turn off the unit first with the remote controller, and then after
confirming the horizontal vane is closed, turn off the breaker and / or disconnect the power plug.
2) Be sure to turn OFF the power supply before removing the front panel, the cabinet, the top panel, and the
electronic control P.C. board.
3) When removing the electronic control P.C. board, hold the edge of the board with care NOT to apply stress on the
components.
4) When connecting or disconnecting the connectors, hold the housing of the connector. DO NOT pull the lead wires.
Housing point
Lead wiring
MSZ-GB50VA
NOTE:
• The operation settings are memorized when 10 seconds have passed after the indoor unit was operated with the
remote controller.
• If main power is turned OFF or a power failure occurs while AUTO START/STOP timer is active, the timer setting is
cancelled.
• If the unit has been off with the remote controller before power failure, the auto restart function does not work as the
power button of the remote controller is off.
• To prevent breaker off due to the rush of starting current, systematize other home appliance not to turn on at the
same time.
• When some air conditioners are connected to the same supply system, if they are operated before power failure,
the starting current of all the compressors may flow simultaneously at restart.
Therefore, the special counter-measures are required to prevent the main voltage-drop or the rush of the starting
current by adding to the system that allows the units to start one by one.
JR07
CN151 CN211CN112 CN1R1
BZ
8-3. AUTO RESTART FUNCTION
When the indoor unit is controlled with the remote controller, the operation mode, the set temperature, and the fan speed
are memorized by the indoor electronic control P.C. board. The “AUTO RESTART FUNCTION” sets to work the moment
power has restored after power failure. Then, the unit will restart automatically.
Operation
1If the main power has been cut, the operation settings remain.
2After the power is restored, the unit restarts automatically according to the memory.
(However, it takes at least 3 minutes for the compressor to start running.)
How to release “AUTO RESTART FUNCTION”
1Turn off the main power for the unit.
2Solder the Jumper wire JR07 on the indoor electronic control P.C. board. (Refer to 9-7.)
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