Mitsubishi Electric MSZ-BT25VG User manual

Models
MSZ-BT20VG -E1 , ER1 , ET1
MSZ-BT25VG -E1 , ER1 , ET1
MSZ-BT35VG -E1 , ER1 , ET1
MSZ-BT50VG -E1 , ER1 , ET1
INDOOR UNIT
Outdoor unit service manual
MUZ-BT∙VG Series (OBH850)
MXZ-F∙VF Series (OBH890)
PARTS CATALOG (OBB849)
CONTENTS
1. TECHNICAL CHANGES ······························2
2. PART NAMES AND FUNCTIONS··················3
3. SPECIFICATION ········································4
4. NOISE CRITERIA CURVES··························5
5. OUTLINES AND DIMENSIONS·····················6
6. WIRING DIAGRAM·····································7
7. REFRIGERANT SYSTEM DIAGRAM ·············8
8. SERVICE FUNCTIONS································9
9. MICROPROCESSOR CONTROL ················ 11
10. TROUBLESHOOTING ······························· 15
11. DISASSEMBLY INSTRUCTIONS················· 28
SERVICE MANUAL
MSZ-BT25VG
No. OBH849
REVISED EDITION-A
OBH849 is void.
Revision A:
• MSZ-BT20/25/35/50VG - ER1 have been
added.

2
Use the specied 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.
TECHNICAL CHANGES
1
MSZ-BT20VG -E1 , ER1 , ET1
MSZ-BT25VG - E1 , ER1 , ET1
MSZ-BT35VG - E1 , ER1 , ET1
MSZ-BT50VG - E1 , ER1 , ET1
1. New model
<Preparation before the repair service>
Prepare the proper tools.
Prepare the proper protectors.
Provide adequate ventilation.
After stopping the operation of the air conditioner, turn off the power-supply breaker and remove the power plug.
Discharge the capacitor before the work involving the electric parts.
<Precautions during the repair service>
Do not perform the work involving the electric parts with wet hands.
Do not pour water into the electric parts.
Do not touch the refrigerant.
Do not touch the hot or cold areas in the refrigeration cycle.
When the repair or the inspection of the circuit needs to be done without turning off the power, exercise great caution not to
touch the live parts.
Revision A:
• MSZ-BT20/25/35/50VG - ER1 have been added.
OBH849A

3
PART NAMES AND FUNCTIONS
2
MSZ-BT20VG MSZ-BT25VG MSZ-BT35VG MSZ-BT50VG
ACCESSORIES
Model
MSZ-BT20VG
MSZ-BT25VG
MSZ-BT35VG
MSZ-BT50VG
Installation plate 1
Installation plate xing screw 4 × 25 mm 5
Wireless remote controller 1
Felt tape (For left or left-rear piping) 1
Battery (AAA) for remote controller 2
Remote controller
Operation indicator lamp
Remote control receiving
section
Spec name plate
Horizontal vane
Air inlet
Air filter
(Air purifying
filter)
Air cleaning filter
(Silver-ionized
air purifier filter,
option)
Front panel
Air outlet
Heat exchanger
Emergency operation switch
OBH849A

4
SPECIFICATION
3
Indoor model MSZ-BT20VG MSZ-BT25VG MSZ-BT35VG MSZ-BT50VG
Power supply Single phase 230 V, 50 Hz
Electrical data
Power input
1
Cooling W19 31
Heating 24 37
Running
current 1
Cooling A0.20 0.31
Heating 0.25 0.35
Fan motor
Model RC0J30-CV
Current 1Cooling A0.20 0.31
Heating 0.25 0.35
Dimensions W × H × D mm 838 × 280 × 235
Weight kg 9.0
Special remarks
Air direction 5
Airow
Cooling
Super High
m3/h
654 792
High 522 660
Med. 408 540
Low 312 456
Super Low 252 378
Heating
Super High 714 846
High 540 714
Med. 408 594
Low 300 468
Super Low 252 360
Sound level
Cooling
Super High
dB(A)
43 46
High 37 38 40
Med. 30 31 36
Low 22 33
Super Low 19 29
Heating
Super High 43 44 48
High 37 43
Med. 30 38
Low 23 33
Super Low 20 29
Fan speed
Cooling
Super High
rpm
990 1,150
High 840 1,000
Med. 700 860
Low 580 760
Super Low 500 660
Heating
Super High 1,060 1,210
High 860 1,060
Med. 700 920
Low 560 770
Super Low 500 640
Fan speed regulator 5
Remote controller model ZH19A
NOTE: Test conditions are based on IS 1391.
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
1 Measured under rated operating frequency.
Specifications and rated conditions of main electric parts
Model MSZ-BT20/25/35/50VG
Fuse (F11) T3.15AL250V
Horizontal vane motor (MV) 12 V DC
Varistor
(NR11) 470 V
Terminal block (TB) 3P
OBH849A

5
NOISE CRITERIA CURVES
4
MSZ-BT25VG
MSZ-BT35VG MSZ-BT50VG
10
20
30
40
50
60
70
80
90
63 125 250 500 1000 2000 4000 8000
OCTAVE BAND SOUND PRESSURE LEVEL,dB re 0.0002 MICRO BAR
BAND CENTER FREQUENCIES,Hz
NC-60
NC-50
NC-40
NC-30
NC-20
NC-70
COOLING
FUNCTION SPL(dB(A)) LINE
46
HEATING 44
10
20
30
40
50
60
70
80
90
63 125 250 500 1000 2000 4000 8000
NC-60
NC-50
NC-40
NC-30
NC-20
NC-70
OCTAVE BAND SOUND PRESSURE LEVEL,dB re 0.0002 MICRO BAR
BAND CENTER FREQUENCIES,Hz
COOLING
FUNCTION SPL(dB(A)) LINE
46
HEATING 48
10
20
30
40
50
60
70
80
90
63 125 250 500 1000 2000 4000 8000
NC-60
NC-50
NC-40
NC-30
NC-20
NC-70
OCTAVE BAND SOUND PRESSURE LEVEL,dB re 0.0002 MICRO BAR
BAND CENTER FREQUENCIES,Hz
COOLING
FUNCTION SPL(dB(A)) LINE
43
HEATING 43
Test conditions
Cooling: Dry-bulb temperature 27°C
Wet-bulb temperature 19°C
Heating: Dry-bulb temperature 20°C
Wet-bulb temperature 15°C
INDOOR UNIT
WALL
MICROPHONE
0.8m
1m
MSZ-BT20VG
10
20
30
40
50
60
70
80
90
63 125 250 500 1000 2000 4000 8000
NC-60
NC-50
NC-40
NC-30
NC-20
NC-70
OCTAVE BAND SOUND PRESSURE LEVEL,dB re 0.0002 MICRO BAR
BAND CENTER FREQUENCIES,Hz
COOLING
FUNCTION SPL(dB(A)) LINE
43
HEATING 43
OBH849A

6
OUTLINES AND DIMENSIONS
5
MSZ-BT20VG MSZ-BT25VG MSZ-BT35VG MSZ-BT50VG Unit: mm
100.5
242.5
225 225
199.537.5
100.5
52.5
167.5 167.5
366.5 327.5 91.5
3
37.5 199.5
219.5
242.5
23.5
46 18.5
167
838
235 5
280
50
(5) 351.5
66.5 2.5
64
43
57
42
57
164
100
12.5
126.5
98
40
57
677.5 111(49.5)
MIN 37mm
IN CASE OF LEFT, LEFT REAR,OR LEFT UNDER PIPING (USING SPACER), MIN 125mm
MIN 20mm
MIN 7mm
MIN 30mm
INSTALLATION PLATE 11×20 OBLONG HOLE
11×26 OBLONG HOLE
INDOOR UNIT
WALL HOLE
ø 65
AIR OUT
AIR IN INSTALLATION PLATE
PIPING
DRAIN HOSE
MSZ-BT20/25/35VG
PIPING
INSULATION ø37 O.D
LIQUID LINE ø6.35 - 0.39m
(FLARED CONNECTION ø6.35)
GAS LINE ø9.52 - 0.34m
(FLARED CONNECTION ø9.52)
DRAIN HOSE INSULATION ø29
CONNECTED PART ø16 O.D
MSZ-BT50VG
PIPING
INSULATION ø37 O.D
LIQUID LINE ø6.35 - 0.39m
(FLARED CONNECTION ø6.35)
GAS LINE ø9.52 - 0.34m
(FLARED CONNECTION ø12.7)
DRAIN HOSE INSULATION ø29
CONNECTED PART ø16 O.D
OBH849A

7
MSZ-BT20VG- E1 ,ER1 MSZ-BT25VG- E1 ,ER1 MSZ-BT35VG- E1 ,ER1 MSZ-BT50VG- E1 ,ER1
WIRING DIAGRAM
6
MSZ-BT20VG- ET1 MSZ-BT25VG- ET1 MSZ-BT35VG- ET1 MSZ-BT50VG- ET1
UZAKTAN KUMANDA
ALICI DEVRE KARTI
İÇ ÜNİTE TERMİNAL
KARTI
DIŞ ÜNİTEYE
VARİSTÖR
TERMİNAL BLOĞU
RESİSTÖR
İÇ ÜNİTE ELEKTRONİK
KONTROL KARTI
Konektör
Terminal bloğu
NOTLAR:
1. Dış ünite elektronik kablolaması için dış ünite
elektronik kablo devre şemasını referans alınız.
2. Sadece bakır besleme kablosu kullanın
3. Sembolleri gösterir
ODA SICAKLIK
TERMİSTÖRÜ
BORU SICAKLIK
TERMİSTÖRÜ
(ANA)
BORU SICAKLIK
TERMİSTÖRÜ
(YARDIMCI)
SİGORTA
(T3.15AL250V)
FAN MOTORU
KANAT MOTORU
(YATAY)
RÖLE
PARÇA ADI
OBH849A

8
REFRIGERANT SYSTEM DIAGRAM
7
Unit: mm
MSZ-BT20VG MSZ-BT25VG
Indoor
heat
exchanger
Flared connection
Room temperature
thermistor
RT11 Flared connection
Refrigerant pipe ø9.52
(with heat insulator)
Refrigerant pipe ø6.35
(with heat insulator)
Indoor coil
thermistor
RT12
Indoor coil
thermistor
RT13
Refrigerant flow in cooling
Refrigerant flow in heating
MSZ-BT35VG MSZ-BT50VG
Indoor
heat
exchanger
Flared connection
Room temperature
thermistor
RT11
Flared connection
Refrigerant pipe ø6.35
(with heat insulator)
Indoor coil
thermistor
RT12
Refrigerant pipe ø 9.52 (MSZ-BT35VG)
ø12.7 (MSZ-BT50VG)
(with heat insulator)
Indoor coil
thermistor
RT13
Refrigerant flow in cooling
Refrigerant flow in heating
OBH849A

9
MSZ-BT20VG MSZ-BT25VG MSZ-BT35VG MSZ-BT50VG
8-1. TIMER SHORT MODE
For service, the following set time can be shortened by bridging the timer short mode point on the electronic control P.C.
board. (Refer to 10-7.)
• The set time for the ON/OFF timer can be reduced to 1 second for each minute.
• After the breaker is turned on, the time for starting the compressor, which normally takes 3 minutes, can be reduced to 1
minute. Restarting the compressor, which takes 3 minutes, cannot be reduced.
SERVICE FUNCTIONS
8
8-2. HOW TO SET REMOTE CONTROLLER EXCLUSIVELY FOR A PARTICULAR INDOOR UNIT
A maximum of 4 indoor units with wireless remote controllers can be set.
To operate the indoor unit individually with each remote controller, assign a number to each remote controller according
to the number of the indoor unit.
Set according to the following procedure:
(1) Turn the breaker OFF for the unit.
(2) With the remote controller powered OFF, hold down UNIT button on the remote controller for 2 seconds to
enter the pairing mode.
Setting number is displayed in the remote controller.
(3) Press UNIT button again and assign a number to each remote controller.
Each press of UNIT button advances the number in the following order: 1→2→3→4.
(4) Press to OPERATION SELECT( ) button complete the pairing setting.
After you turn the breaker ON, the remote controller that first sends a signal to an indoor unit will be regarded as the
remote controller for the indoor unit.
Once they are set, the indoor unit will only receive the signal from the assigned remote controller afterwards.
The setting of indoor unit will be cancelled, if the breaker is turned OFF or the power supply is shut down.
OBH849A

10
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. “AUTO RESTART FUNCTION” automatically starts operation in
the same mode just before the shutoff of the main power.
Operation
If the main power has been cut, the operation settings remain.
After 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 disable “AUTO RESTART FUNCTION”
Turn off the main power for the unit.
Cut the jumper wire to JR77 on the indoor electronic control P.C. board. (Refer to 10-7.)
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 can-
celled.
• If the unit has been turned 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 the breaker from tripping 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.
JR77
Indoor electronic
control P.C. board
CN 111 CN151
GND
CN112
OBH849A