Mitsubishi Electric MSZ-AP15VG-E1 User manual

INDOOR UNIT
SERVICE MANUAL
Outdoor unit service manual
MUZ-AP∙VG Series (OBH839)
MXZ-D∙VA Series (OBH626)
MXZ-E∙VA Series (OBH723)
MXZ-F∙VF Series (OBH790)
PARTS CATALOG (OBB838)
MSZ-AP15VG
MSZ-AP20VG
CONTENTS
1. TECHNICAL CHANGES ······························3
2. PART NAMES AND FUNCTIONS ··················4
3. SPECIFICATION ········································5
4. NOISE CRITERIA CURVES··························6
5. OUTLINES AND DIMENSIONS·····················7
6. WIRING DIAGRAM ·····································8
7. REFRIGERANT SYSTEM DIAGRAM ··········· 11
8. SERVICE FUNCTIONS······························ 12
9. MICROPROCESSOR CONTROL ················ 14
10. TROUBLESHOOTING ······························· 21
11. DISASSEMBLY INSTRUCTIONS················· 35
Models
MSZ-AP15VG -E1 , ET1 , ER1 , E2 , ET2
MSZ-AP20VG -E1 , ET1 , ER1 , E2 , ET2
MSZ-AP15VGK -E1 , ET1 , ER1
MSZ-AP20VGK -E1 , ET1 , ER1
OBH838 REVISED EDITION-A is void.
Revision B:
• MSZ-AP15/20VG- E2 , ET2 and
MSZ-AP15/20VGK- E1 , ET1 , ER1 have
been added.
No. OBH838
REVISED EDITION-B

2
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.
<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-AP15/20VG- ER1 have been added.
Revision B:
• MSZ-AP15/20VG- E2 , ET2 and MSZ-AP15/20VGK- E1 , ET1 , ER1 have been added.
OBH838B

3
TECHNICAL CHANGES
1
MSZ-AP15VG - E1 , ET1 , ER1
MSZ-AP20VG - E1 , ET1 , ER1
MSZ-AP15VGK - E1 , ET1 , ER1
MSZ-AP20VGK - E1 , ET1 , ER1
1. New model
MSZ-AP15VG - E1 , ET1 MSZ-AP15VG - E2 , ET2
MSZ-AP20VG - E1 , ET1 MSZ-AP20VG - E2 , ET2
1. Remote controller has been changed.
These models are compatible with the outdoor units with low standby power control.
Connecting these models to the MUZ-AP·VG series outdoor units enables the low standby power control.
These models may be connected to the MUZ-AP·VG series after once connected to the MXZ series and operated, for exam-
ple because of relocation. In that case, the MUZ-AP·VG series outdoor units will not operate without taking a step. Follow the
procedure "Deleting the memorized abnormal condition" described in 10-2.1.
OBH838B

4
ACCESSORIES
(1) Installation plate 1
(2) Installation plate xing screw 4 × 25 mm 5
(3) Wireless remote controller 1
(4) Felt tape (For left or left-rear piping) 1
(5) Battery (AAA) for (3) 2
MSZ-AP15VG MSZ-AP15VGK MSZ-AP20VG MSZ-AP20VGK
PART NAMES AND FUNCTIONS
2
Remote controller
Operation
indicator lamp
Remote control
receiving section
Horizontal vane
Air outlet
Air filter
Heat exchanger Emergency
operation switch
Front panel
Spec name plate
Wi-Fi interface
Air inlet
MSZ-AP·VGK
OBH838B

5
Indoor model MSZ-AP15VG
MSZ-AP15VGK
MSZ-AP20VG
MSZ-AP20VGK
Power supply Single phase 230 V, 50 Hz
Electrical data
Power
input *1
Cooling W17 19
Heating 17 19
Running
current *1
Cooling A0.17 0.19
Heating 0.17 0.19
Fan motor
Model RC0J30-CW
Current *1 Cooling A0.17 0.19
Heating 0.17 0.19
Dimensions W × H × D mm 760 × 250 × 178
Weight kg 8.2
Special remarks
Air direction 5
Airow
Cooling
Super High
m3/h
384 414
High 330 330
Med. 276 276
Low 234 234
Silent 210
Heating
Super High
m3/h
408 438
High 360
Med. 300
Low 264
Silent 222
Sound level
Cooling
Super High
dB(A)
40 42
High 35
Med. 30
Low 26
Silent 21
Heating
Super High
dB(A)
40 42
High 35
Med. 30
Low 26
Silent 21
Fan speed
Cooling
Super High
rpm
1,430 1,530
High 1,250 1,250
Med. 1,080 1,080
Low 940 940
Silent 860
Heating
Super High
rpm
1,430 1,530
High 1,290
Med. 1,110
Low 990
Silent 870
Fan speed regulator 5
Remote
controller model
VG - E1 ,ET1 ,ER1 SG19C
Others SH20B
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
Heating: Indoor Dry-bulb temperature 20°C
Outdoor Dry-bulb temperature 7°C Wet-bulb temperature 6°C
*1 Measured under rated operating frequency.
Specifications and rating conditions of main electric parts
Fuse (F11) T3.15AL250V
Horizontal vane motor (MV) 12 V DC
Varistor (NR11) 470 V
Terminal block (TB) 3P
SPECIFICATION
3
OBH838B

6
MSZ-AP15VG MSZ-AP15VGK
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
OCTAVE BAND SOUND PRESSURE LEVEL, dB re 0.0002 MICRO BAR
BAND CENTER FREQUENCIES, Hz
COOLING
FUNCTION SPL(dB(A)) LINE
Super High
FAN SPEED
HEATING
42
42
NC-10
MSZ-AP20VG MSZ-AP20VGK
Test conditions
Cooling: Dry-bulb temperature 27°C
Wet-bulb temperature 19°C
Heating: Dry-bulb temperature 20°C
INDOOR UNIT
WALL
MICROPHONE
0.8m
1m
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
OCTAVE BAND SOUND PRESSURE LEVEL, dB re 0.0002 MICRO BAR
BAND CENTER FREQUENCIES, Hz
COOLING
FUNCTION SPL(dB(A)) LINE
Super High
FAN SPEED
HEATING
40
40
NC-10
NOISE CRITERIA CURVES
4
OBH838B

7
Unit: mm
MSZ-AP15VG MSZ-AP15VGK MSZ-AP20VG MSZ-AP20VGK
OUTLINES AND DIMENSIONS
5
Piping
Insulation ø35 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
193
60 19
155295
167.5
187.5
209
21.5
41
3
299.5
145145
335
(45)
166.5
208
61 78
42
740
760
178
5
250
335.5
14.551
100
11
96
166
80.5
50
10
(66) 505 189
INDOOR UNIT
INSTALLATION PLATE
11×26 OBLONG HOLE 11×20 OBLONG HOLE
WALL HOLE
ø 65
IN CASE OF LEFT, LEFT BACK,OR LEFT UNDER PIPING (USING SPACER), MIN 120.5mm
MIN 44.5mm
MIN 14mm
MIN 30mm
MIN 20mm
AIR IN
PIPING
DRAIN HOSE
INSTALLATION PLATE
AIR OUT
OBH838B

8
MSZ-AP15VG - E1 , ER1 MSZ-AP20VG - E1 , ER1
MSZ-AP15VG - ET1 MSZ-AP20VG - ET1
WIRING DIAGRAM
6
ALICI KARTI
SİVİÇ KARTI GÖSTERGE KARTI
RÖLE
İÇ ÜNİTE ELEKTRONİK
KONTROL KARTI
3. Sembolleri gösterir
2. Sadece bakır besleme kablosu kullanın
NOTLAR
:
1. Dış ünite elektronik kablolaması için dış ünite
elektronik kablo devre şemasını referans alınız.
SİGORTA
(T3.15AL250V)
FAN MOTORU
VARİSTÖR
ODA SICAKLIK
TERMİSTÖRÜ
BORU SICAKLIK
TERMİSTÖRÜ(ANA)
BORU SICAKLIK
TERMİSTÖRÜ(YARDIMCI)
DIŞ ÜNİTEYE
Terminal bloğu
Konektör
PARÇA ADI
TERMİNAL BLOĞU
SEMBOL SEMBOL
KANAT MOTORU
(YATAY ÜST)
KANAT MOTORU
(YATAY ALT)
RESİSTÖR
PARÇA ADI
OBH838B

9
MSZ-AP15VG - E2 MSZ-AP20VG - E2
MSZ-AP15VG - ET2 MSZ-AP20VG - ET2
DIŞ
ÜNİTEYE
İÇ ÜNİTE ELEKTRONİK
KONTROL KARTI
SİVİÇ
KARTI GÖSTERGE
KARTI ALICI
KARTI
PARÇA ADI SEMBOL PARÇA ADISEMBOL
RÖLE
SİGORTA
(T3.15AL250V)
FAN MOTORU
KANAT MOTORU
(YATAY ÜST)
KANAT MOTORU
(YATAY ALT)
RESİSTÖR
ODA SICAKLIK
TERMİSTÖRÜ
BORU SICAKLIK
TERMİSTÖRÜ(ANA)
BORU SICAKLIK
TERMİSTÖRÜ(YARDIMCI)
TERMİNAL 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 Terminal bloğu
Konektör
Detaylar için SERVİS KILAVUZUNA bakınız
Arıza durumunun detaylı çözümü için arıza geri
çağırma fonksiyonu ile kontrol ediniz.
Arıza geri çağırma fonksiyonu için SERVİS MANUELİNE bakınız
VARİSTÖR
OBH838B

10
MSZ-AP15VGK - E1 , ER1 MSZ-AP20VGK - E1 , ER1
MSZ-AP15VGK - ET1 MSZ-AP20VGK - ET1
DIŞ
ÜNİTEYE
İÇ ÜNİTE ELEKTRONİK
KONTROL KARTI
SİVİÇ
KARTI GÖSTERGE
KARTI ALICI
KARTI
PARÇA ADI SEMBOL PARÇA ADISEMBOL
RÖLE
SİGORTA
(T3.15AL250V)
FAN MOTORU
KANAT MOTORU
(YATAY ÜST)
KANAT MOTORU
(YATAY ALT)
RESİSTÖR
ODA SICAKLIK
TERMİSTÖRÜ
BORU SICAKLIK
TERMİSTÖRÜ(ANA)
BORU SICAKLIK
TERMİSTÖRÜ(YARDIMCI)
TERMİNAL 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 Terminal bloğu
Konektör
Detaylar için SERVİS KILAVUZUNA bakınız
Arıza durumunun detaylı çözümü için arıza geri
çağırma fonksiyonu ile kontrol ediniz.
Arıza geri çağırma fonksiyonu için SERVİS MANUELİNE bakınız
Wİ-Fİ
ARAYÜZÜ
VARİSTÖR
OBH838B

11
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 (main)
Indoor coil
thermistor
RT13 (sub)
Refrigerant flow in cooling
Refrigerant flow in heating
Unit: mm
MSZ-AP15VG MSZ-AP15VGK MSZ-AP20VG MSZ-AP20VGK
REFRIGERANT SYSTEM DIAGRAM
7
OBH838B

12
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 3
seconds. Restarting the compressor, which takes 3 minutes, cannot be reduced.
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 used in a room.
To operate the indoor units individually with each remote controller, assign a number to each remote controller according
to the number of the indoor unit.
This setting can be set only when all the following conditions are met:
• The remote controller is powered OFF.
• Weekly timer is not set.
• Weekly timer is not being edited.
(1) Hold down button on the remote controller for 2 seconds to enter the pairing mode.
(2) Press button again and assign a number to each remote controller.
Each press of button advances the number in the following order: 1 → 2 → 3 → 4.
(3) Press button to complete the pairing setting.
MSZ-AP15VG MSZ-AP15VGK MSZ-AP20VG MSZ-AP20VGK
SERVICE FUNCTIONS
8
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 has 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 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 start-
ing 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.
CN112
R111
Indoor electronic
control P.C. board
JR77
IC112
CN151
CN111
CN211
OBH838B

13
8-4. Wi-Fi INTERFACE SETTING UP (MSZ-AP·VGK)
ERR
NET
MODE
UNIT
RESET MODE
Wi-Fi INTERFACE
MODEL
XXXXXXXX
MAC
ID
SSID
KEY
: XXXXXXXXXXXX
: XXXXXXXXXX
: XXXXXXXXXXXX
: XXXXXXXXXXXX
VOLTAGE
CURRENT
:
:
MITSUBISHI ELECTRIC CORPRATION
WiFi.ASSY DWG No.
XXXXXXXXXXX
MADE IN CHINA
XXXXXXXXXX
>PP<
3
4
5
6
1
2
This Wi-Fi interface communicates the status information and controls
the commands from the MELCloud by connecting to an indoor unit.
(1) MODE switch
• The MODE switch is used for selecting modes in configurations.
(2) RESET switch
• Hold down the RESET switch for 2 seconds to reboot the system.
• Hold down the RESET switch for 14 seconds to initialize the Wi-Fi interface to
the factory default.
(1) Open the front panel and the Wi-Fi cover.
(2) Set up a connection between the Wi-Fi interface and the router.
Refer to the SETUP MANUAL and SETUP QUICK
REFERENCE GUIDE provided with the unit.
For SETUP MANUAL, please go to the website below.
https://www.melcloud.com/Support
(3) Close the Wi-Fi cover and the front panel after the setup
is completed.
(4) For MELCloud User Manual, please go to the website below.
https://www.melcloud.com/Support
NOTE:
Mitsubishi Electric’s Wi-Fi interface is designed for communication to Mit-
subishi Electric’s MELCloud Wi-Fi service.
Third party Wi-Fi interfaces cannot be connected to MELCloud.
Mitsubishi Electric is not responsible for any (i) under performance of a sys-
tem or any product; (ii) system or product fault; or (iii) loss or damage to any
system or product; which is caused by or arises from connection to and/or use
of any third party Wi-Fi interface or any third party Wi-Fi service with Mitsubishi
Electric equipment.
For the latest information regarding MELCloud from Mitsubishi Electric
Corporation, please visit www.MELCloud.com.
NOTE:
When the Wi-Fi interface is reset to the factory default, ALL the configuration
information will be lost. Take great care in implementing this operation.
No. Item Description
1 MODE switch It selects modes.
2 RESET switch It resets the system and ALL settings.
3 ERR LED (Orange) It shows the network error state.
4 NET LED (Green) It shows the network state.
5 MODE LED (Orange) It shows the Access point mode state.
6 UNIT LED (Green) It shows the indoor unit state.
Wi-Fi interface introduction
• Ensure that the Router supports the WPA2-AES encryption setting before
starting the Wi-Fi interface setup.
• The End user should read and accept the terms and conditions of the Wi-Fi
service before using this Wi-Fi interface.
• To complete connection of this Wi-Fi interface to the Wi-Fi service, the Rout-
er may be required.
• This Wi-Fi interface will not commence transmission of any operational data
from the system until the End user registers and accepts the terms and con-
ditions of the Wi-Fi service.
• This Wi-Fi interface should not be installed and connected to any Mitsubishi
Electric system which is to provide application critical cooling or heating.
• At the time of relocation or disposal, reset the Wi-Fi interface to the factory
default.
Wi-Fi interface
Front panel
Front panel
Wi-Fi cover
OBH838B

14
WIRELESS REMOTE CONTROLLER
NOTE: Last setting will be stored after the unit is turned OFF with the remote controller. Indoor unit receives the signal of the
remote controller with beeps.
MICROPROCESSOR CONTROL
9
MSZ-AP15VG MSZ-AP15VGK MSZ-AP20VG MSZ-AP20VGK
Signal transmitting section
Operation display section
(Backlight display)
Battery replacement indicator
Temperature buttons
OFF/ON
(stop/operate) button
Distance of signal :
About 6 m
Beep(s) is (are) heard
from the indoor unit
when the signal is received
FAN speed control button
Operation select button
ECONO COOL button
CLOCK button
TIME, WEEKLY TIMER
set buttons
TIME, TIMER set buttons
Increase time
Decrease time
RESET button
i save button
VANE control button
NIGHT MODE button
Lid
Slide the lid down to open
the remote controller. Slide
it down further to get to the
weekly timer buttons.
Operation Indicator lamp
The operation indicator at the right side of the indoor unit indicates the operation state.
•The following indication applies regardless of shape of the indication.
Indication Operation state Room temperature
The unit is operating to
reach the set temperature About 2°C or more away from set temperature
The room temperature is approaching the set tem-
perature
About 1 to 2°C from set
temperature
Standby mode (Only during multi system
operation)
-
INDOOR UNIT DISPLAY SECTION
Lit
Blinking
Not lit
OBH838B

15
9-1. COOL ( ) OPERATION
(1) Press OFF/ON(stop/operate) button.
OPERATION INDICATOR lamp of the indoor unit turns on with a beep tone.
(2) Select COOL mode with Operation select button.
(3) Press Temperature buttons (TEMP or button) to select the desired temperature. The setting range is 16 - 31°C.
1. Coil frost prevention
The compressor operational frequency is controlled by the temperature of the indoor heat exchanger to prevent the coil
from frosting.
When the temperature of indoor heat exchanger becomes too low, the coil frost prevention mode works.
The indoor fan operates at the set speed and the compressor stops. This mode continues until the temperature of indoor
heat exchanger rises.
2. Low outside temperature operation
When the outside temperature is lower, low outside temperature operation starts, and the outdoor fan slows or stops.
9-2. DRY ( ) OPERATION
(1) Press OFF/ON(stop/operate) button.
OPERATION INDICATOR lamp of the indoor unit turns on with a beep tone.
(2) Select DRY mode with Operation select button.
(3) The set temperature is determined from the initial room temperature.
1. Coil frost prevention
Coil frost prevention works the same way as that in COOL mode. (9-1.1.)
2. Low outside temperature operation
Low outside temperature operation works the same way as that in COOL mode. (9-1.2.)
9-3. FAN ( ) OPERATION
(1) OPERATION INDICATOR lamp of the indoor unit turns on with a beep tone.
(2) Select FAN mode with Operation select button.
(3) Select the desired fan speed. When AUTO, it becomes Low.
Only indoor fan operates.
Outdoor unit does not operate.
9-4. HEAT ( ) OPERATION
(1) Press OFF/ON(stop/operate) button.
OPERATION INDICATOR lamp of the indoor unit turns on with a beep tone.
(2) Select HEAT mode with Operation select button.
(3) Press Temperature buttons (TEMP or button) to select the desired temperature. The setting range is 10 - 31°C.
1. Cold air prevention control
When the compressor is not operating or is starting, and the temperature of indoor heat exchanger and/or the room tem-
perature is low or when defrosting is being done, the indoor fan will stop or rotate in Very Low speed.
2. High pressure protection
The compressor operational frequency is controlled by the temperature of the indoor heat exchanger to prevent the con-
densing pressure from increasing excessively.
When the temperature of indoor heat exchanger becomes too high, the high pressure protection works.
The indoor fan operates following the cold air prevention control. This mode continues until the temperature of indoor
heat exchanger falls.
3. Defrosting
Defrosting starts when the temperature of outdoor heat exchanger becomes too low.
The compressor stops once, the indoor/outdoor fans stop, the 4-way valve reverses, and the compressor re-starts.
This mode continues until the temperature of outdoor heat exchanger rises or the fixed time passes.
OBH838B

16
9-5. AUTO CHANGE OVER ∙∙∙ AUTO MODE OPERATION
Once desired temperature is set, unit operation is switched automatically between COOL and HEAT operation.
Mode selection
(1) Initial mode
When unit starts the operation with AUTO operation from OFF:
• If the room temperature is higher than the set temperature, operation starts in COOL mode.
• If the room temperature is equal to or lower than the set temperature, operation starts in HEAT mode.
(2) Mode change
COOL mode changes to HEAT mode when about 15 minutes has passed with the room temperature 1°C below the set
temperature.
HEAT mode changes to COOL mode when about 15 minutes has passed with the room temperature 1°C above the set
temperature.
NOTE 1
If 2 or more indoor units are operating in multi system, there might be a case that the indoor unit, which is operating in (AUTO),
cannot change over to the other operating mode (COOL ↔ HEAT) and becomes a state of standby.
Refer to NOTE 2 “FOR MULTI SYSTEM AIR CONDITIONER”.
NOTE 2
FOR MULTI SYSTEM AIR CONDITIONER OUTDOOR UNIT: MXZ series
Multi system air conditioner can connect 2 or more indoor units with one outdoor unit.
• When you try to operate 2 or more indoor units with one outdoor unit simultaneously, one for the cooling and the others for
heating, the operation mode of the indoor unit that operates first is selected. Other indoor units cannot operate, and operation
indicator lamp blinks as shown in the figure below. In this case, please set all the indoor units to the same operation mode.
• When indoor unit starts the operation while the defrosting of outdoor unit is being done, it takes a few minutes (max. 10 min-
utes) to blow out the warm air.
• In HEAT operation, though indoor unit that does not operate may get warm or the sound of refrigerant flowing may be heard,
they are not malfunction. The reason is that the refrigerant continuously flows into it.
OPERATION INDICATOR
Lit
Blinking
Not lit
9-6. AUTO VANE OPERATION
1. Horizontal vane
(1) Vane motor drive
These models are equipped with a stepping motor for the horizontal vane. The rotating direction, speed, and angle of
the motor are controlled by pulse signals (approximately 12 V) transmitted from indoor microprocessor.
(2) The horizontal vane angle and mode change as follows by pressing VANE control button.
(3) Positioning
To confirm the standard position, the vane moves until it touches the vane stopper. Then the vane is set to the
selected angle.
Confirming of standard position is performed in the following cases:
(a) When the operation starts or finishes (including timer operation).
(b) When the test run starts.
(c) When standby mode (only during multi system operation) starts or finishes.
(4) VANE AUTO ( ) mode
In VANE AUTO mode, the microprocessor automatically determines the vane angle to make the optimum room tem-
perature distribution.
Horizontal
position
4
In COOL and DRY operation
Vane angle is fixed to Horizontal position.
In HEAT operation
Vane angle is fixed to Angle 4.
AUTO 1 2 3 4 5 SWING
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(5) STOP (operation OFF) and ON TIMER standby
In the following cases, the horizontal vane returns to the closed position.
(a) When OFF/ON(stop/operate) button is pressed (POWER OFF).
(b) When the operation is stopped by the emergency operation.
(c) When ON TIMER is ON standby.
(6) Dew prevention
During COOL or DRY operation with the vane angle at Angle 4 or 5 when the compressor cumulative operation time
exceeds 1 hour, the vane angle automatically changes to Angle 1 for dew prevention.
(7) SWING ( ) mode
By selecting SWING mode with VANE control button, the horizontal vane swings vertically.
(8) Cold air prevention in HEAT operation
The horizontal vane position is set to Upward.
NOTE: When 2 or more indoor units are operated with multi outdoor unit, even if any indoor unit turns thermostat off,
this control does not work in the indoor unit.
(9) ECONO COOL ( ) operation (ECONOmical operation)
When ECONO COOL button is pressed in COOL mode, set temperature is automatically set 2°C higher by the
microprocessor. However, the temperature on the LCD screen on the remote controller is not changed.
Also the horizontal vane swings in various cycle.
SWING operation makes you feel cooler than set temperature. So, even though the set temperature is higher, the
air conditioner can keep comfort. As a result, energy can be saved.
To cancel this operation, select a different mode or press one of the following buttons in ECONO COOL operation:
ECONO COOL, VANE control button.
9-7. TIMER OPERATION
1. How to set the time
(1) Check that the current time is set correctly.
NOTE: Timer operation will not work without setting the current time. Initially “0:00” blinks at the current time display
of TIME MONITOR, so set the current time correctly with CLOCK button.
How to set the current time
(a) Press the CLOCK button.
(b) Press the TIME set buttons ( and ) to set the current time.
• Each time Increase time button ( ) is pressed, the set time increases by 1 minute, and each time Decrease
time button ( ) is pressed, the set time decreases by 1 minute.
• Pressing those buttons longer, the set time increases/decreases by 10 minutes.
(c) Press the CLOCK button.
(2) Press OFF/ON(stop/operate) button to start the air conditioner.
(3) Set the time of timer.
ON timer setting
(a) Press ON TIMER button( ) during operation.
(b) Set the time of the timer using TIME set buttons ( and ).*
OFF timer setting
(a) Press OFF TIMER button ( ) during operation.
(b) Set the time of the timer using TIME set buttons ( and ).*
* Each time Increase time button ( ) is pressed, the set time increases by 10 minutes: each time Decrease time
button ( ) is pressed, the set time decreases by 10 minutes.
2. To release the timer
To release ON timer, press ON TIMER button ( ).
To release OFF timer, press OFF TIMER button( ).
TIMER is cancelled and the display of set time disappears.
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(Example 1) The current time is 8:00 PM.
The unit turns off at 11:00 PM, and on at 6:00 AM.
• OFF timer and ON timer can be used in combination. The set time that is reached first will operate first.
• “ ” and “ ” display shows the order of OFF timer and ON timer operation.
PROGRAM TIMER
(Example 2) The current time is 11:00 AM.
The unit turns on at 5:00 PM, and off at 9:00 PM.
NOTE: If the main power is turned OFF or a power failure occurs while ON/OFF timer is active, the timer setting is can-
celled. As these models are equipped with an auto restart function, the air conditioner starts operating with timer
cancelled when power is restored.
9-8. WEEKLY TIMER OPERATION
• A maximum of 4 ON or OFF timers can be set for individual days of the week.
• A maximum of 28 ON or OFF timers can be set for a week.
NOTE:
• The simple ON/OFF timer setting is available while the weekly timer is on. In this case, the ON/OFF timer has priority over the
weekly timer; the weekly timer operation will start again after the simple ON/OFF timer is complete.
• When the weekly timer is set, temperature cannot be set to 10°C.
• The weekly timer operation and i-save operation cannot be used together.
* Make sure that the current time and day are set correctly.
(1) Press button to enter the weekly timer setting mode.
(2) Press and buttons to select setting day and number.
* blinks.
Pressing selects the day of
the week to be set.
Pressing selects
the setting number.
E.g. : [Mon Tue ... Sun]
and [1] are selected.
* All days can be selected.
1. How to set the weekly timer
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(3) Press , , and buttons to set ON/OFF, time, and temperature.
E.g. : [ON], [6:00]
and [24°C] are
selected.
Pressing
selects ON/OFF timer.
Pressing
deletes timer setting.
Pressing
adjusts the time.
Pressing
adjusts the tem-
perature.
* Hold down the button to change the time quickly.
Press and buttons to continue setting the timer for other days and/or numbers.
(4) Press button to complete and transmit the weekly timer setting.
* which was blink-
ing goes out, and the
current time will be
displayed.
NOTE:
• Press button to transmit the setting information of weekly timer to the indoor unit. Point the remote controller toward the
indoor unit for 3 seconds.
• When setting the timer for more than one day of the week or one number, button does not have to be pressed per each
setting. Press button once after all the settings are complete. All the weekly timer settings will be saved.
• Press button to enter the weekly timer setting mode, and press and hold button for 5 seconds to erase all weekly
timer settings. Point the remote controller toward the indoor unit.
(5) Press button to turn the weekly timer ON. ( lights.)
•When the weekly timer is ON, the day of the week whose timer setting is complete, will light.
Press button again to turn the weekly timer OFF. ( goes out.)
NOTE:
The saved settings will not be cleared when the weekly timer is turned OFF.
2. Checking weekly timer setting
(1) Press button to enter the weekly timer setting mode.
* blinks.
(2) Press or buttons to view the setting of the particular day or number.
(3) Press button to exit the weekly timer setting.
NOTE:
When all days of the week are selected to view the settings and a di󰀨erent setting is included among them, will be
displayed.
9-9. NIGHT MODE ( ) OPERATION
NIGHT MODE changes the brightness of the operation indicator, disables the beep sound and limits the noise level of the
outdoor unit.
(1) Press NIGHT MODE button during operation to activate NIGHT MODE ( ).
• The operation indicator lamp dims.
• The beep sound will be disabled except that emitted when the operation is started or stopped.
• Noise level of the outdoor unit will be lower than that mentioned in SPECIFICATIONS.(Except the connection to MXZ.)
(2) Press NIGHT MODE button to cancel NIGHT MODE ( ).
NOTE:
•The cooling / heating capacity may drop.
•Noise level of the outdoor unit may not change after startup of the unit, during the protection operation, or depending on
other operating conditions.
•The fan speed of the indoor unit will not change.
•The operation indicator lamp will be hard to be seen in a bright room.
•Noise level of the outdoor unit will not decrease during Multi system operation.
•Operating POWERFUL operation during NIGHT MODE operation will increase the noise level of the outdoor unit.
•Noise level of the outdoor unit will not decrease during Multi system operation.
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9-11. EMERGENCY/TEST OPERATION
In the case of test run operation or emergency operation, use the
emergency operation switch on the right side of the indoor unit.
Emergency operation is available when the remote controller is miss-
ing or has failed, or when the batteries in the remote controller are
running down. The unit will start and OPERATION INDICATOR lamp
will light up.
The first 30 minutes of operation is the test run operation. This opera-
tion is for servicing. The indoor fan runs at High speed and the tem-
perature control does not work. After 30 minutes of test run operation,
the system shifts to EMERGENCY COOL/HEAT MODE with a set tem-
perature of 24°C. The fan speed shifts to Med. The coil frost preven-
tion works even in the test run or the emergency operation. In the test
run or emergency operation, the horizontal vane operates in VANE
AUTO ( ) mode. Emergency operation continues until the emergency
operation switch is pressed once or twice or the unit receives any sig-
nal from the remote controller. In the latter case, normal operation will
start.
NOTE: Do not press the emergency operation switch during normal operation.
Operation mode COOL/HEAT
Set temperature 24°C
Fan speed Medium
Horizontal vane Auto
The operation mode is indicated by the
Operation Indicator lamp as following
Operation Indicator lamp
EMERGENCY COOL
↓
EMERGENCY HEAT
↓
STOP
Lit
Not lit
9-10. i-save ( ) OPERATION
1. How to set i-save operation
(1) Press OFF/ON(stop/operate) button.
(2) Select COOL, HEAT, ECONO COOL or NIGHT MODE.
(3) Press i-save button.
(4) Set the temperature, fan speed, and airow direction for i-save operation.
NOTE:
• i-save operation cannot be selected during DRY or AUTO mode operation.
• The setting range of HEAT mode i-save operation is 10°C and 16 - 31°C.
• 2 groups of setting can be saved. (One for COOL/ECONO COOL, one for HEAT)
• i-save operation and the weekly timer operation cannot be used together.
2. How to cancel operation
• Press i-save button again.
• i-save operation can also be cancelled by pressing Operation select button to change the operation mode.
The preferred setting can be saved for the next time with a single press of i-save button.
9-12. 3-MINUTE TIME DELAY OPERATION
When the system turns OFF, compressor will not restart for 3 minutes as 3-minute time delay function operates to protect
compressor from overload.
Emergency operation switch
(E.O. SW)
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