Mitsubishi Electric MSZ-SF15VA-E1 User manual

Models
MSZ-SF15VA - E1 , E2 , E3 , E4 , ER3 , ER4
MSZ-SF20VA - E1 , E2 , E3 , E4 , ER3 , ER4
NOTE:
RoHS compliant products have <G> mark on the spec name plate.
INDOOR UNIT
SERVICE MANUAL
No. OBH555
REVISED EDITION-D
PARTS CATALOG (OBB555)
Revision D:
• MSZ-SF15/20VA- E4 , ER4 have been added.
Please void OBH555 REVISED EDITION-C.
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 ······························· 18
11. DISASSEMBLY INSTRUCTIONS ················· 30
Outdoor unit service manual
MXZ-B∙VA Series (OBH554)
MXZ-C∙VA Series (OBH584)
MXZ-D∙VA Series (OBH626)
MXZ-8A∙VA (OC316)
MXZ-8B∙VA (OCH480)
MXZ-E∙VA Series (OBH723)

2
MSZ-SF15VA - E1
MSZ-SF20VA - E1
1. New model
TECHNICAL CHANGES
1
Revision A:
• MSZ-SF15VA- E2 and MSZ-SF20VA- E2 have been added.
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.
MSZ-SF15VA - E1 MSZ-SF15VA - E2
MSZ-SF20VA - E1 MSZ-SF20VA - E2
1. Software has been changed for ERP.
<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 B:
• MSZ-SF15VA- E3 and MSZ-SF20VA- E3 have been added.
MSZ-SF15VA - E2 MSZ-SF15VA - E3
MSZ-SF20VA - E2 MSZ-SF20VA - E3
1. Model name has been changed.
Revision C:
• MSZ-SF15VA- ER3 and MSZ-SF20VA- ER3 have been added.
Revision D:
• MSZ-SF15/20VA- E4 , ER4 have been added.
MSZ-SF15VA - ER3
MSZ-SF20VA - ER3
1. New model
MSZ-SF15VA - E3 MSZ-SF15VA - E4
MSZ-SF20VA - E3 MSZ-SF20VA - E4
MSZ-SF15VA - ER3 MSZ-SF15VA - ER4
MSZ-SF20VA - ER3 MSZ-SF20VA - ER4
1. Logo design has been changed.
OBH555D

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ACCESSORIES
Installation plate 1
Installation plate f xing screw 4 × 25 mm 5
Remote controller holder 1
Fixing screw for 3.5 × 16 mm (Black) 2
Battery (AAA) for remote controller 2
Wireless remote controller 1
Felt tape (Used for left or left-rear piping) 1
MSZ-SF15VA MSZ-SF20VA
PART NAMES AND FUNCTIONS
2
Front panel
Air f lter
Air inlet
Horizontal vane
Air outlet
Heat exchanger
Operation
Remote control
indicator lamp
receiving section
Emergency operation switch (E.O. SW)
Remote controller
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Indoor model MSZ-SF15VA MSZ-SF20VA
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 RC0J40-FM
Current
1
Cooling A0.17 0.19
Heating 0.17 0.19
Dimensions W × H × D mm 760 × 250 × 168
Weight kg 7.7
Special remarks
Air direction 5
Airf ow
Cooling
Super High
m3/h
384 414
High 330
Med. 276
Low 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
1,500 1,600
High 1,300
Med. 1,130
Low 980
Silent 900
Heating
Super High
rpm
1,500 1,600
High 1,350
Med. 1,160
Low 1,030
Silent 910
Fan speed regulator 5
Remote controller model SG10D ( E1 , E2 , E3 , ER3 )/SG15D ( E4 , ER4 )
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.
2 For multi system.
Specifications and rating conditions of main electric parts
Fuse (F11) T3.15AL250V
Horizontal vane motor (MV) 12 VDC
Varistor (NR11) S10K300E2K1
Terminal block (TB) 3P
SPECIFICATION
3
OBH555D

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MSZ-SF15VA
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-SF20VA
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
OBH555D

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Unit: mm
MSZ-SF15VA MSZ-SF20VA
OUTLINES AND DIMENSIONS
5
11 20 Oblong hole
Installation plate
11 20 Oblong hole
Indoor unit
Wall hole 65
Ø
61 295 155 78
45 335 300
145 145
81
208
166
42
167
187
209
21.5
41
760
740 10
5 168
45 56 505 179
56
202
250
8
110
41
56
Installation plate
Piping
Drain hose
Air out
60
193
18
56 56
47
43
Piping
Insulation
Liquid line
Gas line
Drain hose
35 O.D
6.35-0.39m (Flared connection 6.35)
Ø
ØØ
9.52-0.34m (Flared connection 9.52)
ØØ
Insulation 28 Connected part 16 O.D
ØØ
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MSZ-SF15VA - E1 , E2 MSZ-SF20VA - E1 , E2
WIRING DIAGRAM
6
MSZ-SF15VA - E4 , ER4 MSZ-SF20VA - E4 , ER4
MSZ-SF15VA - E3 , ER3 MSZ-SF20VA - E3 , ER3
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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-SF15VA MSZ-SF20VA
REFRIGERANT SYSTEM DIAGRAM
7
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8-1. TIMER SHORT MODE
For service, the following set time can be shortened by bridging JPG and JPS 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. P.C. BOARD MODIFICATION FOR INDIVIDUAL OPERATION
(MSZ-SF15/20VA- E1 , E2 , E3 , ER3 )
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.
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 modification, take out the batteries
and press the STOP/OPERATE (MSZ-
SF·VA- E4 , ER4 )/OPERATE/STOP (Other
models) button 2 or 3 times at first.
After modification, put back the batteries
then press the RESET button.
Table 1
1 unit operation 2 units operation 3 units operation 4 units operation
No. 1 unit No modif cation Same as at left Same as at left Same as at left
No. 2 unit — Solder J1 Same as at left Same as at left
No. 3 unit — — Solder J2 Same as at left
No. 4 unit — — — Solder both J1 and J2
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 is turned OFF, or the power supply is shut down.
Please conduct the above setting once again after the power has restored.
MSZ-SF15VA MSZ-SF20VA
SERVICE FUNCTIONS
8
J1 J2
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8-4. 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.
Solder the jumper wire to JR07 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
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.
CN112
R111
Indoor electronic
control P.C. board
JR07
IC112
CN151
CN111
CN211
D
8-3. HOW TO SET REMOTE CONTROLLER EXCLUSIVELY FOR A PARTICULAR INDOOR UNIT
(MSZ-SF15/20VA- E4 , ER4 )
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.
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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-SF15VA MSZ-SF20VA
MSZ-SF15VA- E1 , E2 , E3 , ER3 MSZ-SF20VA- E1 , E2 , E3 , ER3
MSZ-SF15VA- E4 , ER4 MSZ-SF20VA- E4 , ER4
Signal transmitting section
Operation display section
TEMPERATURE buttons
OPERATE/STOP
(ON/OFF) button
Indication of
remote controller
model is on back
FAN SPEED CONTROL button
OPERATION SELECT button
ECONO COOL button
CLOCK SET button
WEEKLY TIMER
set button
TIME, TIMER set buttons
FORWARD button
BACKWARD button
RESET button
i save button
VANE CONTROL button
Signal transmitting section
Operation display section
TEMPERATURE buttons
STOP/OPERATE
(OFF/ON) button
Indication of
remote controller
model is on back
FAN SPEED CONTROL button
OPERATION SELECT button
ECONO COOL button
CLOCK SET button
WEEKLY TIMER
set button
TIME, TIMER set buttons
FORWARD button
BACKWARD button
RESET button
i save button
VANE CONTROL button
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9-2. DRY ( ) OPERATION
(1) Press STOP/OPERATE (MSZ-SF·VA- E4 , ER4 )/OPERATE/STOP (Other models) 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 (MSZ-SF·VA- E4 , ER4 )
(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 STOP/OPERATE (MSZ-SF·VA- E4 , ER4 )/OPERATE/STOP (Other models) 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 16 - 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.
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
Lighted
Blinking
Not lighted
9-1. COOL ( ) OPERATION
(1) Press STOP/OPERATE (MSZ-SF·VA- E4 , ER4 )/OPERATE/STOP (Other models) 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.
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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 flashes 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 the heating 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
Lighted
Blinking
Not lighted
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 12345 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 STOP/OPERATE (MSZ-SF·VA- E4 , ER4 )/OPERATE/STOP (Other models) 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 SET button.
How to set the current time
(a) Press the CLOCK set button.
(b) Press the TIME SET buttons ( and ) to set the current time.
• Each time FORWARD button ( ) is pressed, the set time increases by 1 minute, and each time BACKWARD
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 set button.
(2) Press STOP/OPERATE (MSZ-SF·VA- E4 , ER4 )/OPERATE/STOP (Other models) 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 FORWARD button ( ) is pressed, the set time increases by 10 minutes: each time BACKWARD but-
ton ( ) 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.
MSZ-SF15/20- , , ,
E3E2E1 ER3
MSZ-SF15/20- ,
E4 ER4
E3E2E1 ER3
MSZ-SF15/20- ,
E4 ER4
MSZ-SF15/20- , , ,
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
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 different setting is included among them, will be
displayed.
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17
9-10. EMERGENCY/TEST OPERATION
In the case of test run operation or emergency operation, use
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 EMERGENCY
OPERATION switch is pressed once or twice or the unit receives any
signal from the remote controller. In the latter case, normal operation
will start.
NOTE: Do not press EMERGENCY OPERATION switch during normal operation.
Operation mode COOL/HEAT
Set temperature 24°C
Fan speed Med.
Horizontal vane Auto
The operation mode is indicated by the
Operation Indicator lamp as following
Operation Indicator lamp
EMERGENCY COOL
↓
EMERGENCY HEAT
↓
STOP
Lighted
Not lighted
9-9. i-save ( ) OPERATION
1. How to set i-save operation
(1) Press STOP/OPERATE (MSZ-SF·VA- E4 , ER4 )/OPERATE/STOP (Other models) button.
(2) Select COOL, HEAT or ECONO COOL mode.
(3) Press i-save button.
(4) Set the temperature, fan speed, and airf 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 same setting is selected from the next time by simply pressing i-save button.
9-11. 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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18
RESET button
Insert the negative pole of the
batteries first. Check if the polarity
of the batteries is correct.
NOTE: 1. If RESET button is not pressed, the remote controller may not operate correctly.
2. This remote controller has a circuit to automatically reset the microcomputer when batteries are replaced.
This function is equipped to prevent the microcomputer from malfunctioning due to the voltage drop caused by the
battery replacement.
3. Do not use the leaking batteries.
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, 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 P.C. board.
3) When removing the 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 connector housing. DO NOT pull the lead wires.
3. Troubleshooting procedure
1) 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 OPERATION INDICATOR is flashing ON and OFF before starting service
work.
2) Before servicing, check that the connector and terminal are connected properly.
3) If the P.C. board is supposed 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.
4. How to replace batteries
Weak batteries may cause the remote controller malfunction.
In this case, replace the batteries to operate the remote controller normally.
Press RESET button with a thin instrument, and
then use the remote controller.
Remove the front lid and insert batteries.
Then reattach the front lid.
Lead wiring Connector housing
<Incorrect> <Correct>
MSZ-SF15VA MSZ-SF20VA
TROUBLESHOOTING
10
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10-2. FAILURE MODE RECALL FUNCTION
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.
1. Flow chart of failure mode recall function for the indoor/outdoor unit
Does left lamp of OPERATION INDICATOR lamp
on the indoor unit blink at the interval of 0.5 sec-
onds?
Blinks: Either indoor or outdoor unit is abnormal.
Beep is emitted at the same timing as the
blinking of upper lamp of OPERATION
INDICATOR lamp. 2
Indoor unit is normal.
But the outdoor unit might be abnormal because there are some abnor-
malities that cannot be recalled with this way.
Check if outdoor unit is abnormal according to the detailed outdoor unit
failure mode recall function.
No
Yes
The cause of abnormality cannot be found because the abnormality does not recur.
Turn ON the power supply.
<Preparation of the remote controller>
While pressing both OPERATION SELECT button and TEMP button on the remote
controller at the same time, press RESET button.
First, release RESET button.
Hold down the other 2 buttons for another 3 seconds.
Make sure that the indicators on the LCD screen shown in the right f gure are all
displayed. Then release the buttons.
Press STOP/OPERATE (MSZ-SF·VA-E4 , ER4 )/OPERATE/STOP (Other models)
button of the remote controller (the set temperature is displayed) with the remote control-
ler headed towards the indoor unit. 1
Before blinking, does left lamp of
OPERATION INDICATOR lamp stay ON for 3
seconds?
When it stays ON for 3 seconds (without beep):
The outdoor unit is abnormal.
The indoor unit is abnormal.
Check the blinking pattern, and identify the abnormal point by referring to the
indoor unit failure mode table. (Refer to 10-2.2)
Make sure to check at least 2 consecutive blinking cycles. 2
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 identify the abnormal point by referring
to the outdoor unit failure mode table. (Refer to outdoor unit service
manual.)
Make sure to check at least 2 consecutive blinking cycles. 3
Repair the failure parts.
After repairing the unit, recall the failure mode again according to "Setting up the failure mode recall
function" mentioned above.
Press STOP/OPERATE (MSZ-SF·VA-E4 , ER4 )/OPERATE/STOP (Other models) button of the
remote controller (the set temperature is displayed) with the remote controller headed towards the
indoor unit.
Press EMERGENCY OPERATION switch so that the memorized abnormal condition is deleted.
Release the failure mode recall function according to "Releasing the failure mode recall function"
mentioned above.
Setting up the failure mode recall function
Judgment of indoor/outdoor abnormality
Releasing the failure mode recall function
Deleting the memorized abnormal condition
Operational procedure
Yes
(Blinks)
No
(OFF)
NOTE: 1. Make sure to release the failure mode recall function after it is 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.
3.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
1 Regardless of normal or abnormal condition,
a short beep is emitted once the signal is re-
ceived.
MSZ-SF15VA-
E1
,
E2
,
E3
,
ER3
MSZ-SF20VA-
E1
,
E2
,
E3
,
ER3
MSZ-SF15VA-
E4
,
ER4
MSZ-SF20VA-
E4
,
ER4
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2. Indoor unit failure mode table
Left lamp of OP-
ERATION INDICA-
TOR lamp
Abnormal point
(Failure mode) Condition Remedy
Not lighted Normal — —
1-time f ash every
0.5-second
Room temperature
thermistor
The room temperature thermistor short or
open circuit is detected every 8 seconds dur-
ing operation.
Refer to the characteristics of the room temperature
thermistor (10-7.).
2-time f ash
2.5-second OFF
Indoor coil
thermistor
The indoor coil thermistor short or open circuit
is detected every 8 seconds during operation.
Refer to the characteristics of the main indoor coil ther-
mistor, the sub indoor coil thermistor (10-7.).
3-time f ash
2.5-second OFF Serial signal The serial signal from outdoor unit is not re-
ceived for a maximum of 6 minutes.
Refer to 10-6. "How to check miswiring and serial
signal error".
11-time f ash
2.5-second OFF Indoor fan motor
The rotational frequency feedback signal is not
emitted during the 12 seconds the indoor fan
operation.
Refer to 10-6. "Check of indoor fan motor".
12-time f ash
2.5-second OFF
Indoor control
system
It cannot properly read data in the nonvolatile
memory of the indoor electronic control P.C.
board.
Replace the indoor electronic control P.C. board.
NOTE: Blinking patterns of this mode differ from the ones of TROUBLESHOOTING CHECK TABLE (10-4.).
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