Mitsubishi Electric NTXMMX A AA Series User manual

Models
NTXUKS09A112AA NTXUKS09A112BA
NTXUKS12A112AA NTXUKS12A112BA
NTXUKS18A112AA NTXUKS18A112BA
No. OBHT802
REVISED EDITION-B
INDOOR UNIT
SERVICE MANUAL
Outdoor unit service manual
NTXMMX•A•AA, NTXMPH•A•AA
Series (OBHT702, OCHT573)
PARTS CATALOG (OBBT802)
CONTENTS
1. TECHNICAL CHANGES···································· 2
2. PART NAMES AND FUNCTIONS····················· 3
3. SPECIFICATION················································ 4
4. OUTLINES AND DIMENSIONS························· 6
5. WIRING DIAGRAM············································ 7
6. REFRIGERANT SYSTEM DIAGRAM ··············· 9
7. SERVICE FUNCTIONS···································· 10
8. MICROPROCESSOR CONTROL···················· 13
9. TROUBLESHOOTING····································· 22
10. DISASSEMBLY INSTRUCTIONS···················· 37
OBHT802 REVISED EDITION-A is void.
Revision B:
• Specications of NTXUKS09/12/18A1112AA and
NTXUKS09/12/18A1112BA have been corrected.
• Some descriptions have been modied.

2
1TECHNICAL CHANGES
NTXUKS09A112AA
NTXUKS12A112AA
NTXUKS18A112AA
1. New model
NTXUKS09A112AA NTXUKS09A112BA
NTXUKS12A112AA NTXUKS12A112BA
NTXUKS18A112AA NTXUKS18A112BA
1. Indoor electronic control P.C. board 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.
<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 pull 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.
WARNING
• When the refrigeration circuit has a leak, do not execute pump down with the compressor.
• When pumping down the refrigerant, stop the compressor before disconnecting the refrigerant pipes.
The compressor may burst if air etc. get into it.
• When opening or closing the valve below freezing temperatures, refrigerant may spurt out from the gap
between the valve stem and the valve body, resulting in injuries.
Revision A:
• NTXUKS09A/12A/18A112BA have been added.
Revision B:
• Specications of NTXUKS09/12/18A1112AA and NTXUKS09/12/18A1112BA have been corrected.
• Some descriptions have been modied.
OBHT802B

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PART NAMES AND FUNCTIONS2
ACCESSORIES
MODELS NTXUKS09A112AA NTXUKS12A112AA NTXUKS18A112AA
NTXUKS09A112BA NTXUKS12A112BA NTXUKS18A112BA
Alkaline battery (AAA) for remote controller 2
Drain hose (with insulation) 1
Special washer (with cushion, 4pcs) 8
Installation template 1
Fixing screw for M5 х 30 mm 4
Band 1
Fixing screw for 4 х 16 mm 2
Remote controller 1
Remote controller holder 1
Fixing screw for 3.5 x 16 mm (Black) 2
INDOOR UNIT
NTXUKS09A112AA NTXUKS12A112AA NTXUKS18A112AA
NTXUKS09A112BA NTXUKS12A112BA NTXUKS18A112BA
Display section
Horizontal vane
Vertical vane
Air outlet
Air filter
(Air purifying filter)
Air inlet
Air cleaning filter
(Anti-Allergy Enzyme
filter, option)
Intake grille
Safety strings Spec name plate
Open the display cover Remote control receiving section
Emergency operation switch
Operation indicator lamp
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3 SPECIFICATION
Indoor model NTXUKS09A112AA
NTXUKS09A112BA
NTXUKS12A112AA
NTXUKS12A112BA
NTXUKS18A112AA
NTXUKS18A112BA
Power supply V, phase, Hz 208/230, 1, 60
Max. fuse size (time delay)/ Disconnect switch A15
Airow
High - Med. - Low - SLow
COOL Dry
(Wet)
CFM 311 - 282 - 254 - 212 332 - 297 - 258 - 212 403 - 346 - 293 - 212
HEAT Dry CFM 325 - 290 - 247 - 212 350 - 311 - 272 - 212 417 - 364 - 311 - 212
Sound level
High - Med. - Low - SLow
Cooling dB (A) 38 - 34 - 31 - 27 40 - 36 - 32 - 27 47 - 41 - 36 - 29
Heating dB (A) 37 - 34 - 29 - 26 40 - 36 - 32 - 26 48 - 42 - 37 - 26
Cond. drain connection O.D. in. Ø1 (26 mm)
Dimensions
W
in.
43-3/8
D14-3/16
H7-5/16
Weight Ib. 34
External nish White
Control voltage (by built-in transformer) 12 - 24 V DC
NOTE: Test conditions are based on ARI 210/240.
1. Multi connection
Specifications and rated conditions of main electric parts
Model
Item
NTXUKS09A112AA NTXUKS12A112AA NTXUKS18A112AA
NTXUKS09A112BA NTXUKS12A112BA NTXUKS18A112BA
Fuse (F11) T3.15AL250V
Horizontal vane motor (MV1) 12 V DC
Vertical vane motor (MV2) 12 V DC
Varistor (NR11) 470 V
DRAIN PUMP (DP) 230 V 6.4 W
FLOAT SENSOR (FS) 5 V DC
OBHT802B

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● The air coverage is the figure up to the
position where the air speed is 1 ft./s.,
when air is blown out horizontally from
the unit properly at the High speed
position.
The coverage should be used only
as a general guideline since it varies
according to the size of the room and
furniture arranged inside the room.
3-2. OUTLET AIR SPEED AND COVERAGE
1. Multi connection
Model Mode Function Airow
(CFM)
Air speed
(ft./s.)
Coverage
(ft.)
NTXUKS09A112AA
NTXUKS09A112BA
HEAT Dry 325 13.6 21.7
COOL Dry 311 13.0 20.7
Wet ———
NTXUKS12A112AA
NTXUKS12A112BA
HEAT Dry 350 14.6 23.3
COOL Dry 332 13.9 22.1
Wet ———
NTXUKS18A112AA
NTXUKS18A112BA
HEAT Dry 417 17.5 27.6
COOL Dry 403 16.9 26.7
Wet ———
(2) OPERATION
*The operating range of the outdoor unit depends on the connected outdoor unit.
Mode Condition
Intake air temperature (°F)
Indoor Outdoor
DB WB DB WB
Cooling
Standard temperature 80 67 95 —
Maximum temperature 90 73 115 —
Minimum temperature 67 57 14 —
Maximum humidity 78% —
Heating
Standard temperature 70 60 47 43
Maximum temperature 80 67 75 65
Minimum temperature 70 60 -13 -14
3-1. OPERATING RANGE
(1) POWER SUPPLY
Rated voltage Guaranteed voltage (V)
Indoor unit
208/230 V
1 phase
60 Hz
Min. 187 208 230 Max. 253
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4OUTLINES AND DIMENSIONS
Unit: inch
INDOOR UNIT
NTXUKS09A112AA NTXUKS12A112AA NTXUKS18A112AA
NTXUKS09A112BA NTXUKS12A112BA NTXUKS18A112BA
OBHT802B

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WIRING DIAGRAM5
INDOOR UNIT
NTXUKS09A112AA
NTXUKS12A112AA
NTXUKS09A112BA
NTXUKS12A112BA
OBHT802B

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NTXUKS18A112AA
NTXUKS18A112BA
OBHT802B

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REFRIGERANT SYSTEM DIAGRAM6
Indoor
heat
exchanger
Flared connection
Room temperature
thermistor
RT11
Indoor coil
thermistor
RT13 (sub)
Flared connection
Refrigerant pipe Ø3/8(Ø9.52)
(with heat insulator)
Refrigerant pipe Ø1/4(Ø6.35)
(with heat insulator)
Indoor coil
thermistor
RT12 (main)
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 Ø1/2(Ø12.7)
(with heat insulator)
Refrigerant pipe Ø1/4(Ø6.35)
(with heat insulator)
Indoor coil
thermistor
RT12,RT14,
RT15 (main)
INDOOR UNIT
Unit: inch(mm)
NTXUKS09A112AA
NTXUKS12A112AA
NTXUKS09A112BA
NTXUKS12A112BA
NTXUKS18A112AA
NTXUKS18A112BA
OBHT802B

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7SERVICE FUNCTIONS
7-1. 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.
NTXUKS09A112AA NTXUKS09A112BA
NTXUKS12A112AA NTXUKS12A112BA
NTXUKS18A112AA NTXUKS18A112BA
Table 1
7-2. 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.
2. How to set the remote controller
(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.
After the setting, turn ON the power supply and with the remote controller headed towards the indoor unit, press the
STOP/OPERATE (OFF/ON) button. If 1 or 2 beeps is heard from the indoor unit, the setting is completed correctly.
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.
1. How to modify the electronic control P.C. board
Turn OFF the power supply before modification. To assign a number to each indoor unit , cut off “JR05” and “JR06” on the
electronic control P.C. board as shown in Table 1. (Refer to 9-7.)
Unit No. 1
Unit No. 2
Unit No. 3
Unit No. 4
JR05
No modification
Cut off JR05
No modification
Cut off JR05
JR06
No modification
No modification
Cut off JR06
Cut off JR06
C111
IC101
JR05
JR06
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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 tripping 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.
C111
JR77
IC101
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 9-7.)
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.)
7-3. 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.
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Change dip switch SW3 setting according to the height of ceiling.
Dip switch SW3
Ceiling height
Normal
8.0 ft. (2.4 m) or below
Increase airflow volume
above 8.0 ft. (2.4 m) and 9.0 ft. (2.7 m) or below
How to change Dip switch (SW3) setting (Factory setting is normal)
1. Make sure that the breaker for air conditioner is turned OFF.
2. Remove the electrical cover (1) and (2) of the indoor unit.
3. Slide out the electronic control P.C. board, and switch up the slide switch (SW).
4. Put the electronic control P.C. board back to the original position, and install the electrical cover (1) and (2).
NOTE:
• Install the indoor unit at least 7.2 ft. (2.2 m) above floor or grade level.
• Perform static elimination before setting.
NOTE: When the ceiling is above 9.0 ft. (2.7 m), airflow volume may be insufficient even with the Dip switch (SW3) set to
"increase airflow".
Electrical cover (1)
Electrical cover (2)
Electronic
control P.C.
board
Slide switch SW3
Normal Up
(Increase airflow
volume)
7-4. P.C. BOARD MODIFICATION FOR CHANGING AIRFLOW VOLUME
How to change Dip switch (SWV1) setting (Factory setting is normal)
1. Make sure that the breaker for air conditioner is turned OFF.
2. Remove the electrical cover (1) and (2) of the indoor unit.
3. Slide out the electronic control P.C. board, and change the slide switch (SWV1) to up.
4. Put the electronic control P.C. board back to the original position, and install the electrical cover (1) and (2).
NOTE:
• Perform static elimination before setting.
Electrical cover (1)
Electrical cover (2)
Electronic
control P.C.
board
Slide switch SWV1
Normal Up
(Airflow direction
is heightened.)
(AUTO) (1) (2) (3) (4) (5) (SWING)
The setting when the higher airflow is preferred in the Airflow direction (1)
The angle of airflow direction (1) can be slightly heightened by changing SWV1 to up.
However, it may cause the dirt on the ceiling.
7-5. P.C. BOARD MODIFICATION FOR CHANGING AIRFLOW DIRECTION ADJUSTMENT
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MICROPROCESSOR CONTROL8
NTXUKS09A112AA NTXUKS12A112AA NTXUKS18A112AA
NTXUKS09A112BA NTXUKS12A112BA NTXUKS18A112BA
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.
INDOOR UNIT DISPLAY SECTION
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 4°F(2°C) or more
away from set tempera-
ture
The room temperature is
approaching the set tem-
perature
About 2 to 4°F(1 to 2°C)
from set temperature
Standby mode
(Refer to multi system
operation)
-
Lit
Blinking
Not lit
Signal transmitting section
Operation display section
TEMPERATURE buttons
STOP/OPERATE
(OFF/ON) button
Indication of
remote controller
model is on back
Distance of signal :
About 20 ft. (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
Lid
Slide the lid down
to open the remote
controller. Slide it down
further to get to the
weekly timer buttons.
WEEKLY TIMER
set buttons
TIME, TIMER set buttons
FORWARD button
BACKWARD button
RESET button
SMART SET button
SLEEP button VANE CONTROL button
POWERFUL button
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8-1. COOL ( ) OPERATION
(1) Press STOP/OPERATE(OFF/ON) 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 61 - 88°F (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.
NOTE: Do not operate COOL mode at low outside temperature [less than 14°F (-10°C)]. Water condensed in the unit may
drip and wet or damage furniture, etc.
8-2. DRY ( ) OPERATION
(1) Press STOP/OPERATE(OFF/ON) 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. (8-1.1.)
8-3. 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.
8-4. HEAT ( ) OPERATION
(1) Press STOP/OPERATE(OFF/ON) 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 50°F(10°C)
and 61 - 88°F (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. 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.
8-5. 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 have passed with the room temperature 4°F (2°C) below
the set temperature.
HEAT mode changes to COOL mode when about 15 minutes have passed with the room temperature 4°F (2°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”.
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NOTE 2
FOR MULTI SYSTEM AIR CONDITIONER
OUTDOOR UNIT: NTXMMX, NTXMPH 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 minutes) 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 flow-
ing may be heard, they are not malfunction. The reason is that the refrigerant continuously flows into it.
OPERATION INDICATOR
Lit
Blinking
Not lit
8-6. 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.
NOTE: The setting when the higher airflow is preferred in the Airflow direction (1)
The angle of airflow direction (1) can be slightly heightened by changing SWV1 to up.
(Refer to 8-5. P.C. BOARD MODIFICATION FOR CHANGING AIRFLOW DIRECTION ADJUSTMENT.)
However, it may cause the dirt on the ceiling.
Factory setting is normal.
(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 power supply turns on.
(b) When the operation starts or finishes (including timer operation).
(c) When the test run starts.
(d) When multi-standby starts or finishes.
(e) When the swing operation finishes.
(AUTO) (1) (2) (3) (4) (5) (SWING)
(5) STOP (operation OFF) and ON TIMER standby
In the following cases, the horizontal vane returns to the closed position.
(a) When STOP/OPERATE(OFF/ON) button is pressed (POWER OFF).
(b) When the operation is stopped by the emergency operation.
(c) When ON TIMER is ON standby.
(4) VANE AUTO ( ) mode
In VANE AUTO mode, the microprocessor automatically determines the vane angle and operation to make the opti-
mum room-temperature distribution.
1
4
Vane angle is fixed to Angle 1.
Vane angle is fixed to Angle 4.
(1) In COOL and DRY operation
(2) In HEAT operation
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(6) SWING ( ) mode
By selecting SWING mode with VANE CONTROL button, the horizontal vanes swing vertically.
When COOL, DRY or FAN mode is selected, only the upper vane swings.
(7) Cold air prevention in HEAT operation
The horizontal vane position is set to Upward.
(8) ECONO COOL ( ) operation (ECONOmical operation)
When ECONO COOL button is pressed in COOL mode, set temperature is automatically set 4°F(2°C) higher by
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, WIDE VANE CONTROL or VANE CONTROL button.
8-7. DRAIN PUMP/ FLOAT SENSOR CONTROL
1. Drain pump
Operating condition:
1. During COOL, DRY, or emergency COOL operation
2. When float sensor detects water level above fixed point during:
(a) HEAT operation.
(b) emergency HEAT operation.
(c) standby when during multi system operation.
(d) standby when ON timer is set.
(e) operation STOP.
Drain pump operates in conditions 1 or 2.
Operation stop condition:
Condition other than 1 or 2 indicated above.
2. Float sensor
Float moves with the up and down of water surface inside the drain pan, and judges water level.
(Fixed point differs at raised and lowered water levels.)
Float sensor
Water surface
Fixed point, when water level rises
Fixed point, when water level lowers
2. Vertical vane
(1) Press WIDE VANE CONTROL button to change horizontal airflow direction.
•The vertical vane moves for about 30 seconds.
(After 30 seconds, the vertical vane moves to its original position. In this case, press WIDE VANE CONTROL button
again.)
(2) Press WIDE VANE CONTROL button again to set horizontal airflow direction.
•The vertical vane stops and the airflow direction is set.
(3) Positioning
To confirm the standard position, the vane moves until it touches the vane stopper. Then the vane set to the desired
angle.
Confirming of standard position is performed in the following cases:
(a) When STOP/OPERATE(OFF/ON) button is pressed (POWER ON).
(b) When SWING is started.
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8-8. 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(OFF/ON) 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.
(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.
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8-9. WEEKLY TIMER OPERATION
E.g. : Runs at 75°F (24°C) from waking up to leaving home, and runs at
81°F (27°C) from getting home to going to bed on weekdays.
Runs at 81°F (27°C) from waking up late to going bed early on
weekends.
Setting1 Setting2 Setting3 Setting4
Setting1 Setting2
AM 6:00 AM 8:30 PM 5:30 PM 10:00
AM 8:00 PM 9:00
75°F (24°C) 81°F (27°C)
ON OFF ON OFF
FFONO
Mon
Fri
~
Sat
Sun
~
81°F (27°C)
• 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.
* 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 days and/or numbers.
(3) Press , , and buttons to set ON/OFF, time, and temperature.
* 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.
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 50°F(10°C).
• The weekly timer operation and SMART SET operation cannot be used together.
1. How to set the weekly timer
E.g. : [ON], [6:00] and
[75°F(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.
* The temperature can be set between 61°F and 88°F (16°C and 31°C) at weekly timer.
Press and buttons to continue setting the timer for other days and/or numbers.
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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 setting2. 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.
(4) Press button to complete and transmit the weekly timer setting.
* which was blink-
ing goes out, and the
current time will be
displayed.
8-10. SMART SET ( ) OPERATION
1. How to set SMART SET operation
(1) Press STOP/OPERATE(OFF/ON) button.
(2) Select COOL or HEAT mode.
(3) Press SMART SET button.
(4) Set the temperature, fan speed, and airow direction for SMART SET operation.
NOTE:
• SMART SET operation cannot be selected during DRY, FAN or AUTO mode operation.
• The setting range of HEAT mode SMART SET operation is 50°F (10°C) and 61 - 88°F (16 - 31°C).
• 2 groups of setting can be saved. (One for COOL, one for HEAT)
• SMART SET operation and the weekly timer operation cannot be used together.
• SMART SET operation and SLEEP operation cannot be set at the same time
2. How to cancel operation
• Press SMART SET button again.
• SMART SET 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 SMART SET button.
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8-11. SLEEP ( ) OPERATION
1. How to set SLEEP operation
(1) Press STOP/OPERATE (OFF/ON) button.
(2) Select COOL, DRY, HEAT or FAN mode.
(3) Press SLEEP ( ) button.
(4) PRESS TEMPERATURE buttons [ (Increase) and (Decrease) ] to set the temperature of SLEEP
operation.
Fan speed: AUTO
Horizontal vane: Position set on the remote controller
Operation indicator lamp: Dimly lit
• Once the above procedure is completed, the settings will be saved.
• After the settings are saved, a single push of SLEEP ( ) button during operation activates SLEEP operation with the
same settings every time.
• Temperature for SLEEP operation cannot be set during DRY or FAN mode.
Set temperature for SLEEP operation.
For about 30 minutes after SLEEP ( ) button is pressed, the set temperature remains as set for the operation running
when the SLEEP button is pressed. It will change to the set temperature for SLEEP operation in about 30 minutes.
Pressing SLEEP ( ) button again returns the operation to the previous settings.
is
pressed.
is
pressed.
For about 30
minutes
Set
temperature for
the operation
before SLEEP
operation
Set temperature for
SLEEP operation
Set temperature for
the operation before
SLEEP operation
NOTE:
• ON/OFF timer is available during SLEEP operation.
• When a preset ON time for the weekly timer arrives during SLEEP operation, the weekly timer operation has priority. SLEEP
operation will be cancelled, and the operation set on the weekly timer will start.
2. How to cancel operation
• Press SLEEP ( ) button again.
• The operation returns to the previous settings.
• SLEEP operation is also cancelled when the FAN button is pressed or the operation mode is changed.
NOTE: SLEEP operation and SMART SET operation cannot be set at same time.
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