Mitsubishi Electric Trane NTXWPH06B112AA User manual

INDOOR UNIT
SERVICE MANUAL
INDOOR UNIT No. OBHT872
PARTS CATALOG (OBBT872)
Outdoor unit service manual
NTXSPB/SPH∙B112AA Series (OBHT873)
NTXMMX/MPH∙A122AA Series (OBHT702)
CONTENTS
1. TECHNICAL CHANGES ······························3
2. PART NAMES AND FUNCTIONS ··················4
3. SPECIFICATION·········································5
4. OUTLINES AND DIMENSIONS ·····················6
5. WIRING DIAGRAM ·····································7
6. REFRIGERANT SYSTEM DIAGRAM ·············8
7. SERVICE FUNCTIONS································9
8. MICROPROCESSOR CONTROL················· 11
9. TROUBLESHOOTING·······························20
10. DISASSEMBLY INSTRUCTIONS·················33
Models
NTXWPH06B112AA
NTXWPH09B112AA
NTXWPH12B112AA
NTXWPH15B112AA
NTXWPH18B112AA

2
Use the specied refrigerant only
Never use any refrigerant other than that specified.
Doing so may cause a burst, an explosion, or fire when the unit is being used, serviced, or disposed of.
Correct refrigerant is specified in the manuals and on the spec labels provided with our products.
We will not be held responsible for mechanical failure, system malfunction, unit breakdown or accidents caused by
failure to follow the instructions.
OBHT872

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1TECHNICAL CHANGES
NTXWPH06B112AA
NTXWPH09B112AA
NTXWPH12B112AA
NTXWPH15B112AA
NTXWPH18B112AA
1. New model
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2PART NAMES AND FUNCTIONS
ACCESSORIES
Model
NTXWPH06B112AA
NTXWPH09B112AA
NTXWPH12B112AA
NTXWPH15B112AA
NTXWPH18B112AA
Installation plate 1
Attachment screws for the installation
plate 4 × 25 mm 5
Remote controller holder 1
Screw for the remote controller holder
3.5 × 16 mm (Black) 2
Battery (AAA) for the remote controller 2
Wireless remote controller 1
Felt tape (For left or left-rear piping) 1
Air cleaning lter
(Electrostatic anti-allergy enzyme lter) 1
Air cleaning lter (Deodorizing lter) 1
Operation indicator lamp Remote control receiving
section
Emergency
operation
switch
Horizontal
vane
Air inlet
Air filter
(Nano platinum filter)
Air cleaning filter
(Electrostatic anti-allergy
enzyme filter and deodorizing fiter)
Front panel
Air outlet
i-see sensor
Remote controller
NTXWPH06B112AA NTXWPH09B112AA NTXWPH12B112AA NTXWPH15B112AA
NTXWPH18B112AA
OBHT872

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3SPECIFICATION
3-2. OUTLET AIR SPEED AND COVERAGE
● 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 var-
ies according to the size of the
room and furniture arranged inside
the room.
(2) OPERATION
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
Model Mode Function Airow
(CFM) Air speed (ft./s)
Coverage (ft.)
NTXWPH06B112AA
HEAT Dry 437 19.5 29.8
COOL Dry 381 17.0 26.1
Wet 328 14.6 22.5
NTXWPH09B112AA
HEAT Dry 437 19.5 29.8
COOL Dry 381 17.0 26.1
Wet 328 14.6 22.5
NTXWPH12B112AA
HEAT Dry 454 20.3 31.0
COOL Dry 424 19.0 29.0
Wet 364 16.2 24.8
NTXWPH15B112AA
HEAT Dry 514 23.0 34.9
COOL Dry 437 19.5 29.8
Wet 376 16.7 25.6
NTXWPH18B112AA
HEAT Dry 514 23.0 34.9
COOL Dry 437 19.5 29.8
Wet 376 16.7 25.6
Indoor unit model
NTXWPH06B112AA NTXWPH09B112AA NTXWPH12B112AA NTXWPH15B112AA NTXWPH18B112AA
Power supply V, phase, Hz 208/230 , 1 , 60
Disconnect switch A 15
Min. circuit ampacity A 1.0
Fan motor F.L.A 0.65
Airow
Super high - High -
Med. - Low - Quiet
COOL Dry
(Wet)
CFM
381- 304 - 221 - 167 - 137
(328 - 261 - 190 - 143 - 117)
381- 304 - 221 - 167 - 137
(328 - 261 - 190 - 143 - 117)
424 - 304 - 221 - 167 - 137
(364- 261 - 190 - 143 - 117)
437 - 355 - 304 - 262 - 225
(376 - 305 - 261 - 225 - 194)
437 - 355 - 304 - 262 - 225
(376 - 305 - 261 - 225 - 194)
HEAT Dry CFM 437 - 381 - 225 - 167 - 140 437 - 381 - 225 - 167 - 140 454 - 367 - 282 - 226 - 155 514 - 410 - 350 - 272 - 201 514 - 410 - 350 - 272 - 201
Moisture removal pt./h 0.2 0.6 1.9 4.0 5.1
Sound level
Super high - High -
Med. - Low - Quiet
Cooling dB(A) 40 - 36 - 29 - 23 - 20 40 - 36 - 29 - 23 - 20 44 - 36 - 29 - 24 - 21 44 - 39 - 35 - 31 - 27 44 - 39 - 35 - 31 - 27
Heating dB(A) 42 - 39 - 29 - 24 - 20 42 - 39 - 29 - 24 - 20 43 - 38 - 32 - 28 - 21 46 - 40 - 37 - 31 - 25 46 - 40 - 37 - 31 - 25
Cond. drain connection O.D. in. 5/8
Dimensions Win. 36-7/16 D 9-3/16
H 12 (+ 11/16)
Weight Ib. 29
External nish Munsell 1.0Y 9.2/0.2
Remote controller Wireless type
Control voltage (by built-in transformer) 12 - 24 VDC
NOTE: Test conditions are based on AHRI 210/240.
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4OUTLINES AND DIMENSIONS
Unit: inch
NTXWPH06B112AA NTXWPH09B112AA NTXWPH12B112AA NTXWPH15B112AA
NTXWPH18B112AA
(NTXWPH06/09/12B112AA) (NTXWPH15/18B112AA)
OBHT872

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5WIRING DIAGRAM
NTXWPH06B112AA NTXWPH09B112AA NTXWPH12B112AA NTXWPH15B112AA
NTXWPH18B112AA
OBHT872

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6REFRIGERANT SYSTEM DIAGRAM
Indoor
heat
exchanger
Flared connection
Room temperature
thermistor
RT11
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 coil
thermistor
RT13 (sub)
Refrigerant flow in cooling
Refrigerant flow in heating
Unit: inch (mm)
Indoor
heat
exchanger
Flared connection
Room temperature
thermistor
RT11
Flared connection
Refrigerant pipe ø1/2 (ø12.7)
(with heat insulator)
Refrigerant pipe ø1/4 (ø6.35)
(with heat insulator)
Indoor coil
thermistor
RT12 (main)
Indoor coil
thermistor
RT13 (sub)
Refrigerant flow in cooling
Refrigerant flow in heating
NTXWPH15B112AA NTXWPH18B112AA
NTXWPH06B112AA NTXWPH09B112AA NTXWPH12B112AA
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7SERVICE FUNCTIONS
7-1. 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 9-7.)
Set time: 3 minutes → 3 seconds (It takes 3 minutes for the compressor to start operation. However, the starting time is
shortened by bridging JPG and JPS.)
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.
(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 you turn the breaker ON, the remote controller that first sends a signal to an indoor unit will be regarded as the
remote controller for the indoor unit.
Once they are set, the indoor unit will only receive the signal from the assigned remote controller afterwards.
7-3. SETTING THE INSTALLATION POSITION
Be sure to set the remote controller according to the installed position of the indoor unit.
Installation position:
Left: Distance to objects (wall, cabinet, etc.) is less than 50 cm to the left
Center: Distance to objects (wall, cabinet, etc.) is more than 50 cm to the left and right
Right: Distance to objects (wall, cabinet, etc.) is less than 50 cm to the right
The installation position 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 position setting mode.
(2) Select the target installation position by pressing button. (Each press of the button displays the
positions in order: center → right → left.)
(3) Press button to complete the position setting.
Installation position Left Center Right
Remote controller
display
(Left)(Center)(Right)
NTXWPH06B112AA NTXWPH09B112AA NTXWPH12B112AA NTXWPH15B112AA
NTXWPH18B112AA
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7-4. 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.
Cut the jumper wire to JR77 on the indoor electronic control P.C. board. (Refer to 9-7.)
NOTE:
• The operation settings are memorized when 10 seconds have passed after the indoor unit was operated with the remote
controller.
• If main power is turned OFF or a power failure occurs while AUTO START/STOP timer is active, the timer setting is can-
celled.
• If the unit has been 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.
JR77
CN110CN151
BZ
Indoor electronic control
P.C. board
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8MICROPROCESSOR CONTROL
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 temperature
The room temperature is approaching the set tem-
perature. About 2 to 4°F (1 to 2°C)
from set temperature
Standby mode (only during
multisystem operation) —
Lighted
Blinking
Not lighted
Signal transmitting section
Operation display section
(Backlight display*)
Temperature buttons
OFF/ON
(stop/operate) 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
INDIRECT/DIRECT button
ECONO COOL button
POWERFUL button
CLOCK button
Lid
Slide the lid down
to open the remote
controller. Slide it down
further to get to the
weekly timer buttons.
TIME, WEEKLY TIMER
set buttons
TIME, TIMER set buttons
forward button
backward button
RESET button
SMART SET button
NATURAL FLOW button
SENSOR (i-see) button
VANE control button
WIDE VANE button
Operation select button
* The backlight turns on when using the remote controller.
The backlight goes o󰀨 if the remote controller is not used for a while.
NTXWPH06B112AA NTXWPH09B112AA NTXWPH12B112AA NTXWPH15B112AA
NTXWPH18B112AA
OBHT872

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8-4. 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 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. 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.
8-2. 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. (8-1.1.)
2. Low outside temperature operation
Low outside temperature operation works the same way as that in COOL mode. (8-1.2.)
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.
8-1. 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 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.
2. Low outside temperature operation
When the outside temperature is lower, low outside temperature operation starts, and the outdoor fan slows or stops.
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 2°F (1°C) below
the set temperature.
HEAT mode changes to COOL mode when about 15 minutes have passed with the room temperature 2°F (1°C) above
the set temperature.
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8-6. AUTO VANE OPERATION
1. Horizontal vane
(1) Vane motor drive
These models are equipped with a stepping motors for the horizontal vanes. 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.
AUTO 1 2 5 SWING43
(AUTO) (1) (2) (3) (4) (5) (SWING)
NOTE: The right and left horizontal vanes set to the same level may not align perfectly.
(7) 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.
(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 4°F (2°C) higher by the
microprocessor. However, the temperature on the LCD screen on the remote controller is not changed. Also the hori-
zontal 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, POWERFUL or NATURAL FLOW button.
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.
(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 3 for dew prevention.
(3) Positioning
To confirm the standard position, the vane move until it touches the vane stopper. Then the vane is set to the select-
ed 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.
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(10) POWERFUL ( ) operation
The air conditioner automatically adjusts the fan speed and the set temperature, and operates the POWERFUL mode.
The POWERFUL mode is cancelled automatically 15 minutes after operation starts, or when POWERFUL button
is pressed once again within 15 minutes after operation starts. The operation mode returns to the mode prior to
POWERFUL operation. POWERFUL mode also is cancelled, when the OFF/ON (stop/operate), ECONO COOL,
FAN
speed control, NATURAL FLOW or SMART SET button is pressed within 15 minutes after operation starts, or operation
mode is changed.
2. Vertical vane
(1) Vane motor drive
These models are equipped with a stepping motor for the vertical vane. The rotating direction, speed, and angle of
the motor are controlled by pulse signals (approximately 12 V) transmitted from microprocessor.
(2) The vertical vane angle and mode change as follows by pressing WIDE VANE button.
(3) Positioning
To confirm the standard position, the vane moves until it touches the vane stopper. Then the vane is set to the select-
ed angle.
Confirming of standard position is performed in the following cases:
(a) OFF/ON (stop/operate) button is pressed (POWER ON).
1 2 3 4 5
(SWING)
(4) SWING ( ) MODE
By selecting SWING mode with WIDE VANE button, the vertical vane swings horizontally. The remote controller
displays “ ”. Swing mode is cancelled when WIDE VANE button is pressed once again.
8-7. 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 “12:00 AM” 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 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 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 forward button ( ) is pressed, the set time increases by 10 minutes: each time backward 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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8-8. 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.
75°F (24°C) 81°F (27°C)
PM 5:30AM 6:00 AM 8:30 PM 10:00
PM 9:00PM 8:00 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.
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 can not be set to 50°F (10°C).
• The weekly timer operation and SMART SET operation cannot be used together.
(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.
OBHT872

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* 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.
(3) Press , , and buttons to set ON/OFF, time, and temperature.
E.g. : [ON], [AM 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.
* 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
Press and buttons to continue setting the timer for other days and/or numbers.
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.
(4) Press button to complete and transmit the weekly timer setting.
* which was blink-
ing goes out, and the
current time will be
displayed.
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8-9. i-see CONTROL ( ) MODE
In the i-see control mode, the room temperature is controlled based on the sensible temperature.
(1)
Press SENSOR button with a thin instrument during COOL, DRY, HEAT and AUTO mode to activate i-see control mode ( ).
The default setting is “active”.
(2) Press SENSOR button again to activate ABSENCE DETECTION ( ).
(3) Press SENSOR button again to release i-see control mode.
ABSENCE DETECTION ( )
This function automatically changes the operation to energy-saving operation when nobody is in the room.
(1) To activate this function, press SENSOR button until appears on the operation display of the remote controller during the
i-see control mode.
(2) Press SENSOR button again to release ABSENCE DETECTION.
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.
(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.
NOTE:
Any person at the following places cannot be detected:
• Along the wall on which the air conditioner is installed
• Directly under the air conditioner
• Where any obstacle, such as furniture, is between the person and the air conditioner
A person may not be detected in the following situations:
• Room temperature is high.
• A person wears heavy clothes and his/her skin is not exposed.
• A heating element of which temperature changes signicantly is present.
• Some heat sources, such as a small child or pet, may not be sensed.
• A heat source and the air conditioner are more than 20 ft. (6 m) apart.
• A heat source does not move for a long time.
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8-11. NATURAL FLOW ( ) OPERATION
In NATURAL FLOW operation, air ow will become more like natural wind. An occupant will not be directly exposed to the
air ow and feel more comfortable.
(1) Press NATURAL FLOW button during COOL or FAN mode to start NATURAL FLOW operation.
(2) Press NATURAL FLOW button again to cancel NATURAL FLOW operation.
• NATURAL FLOW operation is also cancelled when the POWERFUL or ECONO COOL button is pressed.
NOTE: As the fan speed changes constantly during NATURAL FLOW operation, the sound of air ow, wind velocity and air ow
temperature also change. This is not a malfunction.
8-12. SMART SET ( ) OPERATION
1. How to set SMART SET operation
(1) Press OFF/ON (stop/operate) button.
(2) Select COOL, HEAT or ECONO COOL 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 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/ECONO COOL, one for HEAT)
• SMART SET operation and the weekly timer operation cannot be used together.
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 same setting is select from the next time by simply pressing SMART SET button.
8-10. INDIRECT/DIRECT MODE
The INDIRECT/DIRECT mode o󰀨ers nely-tuned operation by locating where an occupant is in the room.
(1) Press INDIRECT/DIRECT button during COOL, DRY, HEAT or AUTO mode to activate INDIRECT/DIRECT mode.
This mode is only available when the i-see control mode is e󰀨ective.
(2) Each press of INDIRECT/DIRECT button changes INDIRECT/DIRECT in the following order:
(INDIRECT): An occupant will be less exposed to direct airflow.
(DIRECT) : Mainly the vicinity of an occupant will be air-conditioned.
(INDIRECT) (DIRECT) (OFF)
NOTE:
• Horizontal and vertical airow directions will be automatically selected.
• If you still feel uncomfortable with the air direction determined by the INDIRECT mode, adjust the air direction manually.
• Cancelling the i-see control mode automatically cancels the INDIRECT/DIRECT mode.
INDIRECT/DIRECT mode is also cancelled when the VANE control or WIDE VANE buttons is pressed.
• Do not touch the i-see sensor. This may cause malfunction of the i-see sensor.
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8-13. EMERGENCY/TEST OPERATION
In the case of test run operation or the emergency operation, use the emergency operation switch on the right side of the
indoor unit. The emergency operation is available when the remote controller is missing 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 operation is for servicing. The indoor fan runs at High
speed and the temperature control does not work.
After 30 minutes of test run operation, the system shifts to
EMERGENCY COOL/HEAT MODE with a set temperature of
75°F (24°C). The fan speed shifts to Medium.
The coil frost prevention works even in the test run or the emergency operation.
In the test run or the emergency operation, the horizontal vane operates in VANE AUTO ( ) mode.
The emergency operation continues until the 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 the emergency operation switch during normal operation.
Operation mode COOL/HEAT
Set temperature 75°F (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
8-14. 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)
8-15. Changing temperature indication (°F/°C)
• The preset unit is °F.
• °F → °C: Press RESET button while the Temperature buttons are pressed.
• °C → °F: Press RESET button or remove the batteries .
Press RESET button gently
using a thin instrument.
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9TROUBLESHOOTING
9-1. CAUTIONS ON TROUBLESHOOTING
1. Before troubleshooting, check the following
1) Check the power supply voltage.
2) Check the indoor/outdoor connecting wire for 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 blinking ON and OFF to indicate an abnormality.
To make sure, check how many times the OPERATION INDICATOR lamp is blinking ON and OFF before starting ser-
vice work.
2) Before servicing, verify that all connectors and terminals are connected properly.
3) When the electronic control P.C. board seems to be defective, check for disconnection of the copper foil pattern and
burnt or discolored components.
4) When troubleshooting, Refer to 9-2, 9-3 and 9-4.
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.
Lead wiring Connector housing
<Incorrect> <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.
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.
Insert the negative pole of the
batteries first. Check if the polarity
of the batteries is correct.
RESET button
NTXWPH06B112AA NTXWPH09B112AA NTXWPH12B112AA NTXWPH15B112AA
NTXWPH18B112AA
OBHT872