NTXUKS06A112AA Split Type Air Conditioner Instruction Manual
- June 17, 2024
- NTXUKS
Table of Contents
- NTXUKS06A112AA Split Type Air Conditioner
- Product Information
- Product Usage Instructions
- FAQs
- TECHNICAL CHANGES
- SPECIFICATION
- OUTLINES AND DIMENSIONS
- WIRING DIAGRAM
- SERVICE FUNCTIONS
- MICROPROCESSOR CONTROL
- TROUBLESHOOTING
- DISASSEMBLY INSTRUCTIONS
- Read User Manual Online (PDF format)
- Download This Manual (PDF format)
NTXUKS06A112AA Split Type Air Conditioner
Product Information
Specifications
- Model: NTXUKS06A112AA
- Revision: A
- Power Supply: 208/230V, 1 phase, 60Hz
- Max. Fuse Size (time delay)/Disconnect Switch: 15A
- Airflow: High – Med. – Low – SLow
- Cooling Airflow (CFM): 198 – 184 – 166 – 152
- Heating Airflow (CFM): 212 – 194 – 173 – 152
- Sound Level: High – Med. – Low – SLow
- Cooling Sound Level (dB): 36 – 34 – 31 – 29
- Heating Sound Level (dB): Cooling Heating Cond. Drain Connection O.D.: in.
- Dimensions (D x H): in.
- Weight: lb.
- External Finish: Control Voltage (by built-in transformer):
Product Usage Instructions
Safety Precautions
- 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.
- Prepare the proper tools and 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 working on the electric parts.
- Do not perform work involving electric parts with wet hands. Do not pour water into the electric parts.
- Do not touch the refrigerant or the hot/cold areas in the refrigeration cycle.
- Exercise great caution when repairing or inspecting the circuit without turning off the power to avoid touching live parts.
FAQs
- Q: What refrigerant should I use with this product?
- A: You should use the refrigerant specified in the manuals and on the spec labels provided with our products. Using any other refrigerant may cause mechanical failure, system malfunction, unit breakdown, or accidents. We will not be held responsible for such issues caused by failure to follow the instructions.
- Q: What should I do before working on the electric parts of the unit?
- A: Before working on the electric parts, make sure to stop the operation of the air conditioner, turn off the power-supply breaker, and pull the power plug. Additionally, discharge the capacitor to ensure safety.
- Q: Can I touch the refrigerant or the hot/cold areas in the refrigeration cycle?
- A: No, you should not touch the refrigerant or the hot/cold areas in the refrigeration cycle. This can result in injuries. Exercise caution and avoid contact.
Revision A:
· Specifications of NTXUKS06A112AA have been corrected.
OBHT922 is void.
INDOOR UNIT
SERVICE MANUAL
Model
NTXUKS06A112AA
No. OBHT922
REVISED EDITION-A
Outdoor unit service manual NTXMMX·A·BA, NTXMPH·A·BA Series (OBHT702)
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.
TECHNICAL CHANGES
NTXUKS06A112AA
1. New model
OBHT922A
2
2 PART NAMES AND FUNCTIONS
INDOOR UNIT NTXUKS06A112AA
Air inlet Air outlet
Horizontal vane Vertical vane Intake grille
Air cleaning filter (Anti-allergy Enzyme
Filter, option)
Air filter (Air purifying filter)
Spec name plate Safety strings
Display section
ACCESSORIES
OBHT922A
Operation indicator lamp
Remote control receiving section Emergency operation switch
MODELS
(1) Alkaline battery (AAA) for remote controller (2) Drain hose (with
insulation) (3) Special washer (with cushion, 4pcs) (4) Installation template
(5) Fixing screw for (4) M5 30 mm (6) Band (7) Fixing screw for (6) 4 16 mm
(8) Remote controller (9) Remote controller holder (10) Fixing screw for (9)
3.5 x 16 mm (Black)
3
NTXUKS06A112AA
2 1 8 1 4 1 2 1 1 2
SPECIFICATION
1. Multi connection
Indoor model
Power supply
V, phase, Hz
Max. fuse size (time delay)/ Disconnect switch A
Airflow High – Med. – Low – SLow
COOL Dry (Wet) CFM
HEAT Dry
CFM
Sound level High – Med. – Low – SLow
Cooling Heating
dB (A) dB (A)
Cond. drain connection O.D.
in.
W
Dimensions
D
in.
H
Weight
Ib.
External finish
Control voltage (by built-in transformer)
NOTE: Test conditions are based on ARI 210/240.
NTXUKS06A112AA
208/230, 1, 60 15
198 – 184 – 166 – 152
212 – 194 – 173 – 152 36 – 34 – 31 – 29
37 – 35 – 32 – 29 ø1 (26 mm) 33-3/16 11-7/8 7-11/16 25 White 12 – 24 V DC
Specifications and rated conditions of main electric parts
Model Item
Fuse
(F11)
Horizontal vane motor Vertical vane motor Varistor
(MV1) (MV2) (NR11)
DRAIN PUMP DRAIN SENSOR
(DP) (DS)
NTXUKS06A112AA
T3.15AL250V 12 V DC 12 V DC 470 V
230 V 6.4 W Thermistor 25°C 5.3k
OBHT922A
4
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
(2) OPERATION
*The operating range of the outdoor unit depends on the connected outdoor unit.
Mode
Condition
Indoor
Intake air temperature (°F)
Outdoor
DB
WB
DB
WB
Standard temperature
80
67
95
—
Cooling
Maximum temperature Minimum temperature
90 67
73
115
57
14
— —
Maximum humidity Standard temperature Heating Maximum temperature Minimum temperature
78%
70
60
80
67
70
60
—
47
43
75
65
-13
-14
3-2. OUTLET AIR SPEED AND COVERAGE Multi connection
Model
Mode Function
Airflow (CFM)
HEAT
Dry
212
NTXUKS06A112AA COOL
Dry Wet
198 —
Air speed (ft./s.)
14.6
15.6
—
Coverage (ft.)
17.6
18.8
—
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.
OBHT922A
5
4
OUTLINES AND DIMENSIONS
NTXUKS06A112AA INDOOR UNIT
Unit: inch
(TLP-448W/ALP-448W)
OBHT922A
6
5
WIRING DIAGRAM
INDOOR UNIT NTXUKS06A112AA
NOTES : 1.About the outdoor side electric wiring
refer to the outdoor unit electric wiring diagram for servicing. 2.Use copper
conductors only. (For field wiring) 3.Symbols below indicate.
: Terminal block
: Connector
REMARQUES : 1.Pour le câblage électronique côté
extérieur, se reporter au schéma d’entretien du câblage électronique de
l’appareil extérieur. 2.Utiliser des fils d’alimentation en cuivre. 3.Les
symboles ont les significations suivantes
: Borne
: Connecteur
OBHT922A
7
6 REFRIGERANT SYSTEM DIAGRAM
INDOOR UNIT NTXUKS06A112AA
Refrigerant pipe ø3/8(ø9.52) (with heat insulator)
Indoor heat exchanger
Indoor coil thermistor RT12 (main)
Flared connection
Indoor coil thermistor RT13 (sub)
Unit: inch(mm)
Room temperature thermistor RT11
Flared connection
Refrigerant pipe ø1/4(ø6.35) (with heat insulator)
Refrigerant flow in cooling Refrigerant flow in heating
OBHT922A
8
SERVICE FUNCTIONS
NTXUKS06A112AA
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 9-7.) · 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.
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. 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.)
Table 1
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
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 OFF/ ON (stop/operate) 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.
OBHT922A
9
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. 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.)
C111
IC101
JR77
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 cancelled. · 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.
OBHT922A
10
7-4. P.C. BOARD MODIFICATION FOR CHANGING AIRFLOW VOLUME
Change Slide switch SW3 setting according to the height of ceiling.
Slide switch SW3
Normal
Increase airflow volume
Ceiling height
8.0 ft. (2.4 m) or below
above 8.0 ft. (2.4 m) and 9.0 ft. (2.7 m) or below
NOTE: When the ceiling is above 9.0 ft. (2.7 m), airflow volume may be
insufficient even with the Slide switch (SW3) set to “increase airflow”.
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 disp
cover 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 disp cover. NOTE: · Perform static
elimination before setting.
Electronic control P.C. board
Slide switch SW3
TB base Disp cover
Normal volume
7-5. P.C. BOARD MODIFICATION FOR CHANGING AIRFLOW DIRECTION ADJUSTMENT
The setting when the lower airflow is preferred in the Airflow direction (1)
The angle of airflow direction (1) can be slightly lowered by changing SWV1 to
normal when the lower airflow is preferred or the airflow causes the dirt on
the ceiling.
(AUTO) (1)
(2)
(3)
(4)
(5) (SWING)
How to change Dip switch (SWV1) setting (Factory setting is up)
1. Make sure that the breaker for air conditioner is turned OFF.
2. Remove the disp cover of the indoor unit.
3. Slide out the electronic control P.C. board, and change the slide switch (SWV1) to normal.
4. Put the electronic control P.C. board back to the original position, and install the disp cover.
NOTE:
· Perform static elimination before setting.
Electronic control P.C. board
Slide switch SWV1
OBHT922A
TB base Disp cover
Normal
Up
(Airflow direction
is lowered.)
11
MICROPROCESSOR CONTROL
NTXUKS06A112AA WIRELESS REMOTE CONTROLLER
Signal transmitting section Distance of signal: About 20 ft. (6 m) Beep(s) is
(are) heard from the indoor unit when the signal is received.
Operation display section Temperature buttons
Battery replacement indicator
Operation select button
OFF/ON (stop/operate) button
ECONO COOL button SLEEP button SMART SET button
Indication of remote controller model is on back
Operate the remote controller in the area where signal is received, and beep
is heard.
90°
FAN speed control button WIDE VANE control button VANE control button TIME,
TIMER set buttons Increase time Decrease time
WEEKLY TIMER set button
RESET button CLOCK button
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
The room temperature is approaching the set temperature
About 4°F(2°C) or more away from set temperature
About 2 to 4°F(1 to 2°C) from set temperature
Lit Blinking Not lit
Standby mode
(Refer to multi system
–
operation)
OBHT922A
12
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. 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 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.) 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 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
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 temperature 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”.
OBHT922A
13
NOTE 2 FOR MULTI SYSTEM AIR CONDITIONER OUTDOOR UNIT: MXZ series
Multi system air conditioner can connect 2 or more indoor units with one
outdoor unit. · When you try to operate 2 or more indoor units with one
outdoor unit simultaneously, one for the cooling and the others for heating,
the operation mode of the indoor unit that operates first is selected. Other
indoor units cannot operate, and operation indicator lamp blinks as shown in
the figure below. In this case, please set all the indoor units to the same
operation mode. OPERATION INDICATOR
Lit
Blinking
Not lit
· 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 flowing may be heard, they are not
malfunction. The reason is that the refrigerant continuously flows into it.
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.
(AUTO) (1)
(2)
(3)
(4)
(5) (SWING)
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 7-5. 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.
(4) VANE AUTO ( ) mode In VANE AUTO mode, the microprocessor automatically
determines the vane angle and operation to make the optimum room-temperature
distribution.
(1) In COOL and DRY operation
Vane angle is fixed to Angle 1.
1
(2) In HEAT operation
Vane angle is fixed to Angle 4.
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.
OBHT922A
14
(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.
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 OFF/ON
(stop/operate) button is pressed (POWER ON). (b) When SWING is started.
8-7. DRAIN PUMP CONTROL
1. Drain pump Operating condition: 1. During COOL, DRY, or emergency COOL
operation 2. When the drain sensor detects the water level above the fixed
point during the following states: (a) Standby during multi system operation
(b) Standby while the ON timer is set (c) Operation stop 3. When there is a
failure on the drain sensor
Drain pump operates in conditions 1,2 or 3.
Stop conditions: States other than 1 or 2 indicated above
OBHT922A
15
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
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 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.
PROGRAM TIMER
· 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.
(Example 1) The current time is 8:00 PM.
(Example 2) The current time is 11:00 AM.
The unit turns off at 11:00 PM, and on at 6:00 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 cancelled. As these models are equipped with an auto restart function, the air conditioner starts operating with timer cancelled when power is restored.
OBHT922A
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8-9. 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.
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.
Mon
Setting1
ON
Setting2 OFF
~
75°F (24°C)
Fri
AM 6:00
AM 8:30
Setting1 Sat
ON
~
Sun
AM 8:00
Setting3
Setting4
ON
OFF
81°F (27°C)
PM 5:30
PM 10:00
81°F (27°C)
Setting2 OFF
PM 9:00
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
- Make sure that the current time and day are set correctly.
(1) Press
button to enter the weekly timer setting mode.
blinks.
(2) Press
and
buttons to select setting days and/or numbers.
E.g. : [Mon Tue … Sun] and [1] are selected.
Pressing
selects the day of
the week to be set.
Pressing
selects
the setting number.
- All days can be selected.
(3) Press
, , and buttons to set ON/OFF, time, and temperature.
E.g. : [ON], [6:00] and [75°F(24°C)] are selected.
Pressing selects ON/OFF timer.
Pressing
Pressing
Pressing deletes timer setting.
adjusts the time.
adjusts the temperature.
- 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.
OBHT922A
17
(4) Press
button to complete and transmit the weekly timer setting.
which was blink-
ing goes out, and the
current time will be
displayed.
NOTE:
· Press
button to transmit the setting information of weekly timer to the indoor unit. Point the remote controller toward the
indoor unit for 3 seconds.
· When setting the timer for more than one day of the week or one number,
button does not have to be pressed per each
setting. Press
button once after all the settings are complete. All the weekly timer settings will be saved.
· Press
button to enter the weekly timer setting mode, and press and hold
button for 5 seconds to erase all weekly
timer settings. Point the remote controller toward the indoor unit.
(5) Press button to turn the weekly timer ON. ( lights.)
·When the weekly timer is ON, the day of the week whose timer setting is complete, will light.
Press button again to turn the weekly timer OFF. ( goes out.)
NOTE: The saved settings will not be cleared when the weekly timer is turned OFF.
2. Checking weekly timer setting
(1) Press
button to enter the weekly timer setting mode.
- blinks.
(2) Press
or
buttons to view the setting of the particular day or number.
(3) Press
button to exit the weekly timer setting.
8-10. SMART SET ( ) OPERATION
1. How to set SMART SET operation (1) Press OFF/ON (stop/operate) button. (2)
Select COOL or HEAT mode. (3) Press SMART SET button. (4) Set the temperature,
fan speed, and airflow 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 OFF/ON (stop/operate) button. (2)
Select COOL, DRY, HEAT or FAN mode.
(3) Press SLEEP (
) button.
(4) PRESS Temperature buttons [ operation.
(Increase) and
(Decrease) ] to set the temperature of SLEEP
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 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.
Set temperature for the operation before SLEEP operation
Set temperature for SLEEP operation
Set temperature for the operation before SLEEP operation
For about 30 minutes
NOTE:
· ON/OFF timer is available during SLEEP operation. · When a preset ON time
for the weekly timer becomes 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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8-12. EMERGENCY/TEST OPERATION In the case of test run operation or emergency
operation, use the emergency operation switch on the right side of the indoor
unit. Emergency operation is available when the remote controller is missing
or has failed, or 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 emergency operation, the horizontal
vane operates in VANE AUTO ( ) mode. Emergency operation continues until the
emergency operation switch is pressed once or twice or the unit receives any
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 indicator lamp
Remote control receiving section
Emergency operation switch
Operation mode COOL/HEAT
Set temperature 75°F(24°C)
Fan speed Horizontal vane
Medium Auto
The operation mode is indicated by the Operation Indicator lamp as following
Operation Indicator lamp
EMERGENCY COOL
EMERGENCY HEAT
STOP
Lit Not lit
8-13. 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.
8-14. 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 while the Temperature buttons
are pressed.
Press RESET button gently using a fine-tipped object.
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9
TROUBLESHOOTING
NTXUKS06A112AA
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 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
electronic control P.C. board. 3) When removing the electronic control 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.
Lead wiring
Connector housing
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 OPERATIONAL INDICATOR lamp is blinking ON and OFF before starting
service work.
-
Before servicing, verify that all connectors and terminals are connected properly.
-
When the electronic control P.C. board seems to be defective, check for disconnection of the copper foil pattern and
burnt or discolored components.
- 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.
Remove the front lid and insert batteries.
Press RESET button with a fine-tipped object, and
Then reattach the front lid.
then use the remote controller.
Insert the negative pole of the batteries first. Check if the polarity of the batteries is correct.
RESET button
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 microprocessor when batteries are replaced. This function is equipped to prevent the microprocessor from malfunctioning due to the voltage drop caused by the battery replacement. 3. Do not use the leaking batteries.
INFORMATION FOR MULTI SYSTEM AIR CONDITIONER
OUTDOOR UNIT : MXZ series
Multi system air conditioner can connect two or more indoor units with one
outdoor unit. · Unit will not operate in case the total capacity of indoor
units exceeds the capacity of outdoor units. Do not connect indoor
units beyond the outdoor unit capacity. Operation indicator lamp blinks as
shown in the figure below. · When you try to operate 2 or more indoor units
with one outdoor unit simultaneously, one for the cooling and the other for
heating, the operation mode of the indoor unit that operates earlier is
selected. The other indoor units cannot operate and indicate as shown in the
figure below. In this case, please set all the indoor units to the same
operation mode.
OPERATION INDICATOR
Lit
Blinking
Not lit
· When indoor units start operation while the defrosting of outdoor unit is
being done, it takes a few minutes (maximum 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 flowing may be heard, they are not
malfunction. The reason is that the refrigerant continuously flows into it.
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9-2. 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 (9-4.) disappears, the
memorized failure details can be recalled.
1. Flow chart of failure mode recall function for the indoor/outdoor unit
Operational procedure
The cause of abnormality cannot be found because the abnormality does not
recur.
Setting up the failure mode recall function Turn ON the power supply.
Press OFF/ON (stop/operate) button of the remote controller (the set temperature is displayed) with the remote controller headed towards the indoor unit.*1
*1 Regardless of normal or abnormal condition, a short beep is emitted once the signal is received.
Does the left lamp of OPERATION INDICATOR lamp on the indoor unit blink at the
interval of 0.5 seconds? Blinks: Either indoor or outdoor unit is abnormal.
Beep is emitted at the same timing as the blinking of the left lamp of
OPERATION INDICATOR lamp. *2
Judgment of indoor/outdoor abnormality
Yes (Blinks)
Before blinking, does the 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.
No
No (OFF)
Yes
The indoor unit is abnormal. Check the blinking pattern, and identify the abnormal point by referring to the table of indoor unit failure mode recall function. (Refer to 9-2.3) Make sure to check at least 2 consecutive blinking cycles. *2
Indoor unit is normal. But the outdoor unit might be abnormal because there
are some abnormalities that cannot be recalled with this way. Check if outdoor
unit is abnormal according to the detailed outdoor unit failure mode recall
function.
NOTE: It takes up to 1 minute to indicate the outdoor unit abnormality. Even
if the OPERATION INDICATOR lamp is not lighting, keep checking at least 1
minute or longer.
The outdoor unit is abnormal. Check the blinking pattern, and identify the
abnormal point by referring to the table of outdoor unit failure mode recall
function. (Refer to outdoor unit service manual.) Make sure to check at least
2 consecutive blinking cycles. *3
Releasing the failure mode recall function
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.
Repair the failure parts.
Deleting the memorized abnormal condition
After repairing the unit, recall the failure mode again according to “Setting
up the failure mode recall function” mentioned above.
Press OFF/ON (stop/operate) button of the remote controller (the set
temperature is displayed) with the remote controller headed towards the indoor
unit. Press the emergency operation switch so that the memorized abnormal
condition is deleted. *4 Release the failure mode recall function according to
“Releasing the failure mode recall function” mentioned above.
*4 The information regarding whether the connected outdoor unit is a low-standby-power model or a nonlow-standby-power model will also be initialized. (Default= compatible with a low-standby-power model)
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.
*2. Blinking pattern when the indoor unit is abnormal:
ON OFF
Blinking at 0.52.5-second OFF second interval
Blinking at 0.52.5-second OFF second interval
Beeps Repeated cycle
Beeps Repeated cycle
Beeps Repeated cycle
*3.Blinking pattern when the outdoor unit is abnormal:
Blinking at 0.5-
2.5-second OFF 3-second ON
second interval
ON OFF
No beep Repeated cycle
Beeps
2.5-second OFF 3-second ON
Blinking at 0.5second interval
No beep Repeated cycle
Beeps
Repeated cycle
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2. Flow chart of the detailed outdoor unit failure mode recall function
Operational procedure
The outdoor unit might be abnormal. Check if outdoor unit is abnormal
according to the following procedures.
Make sure that the remote controller is set to the failure mode recall
function.
With the remote controller headed towards the indoor unit, press TOO COOL or
TOO WARM button to adjust the set temperature to 77ºF (25ºC). *1
*1. Regardless of normal or abnormal, 2 short beeps are emitted as the signal is received.
Does OPERATION INDICATOR lamp on the indoor unit blink at the interval of 0.5
seconds? Blinks: The outdoor unit is abnormal.
Beeps are emitted at the same timing as the blinking of OPERATION INDICATOR
lamp. *2
No (OFF)
Yes (Blinks)
The outdoor unit is abnormal. Check the blinking pattern, and identify the
abnormal point by referring to the table of outdoor unit failure mode recall
function (Refer to outdoor unit service manual). Make sure to check at least 2
consecutive blinking cycles. *2
Releasing the failure mode recall function
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 normal.
Release the failure mode recall function according to the left mentioned
procedure.
Repair the failure parts.
Deleting the memorized abnormal condition After repairing the unit, recall the
failure mode again according to “Setting up the failure mode recall function”.
Press OFF/ON (stop/operate) button of the remote controller (the set
temperature is displayed) with the remote controller headed towards the indoor
unit. Press the 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”.
Note1. 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.
*2.Blinking pattern when outdoor unit is abnormal:
ON OFF
2.5-second OFF 3-second ON
No beep Repeated cycle
Blinking at 0.5second interval
Beeps
2.5-second OFF 3-second ON
Blinking at 0.5second interval
No beep Repeated cycle
Beeps
Repeated cycle
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3. Table of indoor unit failure mode recall function
NOTE: Blinking patterns of this mode differs from the ones of Troubleshooting check table (9-4.).
Left lamp of
Right lamp of
OPERATION
OPERATION
INDICATOR lamp INDICATOR lamp
Abnormal point (Failure mode)
Not lit
Not lit
Normal
Condition —
Remedy —
1-time blink every 0.5-second
Not lit
Room temperature thermistor
When the room temperature thermistor short or open circuit is detected every 8 seconds during operation.
Refer to the characteristics of the room temperature thermistor (9-7.).
2-time blink 2.5-second OFF
Not lit
Indoor coil thermistor (Main 1, 2 and sub)
When the indoor coil thermistor short or open circuit is detected every 8 seconds during operation.
Refer to the characteristic of the main 1,2 indoor coil thermistor and the sub indoor coil thermistor (9-7.).
3-time blink 2.5-second OFF
Not lit
5-time blink 2.5-second OFF
Not lit
11-time blink 2.5-second OFF
Not lit
12-time blink 2.5-second OFF
Not lit
Serial signal error
Drain pump Drain sensor
Indoor fan motor Indoor control system
When the serial signal from the outdoor unit is not received for a maximum of 6 minutes.
Refer to 9-6. “How to check miswiring and serial signal error”.
· Check the drain sensor and the drain
· Drain sensor is open.
· Drain sensor detects abnormal water level.
pump.
· Check the connectors of drain sensor and the drain pump.
· Refer to 9-6. “Check of drain sen-
sor and drain pump”.
When the rotational frequency feedback signal is not emitted during 12 seconds the indoor fan operation.
Refer to 9-6. “Check of indoor fan motor”.
When 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.
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9-3. INSTRUCTION OF TROUBLESHOOTING
Start
Indoor unit operates. Outdoor unit does not operate.
Indoor unit operates. Outdoor unit does not operate normally.
Indoor unit does not receive the signal from remote controller.
OPERATION INDICATOR lamp on the indoor unit is blinking on and off.
Outdoor unit operates only in Test Run operation.
*1
Outdoor unit does not operate even in Test Run operation.
*1
Unit does not operate normal operation in COOL or HEAT mode.
Indoor unit operates when the emergency operation switch is pressed.
Indoor unit does not operate when the emergency operation switch is pressed.
Check room temperature thermistor. Refer to 9-7. “TEST POINT DIAGRAM AND VOLTAGE”.
Refer to “How to check inverter/ compressor”.
Refer to “Check of R.V. coil”.
Refer to 9-6. “Check of remote controller, receiver P.C. board and indoor electronic control P.C. board”.
1. Check indoor/outdoor connecting wire. (Check if the power is supplied to
the indoor unit.)
2. Refer to 9-6. “Check of indoor electronic control P.C. board and indoor
fan motor”.
If blinking of OPERATION INDICATOR lamp cannot be checked, it can be checked
with failure mode recall function.
*1 “Test Run operation” means the operation within 30 minutes after the emergency operation switch is pressed.
Refer to outdoor unit service manual.
Left lamp Blink on and off at 0.5-second intervals Cause: Indoor/ Outdoor unit · Mis-wiring or trouble of serial signal
Left lamp 2-time blink Cause: Indoor unit · Trouble of
room temperature/ indoor coil thermistor
Left lamp 3-time blink Cause: Indoor unit · Trouble of
indoor fan motor
Left lamp 4-time blink Cause: Indoor unit · Trouble of
indoor unit control system
Left lamp 5-time blink Cause:
Outdoor unit · Outdoor
power system abnormality
Left lamp 6-time blink Cause:
Outdoor unit · Trouble of
thermistor in outdoor unit
Left lamp 7-time blink Cause:
Outdoor unit · Trouble of
outdoor control system
Left lamp 9-time blink Cause:
Indoor unit · Trouble of
drain sensor or drain pump
Left lamp 14-time blink or more Cause:
Outdoor unit · Other
abnormality · Check the
stop valve.
Refer to 9-6. Check room
“How to
temperature
check
thermistor
miswiring
and indoor
and serial
coil thermis-
signal error tor.
(when
Refer to 9-7.
outdoor unit
“Test point
does not work)”. diagram and
voltage”.
Refer to 9-6. “Check of
indoor fan motor”.
Replace the indoor electronic control P.C. board.
Refer to “How to check the inverter/ compressor”.
Refer to “Check of outdoor thermistors”.
Replace the inverter P.C. board or the outdoor electronic control P.C. board.
Refer to 9-6. “Check of
drain sensor and drain pump”.
Check the drain pump.
Check “Flow chart of the detailed outdoor unit failure mode recall function.”
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9-4. TROUBLESHOOTING CHECK TABLE
OPERATION INDICATOR
Lit Blinking
· Blinking of OPERATION INDICATOR lamp (left-hand side lamp) indicates abnormalities.
Not lit
NOTE: Before taking measures, make sure that the symptom reappears for accurate troubleshooting. Self check table
No.
Abnormal point
Operation indicator lamp
Symptom
Condition
Remedy
Miswiring 1 or serial
signal
Left lamp blinks. 0.5-second ON
0.5-second OFF
Indoor unit and outdoor unit do not operate.
· Refer to 9-6. “How to check
When the serial signal from the outdoor unit is miswiring and serial signal
not received for a maximum of 6 minutes.
error”.
Indoor coil Left lamp blinks. thermistor 2-time blink
2
Room temperature thermistor
2.5-second OFF
Indoor unit and outdoor unit do not operate.
When the indoor coil or the room temperature thermistor is shorts or opens circuit.
· Refer to the characteristics of indoor coil thermistor, and the room temperature thermistor on 9-7.
Left lamp blinks.
3-time blink
3
Indoor fan motor
2.5-second OFF
Indoor unit and outdoor unit do not operate.
When the rotational frequency feedback signal is not emitted during the indoor fan operation.
· Refer to 9-6. “Check of indoor fan motor”.
Indoor 4 control
Left lamp blinks. 4-time blink
system
2.5-second OFF
Outdoor 5 power
system
Left lamp blinks. 5-time blink
2.5-second OFF
Left lamp blinks. 6-time blink
6 Outdoor thermistors
2.5-second OFF
Outdoor 7 control
system
Left lamp blinks. 7-time blink
2.5-second OFF
Drain 8 pump
Left lamp blinks. 9-time blink
2.5-second OFF
Left lamp blinks. 14-time blink or more 9 Other abnormality
2.5-second OFF
Indoor unit and outdoor unit do not operate.
When 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.
Indoor unit and outdoor unit do not operate.
Indoor unit and outdoor unit do not operate.
The compressor stops 3 times consecutively for over current protection or
start-up failure protection within 1 minute after start-up.
When the outdoor thermistors short or open circuit during the compressor
operation.
· Refer to “Check of inverter/ compressor”.
· Check the stop valve. Refer to outdoor unit service manual.
· Refer to “Check of outdoor thermistor”. Refer to outdoor unit service
manual.
Indoor unit and outdoor unit do not operate.
Indoor unit and outdoor unit do not operate.
Indoor unit and outdoor unit do not operate.
When it cannot properly read data in the nonvolatile memory of the inverter
P.C. board or the outdoor electronic control P.C. board.
· Drain sensor is open. · Drain sensor detects abnormal water level.
· Replace the inverter P.C. board or the outdoor electronic control P.C.
board. Refer to outdoor unit service manual.
· Check the drain sensor characteristics.
· Check the drain pump. · Check the drain pipe. · Check the connectors of
drain
sensor and the drain pump. · Refer to 9-6. “drain sensor
and drain pump”.
An abnormality other than above mentioned is detected.
· Check the abnormality in detail using the failure mode recall function. Refer to outdoor unit service manual.
NOTE: When the indoor unit has started operation and the above failures are detected (the first detection after the power ON), the indoor electronic control P.C. board turns OFF the indoor fan motor with OPERATION INDICATOR lamp blinking.
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OPERATION INDICATOR
Lit Blinking Not lit
· Blinking of OPERATION INDICATOR lamp (right-hand side lamp) indicates
abnormality.
· OPERATION INDICATOR lamp (left-hand side lamp) is lighted.
No.
Abnormal point
MXZ type
1
Operation mode
setting
Operation indicator lamp Right lamp blink
2.5-second OFF
Symptom
Outdoor unit operates but indoor unit does not operate.
Condition
When the operation mode of the each indoor unit is differently set to COOL
(includes DRY) and HEAT at the same time, the operation mode of the indoor
unit that has operated at first has the priority.
Remedy
· Unify the operation mode. Refer to outdoor unit service manual.
NOTE: When the indoor unit has started operation and the above failures are detected (the first detection after the power ON), the indoor electronic control P.C. board turns OFF the indoor fan motor with OPERATION INDICATOR lamp blinking.
9-5. TROUBLESHOOTING CRITERION OF MAIN PARTS
NTXUKS06A112AA
Part name
Check method and criteria
Room temperature thermistor (RT11)
Measure the resistance with a multimeter. (Part temperature 10°C – 30°C)
Indoor coil thermistor (RT12 (MAIN), RT13 (SUB))
Normal 8 k – 20 k
Figure
Indoor fan motor
Drain sensor (DS)
Connection
CN1N1 connector 1 BLK 1 1 BLK
2 BLK 3 BLK 4 BLK
2 3
2 3
BLK GRY
4 4 GRY
5
6
7
Drain pump (DP)
Horizontal vane motor (MV1)
Vertical vane motor (MV2)
Check 9-6. .
Disconnect the connectors and measure the resistance between the terminals with a multimeter. (Part temperature 10°C – 30°C)
Terminal (CN1M1)
Normal
Abnormal
BLK -BLK (heater) BLK -BLK (thermistor)
About 80 4k – 10k
Open or short
NOTE: The relay connectors are connected near the drain sensor. (Refer to characteristic graph 9-7.)
Measure the resistance between the terminals with a multimeter. (Part temperature 10ºC – 30ºC)
Color of the lead wire BLUE-BLUE (Drain pump side) RED-RED (Control P.C. board side)
Normal 520 – 620
Measure the resistance between the terminals with a multimeter. (Part temperature 20ºC – 30ºC)
Color of the lead wire
Normal
RED-YLW
Each phase 300
Measure the resistance between the terminals with a multimeter. (Part temperature 20ºC – 30ºC)
Color of the lead wire
Normal
RED-YLW
Each phase 300
YLW
YLW RED
ROTOR YLW YLW
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9-6. TROUBLESHOOTING FLOW
When the left lamp of OPERATION INDICATOR lamp blinks 3 times and the right
lamp of OPERATION INDICATOR lamp is not lighted. Indoor fan does not operate.
A Check of indoor fan motor
The indoor fan motor error has occurred, and the indoor fan does not operate.
Turn OFF the power supply.
Is there anything that interferes the
rotation of the line flow fan?
No
Yes
Remove the object and adjust the line flow fan.
Pay attention to the high voltage on the fan motor connector CN211.
Turn ON the power supply, wait 5 seconds or more, and then press the emergency
operation switch. Measure the supply voltage as follows within 12 seconds
after the emergency operation switch is pressed. If more than 12 seconds
passes by, turn OFF the power supply and turn ON it again, then measure the
voltage. * 1) Measure the voltage between CN211 (+) and (-). 2) Measure the
voltage between CN211 (+) and (-).
- If more than 12 seconds pass after the emergency operation switch is pressed, the voltage mentioned in above 2) goes 0 V DC although the indoor electronic control P.C. board is normal.
Is there 294/325 V DC
between CN211 (+)
and ()?
Yes
No
Does the voltage between CN211 (+) and () on the indoor electronic control
P.C. board rise to the range of 3 to 6 V DC within 12 seconds after Yes the
emergency operation switch is pressed?
No
Replace the indoor fan motor.
Replace the indoor electronic control P.C. board. The indoor fan motor error has occurred, and the indoor fan repeats “12-second ON and 30-second OFF” 3 times, and then stops.
Measure the voltage between CN211 (+) and (-) while the fan
motor is rotating.
Indoor electronic control P.C. Board
C111
Is 0 V DC or 15 V DC
held unchanged?
No
(Changed) Yes
(Unchanged)
Replace the indoor electronic control P.C. board.
Replace the indoor fan motor.
CN211
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Indoor unit operates by pressing the emergency operation switch, but does not
operate with the remote controller.
B Check of remote controller, receiver P.C. board and indoor electronic
control P.C. board
- Check if the remote controller is exclusive for this air conditioner.
Press OFF/ON (stop/operate) button on the remote controller.
Is LCD display on the remote controller visible?
Yes
Replace the batteries. (Refer to 9-1.4.) No (Not clear)
Remove the batteries, then set them back and press RESET button. (Refer to 9-1.4.) Check if the unit operates with the remote controller.
Does the unit operate with the
remote controller?
No
Yes
Assign a number of remote controller. (Refer to 7-2.) Check if the unit operates with the remote controller.
1 Look at the image of the signal transmitting section of the remote controller through the monitor of a digital camera or a camera phone. It is normal if the LED of the signal transmitting section lights up when the OFF/ON (stop/operate) button on the remote controller is pressed. However, it may be difficult to see the illuminated LED of the signal transmitting section with a smartphone camera.
2 If the inverter fluorescent light is turned on when the room is cool, the unit may have difficulty receiving the signal from the remote controller or may not be able to operate with it; if the inverter fluorescent light is turned on when the room is warm, the unit may be able to operate with the remote controller.
OK
Does the unit operate with
the remote controller?
No
Turn ON a radio to AM and press OFF/ON (stop/operate) button on the remote controller. *1
Yes
OK
Receiver P.C. Board
Is noise heard from radio? Yes
Replace the remote controller. No
Are there any fluorescent lights of inverter or rapid-start type within the
range of 3.28 ft. (1 m)? *2 Yes
No
·Reinstall the unit away from lights. ·Attach a filter on receiving part.
Measure the voltage between receiver P.C. board connector CN301 (+) and (-) when the remote controller button is pressed.
CN301
Is the voltage approximately 4 V DC – 5 V DC? No
Replace the indoor electronic Yes control P.C. board.
Replace the receiver P.C. board.
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The unit cannot be operated with the remote controller. Also, OPERATION
INDICATOR lamp does not light up by pressing the emergency operation switch.
C Check of indoor electronic control P.C. board and indoor fan motor
Turn OFF the power supply. Remove indoor fan motor connector CN211 and vane motor connector CN151 from the indoor electronic control P.C. board and turn ON the power supply.
Turn OFF the power supply. Measure the resistance between CN211
and of the indoor fan motor connector.
Short/ open circuit: Replace the indoor fan motor.
Yes
Does the unit operate with the remote controller? Does OPERATION INDICATOR lamp light up by pressing the emergency operation switch?
Turn OFF the power supply. Measure the resistance of the horizontal vane motor coil and the vertical vane motor coil. Refer to 9-5.
No
Short/ open circuit: Replace the horizontal vane motor, the vertical vane motor coil and the indoor electronic control P.C. board.
Turn OFF the power supply. Check both “parts side” and “pattern side” of the indoor electronic control P.C. board visually.
Replace the varistor (NR11) and fuse (F11).
Yes
Are the varistor (NR11) burnt and the fuse (F11) blown? No
Be sure to check both the fuse and the varistor in any case.
Is the fuse (F11) blown only? No
Yes
Measure the resistance between (+) and (-) of the indoor fan
motor connector (to CN211 on the indoor electronic control P.C. board). 1, 2
1. The fan motor connector’s lead wire is red, whereas is black.
2. Connect “+” of the tester to fan motor connector’s lead wire, and “-” to lead wire, otherwise the resistance cannot be measured properly.
Is the resistance 1M or more?
Yes
Replace the fuse (F11).
No Replace the fuse (F11) and the indoor fan motor.
Measure the cement resistance R111 on the indoor electronic control P.C. board.
Is the resistance approximately 4?
Yes
Replace the indoor electronic control P.C. board No and the indoor fan motor.
Replace the indoor electronic control P.C. board.
Indoor electronic control P.C. Board R111
C111
Fuse (F11) VARISTOR (NR11)
CN211 CN151
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When the left lamp of OPERATION INDICATOR lamp blinks ON and OFF in every
0.5-second. Outdoor unit does not operate.
D How to check miswiring and serial signal error
Turn OFF the power supply.
Is there rated voltage of
208/230 V AC in the power
supply?
No
Yes
Turn ON the power supply.
Is there 208/230 V AC between
outdoor terminal block S1 and
S2?
No
Yes
Press the emergency operation switch once.
Check the power supply.
Check the wiring.
Does the left lamp of OPERATION INDICATOR
lamp light up?
No
Yes
Is the serial signal error indicated 6 minutes later? No
Yes
Is there any miswiring,
poor contact, or wire
disconnection of the
indoor/outdoor
Yes
connecting wire?
No
Correct them.
· Turn OFF inverter-controlled lighting equipment. · Turn OFF the power supply and then turn it ON again. · Press the emergency operation switch.
Is the serial
signal error
indicated 6
No
minutes later?
Yes
· Reinstall either the unit or the light away from each other.
· Attach a filter on receiving section of the indoor unit.
Turn OFF the power supply. Check once again if the indoor/outdoor connecting wire is not wrongly connected. Short-circuit the outdoor terminal block S2 and S3. *1
*1. Miswiring may damage indoor electronic control P.C. board during operation. Be sure to confirm the wiring is correct before the operation starts.
As for outdoor unit, refer to outdoor unit service manual.
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When the left lamp of OPERATION INDICATOR lamp blinks 9-time. Indoor unit and
outdoor unit do not operate.
E Check of drain sensor and drain pump
The drain sensor error has occurred.
Replace the drain sensor.
Yes
Are the relay connectors of the drain sensor (near the drain
No
Connect the
sensor) connected?
relay connectors.
Turn off the power supply and check the connectors CN1M1 and CN1N1 visually.
Are the lead wires No disconnected?
Yes
Connect the lead wires.
Are there any failures
at soldering parts of the connectors?
No
Yes
Disconnect the drain sensor from the CN1M1 on the indoor electronic control P.C. board. Measure the resistance between and , and .
No
Is the resistance about 80 between and ? Or is the resistance in the range of
about 4 to 10 k between and ?
Yes
Replace the indoor electronic control P.C. board.
Indoor electronic control P.C. board
Is there large amount of water in the drain pan?
Yes
No Replace the indoor electronic
control P.C. board.
C111
CN1N1 CN1M1
Connector to drain pump Connector to drain sensor
Turn on the power and press the emergency operation switch (COOL) to start COOL operation. Measure the voltage between and of the CN1N1 on the indoor electronic control P.C. board.
Is the voltage
No
208/230 V AC?
Connect the relay connectors.
No Are the relay connectors of the drain pump (near the drain pump) connected?
Yes
No
Is the drain pump
operating?
Yes
*2 Refer to 9-5. when the
*2
Yes
drain pump can be checked. Replace the
drain pump.
Is the drain pump clogged?
No
Replace the drain pipe.
Yes
Does the drain hose (the lifting height and the gradient) follow
the specification?
Yes
No Is the drain hose
Yes
clogged?
Yes Replace the drain pump. Replace the indoor electronic control P.C. board.
Check the power supply voltage. Replace the indoor electronic control P.C.
board.
Remove clogs from the drain hose.
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F Electromagnetic noise enters into TV sets or radios
Is the unit grounded? Yes
No
Ground the unit.
Is the distance between the antennas and the indoor unit within 9.91 ft. (3m),
or is the distance between the antennas Yes and the outdoor unit within 9.91
ft. (3m)?
No
Extend the distance between the antennas and the indoor unit, and/or the antennas and the outdoor unit.
Is the distance between the TV sets or ra-
dios and the indoor unit within 3.28 ft. (1m), or is the distance between the TV sets or
radios and the outdoor unit within
Yes
9.91 ft. (3m)?
No
Are the antennas damaged? Is the coaxial cable damaged? Is there any poor
contact in the anten- Yes na wiring?
No
Is the indoor/outdoor connecting wire
of the air conditioner and the wiring of
the antennas close?
Yes
No
Extend the distance between the TV sets and/ or radios and the indoor unit, or
the TV sets or radios and the outdoor unit.
Replace or repair the antenna. Replace or repair the coaxial cable.
Extend the distance between the indoor/outdoor connecting wire of the air
conditioner and the wiring of the antennas.
Even if all of the above conditions are fulfilled, the electromagnetic noise
may enter, depending on the electric field strength or the installation
condition (combination of specific conditions such as antennas or wiring).
Check the following before asking for service. 1. Devices affected by the
electromagnetic noise
TV sets, radios (FM/AM broadcast, shortwave) 2. Channel, frequency, broadcast
station affected by the electromagnetic noise 3. Channel, frequency, broadcast
station unaffected by the electromagnetic noise 4. Layout of:
indoor/outdoor unit of the air conditioner, indoor/outdoor wiring, ground
wire, antennas, wiring from antennas, receiver 5. Electric field intensity of
the broadcast station affected by the electromagnetic noise 6. Presence or
absence of amplifier such as booster 7. Operation condition of air conditioner
when the electromagnetic noise enters in
- Turn OFF the power supply once, and then turn ON the power supply. In this situation, check for the electromagnetic noise.
- Within 3 minutes after turning ON the power supply, press OFF/ON (stop/operate) button on the remote controller for power ON, and check for the electromagnetic noise.
- After a short time (3 minutes later after turning ON), the outdoor unit starts running. During operation, check for the electromagnetic noise.
- Press OFF/ON (stop/operate) button on the remote controller for power OFF, when the outdoor unit stops but the indoor/outdoor communication still runs on. In this situation, check for the electromagnetic noise.
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9-7. TEST POINT DIAGRAM AND VOLTAGE
NTXUKS06A112AA
Indoor electronic control P.C. board CN1N1
R111
Connector to drain pump
Factory setting (Do not change the setting.)
SW101
ON
CN202 Serial signal
1 2 3 4 5 6 OFF
NR11 Varistor
F11 FUSE T3.15AH250V
CN201 Power supply input 208/230 V AC CN1M1 Connector to drain sensor
T3.15AH250V
CN111 Room temperature thermistor RT11
CN105 Connector to optional interface
5 V DC
CN211 Indoor fan motor
294/325 V DC (-) GND (High voltage DC) 15 V DC (+) 3 – 6 V DC (+) 0 or 15 V DC
CN112 Indoor coil thermistor RT13 (SUB) Indoor coil thermistor RT12 (MAIN 1)
} JR05 Modifica-
JR06
tion point for
individual
operation
(Refer to
7-2.)
CN106 Connector to display P.C. board
12 V DC CN151 Vane motor connector Receiver P.C. board
CN1J1
CN109
GND
Connector to display
Connector to
P.C. board
receiver P.C. board
SWV1
To disable “Auto restart function”, cut the Jumper wire to JR77. (Refer to 7-3.)
Timer short Changing air-
mode point flow direction
(2 points)
(Refer to 7-5.)
(Refer to 7-1.)
Dip switch SW3 (Increase air flow volume) (Refer to 7-4.)
Indoor coil thermistor [RT12 (MAIN), RT13 (SUB)] Room temperature thermistor (RT11)
CN301 Indoor electronic control P.C. board connector
Drain sensor thermistor 20
15
Display P.C. board
10
Resistance (k) Resistance (k)
CN302 Indoor electronic control P.C. board connector
SW301 Emergency operation switch
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Temperature (ºC)
5
0 0 10 20 30 40 50 60 70 Temperature (ºC)
DISASSEMBLY INSTRUCTIONS
(1) Slide the sleeve and check if there is a locking lever or not.
Sleeve
(2) The terminal with the connector shown below has the locking mechanism.
Locking lever
Slide the sleeve. Pull the terminal while pushing the locking lever.
NTXUKS06A112AA
NOTE: Turn OFF the power supply before disassembly.
OPERATING PROCEDURE
Hold the sleeve, and pull out the terminal slowly.
Connector
: Indicates the visible parts in the photos/figures. : Indicates the invisible
parts in the photos/figures.
PHOTOS/FIGURES
1. Removing the intake grille (1) Slide the tabs (2 places) of intake grille in the direction of the arrow (Figure 1). (2) Hold the intake grille and pull it down to open (Figure 2). (3) Slide the grille shafts (1 each on the left and right sides) off the intake grille and remove the intake grille (Figure 3). (4) Remove the safety strings of intake grille from the hooks (Figure 4).
Photo 1
Remote control receiving section
Places for installing the air cleaning filter. [Anti-allergy Enzyme Filter (option)] [Install to air filters.(Air purifying filter)] Horizontal vane
Figure 1
Intake grille
Electrical parts Safety string
Safety string Intake grille
Figure 2
Places for installing the air filter(Air purifying filter)
Figure 3
Tab Press
Slide inward.
Shaft
Figure 4
Safety string
Hook
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OPERATING PROCEDURE
2. Removing the grille (1) Remove the intake grille. (2) Remove the fixing
screws for side panels (2 screws) on the left and right sides (Figure 5). (3)
Open the side panels on the left and right sides. Remove the safety strings
from the grille and remove the side panels (Figure 5). (4) Open the horizontal
vane completely. (5) Remove the screw cap in the center of air outlet (Figure
5). (6) Remove the fixing screws at 4 places on the left and right sides
(Figure 6). (7) Remove the fixing screws at 2 places in the middle and the
fixing screw in the center (Figure 6). (8) Remove the temporary holding tabs
of the grille from the hooks of the indoor unit (Figure 6).
Figure 5
PHOTOS/FIGURES
Side cover fixing screw
Slide inward.
Shaft
Side cover fixing screw
Side cover Screw cover safety string
Intake grille safety strings
Figure 6 Hook
Hook
Temporary holding tab
Temporary holding tab
Figure 7
Screw cover
Indoor unit
Ceiling surface
No gaps here Grille
Figure 8 Fixing screw
Nuts for hanging the indoor unit are adjustable from this opening by using general tools such as a spanner. (Same for the other side)
Fixing screw
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OPERATING PROCEDURE
(7) Install the screw cap. (8) After attaching the safety strings for the left
and right
side panels to the grille, install the side panels (Figure 9). NOTE: Make sure
that the tabs of the side panels securely fit
into place (Figure 9).
NOTE: Open the display cover to make sure the positioning marks are aligned.
NOTE: Make sure that there are no gaps between the emergency operation switch
and the side panel (Figure 10).
NOTE: Make sure that the safety strings do not hang out of the side panels.
(9) Attach the air cleaning filters (Anti-allergy Enzyme Filter), if any, to
the catches on the air filters(Air purifier filters) (Figure 10).
(10) Attach the safety strings for intake grille to the grille and insert the
grille shafts into the holes of the intake grille (Figure 10).
(11) Close the intake grille (Figure 11).
NOTE: Press the intake grille firmly against the grille until a click is heard
from each tab on the left and right sides.
PHOTOS/FIGURES
Figure 9
Side cover safety string
Side cover
Attach to the hook on the grille. Hook for engaging catch
Hooks for engaging catches (3 positions)
Hook for engaging catch
Figure 10
Attach to the hook on the grille.
Intake grille safety string
Figure 11
Press 3 points.
Hooks
Shaft Insert
Intake grille Hooks Anti-allergy Enzyme Filter
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OPERATING PROCEDURE
3. Removing the indoor electric control P.C. board, the receiver P.C. board
and the display P.C. board (1) Remove the intake grille. (2) Remove the side
panel (L). (3) Remove screw of the lampcover and Pull out a cover to the
direction of an arrow. (Photo 2). (4) Remove the electrical cover (Photo 2).
(5) Partially slide the indoor electronic control P.C. board out. (6)
Disconnect all the connectors and lead wires on the board to remove the indoor
electric control P.C. board. (7) Disconnect the connectors and lead wires, and
remove the receiver P.C. board and the display P.C. board.
PHOTOS/FIGURES
Photo 2
Fixing screw of the electrical box
Fixing screws of the lamp cover
Drain pan
Lamp cover
Electrical cover
4. Removing the heat exchanger and stabilizer (1) Remove the grille. (2) Remove the tabs (2 places) in the center of stabilizer and remove the drain pan (4 fixing screws). (3) Remove the electrical cover . (4) Disconnect the connectors of the horizontal and vertical vane motors. (5) Remove the indoor coil thermistors (main and sub). (6) Remove the drain cover (3 fixing screws). (7) Remove the pipe band. (8) Remove the heat exchanger (6 fixing screws). (9) Remove the stabilizer (2 fixing screws).
Photo 3
Motor cover of horizontal and vertical vane motors
5. Removing the horizontal and vertical vane motors
(1) Remove the grille. (2) Remove the drain pan. (3) Remove the horizontal
vane. (4) Remove the heat exchanger and stabilizer. (5) Remove the cover of
horizontal and vertical vane
motors (2 fixing screws). (6) Remove the vertical vane motor (2 fixing screws)
and
disconnect the connector (Photo 4). (7) Remove the horizontal vane motor (2
fixing screws)
and disconnect the connector (Photo 4).
Heat exchanger
Photo 4
Stabilizer
Drain pump
Drain sensor
Drain cover
Horizontal vane motor Stabilizer
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OPERATING PROCEDURE
6. Removing the drain pump and drain sensor (1) Remove the grille. (2) Remove
the drain pan. (3) Disconnect the connector of the drain pump (Photo 5). (4)
Disconnect the connector of the drain sensor (Photo 5). (5) Remove the drain
hose (Photo 5). (6) Remove the drain pump assembly (2 fixing screws) (Photo
5). (7) Remove the drain pump cover (2 fixing screws) (Photo 5).
PHOTOS/FIGURES
Photo 5
Connector of the drain pump
Connector of the drain sensor
Fixing screw of the drain pump assembly
Fixing screw of the drain pump cover
Drain pump
Drain sensor
Drain hose
7. Removing the fan motor and line flow fan (1) Remove the grille. (2) Remove the drain pan. (3) Remove the drain cover. (4) Remove the pipe band. (5) Remove the electrical cover . (6) Remove the terminal box. (7) Remove the safety string from the clamps and untie (Photo 6). (8) Hook the safety string to the tabs on the side plate of indoor heat exchanger. (9) Remove the indoor heat exchanger (6 fixing screws) and slide it downward. (10) Remove the stabilizer (2 fixing screws). (11) Partially slide the indoor electric control P.C. board out. (12) Disconnect the connector (CN211) of indoor fan motor. (13) Remove the motor band (2 fixing screws) (Figure 6). (14) Remove the indoor fan motor and line flow fan. (No need to remove the indoor heat exchanger to remove these 2 items.)
Photo 6
Fixing screw of the motor band
Line flow fan (Back side of the heat exchanger)
Fan motor Motor band
Safety string
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MITSUBISHI ELECTRIC TRANE HVAC US LLC
HEAD OFFICE: 1340 SATELLITE BOULEVARD, SUWANEE, GA 30024, USA
© Copyright 2022 MITSUBISHI ELECTRIC CORPORATION Issued: Oct. 2023. No.
OBHT922 REVISED EDITION-A
Published in May 2022. No. OBHT922 Made in Japan
Specifications are subject to change without notice.
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