Mitsubishi Electric MS-18NN Series User manual

SERVICE MANUAL
SPLIT-TYPE, AIR CONDITIONERS
CONTENTS
1. TECHNICAL CHANGES ····································2
2. PART NAMES AND FUNCTIONS······················3
3. SPECIFICATION·················································5
4. OUTLINES AND DIMENSIONS ·························7
5. WIRING DIAGRAM ············································8
6. REFRIGERANT SYSTEM DIAGRAM··············10
7. PERFORMANCE CURVES······························13
8. MICROPROCESSOR CONTROL ····················15
9. SERVICE FUNCTIONS ····································23
10. TROUBLESHOOTING······································24
11. DISASSEMBLY INSTRUCTIONS·····················30
12. PARTS LIST······················································34
13. OPTIONAL PARTS···········································38
Wireless type
Models
No. OB188
MS-18NN - (WH) · MU-18NN -
MS-24NN - (WH) · MU-24NN - S1S1
S1S1
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2
TECHNICAL CHANGES
MS-18JN- ➔MS-18NN-
1. Indoor unit model and outdoor unit model have changed.
2. Indoor fan motor has changed. (S4N-24B-EA ➔ RA4N30-AA)
3. Outdoor fan motor has changed. (S6M-50F-CB ➔ RA6V50-OD)
4. Compressor has changed. (NHJ-36NBD ➔ NH-28NCDT)
5. The remote controller has changed.
6. Microprocessor control has changed.
1
S1 S1
MS-24JN- ➔MS-24NN-
1. Indoor unit model and outdoor unit model have changed.
2. Indoor fan motor has changed. (S4N-26B-BA ➔ RA4N30-AA)
3. Outdoor fan motor has changed. (S6N-60F-AB ➔ RA6V60-AB)
4. Compressor has changed. (NHJ-38NBD ➔ NH-38NBDT)
5. The remote controller has changed.
6. Microprocessor control has changed.
S1 S1
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3
PART NAMES AND FUNCTIONS
2
INDOOR UNIT

OUTDOOR UNIT
MU-18NN- ,MU-24NN- S1S1
MS-18NN- ,MS-24NN- S1S1
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4
REMOTE CONTROLLER
MS-18NN- ,MS-24NN- S1S1
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5
SPECIFICATION
3
Rating Conditions : SSA 385/386 - Indoor DB29°C WB19°C,Outdoor DB46°C WB24°C
JIS - Indoor DB27°C WB19°C,Outdoor DB35°C WB24°C
Note ✽SSA 385/386 can be applied only to Saudi Arabia.
Model MS-18NN-
Function Cooling
Power supply Single phase 220V 60Hz
S1
W4,200
kcal/h 3,600
Electrical Current A10.7
data Input W2,300
Capacities
Capacity kW 5.1
Capacities Dehumidification
R/h 2.5
Air flow
m3/h 780
Current A8.9
Input W1,910
Power factor % 98
Starting current A 55
Compressor motor current A8.15
Fan motor current A0.75
Coefficient of performance 2.67
Electrical
data
Model —NH-28NCDT
Output W1,200
Width
mm<in.>
1,015 <40>
Indoor unit Height
mm<in.>
320 <12-9/16>
Depth
mm<in.>
190 <7-1/2>
Width
mm<in.>
850 <33-1/2>
Outdoor unit Height
mm<in.>
605 <23-13/16>
Depth
mm<in.>
290 <11-3/8>
Indoor unit kg<lb> 14<31>
Outdoor unit kg<lb> 55<121>
Air direction — 5
Indoor
Fan speed unit
(Hi) Outdoor
unit
Indoor
Fan speed unit
regulator Outdoor
unit
Refrigerant filling
capacity (R-22)
Compressor
Dimensions
Weight
Special
remarks
kg<lb>
1.65 <3.63>
rpm
rpm
1,180
865
1
4
SSA 385/386*
JIS
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6
Rating Conditions : SSA 385/386
- Indoor DB29°C WB19°C,Outdoor DB46°C WB24°C
JIS - Indoor DB27°C WB19°C,Outdoor DB35°C WB24°C
Note ✽SSA 385/386 can be applied only to Saudi Arabia.
Model MS-24NN-
Function Cooling
Power supply Single phase 220V 60Hz
S1
W5,500
kcal/h 4,700
Electrical Current A16.1
data Input W3,500
Capacities
Capacity kW 6.6
Capacities Dehumidification
R/h 3.5
Air flow
m3/h 840
Current A13.5
Input W2,930
Power factor %99
Starting current A56
Compressor motor current A12.58
Fan motor current A0.92
Coefficient of performance 2.25
Electrical
data
Model —NH-38NBDT
Output W1,700
Width mm<in.> 1,015 <40>
Indoor unit Height mm<in.> 320 <12-9/16>
Depth mm<in.> 190 <7-1/2>
Width mm<in.> 850 <33-1/2>
Outdoor unit Height mm<in.> 605 <23-13/16>
Depth mm<in.> 290 <11-3/8>
Indoor unit kg<lb> 14 <31>
Outdoor unit kg<lb> 61 <135>
Air direction — 5
Indoor
Fan speed unit
(Hi) Outdoor
unit
Indoor
Fan speed unit
regulator Outdoor
unit
Refrigerant filling
capacity (R-22)
Compressor
Dimensions
Weight
Special
remarks
kg<lb>
2.15 <4.73>
rpm
rpm
1,260
930
4
2
SSA 385/386*
JIS
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7
OUTLINES AND DIMENSIONS
4
1015
320
775 190 50
56
160
17.5 Power supply cord
Lead to right 2m
Lead to left 1m
Air out
Air in
190 5
Installation plate
438 352
Wall hole [75
3297
274
284
20
217
648
450
450
150
40 60
Indoor unit
4holes
11✕20
Installation plate
Liquid line [8-0.5m
Gas line [12-0.43m
Installation [50 O.D
[28 I.D
Drain hose [16
Insulation [28
350 20
35
248
Air in
Air out
290 310
345
30 Service panel
605
292
20
50 183
500
850 74
157
100
Drainage
3holes [16.2
161
Gas refrigerant
pipe joint
Refrigerant pipe (flared)
[15.88
Liquid refrigerant
pipe joint
Refrigerant pipe (flared)
[6.35(MS-18)
[9.52(MS-24)
30
o
35
o
INDOOR UNIT
OUTDOOR UNIT
If a front side or both side is vacant, an upper side of a unit has only to be vacant 10cm.
If both sides or back
side is vacant. only
to be free 50cm in
front of a unit.
MS-18NN-
MS-24NN- S1
S1
MU-18NN-
MU-24NN- S1
S1
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8
NOTES : 1.For the outdoor 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
4.”❈”shows the terminals with a lock mechanism, so they cannot be removed when you pull the lead wire.
Be sure to pull the wire by pushing the locking lever (projected part) of the terminal with a finger.
INDOOR UNIT
WIRING DIAGRAM
5
TRANS
NR11
HIC1 IC141
DSAR
BRN
GRN/YLW
LD1
REMOTE
CONTROLLER
GRN/YLW
3
BLU
BLU
BLU
DISPLAY
P.C.BOARD
3
CN
102
3
BLU
WHT
F12 2
1CN201
1
33
4
F11
5
MV
151
CN 111
CN RT11
BRN
YLW
RED
GRY
WHT
BLK
RECEIVER
P.C.BOARD
BLU
112
CN
121
CN
RT12
2
BRN
101
CN
52C CN211
C11
1
2
4
ELECTRONIC CONTROL P.C BOARD
TB
N
LBRN
TO OUTDOOR
UNIT
CONNECTING
MF
POWER SUPPLY
CORD
1[220V
60Hz
❈
❈
❈
❈
❈
TRANS
NR11
HIC1 IC141
1
DSAR
GRN/YLW
WHT WHT
LD1
REMOTE
CONTROLLER
3
3
BLU
BLU
BLU
DISPLAY
P.C.BOARD
CN
102
3
WHT F12 2
1CN201
1
33
4
F11
5
MV
151
CN 111
CN RT11
BRN
YLW
RED
GRY
WHT
BLK
RECEIVER
P.C.BOARD
BLU
112
CN
121
CN
RT12
2
101
CN
52C CN211
C11
1
2
4
ELECTRONIC CONTROL P.C BOARD
TB
GRN/YLW
N
3RED
TO OUTDOOR
UNIT
CONNECTING
MF
POWER SUPPLY
CORD
1[220V
60Hz
SYMBOL NAME SYMBOL NAME SYMBOL NAME
C11 INDOOR FAN MF INDOOR FAN MOTOR TB TERMINAL BLOCK
DSAR SURGE ABSORBER MV VANE MOTOR IC141 HYBRID IC
F11 FUSE(3.15A) 52C COMPRESSOR CONTACTOR NR11 VARISTOR
F12 FUSE(93°C) RT11 ROOM TEMPERATURE THERMISTOR
HIC1 DC/DC CONVERTER RT12 INDOOR COIL THERMISTOR
MS-18NN- S1 MODEL MS-18NN - WIRING DIAGRAM
S1
MS-24NN- S1 MODEL MS-24NN - WIRING DIAGRAM
S1
11Side the sleeve.
22Pull the wire while
pushing the locking lever.
❈
❈
❈❈
❈
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9
NOTES : 1.Use copper conductors only. (For field wiring)
2.”❈”shows the terminals with a lock mechanism.so they cannot
be removed when you pull the lead wire.
Be sure to pull the wire by pushing the locking
lever (projected part) of the terminal with a finger.
3.Symbols below indicate.
/: Terminal block : Connector
OUTDOOR UNIT
TB GRN/YLW
2
N
TO INDOOR
UNIT
CONNECTING
WHT C
MC R
S
RED
BLK
BLK C1
MF
BLK
WHT
ORN
RED
BLK
WHT
ORN
RED
C2
4
3
2
1
6
5
4
3
2
1
GRY
REDCR
5
GRN/YLW
26F1
X1
BLK
GRY
GRY
BLK
YLW
WHT
52C
52C
6
1
43
65
X1 78
b
a52C
RED
3
N
WHT
YLW
52C
1
2
TB
2C
RS
BLK RED
C1
MC
3
RED
ORN
WHT
BLK
YLW
RED
ORN
WHT
BLK
YLW
C2 MF
TO INDOOR
UNIT
CONNECTING
11Side the sleeve.
22Pull the wire while
pushing the locking lever.
❈
❈
❈
❈
❈
SYMBOL NAME SYMBOL NAME SYMBOL NAME
COMPRESSOR OUTDOOR FAN MOTOR THERMAL REED
CAPACITOR (INNER THERMOSTAT) SWITCH
OUTDOOR FAN
CAPACITOR
COMPRESSOR FAN MOTOR SURGE
(INNER THERMOSTAT) RELAY ABSORBER
C1
MF
26F1
C2
TB
52C
MC
X1
CR
TERMINAL BLOCK
CONTACTOR
SYMBOL NAME SYMBOL NAME
COMPRESSOR FAN MOTOR
CAPACITOR (INNER THERMOSTAT)
FAN MOTOR
CAPACITOR
COMPRESSOR
(INNER THERMOSTAT)
C1
MF
C2
TB
MC
TERMINAL BLOCK
MU-18NN- S1 MODEL MU-18NN - WIRING DIAGRAM
S1
MU-24NN- S1 MODEL MU-24NN - WIRING DIAGRAM
S1
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10
Indoor heat
exchanger
RT11
Room
temperature
thermistor Flared
connector
Flared
connector
Refrigerant pipe
(Option)[6.35
(with heat insulator)
Refrigerant pipe
(Option) [15.88
(with heat insulator)
Stop Valve 2.0 700
1.4 650
DISCHARGE
PRESSURE
REGULATOR
STRAINER
Flow of refrigerant
Compressor
ACCUMULATOR
Stop valve
(With service port)
Indoor coil
thermistor
RT12 Outdoor
heat
exchanger
[
[
REFRIGERANT SYSTEM DIAGRAM
6
INDOOR UNIT
INDOOR UNIT
OUTDOOR UNIT
OUTDOOR UNIT
Indoor heat
exchanger
RT11
Room
temperature
thermistor Flared
connector
Flared
connector
Refrigerant pipe
(Option) 9.52
(with heat insulator)
Refrigerant pipe
(Option) 15.88
(with heat insulator)
Stop Valve 2.0 600
1.6 350
DISCHARGE
PRESSURE
REGULATOR
STRAINER
2.0 100
Flow of refrigerant
Compressor
ACCUMULATOR
Stop valve
(With service port)
Indoor coil
thermistor
RT12 Outdoor
heat
exchanger
[
[
[[
[
Umit:mm
Umit:mm
MS-18NN - S1 MU-18NN - S1
MS-24NN - S1 MU-24NN - S1
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11
Model Outdoor unit precharged Refrigerant piping length (one way)
(up to 7m) 7m 10m 15m
MS-18NN - 1650
MS-24NN - 2150
0
45
120
S1
S1
MAX. HEIGHT DIFFERENCE
ADDITIONAL REFRIGERANT CHARGE(R-22 : g)
Additional piping
Model Max. length : m
AGas Liquid Indoor unit Outdoor unit
MS-18NN - 15
[6.35
MS-24NN -
[9.52
15
[15.88
0.43
0
S1
S1
Piping size O.D : mm
Length of connecting pipe : m
MAX. REFRIGERANT PIPING LENGTH
Note : Calculation : Xg=15g/m✕(A-7)m
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12
EVACUATION PROCEDURES
Pipe length :
7m maximum
No gas charge
is needed
Pipe length
exceeding 7m
Charge the prescribed
amount of gas
Tighten the cap to the service port to obtain the initial status
Retighten the cap
Leak test
After refrigerant pipes are connected and evacuated, fully open all stop valves on gas and liquid pipe sides.
Operating without fully opening lowers the performance and causes trouble.
Remove the gage manifold valve quickly from the service port of the stop valve.
,
,
Leave it as is for one or two minutes. Make sure the pointer
gage manifold valve remains in the same position.
Check the vacuum with the gage manifold valve, then close
the gage manifold valve, and stop the vacuum pump.
Run the vacuum pump(Vacuumize for more than 15 minutes.)
and at this time confirm that the pressure gage shows -0.1
Mpa ( -76cm Hg).
Connect the gage manifold valve and the vacuum pump to
the service port of the stop valve on the gas pipe side of the
outdoor unit.
Connect the refrigerant pipes (both the liquid and gas pipes)
between the indoor and the outdoor units.
Remove the service port cap of the stop valve on the side of the outdoor unit gas pipe (The stop valve will not
work in it initial state fresh out of the factory (totally closed with cap on).)
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13
PERFORMANCE CURVES
MS-18NN- MS-24NN-
The standard data contained in these specifications apply only to the operation of the air conditioner under normal conditions.
Since operating conditions vary according to the areas where these units are installed. The following information has been pro-
vided to clarify the operating characteristics of the air conditioner under the conditions indicated by the performance curve.
(1) GUARANTEED VOLTAGE
Rated voltage : ±10% (198 ~ 242V ) 60Hz
(2) AIR FLOW
Air flow should be set at MAX.
(3) MAIN READINGS
(1) Indoor intake air wet-bulb temperature : °CWB
(2) Indoor discharge air wet-bulb temperature : °CWB
(3) Outdoor intake air dry-bulb temperature : °CDB
(4) Total input: W
Indoor air wet-bulb temperature difference on the left side of the chart on next page shows the difference between the
indoor intake air wet-bulb temperature and the indoor discharge air wet-bulb temperature for your reference at service.
How to measure the indoor air wet-bulb temperature difference
1. Attach at least 2 sets of wet-and dry-bulb thermometers to the indoor air intake as shown in the figure, and at least 2 sets
of wet-and dry-bulb thermometers to the indoor air outlet. The thermometers must be attached to the position where air
speed is high.
2. Attach at least 2 sets of dry-bulb thermometers to the outdoor air intake.
Cover the thermometers to prevent direct rays of the sun.
3. Check that the air filter is cleaned.
4. Open windows and doors of room.
5. Press the EMERGENCY ON/OFF button to start the EMERGENCY operation.
6. When system stabilizes after more than 15 minutes, measure temperature and take an average temperature.
7. 10 minutes later, measure temperature again and check that the temperature does not change.
7
INDOOR UNIT OUTDOOR UNIT
}
Cooling
S1 S1
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14
① Both indoor and outdoor unit are under the same temperature/humidity condition.
OUTDOOR LOW PRESSURE AND OUTDOOR UNIT CURRENT
COOL operation
➁ Air flow should be set at MAX.
Outdoor low pressure(kg/cm2)Outdoor unit current(A)
MU-18NN - S1 MU-24NN - S1
MU-24NN - S1 MU-18NN - S1
Ambient temperature(˚C)
Ambient humidity(%) Ambient temperature(˚C)
Ambient humidity(%)
Ambient temperature(˚C)
Ambient humidity(%) Ambient temperature(˚C)
Ambient humidity(%)
Outdoor low pressure(kg/cm2)
Outdoor unit current(A)
Dry-bulb temperature(;)Relative humidity(%)
20 50
25 60
30 70
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15
Once the controls are set, the same operation mode can be
repeated by simply turning the OPERATE/STOP button ON.
Indoor unit receives the signal with a beep tone.
When the system turns off, 3-minute time delay will operate to
protect system from overload and compressor will not restart
for 3 minutes.
1. “I FEEL CONTROL”OPERATION
(1) Press OPERATE/STOP button on the remote con-
troller. OPERATION INDICATOR LAMP of the
indoor unit will turn on with a beep tone.
(2) Press OPERATION SELECT button to set “I FEEL
CONTROL” Then a beep tone is heard.
(3) The operation mode is determined by the initial
room temperature at start-up of the operation.
MICROPROCESSOR CONTROL
8
Operation Indicator
Wireless remote controller
Example
Previous operation
COOL mode of
“I FEEL CONTROL”
or COOL mode.
● Once the mode is fixed, the mode will not change
by room temperature afterwards.
● Under the ON-TIMER operation, the mode is determined
according to the room temperature as the operation
starts.
● When the system is stopped with the
OPERATE/STOP button on the remote controller,
and restarted within 2 hours in “I FEEL CONTROL”
mode, the system operates in previous mode
automatically regardless of the room temperature.
Initial room temperature mode
COOL mode of
I FEEL CONTROL
DRY mode of
"I FEEL CONTROL"
more than 25°C
13°C to 25°C
Example
Previous operation
COOL mode of “I
FEEL CONTROL”
or COOL mode.
● When the system is restarted after 2 hours, the operation
mode is determined by the initial room temperature at
start-up of the operation.
Restart
COOL mode of “I
FEEL CONTROL”
Restart
COOL or DRY mode of
“I FEEL CONTROL” that
determined by initial
room temperature start-
up of the operation.
INDOOR UNIT DISPLAY SECTION
MS-18NN -
MS-24NN - S1
S1
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16
Model Initial room temperature Initial set temperature
26°C or more 24°C
Initial room temperature
minus 2°C
DRY mode of Initial room temperature
"I FELL CONTROL" minus 2°C
COOL mode of
"I FEEL CONTROL"
26°C or less
13°C to 25°C
❈1 After the system restarts by the remote controller, the system operates with the previous set temperature regardless of
the initial set temperature.
The set temperature is calculated by the previous set temperature.
(5) TEMPERATURES buttons
In “I FEEL CONTROL” mode, set temperature is decided by the microprocessor based on the room temperature.
In addition, set temperature is controlled by TOO WARM or TOO COOL buttons when you feel too cool or too warm.
Pressing the TOO WARM or TOO COOL button emits a beep tone.
● Fuzzy control
When the TOO COOL or TOO WARM button is pressed, the microprocessor changes the set temperature, considering
the room temperature, the frequency of pressing TOO COOL or TOO WARM button and the user’s preference to heat or
cold. So this is called “Fuzzy control”, and works only in “I FEEL CONTROL” mode.
In DRY mode of “I FEEL CONTROL”, the set temperature doesn’t change.
▲ TOO
COOL … To raise the set temperature 1~2 degrees(°C)
▼ TOO
WARM … To lower the set temperature 1~2 degrees(°C)
(4) The initial set temperature is decided by the initial room temperature.
❈1
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17
NOTE : Coil frost prevention during COOL mode of “I FEEL CONTROL”
There are two types of controls in coil frost prevention.
① Temperature control
When the indoor coil thermistor RT12 reads -1°C or below, the coil frost prevention mode starts immediately.
However the coil frost prevention will not work for 5 minutes after the compressor starts.
The compressor stops and the indoor fan operates at the set speed for 5 minutes.
After that, if RT12 still reads below -1°C this mode prolonged until the RT12 reads over -1°C .
② Time control
When the three conditions below have been satisfied for 1 hour and 45 minutes, compressor stops for 3 minutes.
a. Compressor has been continuously operating.
b. Indoor fan speed is Lo or Me.
c. Room temperature is below 26°C.
When compressor turns off half way, the accumulated time is cancelled.
When compressor turns on again, time counting starts from the beginning.
When the indoor fan speed becomes Hi or the room temperature exceeds 26°C, time counting stops temporarily.
After, when the above conditions are satisfied again, time counting restarts.
The indoor fan operates at set speed.
● Indoor fan operates at the set speed by FAN CONTROL
Followings are the fan speed in AUTO.
Room temperature minus set temperature : more than 2 ~ 4 degrees (°C)··············Hi
Room temperature minus set temperature : 1 ~ 4 degrees (°C) ·····························Me
Room temperature minus set temperature : less than 1 ~1.5 degrees (°C)·············Lo
—DRY mode of “I FEEL CONTROL”—
The system for dry operation uses the same refrigerant circuit as the cooling circuit.
The compressor and the indoor fan are controlled by the temperature and the microprocessor.
By such controls, indoor flow amounts will be reduced in order to lower humidity without much room temperature
decrease.
The operation of the compressor and indoor fan is as follows.
1. When the room temperature is 23°C or over:
Compressor operates by temperature control and time control.
① Set temperature is controlled to fall 2°C as initial set temperature.
② When the thermostat is ON, the compressor repeats 8 minutes ON and 3 minutes OFF.
When the thermostat is OFF, the compressor repeats 4 minutes OFF and 1 minute ON.
Indoor fan and outdoor fan operate in the same cycle as the compressor.
2. When the room temperature is under 23°C.
When the thermostat is ON, the compressor repeats 2 minutes ON and 3 minutes OFF.
When the thermostat is OFF, the compressor repeats 4 minutes OFF and 1 minute ON.
1 deg. 1.5 deg.
2 deg. 4 deg.
— COOL mode of “I FEEL CONTROL” —
Compressor and
outdoor fan motor OFF
ON
Run continuously in cooling mode
Indoor fan motor ON
ON
OFF
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18
Operation time chart
Example
NOTE ● Coil frost prevention during DRY mode of “I FEEL CONTROL”
The operation is same as coil frost prevention during COOL mode of “I FEEL CONTROL” excepting the
indoor fan is OFF.
● Coil frost becomes the fan speed Lo during the indoor fan is OFF.
(Because the coil frost prevention is priority.)
2. COOL OPERATION
(1) Press OPERATE/STOP button.
OPERATION INDICATOR of the indoor unit
turns on with a beep tone.
(2) Select COOL mode.
(3) Set the TEMPERATURES button.
(TOO WARM or TOO COOL button)
The setting range is 16 ~ 31°C
✻ Indoor fan continues to operate regardless
of thermostat’s OFF-ON
✻ Coil frost prevention is same as COOL
mode of “I FEEL CONTROL”
3. DRY OPERATION
(1) Press OPERATE/STOP button.
OPERATION INDICATOR of the indoor unit
turns on with a beep tone.
(2) Select DRY mode.
(3) The microprocessor reads the room temper-
ature and determines the set temperature.
Set temperature is as shown in the right
chart.
Thermostat (SET TEMP.)is not work.
The other operations are same as DRY
mode of “I FEEL CONTROL”.
(4) DRY operation will not work when the room
temperature is 13°C or below.
(5) When DRY operation works, the fan speed is
lower than cool operation.
Thermostat
Indoor fan
Outdoor fan
compressor
1st ON
8 min. 1 min.
3 min.
ON
OFF
OFF
OFF
OFF
OFF
ON
ON
ON
ON
ON
ON
OFF
OFF
OFF 4 min.
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6. AUTO VANE OPERATION
(1) Vane motor drive
MS series is equipped with a stepping motor for the vane. The rotating direction, speed, and angle of the motor are con-
trolled by plus signals (approx. 12V) transmitted from indoor microprocessor.
(2) The auto vane angle changes as follows by pressing the VANE CONTROL button.
5. FAN MOTOR CONTROL
(1) Rotational frequency feedback control
The indoor fan motor is equipped with a rotational frequency sensor, and outputs signal to the microprocessor to feedback
the rotational frequency. Comparing the current rotational frequency with the target rotational frequency (Hi,Me,Lo) the
microprocessor controls IC141 and adjusts fan motor electric current to make the current rotational frequency close to the
target rotational frequency. With this control, when the fan speed is switched, the rotational frequency changes more
smoothly than before.
(2) Fan motor lock-up protection
When the rotational frequency feedback signal is not output for 12 seconds, (or when the microprocessor cannot detect the
signal for 12 seconds) the fan motor is regarded locked-up. Then the electric current to the fan motor is shut off. 3 minutes
later, the electric current is applied to the fan motor again. During the fan motor lock-up, the operation indicator flashes to
show the fan motor abnormality. (See page 25.)
4.FAN OPERATION
(1)Press OPERATE/STOP button.
(2)Select FAN mode.
(3)Select the desired fan speed.When AUTO,it becomes LO.(Only DRY operation)
Only indoor fan operates.Outdoor unit does not operate.
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(3) Positioning
The vane is once pressed to the vane stopper below to confirm the standard position and then set to the desired angle.
The positioning is decided as follows.
(a) When the operate button is pushed. (POWER ON)
(b) When th stop button is pushed. (POWER OFF)
(c) When the vane control change AUTO to MANUAL.
(d) When the SWING is finished.
(e) When the test run starts.
(f ) When the power supply is ON.
(4) VANE AUTO mode
In VANE AUTO mode, the microprocessor automatically determines the vane angle and operation to make the optimum
room-temperature distribution.
(5) Dew prevention
During COOL or DRY operation with the vane angle at Downward when the compressor cumulative operation the exceeds
1 hour, the vane angle automatically changes to Horizontal for dew prevention.
(6) SWING MODE
By pressing the SWING button, vane swings vertically. The remote controller displays SWING mode is cancelled when the
SWING button is pressed again or the operation stops or changes to other mode or VANE button is pressed.
① In COOL and DRY operation
➁ In FAN operation
Vane angle is fixed to Horizontal.
Vane angle is fixed to Downward.
7. SLEEP MODE
• When the SLEEP button is pressed, the indoor fan speed drops and the air flow sound from the indoor unit is decrecsed.
• The indications of the remote controller are “ ” and “ AUTO ”.
• When the FAN SPEED CONTROL button is pressed during the SLEEP mode operation, the SLEEP made is released.
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