Mitsubishi Electric Mr.SLIM MS24WN User manual

SERVICE MANUAL
CONTENTS
1. FEATURES·························································3
2. PART NAMES AND FUNCTIONS······················4
3. SPECIFICATION·················································6
4. DATA···································································8
5. OUTLINES AND DIMENSIONS ·······················12
6. WIRING DIAGRAM ··········································14
7. REFRIGERANT SYSTEM DIAGRAM··············15
8. MICROPROCESSOR CONTROL ····················16
9. SERVICE FUNCTIONS ····································25
10. TROUBLESHOOTING······································27
11. DISASSEMBLY INSTRUCTIONS·····················40
12. PARTS LIST······················································44
13. OPTIONAL PARTS ······················BACK COVER
Wireless type
Models
MS24WN (W) · MU24WN
The Slim Line.
From Mitsubishi Electric.
L
I
S
T
E
D
CUS
Remote
controller
TM
SPLIT-TYPE, AIR CONDITIONERS
INDOOR UNIT
Indication of model name
MS24WN
OUTDOOR UNIT
Indication of model name
MU24WN
Revision:
●PARTS LIST have been partially modified.
●Please void OB311.
No. OB311
REVISED EDITION-A
OB311--1.qxp 04.1.13 9:53 AM Page 1

Revision:
• Parts No. has been changed due to the color change of outdoor unit parts. WHITE➔NEW WHITE (Brighter)
• Capillary tube has been added to parts list.
CAPILLARY TUBE (TAPER PIPE)
[0.14X[0.09X1-31/32 E02 784 936
Part number
Part name
Model
MU24WN
Page
47
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3
FEATURES
1
“I FEEL CONTROL” IN OUR LCD WIRELESS REMOTE CONTROLLER WITH ON/OFF PROGRAM TIMER
Mitsubishi Electric’s new wireless remote controller incorporates a number of advanced features that provide even greater con-
trol and ease-to-use. It has a liquid crystal display which indicates such information as mode, fan speed and temperature
selected as well as the programmed ON/OFF timer. It is also equipped with “I Feel Control”, a unique Mitsubishi Electric fea-
ture that allows the user to adjust the temperature to exactly the level he or she wants simply by tapping the button that
describes present conditions : “Too Cool” or “Too Warm”. The optimum temperature set this way is then memorized for immedi-
ate recall whenever the air conditioner is used again.
Select desired air flow direction.
REMOTE-CONTROL OPERATION MODE
Using the remote controller, you can select from five airflow set-
tings to match room layout and the location of people. Also, you
can set the vane to swing automatically.
SWING
AUTO-RESTART FUNCTION
The auto restart function restarts the equipment automatically
when power is restored following an outage. Operation resumes in
the mode in which the equipment was running just before the out-
age.
HIGH PERFORMANCE ROTARY COMPRESSOR
The advanced design of Mitsubishi Electric’s powerful and energy
efficient rotary compressor results in lower operating costs and
longer service life.
LCD wireless
remote controller
MS24WN
Model 22,800 Btu/h
Cooling capacity
10.5
SEER
SWING
MS24WN
MU24WN
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4
PART NAMES AND FUNCTIONS
2
INDOOR UNIT
MS24WN
Installation plate
Installation plate fixing screw 4 x 25 mm(0.16 x 0.98 in.)
Remote controller holder
Fixing screw for 33.5 x 16 mm(0.14 x 0.63 in.) (Black)
Battery (AAA) for remote controller
Wireless remote controller
Felt tape (Used for left or left-rear piping)
1
7
1
2
2
1
1
1
2
3
4
5
6
7
MS24WN
ACCESSORIES
Grille
Air inlet
Remote control
receiving section
Horizontal vane
Remote controller
Deodorizing filter (option)
(Gray sponge type)
Air cleaning filter (option)
(White bellows type)
Air filter
Vertical vane
Operation section
(When the grille is opened)
Display section
Operation indicator lamp
Receiving section
Emergency operation switch
Front panel
Operation Indicator
OUTDOOR UNIT
MU24WN
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5
REMOTE CONTROLLER
MS24WN
ON/OFF
TOO
COOL
PM
AM
TOO
WARM
ON/OFF
FAN
TOO
WARM TOO COOL
VANE
MODE
STOP
START
HR.
MIN.
WIDE VANE
LONG
I FEEL COOL
DRY
PM
CLOCK
AM
RESET CLOCK
FAN
Open the front lid.
Signal transmitting section
Operation display section
OPERATE/ STOP
(ON/ OFF)button
TEMPERATURE buttons
OPERATION SELECT button
FAN SPEED CONTROL button
OFF-TIMER button
HR. button
MIN. button
(TIME SET button)
ON-TIMER button
RESET button
VANE button
(Horizontal vane button)
CLOCK SET button
LONG button
WIDE VANE button
(Vertical vane button)
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6
3
Notes : Test conditions are based on ARI 210/240
❈1 : Rating conditions (cooling) — Indoor : 80˚FDB, 67˚FWB, Outdoor : 95˚FDB, (75˚FWB)
❈2 : Rating conditions (cooling) — Indoor : 80˚FDB, 67˚FWB, Outdoor : 82˚FDB, 65˚FWB
Operating Range
Item Model
Cooling capacity
Power consumption
EER [SEER]
INDOOR UNIT MODEL
External finish
Power supply
Max. fuse size (time delay)/ Disconnect switch
Min. ampacity
Fan motor
Airflow Low—Med.—High
Moisture removal
Sound level Low-Med.-High
Cond. drain connection O.D.
Dimensions
Weight
OUTDOOR UNIT MODEL
External finish
Power supply
Max. fuse size (time delay)
Min. ampacity
Fan motor
Compressor
Refrigerant control
Sound level
Dimensions
Weight
REMOTE CONTROLLER
Control voltage (by built-in transformer)
REFRIGERANT PIPING
Pipe size
(Min. wall thickness)
Connection method
Between the indoor
& outdoor units
Refrigerant charge (R22)
Refrigerant oil (Model)
FAN Dry
COOL Dry(Wet)
W
D
H
Model
Winding resistance (at 68˚F) Ω
W
D
H
Liquid
Gas
Indoor
Outdoor
Height difference
Piping length
Btu/h
W
A
A
F.L.A
CFM
CFM
pt./h
dB(A)
in.
in.
in.
in.
lb.
A
A
F.L.A
R.L.A
L.R.A
dB(A)
in.
in.
in.
lb.
in.
in.
ft.
ft.
oz.
22,800
2,170
10.5 (10.5)
MS24WN
White
115V 60Hz 1[
15
1.1
0.82
431-491-565
402(346)-484(417)-565(487)
7.6
39-43-47
5/8
43-5/16
8-15/16
12-13/16
40
MU24WN
Munsell 5Y7/1
208/230V 60Hz 1[3 wires
25
22
0.87
PH33NPBT
C-R 0.84 C-S 2.09
16
58
Linear expansion valve
55
34-1/4
11-5/8
33-1/2
152
Wireless type
12V DC
Not supplied (optional parts)
3/8 (0.0285)
5/8 (0.0315)
Flared
Flared
Max. 25
Max. 50
4 Ib. 5 oz.
27.9 (MS32N1)
MS24WN
❈1
❈1
❈1❈2
Cooling Maximum
Minimum
Indoor intake air temperature
95˚FDB, 71˚FWB
67˚FDB, 57˚FWB
Outdoor intake air temperature
115˚FDB
67˚FDB
SPECIFICATION
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7
wHeight difference
should be within
25ft. regardless of
which unit, indoor
or outdoor
position is high.
wMax. Height
difference 25ft. Additional Piping
Max. length
A
Indoor
unit
Outdoor unit
MAX. HEIGHT DIFFERENCE
Outside
diameter Minimum
Wall
thickness Outside
diameter Minimum
Wall
thickness
MS24WN MU24WN
Additional piping
Max. length : ft.
A
50
GasPiping size : in. Length of connecting pipe : in. Liquid Indoor unit Outdoor unit
Model
Gas :
Liquid : 0 0
Gas :
Liquid :16-15/16
19-11/16
[ 5/8 [ 3/8
0.0315 0.0285
MAX. REFRIGERANT PIPING LENGTH & MAX. HEIGHT DIFFERENCE
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8
DATA
4
4-1. PERFORMANCE DATA
1) COOLING CAPACITY
MS24WN MU24WN
Model Refrigerant piping length (one way)
1.0
25ft. (std.)
0.954
40ft.
0.923
50ft.
MS24WN
2) COOLING CAPACITY CORRECTIONS
Model
Indoor air Outdoor intake air DB temperature(˚F)
71
67
63
TC
27.9
26.4
24.9
SHC
13.9
16.7
19.0
TPC
1.93
1.82
1.74
TC
26.1
24.6
23.0
SHC
13.0
15.5
17.6
TPC
2.12
2.01
1.92
TC
24.5
22.8
21.4
SHC
12.2
14.4
16.4
TPC
2.28
2.17
2.07
TC
22.8
21.2
19.5
SHC
11.3
13.4
14.9
TPC
2.40
2.30
2.21
TC
21.0
19.5
17.8
SHC
10.4
12.3
13.6
TPC
2.50
2.41
2.30
IWB
(˚F)75 85 95 105 115
MS24WN
(208V/ 230V)
Notes 1.IWB : Intake air wet-bulb temperature.
TC : Total Capacity (x103 Btu/h), SHC : Sensible Heat Capacity (x103 Btu/h)
TPC : Total Power Consumption (kW)
2.SHC is based on 80˚F of indoor intake air DB temperature.
4-2. PERFORMANCE CURVE
MS24WN
MU24WN
16
18
20
22
24
26
28
30
65 70 75 80 85 90 95 100 105 110 115
1.4
1.6
1.8
2.0
2.2
2.4
2.6
71
67
63
71
67
63
Total power consumption (kW) Total capacity ( ✕10 Btu/h)
Outdoor intake air DB temperature (°F)
Indoor intake air WB temperature (°F)
Indoor intake air WB temperature (°F)
Cooling
SHF at rating condition = 0.63
= 487CFM
= 0.16
Airflow
Bypass Factor
208V/230V
208V/230V
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9
4-3. Condensing pressure
Data is based on the condition of indoor humidity 50%.
Air flow should be set at High.
MU24WN
70 75 80 85 90 95 100 104(°F)
40
50
60
70
80
90
100
70 75 80 85 90 95 100 104(°F)
160
180
200
220
240
260
280
300
86
80
75
70
Condensing pressure
Outdoor ambient temperature
(PSIG)
86
80
75
70
Indoor DB temperature
Indoor DB temperature
(PSIG)
68
Suction pressure
Outdoor ambient temperature
68
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10
✻ Control voltage
Power supply voltage to
serial signal circuit is 12V DC.
Voltage between 11+ and 33--
on in-out terminal block will be
12V DC peak.
•Both wirings can be applied.
MS24WN INDOOR UNIT INDOOR UNIT
115V 60Hz 1[,
2wires
OUTDOOR UNIT
208/230V
60Hz 1[, 3 wires
SIGNAL WIRE
2 wires 12V DC OUTDOOR UNIT
208/230V
60Hz 1[, 3 wires
115V 60Hz 1[,
2 wires
Disconnect switch
SIGNAL WIRE
2 wires 12V DC
115V
4-4. STANDARD OPERATION DATA
MS24WN
Cooling
22,800
0.63
2.17
MS24WN
115V 60Hz 1[
0.071
0.62
MU24WN
208/230V 60Hz 1[
2.099
9.36/ 8.30
0.67/0.71
250
71
174
115
48
158
25
4 Ib. 5 oz.
80
67
51
50
1,280
487(Wet)
95
—
750/820
1,589/1,765
Capacity
SHF
Input
INDOOR UNIT MODEL
Power supply
Input
Fan motor current
OUTDOOR UNIT MODEL
Power supply
Input
Comp. current
Fan motor current
Condensing pressure
Suction pressure
Discharge temperature
Condensing temperature
Suction temperature
Comp. shell bottom temp
Ref. pipe length
Refrigerant charge (R22)
Intake air temperature
Discharge air temperature
Fan speed (High)
Airflow (High)
Intake air temperature
Fan speed
Airflow
Unit
Btu / h
—
kW
kW
A
kW
A
A
PSIG
PSIG
˚F
˚F
˚F
˚F
ft.
—
˚F
˚F
˚F
˚F
rpm
CFM
˚F
˚F
rpm
CFM
DB
WB
DB
WB
DB
WB
Item
Model
Total
Electrical
circuit
Refrigerant
circuit
Indoor
unit
Outdoor
unit
POWER SUPPLY
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11
4-6. OUTLET AIR SPEED AND COVERAGE RANGE
Model
MS24WN
Mode
FAN
COOL 565
487
Air flow
(CFM) Air speed (ft./sec.) Coverage range (ft.)
Function
Dry
Wet 34.2
29.4
20.1
17.2
4-7. ADDITIONAL REFRIGERANT CHARGE (R22(oz.))
MS24WN MU24WN
Outdoor unit
precharged
(up to 25ft.)
4 lb. 5 oz.
25ft.
0
30ft.
0.81
35ft.
1.62
Refrigerant piping length (one way)
40ft.
2.43
45ft.
3.24
50ft.
4.05
Model
CALCULATION : Xoz. = 0.81/ 5oz./ft. x (Additional Piping Length-25) ft.
(2) OPERATION
Function
Cooling
Standard temperature
Maximum temperature
Minimum temperature
Maximum humidity
DB (˚F)
80
95
67
WB (˚F)
67
71
57
Indoor
78%
DB (˚F)
95
115
67
WB (˚F)
—
—
—
Outdoor
—
Condition
Intake air
temperature
●The air coverage range is the figure up to the position where the air speed is 1 ft./sec., when air is blown out horizontally from
the unit properly at the High speed position.
The coverage range should be used only as a general guideline since it varies according to the size of the room and furniture
arranged in the room.
4-5. OPERATING RANGE
(1) POWER SUPPLY
Indoor unit
Outdoor unit
Rating
115V 60Hz 1[
208/230V 60Hz 1[
Guaranteed Voltage
MS24WN
MU24WN
Model
Min. 103V Max. 127V 115V
Min. 198V Max. 253V
208V 230V
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12
OUTLINES AND DIMENSIONS
5
MS24WN
INDOOR UNIT
Unit: inch
6-3/8
3/4
2-5/16
1-7/8
5/16
12-3/8
10-1/161-7/8
1/8
3-7/8
3-7/8
6-13/16
6-13/16
16-5/16 16-5/16
3/168-7/8
8-15/16
9-15/16
31-1/8
2-3/16
42-1/16
43-5/16
12-13/16
Air out
Air in
Insulation [1-1/8
Drain hose [5/8
(Connected part O.D)
{
Liquid line [3/8 19-11/16
Gas line [3/4 16-15/16
Insulation [1-15/16 O.D
[1-1/4 I.D
Installation plate
Wall hole [2-15/16
Wireless remote controller
Installation plate Indoor unit
OB311--1.qxp 04.1.13 9:53 AM Page 12

13
MU24WN
OUTDOOR UNIT
413/32
39-3/8
For 10 units or less
7-7/8
Outdoor Unit-Necessary surrounding clearance
(Concentrated installation) The upper side must be open.
Outdoor Unit-Necessary surrounding clearance
7-7/8
13/32
13/32
13/32
Note:Allow adequate
upper clearance
5-29/32
19-11/16
19-11/16
Service space
Front opening
R13/16
R13/16
1 max.
Standard bolt length
2-9/16
Front right piping holes-
detail figures
3-1/8
11/16
1/2
R1/4
15/16
1-5/16
Side air intake
9/32 15/16 11-5/8
Outlet guide
installation hole
11-7/8
Air intake
Air intake
Air outlet
34-1/4
7-9/32 7-9/32
19-11/16
13
14-1/4 11/16
9/16
1-9/16 1-1/16
Terminal block for indoor and outdoor unit connection
Terminal block for power line
Handle for moving
7-1/18 20-5/8
17-3/8
17-17/32
17-23/32
18-7/18
21-3/4
33-1/2
1-9/16 2-3/8 20-5/8
Service panel
Refrigerant-pipe flared
connection [5/8
Refrigerant-pipe flared
connection [3/8
Knock out hole
for front piping
(refrigerant,drainage
and wiring)
1-5/8
1-3/4
4-1/8
1-5/16
Bottom
piping hole
2-U-shaped
notched
holes
Drain hole [1-5/16
Drain hole [1-5/16
2-1/2o7/8 Oval holes
(standard bolt M10)
Handle for moving
A
Handle
for moving
5-7/16
3-3/4 Rear piping hole
Rear fresh
air intake
A
Knock out hole
for right piping
(refrigerant,drainage
and wiring)
4-3/4
1-3/4
2-1/16
Knock out holes for
power line 2-[1-1/16
2-3/8
NOTE: Do not wire12V DC and
115V AC in same conduit hole.
Conduit hole
Unit: inch
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14
6
MS24WN
MU24WN
MODEL WIRING DIAGRAM
MODEL WIRING DIAGRAM
INDOOR UNIT
OUTDOOR UNIT
OUTDOOR ELECTRONIC CONTROL P.C. BOARD
FROM INDOOR UNIT
CONNECTING WIRES
12V DC
TO INDOOR UNIT
CONNECTING
WIRES
115V
1 phase 60Hz
BLK
RED
FROM INDOOR UNIT
CONNECTING WIRE
RED
RED
GROUND
GRN/YLW
RED
BLU
VLT
BLU
7
POWER
SUPPLY
208/230V
1 phase 60Hz
BLK
152C 2
RED C2
ORN
CN730
A2 A1
BLU 52C
WHT
C1 RED
BLK
S
C
R
NR61
5
3
BLU
T61
X52
ORN
SR61
COM NO
F61
X52 TAB52
1
CN711
CN662 CN724
6
MF
RT62 RT63
123
21
BLK
WHTWHT
ORN
RED
3456
LEV
TB2
3
TB1
L1
N
L2
1
N
L1
DSAR
-
+
MC
NOTE: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
NOTE:1. About the indoor side electric wiring, refer to the indoor unit electric wiring diagram for servicing.
2. Use copper conductors only.(For field wiring)
3. Symbols below indicate;
: Terminal block, : Connector
WIRING DIAGRAM
SYMBOL
TB2
T61
X52
52C
SYMBOL
MF
NR61
RT62
RT63
SR61
TB1
SYMBOL
C1
C2
DSAR
F61
LEV
MC
NAME NAME NAME
COMPRESSOR CAPACITOR
OUTDOOR FAN CAPACITOR
SURGE ABSORBER
FUSE(3.15A)
EXPANSION VALVE COIL
COMPRESSOR(INNER PROTECTOR)
OUTDOOR FAN MOTOR(INNER PROTECTOR)
VARISTOR
DISCHARGE TEMPERATURE THERMISTOR
AMBIENT TEMPERATURE THERMISTOR
SOLID STATE RELAY
TERMINAL BLOCK
TERMINAL BLOCK
TRANSFORMER
COMPRESSOR AUXILIARY RELAY
COMPRESSOR CONTACTOR
SG79J606H02
TAB12
POWER
FROM OUTDOOR
UNIT
CONNECTING
WIRES
TO OUTDOOR
UNIT
CONNECTING
WIRE
SUPPLY
115V
1 phase
60Hz
CN201 RT13
121
CN
CN211
CN112
TO OUTDOOR
UNIT
CONNECTING
WIRES
12V DC
3
F11
VLT
1-
3+
15
3
REMOTE
CONTROLLER
MV2 MV2 MV1
BLK
GRY
TRANS
HIC1
C11
N
L1
BLK
ORN
WHT
BRN
YLW
RED
ELECTRONIC CONTROL P.C. BOARD
NR11
RED
MF
RT12
CN
151 CN
101
3
DISPLAY
P.C.BOARD RECEIVER P.C.BOARD
CN
102
SR141 1
3
4
4
3
2
1
RT11
111
CN
1
2
3
4
TB
w
()
wA disconnect may be required by local code.
SYMBOL
RT12
RT13
SR141
TB
SYMBOL
MV1
MV2
NR11
RT11
SYMBOL
C11
F11
HIC1
MF
NAME NAME NAME
INDOOR FAN CAPACITOR
FUSE(3.15A)
DC/DC CONVERTER
INDOOR FAN MOTOR (INNER PROTECTOR)
VANE MOTOR(HORIZONTAL)
VANE MOTOR(VERTICAL)
VARISTOR
ROOM TEMPERATURE THERMISTOR
INDOOR COIL THERMISTOR(MAIN)
INDOOR COIL THERMISTOR(SUB)
SOLID STATE RELAY
TERMINAL BLOCK
SG79J618H02
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15
REFRIGERANT SYSTEM DIAGRAM
7
Indoor
heat
exchanger
Outdoor
heat
exchanger
Flared connection
Room temperature
thermistor
RT11
Indoor coil
thermistor
RT13(sub)
Discharge
temperature
thermistor
RT62
Flared connection
Stop valve
Stop valve
(with service port)
Capillary tube
O.D.0.14✕I.D.0.09✕1-31/32 Refrigerant flow in cooling
Compressor
Refrigerant pipe [5/8
(with heat insulator)
Refrigerant pipe [3/8
(with heat insulator)
Indoor coil
thermistor
RT12(main)
LEV
Strainer
Strainer
Accumulator Ambient
temperature
thermistor
RT63
Strainer
#50
Capillary tube
O.D.0.16✕I.D.0.09✕7-7/8
(Upper path) Capillary tube
O.D.0.16✕I.D.0.09✕3-15/16
(Lower path)
SERVICE
PORT
SERVICE
PORT
FUSIBLE
PLUG
#100
#100
MS24WN
INDOOR UNIT OUTDOOR UNIT
MU24WN
Unit: inch
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16
When the system is restarted after 2 hours and more,
the operation mode is determined by the room temper-
ature at start-up of the operation.
8MICROPROCESSOR CONTROL
Once the operation mode is set, the same operation mode
can be repeated by simply turning the
OPERATE/STOP(ON/OFF) 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.
8-1. “I FEEL CONTROL” ( ) OPERATION
(1) Press OPERATE/STOP(ON/OFF) button on the remote
controller. OPERATION INDICATOR lamp of the indoor
unit turns on with a beep tone.
(2) Select “I FEEL CONTROL”( ) mode with the OPERA-
TION SELECT button.
(3) The operation mode is determined by the room temper-
ature at start-up of the operation.
lighted
not lighted
Approx. 4-F
or more
Difference
between set
temperature
and room
temperature
Approx. 4-F
or less
This shows that the
air conditioner is
operating to reach
the target temperature.
Please wait until the
target temperature is
obtained.
This shows that the
room temperature is
approaching the
target temperature.
Operation stateIndication
Operation Indicator
Operation Indicator lamp
The operation indicator at the right side of the indoor
unit indicates the operation state.
INDOOR UNIT DISPLAY SECTION
• The following indication applies regardless of shape
of the indicator.
MS24WN MU24WN
Initial room temperature
more than 55-F,
less than 77-F
COOL mode of
“I FEEL CONTROL“
DRY mode of
“I FEEL CONTROL”
WIRELESS REMOTE CONTROLLER
ON/OFF
FAN
TOO
WARM TOO COOL
VANE
MODE
STOP
START
HR.
MIN.
WIDE VANE
LONG
I FEEL COOL
DRY
PM
CLOCK
AM
RESET CLOCK
OPERATION SELECT button
FAN SPEED CONTROL button
OFF-TIMER button
HR. button
MIN. button
(TIME SET button)
ON-TIMER button
RESET button
VANE button
(Horizontal vane button)
CLOCK SET button
LONG button
WIDE VANE button
(Vertical vane button)
ON/OFF
TOO
COOL
PM
AM
TOO
WARM
FAN
Signal transmitting section
Operation display section
OPERATE/ STOP
(ON/ OFF)button
TEMPERATURE buttons
77-F or more
mode
● Once the mode is fixed, the mode does not change
by room temperature afterwards.
● Under the ON-TIMER ( ) operation, the mode
is determined according to the room temperature at
the set time the operation starts.
● When the system is stopped 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.
Example
Previous operation
COOL mode of
“I FEEL CONTROL” or
COOL mode
Restart
COOL mode of
“I FEEL CONTROL”
Operation timer chart
Example
Previous operation
COOL mode of
“I FEEL CONTROL”
or COOL mode
Operation timer chart Restart
COOL or DRY mode of
“I FEEL CONTROL” that
determined by room
temperature at start-up
of the operation.
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17
Mode
COOL mode of
"I FEEL CONTROL"
DRY mode of
"I FEEL CONTROL"
Initial room temperature Initial set temperature
79-F or more
77-F to 79-F
more than 55-F, less than 77-F
75-F
Initial room temperature
minus 4-F
Initial room temperature
minus 4-F
❈1
w1 When the system is restarted with the remote controller, the system operates with the previous set temperature regard-
less of the room temperature at restart.
The set temperature is calculated by the previous set temperature.
(5) TEMPERATURE buttons
In “I FEEL CONTROL” ( ) mode, set temperature is decided by the microprocessor based on the room temperature.
In addition, set temperature can be controlled by TOO WARM or TOO COOL buttons when you feel too cool or too warm.
Each time the TOO WARM or TOO COOL button is pressed the indoor unit receives the signal and 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
cool. 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.
… To raise the set temperature 2~4 degrees(°F)
… To lower the set temperature 2~4 degrees(°F)
(4) The initial set temperature is decided by the initial room temperature.
TOO
COOL
TOO
WARM
2Time control
When the three conditions as follows 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 Low or Med.
c. Room temperature is below 79°F.
When compressor stops, the accumulated time is cancelled and when compressor restarts, time counting starts
from the beginning.
Time counting also stops temporarily when the indoor fan speed becomes High or the room temperature exceeds
79°F. However, when two of the above conditions (b.and c.) are satisfied again. Time accumulation is resumed.
1. Indoor fan speed control
Indoor fan operates at the set speed by FAN SPEED CONTROL button.
In AUTO the fan speed is as follows. Initial temperature difference
Room temperature minus set temperature : 3 degrees or more········································High
Room temperature minus set temperature : Between 2 and 3 degrees····························Med.
Room temperature minus set temperature : less than 2 degree·······································Low
2. Coil frost prevention
1Temperature control
When the indoor coil thermistor RT12 or RT13 reads 30°F or below, the coil frost prevention mode starts immediately.
However the coil frost prevention doesn’t work for 5 minutes since the compressor has started.
The indoor fan operates at the set speed and the compressor stops for 5 minutes.
After that, if RT12 or RT13 still reads below 30°F this mode prolonged until the RT12 and RT13 reads over 30°F.
2 deg. 3 deg. 4 deg.
8-1-1. COOL mode of “I FEEL CONTROL”
Fan speed
Difference between room
temperature and set tem-
perature during operation
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Operation time chart
Example
Thermostat
Indoor fan
Outdoor fan
Compressor
ON
8 min. 1 min.
3 min.
ON
OFF
OFF
OFF
OFF
OFF
ON
ON
ON
ON
ON
ON
OFF
OFF
OFF
3. Coil frost prevention
The operation is as same as coil frost prevention during COOL mode of “I FEEL CONTROL”.
Indoor fan operates at the set speed and the compressor stops for 5minutes, because protection (Coil frost prevention) has
the priority. However when coil frost prevention works while the compressor is not operating, it’s speed becomes Low.
4 min.
Compressor
Outdoor fan OFF
ON
(continuously at set speed)
Indoor fan ON
ON
OFF
Operation chart
Example
3. Discharge temperature protection
The compressor is controlled by the temperature of discharge temperature thermistor RT62 for excess rise protection of
compressor discharge pressure.
• Compressor
When the temperature of discharge temperature thermistor RT62 goes to 248°F or more, the compressor is turned OFF.
After 3 minutes since the compressor has been turned OFF, if the temperature of discharge temperature thermistor RT62
becomes 212°F or less, the compressor is turned ON.
8-1-2. 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 room temperature.
By such controls, indoor flow amounts will be reduced in order to lower humidity without much room temperature
decrease.
1. Indoor fan speed control
Indoor fan operates at the set speed by FAN SPEED CONTROL button.
However, in AUTO fan operation, fan speed becomes Low.
2. The operation of the compressor and indoor / outdoor fan
Compressor operates by room temperature control and time control.
Set temperature is controlled to fall 4°F from initial room temperature.
Indoor fan and outdoor fan operate in the same cycle as the compressor.
• When the room temperature is 73°F or over:
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.
• When the room temperature is under 73°F.
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.
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8-3. DRY ( ) OPERATION
(1) Press OPERATE/STOP(ON/OFF) button.
OPERATION INDICATOR lamp of the indoor unit
turns on with a beep tone.
(2) Select DRY mode with the OPERATION SELECT
button.
(3) The microprocessor reads the room temperature
and determines the set temperature. Set tempera-
ture is as shown on the right chart.
Thermostat (SET TEMP.) does not work.
The other operations are same as DRY mode of “I
FEEL CONTROL”.
(4) DRY operation will not function when the room tem-
perature is 55°F or below.
8-4. FAN( d )OPERATION
(1) Press OPERATE/STOP(ON/OFF) button.
OPERATION INDICATOR lamp of the indoor unit
turns ON with a beep tone.
(2) Select FAN mode with the OPERATION SELECT
button.
Only indoor fan operates. Outdoor unit does not
operate.
86
77
68
59
5050 59 68 77 86 95
95
-F
-F
Set temperature
Initial room temperature
Set temperature and initial temperature in DRY mode
8-2. COOL ( ) OPERATION
(1) Press OPERATE/STOP(ON/OFF) button.
OPERATION INDICATOR lamp of the indoor unit turns on with a beep tone.
(2) Select COOL mode with the OPERATION SELECT button.
(3) Press TEMPERATURE buttons.
(TOO WARM or TOO COOL button) to select the desired temperature.
The setting range is 59 ~ 89°F.
wIndoor fan continues to operate regardless of thermostat’s OFF-ON at set speed.
wCoil frost prevention is as same as COOL mode of “I FEEL CONTROL”.
High
Med. Low
High
8-5. 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
(High,Med.,Low), the microprocessor controls, SR141 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 smoothly.
(2) Fan motor lock-up protection
When the rotational frequency feedback signal has 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 lamp flashes on and off to show the fan motor abnormality. (Refer to page 29.)
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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.
Confirming of standard position is performed in case of follows.
(a) When the OPERATE/STOP(ON/OFF) button is pressed(POWER ON/OFF).
(b) When the vane control is changed from AUTO to MANUAL.
(c) When the SWING is finished.
(d) When the test run starts.
(e) When the power supply turns ON.
(4) VANE AUTO ( ) mode
In VANE AUTO mode, the microprocessor automatically determines the horizontal vane angle and operation to make the
optimum room-temperature distribution.
(5) STOP (operation OFF) and ON-TIMER standby.
When the following cases occur, the horizontal vane returns to the closed position.
(a) When the OPERATE/STOP(ON/OFF) button is pressed (POWER OFF).
(b) When the operation is stopped by the emergency operation.
(c) When the ON-TIMER is on standby.
1In COOL and DRY operation
2In FAN operation
Vane angle is fixed to Angle 1.
Vane angle is fixed to Angle 4.
(6) Dew prevention
During COOL or DRY operation at Vane Angle 4 or 5 when the compressor cumulative operation time exceeds 1 hour,
the vane angle automatically changes to Angle 1 for dew prevention.
(7) SWING MODE ( )
By selecting SWING mode with the VANE button, the horizontal vane swings vertically. The remote controller displays
“”.
(8) LONG MODE ( )
By pressing the LONG button indoor fan speed becomes faster than setting fan speed on the remote controller, and the
horizontal vane moves to the position for LONG mode. The remote controller displays “ ”. LONG mode is cancelled
when the LONG button is pressed once again or the VANE button is pressed.
AUTO
Horizontal Middle Downward Swing
8-6. AUTO VANE OPERATION
1. Horizontal vane
(1) Vane motor drive
This model is equipped with a stepping motor for the horizontal vane. The rotating direction, speed, and angle of the
motor are controlled by pulse signals (approx. 12V) transmitted from microprocessor.
(2) The horizontal vane angle and mode change as follows by pressing the VANE button.
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