Mitsubishi Electric MS-18NV, MU-18NV, MS-18NV-E4, MS-18NV-E4WH, MU-18NV-E Service Manual

SERVICE MANUAL
SPLIT-TYPE AIR CONDITIONERS
CONTENTS
1. TECHNICAL CHANGES ····································2
2. PART NAMES AND FUNCTIONS······················2
3. SPECIFICATION·················································4
4. OUTLINES AND DIMENSIONS·························5
6. REFRIGERANT SYSTEM DIAGRAM················7
7. PERFORMANCE CURVES································8
8. MICROPROCESSOR CONTROL ····················10
9. SERVICE FUNCTIONS ····································16
10. TROUBLESHOOTING······································18
11. DISASSEMBLY INSTRUCTIONS ·····················24
12. PARTS LIST······················································28
13. OPTIONAL PARTS ···········································31
Wireless type Models
MS-18NV -
(WH)
· MU-18NV -
E4E4
No. OB228
MS-18NV -
E4
2
TECHNICAL CHANGES
MS-18NV - MS-18NV -
1. Indoor electronic control P.C. board has changed.
MU-18NV - MU-18NV -
1. Compressor has changed.(NH-33VMDTPH-33VPET)
2. Outdoor heat exchanger has changed.
3. Refrigerant filling capacity(R-22) has changed.(1.65kg1.05kg)
E4E3
E4E3
1
PART NAMES AND FUNCTIONS
2
INDOOR UNIT
Remote control receiving section
Air cleaning filter(option)
Deodorizing filter(option)
Grille
(When the grille is open)
MS-18NV -
E4
3
TEMPERATURE buttons
Signal transmitting section
Operation display section
OPERATE /STOP
(ON /OFF)button
OPERATION SELECT button
FAN SPEED CONTROL button
SLEEP button
ON-TIMER button
CLOCK SET button
HR. button
MIN. button
(TIME SET button)
VANE CONTROL button
OFF-TIMER button
RESET button
SWING buttons
MS-18NV -
E4
OUTDOOR UNIT MU-18NV -
E4
REMOTE CONTROLLER
4
NOTE:Test conditions
Cooling : Indoor DB27: / WB19:
Outdoor DB35: / WB24:
SPECIFICATION
3
Capacity
Electrical data
Compressor
Indoor
fan motor
Outdoor
fan motor
Dimensions
Weight
Special remarks
Model
Function
Power supply
Coefficient of performance(C.O.P)
Capacity Dehumidification Air flow(Hi) Power outlet Running current Power input Auxiliary heater Power factor Starting current Compressor motor current Fan motor current
Model Output Winding resistance(at20:) Model Winding resistance(at20:) Model Winding resistance(at20:)
Indoor unit
Outdoor unit
Indoor unit Outdoor unit Air direction Sound level (Hi) Fan speed (Hi) Fan speed regulator Refrigerant filling capacity(R-22) Refrigerating oil (Model)
Thermistor
Width Height Depth Width Height Depth
Indoor unit Outdoor unit Indoor unit Outdoor unit Indoor unit Outdoor unit
RT11(at25:) RT12(at25:)
kW
R/h
K /h
A A
W
A(kW)
%
A A A
W
"
"
"
mm mm mm mm mm mm
kg kg
dB
dB rpm rpm
kg
cc k" k"
MS-18NV -
E4
Single phase, 220-240V, 50Hz
WHT-BLK183.8 BLK-RED250.5
1,015
320 190 850 605 290
14
5
4
10 10
Cooling
5.1
2.5
INDOOR 756 / OUTDOOR 2340-2400
15
9.1
1,910-2,010
95-92 51-55
8.46
INDOOR 0.25 / OUTDOOR 0.39
2.67-2.54
PH-33VPET
1,500
C-R1.08
C-S 2.18
RA4V27-EA or EF
RA6V50-OF or OG
WHT-BLK116.4 BLK-RED111
48
42 52
1,180
830-860
1
1.05
900 (MS32N1)
5
OUTLINES AND DIMENSIONS
4
MS-18NV -
E4
MU-18NV -
E4
OUTDOOR UNIT
INDOOR UNIT
3 297
450 450
352438
254
20
60
40
150 648 217
5190
995
19077550
320
1015
17.5
160
56
4holes 11o20
Indoor unit
Installation plate
Wireless remote controller
Power supply cord Lead to right 2m Lead to left 1m
Wall hole [75
Installation plate
Liquid line [8-0.5m Gas line [12-0.43m Insulation [50 O.D
[28 I.D
Insulation [28
Drain hose [16
Air out
{
Air in
If the right/left sides or back side is vacant,the front has only to be 50cm unobstructed.
If the front or right/left sides are vacant, the top has only to be 10cm unobstructed.
Unit : mm
6
WIRING DIAGRAM
5
MU-18NV -
E4
MODEL WIRING DIAGRAM
OUTDOOR UNIT
NOTE:1. Use copper conductors only.(For field wiring)
2. “w”show 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
1.Slide the sleeve.
2.Pull the wire while pushing the locking lever.
SYMBOL
C1 C2
SYMBOL
F
MC
SYMBOL
MF
TB
NAME
NAME NAME COMPRESSOR CAPACITOR OUTDOOR FAN CAPACITOR
FUSE(2A) COMPRESSOR(INNER THERMOSTAT)
OUTDOOR FAN MOTOR(INNER THEMOSTAT) TERMINAL BLOCK
MS-18NV -
E4
MODEL WIRING DIAGRAM
INDOOR UNIT
SYMBOL
RT12
TB
52C
SYMBOL
IC141
MF MV
NR11
RT11
SYMBOL
C11
DSAR
F11
F12
HIC1
NAME
NAME NAME INDOOR FAN CAPACITOR SURGE ABSORBER FUSE(3.15A) THERMAL FUSE(93¡C) DC / DC CONVERTER
HYBRID IC INDOOR FAN MOTOR VANE MOTOR VARISTOR ROOM TEMPERATURE THERMIST OR
INDOOR COIL THERMISTOR TERMINAL BLOCK CONTACTOR
NOTE: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
MF
BLK
WHT
RED ORN
N
220-240V~
BLU
4
BLU
WHT
BLK
RED
C1
TB
WHT
ORN
F
C2
RED
WHT
1 2 3
GRN/YLW
FROM INDOOR UNIT CONNECTING
C
S
R
MC
2
w
w
CIRCUITBREAKER
50Hz
220-240V~
BRN
DSAR
GRN/YLW
LD1
REMOTE CONTROLLER
3 1
DISPLAY P.C.BOARD
101
CN
102
CN
151
CN
ELECTRONIC CONTROL P.C BOARD
BLU
RECEIVER P.C.BOARD
MV
5
F11
33
BLU
~/N 220-240V
CORD
POWER SUPPLY
T
O OUTDOOR UNIT CONNECTING
BRN
L
N
GRN/YLW
TB
52C
BRN
2
4
3
CN201
1
2
F12
WHT
BLU
BLU BLU
TRANS
HIC1
111
CN
4 2 1
C11
CN211
BLK
WHT
GRY RED
RT11
MF
3
121
CN
CN
112
NR11
IC141
RT12
YLW
BRN
w
w
w
w
w
w
7
REFRIGERANT SYSTEM DIAGRAM
6
MS-18NV -
E4
MU-18NV -
E4
INDOOR UNIT
OUTDOOR UNIT
Indoor heat exchanger
Room temperature thermistor RT11
Refrigerant pipe [15.88 (Option) (with heat insulator)
Flared connection
Indoor coil thermistor
RT12
Refrigerant pipe [6.35 (Option)
(with heat insulator)
Stop valve
Capillary tube [3.0X[2.0X700
Compressor
Accumulator
Stop valve (with service port)
Outdoor heat exchanger
Refrigerant flow in cooling
Strainer
Unit:mm
Distributor
Indoor unit
w Max. Height difference 5m
wHeight difference should be within 5m regardless of which unit, indoor or outdoor position is high.
Outdoor unit
Refrigerant Piping
Max.length
A
Model
Outdoor unit precharged
1050
Refrigerant piping length (one way)
15m
120
7m
0
10m
45
MS-18NV - E4
MAX. HEIGHT DIFFERENCE
ADDITIONAL REFRIGERANT CHARGE(R-22 : g)
Model
Refrigerant piping
Max. length : m
A
Piping size O.D : mm
Length of connecting pipe : m
Indoor unit
Gas 0.43
Liquid 0.5
Gas
15.88
Liquid
6.35
Outdoor unit
Gas 0
Liquid 0
MS-18NV -
E4
15
MAX. REFRIGERANT PIPING LENGTH
Calculation : Xg=15g/mO(A-7)m
8
PERFORMANCE CURVES
Wet and dry-bulb thermometers
Dry-bulb thermometers
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 provided to clarify the operating characteristics of the air conditioner under the conditions indicated by the performance curve.
(1) GUARANTEED VOLTAGE
Rated voltage : ±10% (198 ~ 264V
),50Hz
(2) AIR FLOW
Air flow should be set at MAX.
(3) MAIN READINGS
(1) Indoor intake air wet-bulb temperature :°CWB (2) Indoor outlet 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 outlet 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 inlet. 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 OPERATION switch 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
MS-18NV -
E4
9
MS-18NV - E4
11
Both indoor and outdoor unit are under the same temperature/humidity condition.
OUTDOOR LOW PRESSURE AND OUTDOOR UNIT CURRENT COOL operation
22
Air flow should be set at MAX.
33
The unit of pressure has been changed to MPa on the international system of units(SI unit system).
The conversion factor is : 1(MPa • G) =10.2(kgf/ff• G)
Dry-bulb temperature
Relative humidity(%)
20
50
25
60
30 70
15 20
50
256030
70(%)
35(:)
0.3
0.4
0.5
0.6
0.7
7
6
5
4
3
18 32
220V/240V
15 20
50
256030
70(%)
35(:)
6
7
8
9
10
11
220V/240V
18
32
MU-18NV -
E4
MU-18NV -
E4
Ambient temperature(˚C)Ambient humidity(%)
Ambient temperature(˚C)Ambient humidity(%)
Outdoor low pressure
(kgf/F•G)(MPa•G)
Outdoor unit current(A)
10
Once the operation mode are 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
OPERATION SELECT button.
(3) The operation mode is determined by the room
temperature at start-up of the operation.
MICROPROCESSOR CONTROL
8
lighting not lighting
About 2 :  or more
Difference betweeen set temperature and room temperature
About 2 :  or less
This shows that the air conditioner is operating to reach the target temperature. Please wait unitil the target temperature is obtained.
This shows that the room temperature is approaching the target temperature.
Operation state
Indication
Operation Indicator
Operation Indicator lamp
The operation indicator at the right side of the indoor unit indicates the operation state.
INDOOR UNIT DISPLAY SECTION
Example
Previous operation
COOL mode of “I FEEL CONTROL” or COOL 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 as the operation starts.
When the system is stopped with the OPERATE/STOP(ON/OFF) 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.
Example
Previous operation
COOL mode of “I FEEL CONTROL” or COOL mode
When the system is restarted after 2 hours and more, the operation mode is determined by the 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 room temperature at start-up of the operation.
MS-18NV -
E4
TEMPERATURE buttons
Signal transmitting section
Operation display section
OPERATE /STOP (ON /OFF)button
OPERATION SELECT button
FAN SPEED CONTROL button
SLEEP button
ON-TIMER button
CLOCK SET button
HR. button
MIN. button
(TIME SET button)
VANE CONTROL button
OFF-TIMER button
RESET button
SWING buttons
Initial room temperature
25: or more more than 13:,
less than 25:
mode
COOL mode of
“I FEEL CONTROL“
DRY mode of
“I FEEL CONTROL”
WIRELESS REMOTE CONTROLLER
11
Mode
COOL mode of
"I FEEL CONTROL"
DRY mode of
"I FEEL CONTROL"
Initial room temperature Initial set temperature
26: or more
25: to 26:
more than13:, less than 25:
24:
Initial room temperature minus 2: Initial room temperature minus 2:
w1
w 1 When the system is restarted with the remote controller, the system operates with the previous set temperature
regardless of the room temperature at restart. 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 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.
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. 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 : 2 degrees or more········································Hi Room temperature minus set temperature : Between 1 and 2 degrees····························Me Room temperature minus set temperature : less than 1 degree·······································Lo
2. 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 doesn’t work after 5 minutes since the compressor has started. Indoor fan operates at the set speed and the compressor stops for 5 minutes. After that, if RT12still reads below -1°C this mode is prolonged until the RT12 reads over -1°C.
2 Time 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 Lo or Me. c. Room temperature is below 26°C. 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 Hi or the room temperature exceeds 26°C. However, when two of the above conditions (b.and c.) are satisfied again.Time accumulation is resumed.
1 deg.
1.7 deg.
2 deg.
4 deg.
— COOL mode of “I FEEL CONTROL” —
Fan speed
Difference between room temperature and set temperature during
12
Compressor Outdoor fan
OFF
ON
(continuously at set speed)
Indoor fan
ON
ON
OFF
—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 Lo.
2. The operation of the compressor and indoor fan/ outdoor fan
Compressor operates by room temperature control and time control.
Set temperature is controlled to fall 2°C from initial room temperature.
Indoor fan and outdoor fan operate in the same cycle as the compressor.
• When the room temperature is 23°C 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 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.
Operation time chart
Example
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 Lo.
Thermostat
Indoor fan
Outdoor fan compressor
1st ON
8 min.
1 min.
3 min.
2nd ON
OFF
OFF
OFF
OFF
OFF
ON
ON
ON
ON
ON
ON
Operation chart
Example
13
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 the TEMPERATURES button.
(TOO WARM or TOO COOL button) to select the desired temperature. The setting range is 16 ~ 31°C. w Indoor fan continues to operate regardless
of thermostat’s OFF-ON at set speed.
w Coil frost prevention is as same as COOL
mode of “I FEEL CONTROL”.
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 temperature 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 temperature is 13°C or below. (5) When DRY operation functions, the fan speed is lower than cool operation.
SLEEP
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 (Hi,Me,Lo,SLEEP), 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 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. (See page 19.)
8-4.FAN( d )OPERATION
(1) Press OPERATE/STOP(ON/OFF) button. (2) Select FAN mode with the OPERATION SELECT button. (3) Select the desired fan speed.When AUTO, it becomes Lo.
Only indoor fan operates.Outdoor unit does not operate.
8-6. AUTO VANE OPERATION
(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 (approx. 12V) transmitted from indoor microprocessor. (2) The horizontal vane angle and mode changes as follows by pressing the VANE CONTROL ( ) button.
14
(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. (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 vane angle and operation to make the optimum room-temperature distribution.
(5) 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.
(6) SWING MODE ( )
By pressing the SWING button ( ),the horizontal vane swings vertically. The remote controller displays “ ”. SWING mode is cancelled when the SWING button or VANE CONTROLbutton ( ) is pressed the mode is changed.
1 In COOL and DRY operation
2 In FAN operation
Vane angle is fixed to Angle 1.
Vane angle is fixed to Angle 4.
8-7. SLEEP MODE ()
• When the SLEEP button ( ) is pressed, the indoor fan speed drops and the air flow sound from the indoor unit is decreased.
• The indications of the remote controller are “ ” and “ ”.
• When the FAN SPEED CONTROL button ( ) or the SLEEP button ( ) or mode change button is pressed during the SLEEP mode, the SLEEP mode is released.
8-8. TIMER OPERATION
1. How to set the timer
(1) Press OPERATE/STOP(ON/OFF) button to start the air conditioner. (2) Check that the current time is set correctly. NOTE : Timer operation will not work without setting the current time. Initially “AM0:00” blinks at the current time display of
TIMER MONITOR, so set the current time correctly with CLOCK SET button.
(3) Press TIMER CONTROL button to select the operation.
” button... AUTO START operation (ON timer) “ ” button... AUTO STOP operation (OFF timer)
(4) Press HR. and MIN. button to set the timer. Time setting is 10-minute units.
HR. and MIN. button will work when “ ” or “ ” mark is flashing. These marks disappear in 1 minute. After setting the ON timer, check that Operation Indicator lamp of the indoor unit lights.
NOTE1 : Be sure to place the remote controller at the position where its signal can reach the air conditioner even during
TIMER operation, or the set time may deviate within the range of about 10 minutes.
NOTE2 : Reset the timer in the following cases, or the set time may deviate and other malfunctions may occur.
A power failure occurs.
The circuit breaker functions.
15
2. Cancel
Timer setting can be cancelled with the TIMER CONTROL buttons. (“ ” or “ ”) To cancel the ON timer, press the “ ” button.
To cancel the OFF timer, press the “ ” button. Timer is cancelled and the display of set time disappears.
PROGRAM TIMER
(Example 1) The current time is 8:00 PM.
The unit turns off at 11:00 PM, and on at 6:00 AM.
The OFF timer and ON timer can be used in combination.
”and “ ” display shows the order of the OFF timer and ON timer operation.
(Example 2) The current time is 11:00 AM.
The unit turns on at 5:00 PM, and off at 9:00 PM.
NOTE : TIMER setting will be cancelled by power failure or breaker functioning.
8-9. EMERGENCY-TEST OPERATION
When the remote controller is missing, has failed or when the batteries run down, press the EMERGENCY OPERATION switch on the front of the indoor unit. The unit will start and the Operation Indicator lamp will light. The first 30 minutes of operation is the test run operation. This operation is for servicing. The indoor fan speed runs at high notch and the system is in continuous operation. (The thermostat is ON.) After 30 minutes of test run operation the system shifts to EMERGENCY COOL MODE with a set temperature of 24°C. The fan shifts to Me notch. This operation continues until the EMERGENCY OPERATION switch is pressed again or the unit receives any signal from the remote controller. In case of latter normal operation will start. The coil frost prevention works even in this operation. In the test run or Emergency operation, the horizontal vane operates in VANE AUTO mode.
NOTE : Do not press the EMERGENCY OPERATION switch during normal operation.
EMERGENCY OPERATION switch
Press once <Cool> Press again <Stop>
Operation Indicator lamp
SERVICE FUNCTIONS
16
9
9-2. P.C. BOARD MODIFICATION FOR INDIVIDUAL OPERATION
A maximum of 4 indoor units with wireless remote controllers can be used in a room. In this case, to operate each indoor unit individually by each remote controller, P.C. boards of remote controller must be modified according to the number of the indoor unit.
9-1. TIMER SHORT MODE
For service, set time can be shortened by short circuit of JPG and JPS on the electronics control P.C. board. The time will be shortened as follows. 3-minutes delay : 3-minutes 3-seconds. AUTO START : 1 hour 1-minute AUTO STOP : 1 hour 1-minute
Short the connector during the timer mode.
}
How to modify the remote controller P.C. board
Remove batteries before modification. The board has a print as shown below :
The P.C.board has the print “J1” and “J2”. Jumper wires are mounted to each “J1” and “J2”. Cut J1 and J2 according to the number of indoor unit as shown in Table 1.. After modification,push the reset button.
NOTE : For remodelling, take out
the batteries at first. After finish remodelling, put back the batteries then push the RESET button.
No. 1 unit No. 2 unit No. 3 unit
No. 4 unit
1 unit operation No modification
– –
2 units operation
Same as at left
Cut J1
3 units operation
Same as at left Same as at left
Cut J2
4 units operation
Same as at left Same as at left Same as at left
Cut both J1 and J2
Table 1.
NOTE :
At power supply failure or installation, indoor unit deletes the memory about remote controller. When the power supply is turned on and indoor unit receives the first signals from the remote controller, the remote controller number is designated as the indoor unit number. Therefore at and after the second time indoor unit accepts the remote controller of the initial setting number. At setting-error, turn the power supply off to cancel the individual operation, and then turn the power supply on to restart the setting.
MS-18NV -
E4
17
9-3. AUTO RESTART FUNCTION
When the indoor unit is controlled with the remote controller, the operation mode, set temperature, and the fan speed are memorized by the indoor electronic control P.C.board. The “AUTO RESTART FUNCTION” sets to work the moment power has restored after power failure.Then, the unit will restart automatically. However if the unit is operated in “I FEEL CONTROL.” mode before power failure, the operation is not memorized. In “I FEEL CONTROL.” mode, the operation is decided by the initial room temperature.
How to set “AUTO RESTART FUNCTION”
1Turn off the main power for the unit. 2Remove the electronic control P.C. board and the display P.C.board.(See page 24.) 3Cut the RESISTOR JR06 on the indoor electronic control P.C.board.
JR06
CN102
CN151
CN112 CN111CN121
CN101
BZ
SW
52C
IC101 RA102
IC141
CN211
C11CN201
Operation
1If the main power (220/240V AC) has been cut, the operation settings remain. 2After 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.)
NOTE:
The operation settings are memorized when 10 seconds have passed after the indoor unit was operated with the remote
controller.
If main power is turned off or a power failure occurs while AUTO START/STOP timer is active, the timer setting is
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 off due to the rush of starting current, systematize other home appliances not to turn on at the same
time.
When some air conditioners are connected under the same power system,compressor starting current as large
as that for all the compressors used flows at a time as soon as the units restart automatically. Therefore, the specific counter-measures are required to prevent main voltage drop or the rush of starting current by providing the system to allow the units to start in regular succession.
18
10 TROUBLESHOOTING
10-1. Cautions on troubleshooting
1. Before troubleshooting, check the following:
1) Check the power supply voltage.
2) Check the indoor/outdoor connecting wire for mis-wiring.
2. Take care the following during servicing.
1) Before servicing the air conditioner, be sure to first turn off the remote controller to stop the unit, and then after confirming the horizontal vane is closed, turn off the breaker and / or disconnect the power plug.
2) When removing the electronic control P.C. board, hold the edge of the board with care NOT to apply stress on the components.
3) When connecting or disconnecting the connectors, hold the housing of the connector. DO NOT pull the lead wires.
3. Troubleshooting procedure
1) First, check if the OPERATION INDICATOR lamp on the indoor unit is flashing on and off to indicate an abnormality. To make sure, check the abnormality indication for 2 or 3 times before starting service work.
2) If the electronic control P.C. board is supposed to be defective, check the copper foil pattern for disconnection and the components for bursting and discoloration.
3) When troubleshooting, refer to the flow chart and the check table on page 19.
4. How to replace batteries
Weak batteries may cause the remote controller malfunction. In this case, the remote controller can not be repaired only by the battery replacement. To operate the remote controller normally, discharge the remote controller in the following order. This remote controller has the RESET button. After refilling new batteries, press the RESET button with tip end of ball point pen or the like, and then use the remote controller.
MS-18NV -
E4
RESET button
19
10-2. Instruction of troubleshooting
Indoor unit operates. Outdoor unit doesn’t
Outdoor unit operates in only Test Run operation.
Outdoor unit doesn’t operate even in Test Run operation.
Check room temperature thermistor.
Refer to “Check of outdoor unit” on page 22.
Indoor unit doesn’t receive the signal from remote controller.
Refer to “Check
of remote controller and receiver P.C. board” on page 21.
Operation Indicator lamp on the indoor unit is flashing on and off.
Indoor unit doesn’t receive the signal from remote controller. Also, Operation Indicator lamp doesn’t flash, when the EMERGENCY OPERATION switch is pressed.
Refer to “Check of indoor electronic control P.C. board” on page 22.
Cause:Indoor unit 2-time-Room temperature/Indoor coil thermistor trouble 3-time-Indoor fan motor trouble
D
B
Check room temperature thermistor. Refer to“Test point diagram and voltage” on page 23.
Refer to “Check of indoor fan motor” on page 21.
Check indoor coil thermistor. Refer to“Test point diagram and voltage” on page
23.
2-time flash
2.5-second OFF 3-time flash
2.5-second OFF
Start
C
A
1. troubleshooting check table
Operation Indicator
w Before taking measures, make sure that the symptom reappears for accurate troubleshooting.
Self check table
NO.
1
2
Abnormal
point
Indoor coil thermistor
Room temperatur e thermistor
Indoor fan motor
Indication
2-time flash
2.5-second OFF
3-time flash
2.5-second OFF
Symptom
Outdoor unit does not run.
Indoor fan motor repeats 12 seconds ON and 3 minutes OFF. When the indoor fan motor breaks, the fan keeps stopping.
Detect method
Detect Indoor coil/room temperature thermistor short or open circuit every 8 seconds during operation.
When rotational frequency feedback signal is not emit during 12-second indoor fan operation
Check point
Check thermistor calibration.
Reconnect connector.
Check indoor electronic control P.C.
board.
Disconnect connector CN211 and then check connector CN121 2 - 3 to make
sure rotational frequency feedback signal of 1.5V or over exists.
Check indoor electronic control P.C. board.
Check indoor fan motor.
Reconnect connector.
20
Measure the resistance between the terminals with a tester. (Coil wiring temperature –10°C ~ 40°C)
Measure the resistance between the terminals with a tester. (Coil wiring temperature –10°C ~ 40°C)
Measure the resistance between the terminals with a tester. (Coil wiring temperature10°C ~ 30°C)
Compressor
Room temperature thermistor
2. Trouble criterion of main parts
Part name
Indoor coil thermistor
Indoor fan motor
Motor part
Sensor part
Outdoor fan motor
Vane motor
Check method and criterion
Measure the resistance with a tester. (Part temperature 10°C ~ 30°C)
Measure the voltage Power ON.
Measure the resistance between the terminals with a tester. (Part temperature10°C ~ 30°C)
Figure
P
~
BLK
R
MAIN
AUX
RED
S
C
WHT
MAIN
AUX
FUSE
BLK
RED
WHT
GRY
YLW
BRN
MAIN
AUX
BLK
RED
WHTORN
P
YLW
RED
BLU
ORN
PNK
ROTOR
INNER PROTECTOR
P
Normal
8k½ ~ 20k½
Abnormal
Opened or short-circuited
Normal
0.95 ~ 1.17½
1.92 ~ 2.36½
C-R C-S
Normal
Abnormal
Opened or
short-circuited
176 ~ 192½ 240 ~ 261½
WHT-BLK
BLK-RED
BRN-YLW
YLW-GRY
Normal
4.5 ~ 5.5V
Abnormal
Remain 0V or 5V
(When fan revolved one time)
0V5V0V
(Approx.)
Normal
Abnormal
Opened or
short-circuited
WHT-BLK BLK-RED
Normal
Abnormal
Opened or short-circuited
358 ~ 388½
Abnormal
Opened or
short-circuited
MS-18NV -
E4
102 ~ 126½
97.9 ~ 120½
21
Replace the receiver P.C. board.
Replace the remote controller.
Replace the batteries.(See page 18.)
Switch on the remote controller.
Repair the indoor fan motor.
Resolder it.
Disconnect lead wires from connector CN211 on the indoor electronic control P.C. board. Measure resistance between lead wires No.1 and No.4 and then No.1 and No.2.
Turn OFF the power supply. Check connector CN211 visually.
Reconnect the lead wires.
Yes
Yes
Check of indoor fan motor
A
Check of remote controller and receiver P.C. board
B
Indoor fan does not operate.
Are lead wires connected?
Is soldered point normal?
Insert screwdriver into air outlet to rotate indoor fan motor slowly for 1 revolution or over, and measure voltage No.2(+) and No.3(-) on CN121.
Is resistance 0 (short circuit) or ° (open circuit)?
Indoor unit operates by pressing the EMERGENCY OPERATION switch, but does not operate with the remote controller.
Turn on a radio to AM and press switch on the remote controller.
Is noise heard from radio?
Are there any fluorescent lights of
inverter or rapid-start type within the range of 1m?
Turn ON the power supply. Measure the voltage between receiver P.C. board connector No.2
(+)
and No.1when remote controller button is
pressed.
Is the voltage approx. 4V DC?
Replace the indoor electronic control P.C. board.
Re-install the unit away from lights.
Attach a filter on receiving part.
Yes ( 0 or ° )
No
(others)
Yes
No
Yes
No
Is LCD display on the remote controller visible?
Remove the batteries and then set them back. Check if the unit operates with the remote controller.
Yes
Does the unit operate with the remote controller?
Yes
OK
No (not clear)
Yes
No
No
No(5V or 0V DC)
No
wCheck if the remote controller is exclusive for this air conditioner.
Replace the indoor electronic control P.C. board.
Does voltage repeat 0V DC and 5V DC?
Yes
No
22
Check the continuity of indoor and outdoor unit
Replace the indoor electronic control P.C. board.
Check of indoor electronic control P.C. board
C
The unit doesn’t operate with the remote controller. Also, the OPERATION INDICATOR lamp doesn’t light up by pressing the EMERGENCY OPERATION switch.
Check of outdoor unit
D
Compressor and outdoor fan do not operate.(Only indoor fan operates.)
Check the voltage to terminal block of outdoor unit. Is there 220-240V AC to terminal block between 2 - N ?
Press the EMERGENCY OPERATION switch. 3-minute time delay works. Test run operation operates for 30 minutes.
Start
Check the voltage to terminal block of indoor unit. Is there 220-240V AC to terminal block between 2 - N ?
No
Yes
No
Yes
Check the outdoor wiring, the outdoor fan motor and compressor.
Check the both “parts side”and “pattern side” of indoor electronic control P.C. board visually.
Replace the fuse.
Is fuse(F11) blown?
Be sure to check both fuse and varistor in any case.
Replace the fan motor .
Trouble of the indoor electronic control P.C. board.
Is winding resistance of fan motor 0 "?
Is winding resistance of vane motor 0 "?
No
Yes
Replace the vane motor.
No
Yes
Yes
Is varistor(NR11) burnt?
Replace the varistor.
Yes
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.
No
No
The unit doesn’t operate with the remote controller. Also, the Operation Indicator lamp doesn’t light up by pressing the EMERGENCY OPERATION switch.
No
Yes
1.Pull out the power supply cord.
2.Measure resistance between CN201
1 on
the indoor electronic control P.C. board and
N on the terminal
block with a tester.
Is resistance 0"?
Trouble of fuse (F12)
CN201
2
1
L N
F12
1
3
Terminal block
Be sure to check both fresistance.
Yes
No
23
TEST POINT DIAGRAM AND VOLTAGE MS-18NV ­Indoor electronic control P.C. board
E4
}
}
}
}
Fan motor power supply
Fuse 250V AC 3.15A
Power supply input
220-240V AC
+
--
5V DC
Indoor coil thermistor(RT12)
Timer short mode point
Emergency operation switch
12V DC
+
--
Room temperature thermistor(RT11)
Room temperature thermistor (RT11) Indoor coil thermistor (RT12)
C144
C144
JPG JP45
Auto restart function Cut the Resistor JR06. (Refer page 17.)
24
DISASSEMBLY INSTRUCTIONS
11
(1)
(2)
1Slide the sleeve. 2Pull the terminal while
pushing the locking lever.
1Hold the sleeve, and pull out the terminal slowly.
In case of a terminal with lock mechanism, detach the terminal as shown below.
<"Terminal with lock mechanism" Detaching points>
OPERATING PROCEDURE PHOTOS
1. Removing the front panel
(1) Remove the screws caps at the down of the front panel.
Remove the screws.
(2) Pull the panel down to your side slightly and unhook the
catches at the top.
2. Removing the electronic control P.C. board
(1) Remove the front panel. (Refer to 1) (2) Remove the electrical cover. (3) Remove the screw, remove the terminal cover. (4) Remove the screw on the terminal block. (5) Unhook the catch of the lamp holder. (6) Remove the receiver holder. (7) Disconnect the connectors and the lead wire from 52C
relay on the electronic control P.C. board and remove the ground and the indoor coil thermistor.
(8) Remove the electronic control P.C. board.
11-1. MS-18NV -
INDOOR UNIT
E4
Photo 2
Photo 1
Front panel
Screws
Screws
Terminal block screw
Indoor coil thermistor
Indoor electronic control P.C. board
Ground
25
OPERATING PROCEDURE PHOTOS
Photo 4
Photo 5
Heat exchanger
screw
Catch
Bearing support screws
Heat exchanger
Indoor fan motor
Line flow fan
Screws of motor band
Fan motor screws
3. Removing the electrical box
(1) Remove the front panel. (Refer to 1) (2) Remove the electrical cover. (3) Disconnect the connector of the indoor coil thermistor. (4) Disconnect the motor connector (CN211 and CN121) and
the vane motor connector (CN151) on the electronic control P.C. board.
(5) Remove the screw of the electrical box, remove the
electrical box.
4. Removing the indoor fan motor and the line flow fan
(1) Remove the front panel. (2) Remove the electrical box. (3) Unhook the catches on the both sides of the nozzle
assembly. (4) Remove the nozzle assembly. (5) Remove the screws of the bearing support. (6) Remove the screw of the heat exchanger unhook the
catch. (7) Lifting the heat exchanger, remove the bearing support. (8) Remove the motor support. (9) Loose the screw fixing the line flow fan, remove the line
flow fan. (
10
)
Remove the screws of the motor band, remove the fan
motor.
Photo 3
screw
screw
26
OPERATING PROCEDURE PHOTOS
1. Removing the cabinet
(1) Remove the screws of the cabinet. (2) Hold the bottom of the cabinet on the both side to remove
the cabinet.
2. Removing the electrical parts
(1) Remove the service panel and the cabinet. (2) Remove the following parts.
•Compressor capacitor (C1)
•Outdoor fan capacitor (C2)
•Terminal block
11-2. MU-18NV -
OUTDOOR UNIT
E4
Photo 1
Photo 3
Photo 2
Screws
Screws
Service panel
Compressor capacitor
27
PHOTOS
3. Removing the outdoor fan motor
(1) Remove the cabinet. (Refer to 1) (2) Disconnect the connector remove the hooked lead wire
from the fan motor. (3) Remove the propeller nut and remove the propeller fan. (4) Remove screws securing the fan motor.
4. Removing the compressor
(1) Remove the cabinet. (Refer to 1) (2) Remove the soundproof felt. (3) Remove the terminal cover on the compressor (4) Disconnect lead wires from the glass terminal of the
compressor. (5) Release gas from the refrigerant circuit. (6) Disconnect the welded part of the discharge pipe. (7) Disconnect the welded part of the suction pipe. (8) Remove nuts fixing the compressor. (9) Remove the compressor.
Photo 5
Compressor
Discharge pipe
Suction pipe
Compressor set nuts
Photo 4
Hook
Connector
Propeller fan
Propeller fan nut
Soundproof felt
OPERATING PROCEDURE
28
PARTS LIST12
MS-18NV - (WH) 12-1. INDOOR UNIT
STRUCTURAL PARTS
E4
E02 138 000 E02 138 010 E02 143 234 E02 141 100 E02 141 970 E02 143 067 E02 171 007
1 2 3 4 5 6 7
FRONT PANEL (WH) GRILLE (WH) BOX (WH) AIR FILTER INSTALLATION PLATE SCREW CAP (WH) LAMP PANEL (WH)
Symbol
in Wiring
Diagram
Q'ty/unit
3PCS/SET
RemarksPart No.
NO.
Part Name
1 1 1 2 1 3 1
MS-18NV-
E4
(WH)
Part number that is circled is not shown in the illustration.
Optional parts (See page 31.)
3
5
4
6
2
1
E02 141 620 E02 138 667 E02 138 666
8 9
10
INDOOR HEAT EXCHANGER UNION(LIQUID) UNION(GAS)
{6.35 {15.88
1 1 1
SCREW CAP
12-1. INDOOR UNIT STRUCTURAL PARTS
12-2. INDOOR UNIT
HEAT EXCHANGER
8
910
12-2. INDOOR UNIT HEAT EXCHANGER
29
MS-18NV - (WH) 12-3. INDOOR UNIT
FUNCTIONAL PARTS AND ELECTRICAL PARTS
E4
E02 143 235 E02 143 040 E02 141 702 E02 141 300 E02 001 505 E02 138 395 E02 443 452 E02 141 302 E02 141 303 E02 138 329 E02 141 509 E02 197 375 E02 085 385 E02 141 468 E02 001 504 E02 138 307 E02 138 308 E02 127 382 E02 205 381 E02 138 383
1 2 3 4 5 6 7 8
9 10 11 12 13 14 15 16 17 18 19 20
NOZZLE (WH) VANE (WH) DRAIN HOSE INDOOR FAN MOTOR RUBBER MOUNT POWER SUPPLY CORD ELECTRONIC CONTROL P.C. BOARD LINE FLOW FAN VANE MOTOR DISPLAY P.C. BOARD BEARING MOUNT TERMINAL BLOCK VARISTOR RECEIVER P. C. BOARD SLEEVE BEARING INDOOR COIL THERMISTOR ROOM TEMPERATURE THERMIST OR FUSE THERMAL FUSE SURGE ABSORBER
Symbol
in Wiring
Diagram
Q'ty/unit
1 1 1 1 2 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1
RA4V27 ­2PCS/SET
AUTO RESTART
3.15A 93:
Remarks
Part No.
NO.
Part Name
MF
MV
TB
NR11
RT12 RT11
F11 F12
DSAR
(WH)
MS-18NV-
E4
Part number that are circled are not shown in the illustration.
1
11
10
8
15
5
4
7
12
16
6
17
14
9
12-4. ACCESSORY PARTS AND REMOTE CONTROLLER
E02 138 426 E02 141 083
21 22
REMOTE CONTROLLER REMOTE CONTROLLER HOLDER
1 1
12-3. INDOOR UNIT FUNCTIONAL PARTS AND ELECTRICAL PARTS
3
2
SLEEVE BEARING
INDOOR COIL THERMISTOR
21 22
12-4. ACCESSORY P ARTS
AND REMOTE CONTROLLER
ROOM TEMPERATURE THERMISTOR
30
Symbol
in Wiring
Diagram
Q'ty/unit
Remarks
Part No.
NO.
Part Name
MU-18NV-
E4
E02 141 232 E02 141 521 E02 141 245 E02 217 630 E02 140 515 E02 217 900 E02 217 290 E02 144 301 E02 141 501 E02 082 353 E02 138 351 E02 197 374 E02 138 936 E02 138 506 E02 139 662 E02 150 661 E02 140 233 E02 095 382
1 2 3 4 5 6 7 8
9 10 11 12 13 14 15 16 17 18
CABINET GRILLE SERVICE PANEL OUTDOOR HEAT EXCHANGER MOTOR SUPPORT COMPRESSOR BASE OUTDOOR FAN MOTOR PROPELLER FAN COMPRESSOR CAPACITOR OUTDOOR FAN CAPACITOR TERMINAL BLOCK CAPILLARY TUBE COMPRESSOR RUBBER SET STOP VALVE(LIQUID) STOP VALVE(GAS) BACK PANEL FUSE
1 1 1 1 1 1 1 1 1 1 1 1 1 4 1 1 1 1
PH-33VPET
RA6V50 -
50+/440V
3.0+/440V
{3.0o{2.0o700 4RUBBERS/SET
{ 6.35 {15.88
250V/2A
MC
MF
C1 C2 TB
F
Part number that are circled are not shown in the illustration.
17
11
10
8
4
3
12
9
5
14
15 16
7
1
2
MU-18NV ­12-5. OUTDOOR UNIT
STRUCTURAL PARTS
E4
6
31
OPTIONAL PARTS13
Part No.
Model
MAC-1100FT
MS-18NV -
E4
Part No.
Model
MAC-1600DF
MS-18NV -
E4
Deodorizing filter (Gray sponge type)
Air cleaning filter (White bellows type)
13-1. AIR CLEANING FILTER
AIR CLEANING FILTER removes fine dust of 0.01 micron from air by means of static electricity.
Normal life of AIR CLEANING FILTER is 3 months. However, when it becomes dirty, replace it as soon as possible.
Clogged AIR CLEANING FILTER may reduce the air conditioner capacity or cause frost on the air outlet.
DO NOT reuse AIR CLEANING FILTER even if it is washed.
DO NOT remove or attach AIR CLEANING FILTER during unit operation.
13-2. DEODORIZING FILTER
DEODORIZING FILTER removes ammonia and hydrogen sulphide emitted from tobacco, and odor of pets.
Clean DEODORIZING FILTER every two weeks. If the filter is particularly dirty, clean the filter more often.
For cleaning, soak the filter in warm water for a while, and then wash and rinse it. Dry the filter in the shade
thoroughly.
When the filter color is still dark even after cleaning, replace the filter with a new one. Replace the filter at least once a year.
DEODORIZING FILTER and AIR CLEANING FILTER can be attached on either side.
HEAD OFFICE MITSUBISHI DENKI BLDG.MARUNOUCHI TOKYO100-8310 TELEX J24532 CABLE MELCO TOKYO
CC
Copyright 1999 MITSUBISHI ELECTRIC ENGINEERING CO.,LTD Issued in Jan. 1999. No.OB228 305 Printed in Japan
New publication, effective Jan. 1999 Specifications subject to change without notice.
Loading...