SPLIT-TYPE AIR CONDITIONERS

SERVICE MANUAL

Wireless type

Models

MS-18NV -

E4

(WH)

· MU-18NV -

E4

No. OB228

MS-18NV -

E4

CONTENTS

1. TECHNICAL CHANGES ····································2

2. PART NAMES AND FUNCTIONS······················2

3. SPECIFICATION·················································4

4. OUTLINES AND DIMENSIONS ·························5

5. WIRING DIAGRAM ············································6

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

1

TECHNICAL CHANGES

MS-18NV -

E3

➔

MS-18NV -

E4

1. Indoor electronic control P.C. board has changed.

MU-18NV -

E3

➔

MU-18NV -

E4

1. Compressor has changed.(NH-33VMDT ➔ PH-33VPET)

2. Outdoor heat exchanger has changed.

3. Refrigerant filling capacity(R-22) has changed.(1.65kg

➔ 1.05kg)

2 PART NAMES AND FUNCTIONS

INDOOR UNIT

MS-18NV -

E4

Air cleaning filter(option)

Deodorizing filter(option)

Grille

Remote control receiving section

(When the grille is open)

2

OUTDOOR UNIT

MU-18NV -

E4

REMOTE CONTROLLER

MS-18NV -

E4

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)

3

TEMPERATURE buttons

VANE CONTROL button

SWING buttons

OFF-TIMER button

RESET button

3 SPECIFICATION

Model

Function

Power supply

Capacity

Electrical data

Capacity

Dehumidification

Air flow(Hi)

Power outlet

Running current

Power input

Auxiliary heater

Power factor

Starting current

Compressor motor current

Fan motor current

Coefficient of performance(C.O.P)

Compressor

Model

Output

Indoor fan motor

Outdoor fan motor

Winding resistance(at20 : )

Model

Winding resistance(at20 : )

Model

Dimensions

Winding resistance(at20 : )

Width

Indoor unit Height

Depth

Outdoor unit

Width

Height

Weight

Special remarks

Depth

Indoor unit

Outdoor unit

Air direction

Sound level

(Hi)

Fan speed

(Hi)

Fan speed

Indoor unit

Outdoor unit

Indoor unit

Outdoor unit

Indoor unit regulator Outdoor unit

Refrigerant filling capacity(R-22)

Refrigerating oil (Model)

Thermistor

RT11(at25 : )

RT12(at25 : )

NOTE:Test conditions

Cooling : Indoor DB27 : / WB19 :

Outdoor DB35 : / WB24 : kW

R /h

K /h

A

A

W

A(kW)

%

A

A

A

W

"

" dB dB rpm rpm kg cc k k

"

"

" mm mm mm mm mm mm kg kg

MS-18NV -

E4

Cooling

Single phase, 220-240V, 50Hz

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

WHT-BLK183.8 BLK-RED250.5

RA6V50-OF or OG

WHT-BLK116.4 BLK-RED111

1,015

320

190

850

605

290

14

48

5

42

52

1,180

830-860

4

1

1.05

900 (MS32N1)

10

10

4

4 OUTLINES AND DIMENSIONS

MS-18NV -

E4

INDOOR UNIT

995

150

4holes 11 o

20

648

Indoor unit

217

Unit : mm

450

450

50

56

1015

775

17.5

Wireless remote controller

MU-18NV -

E4

OUTDOOR UNIT

438

Installation plate

190

352

5

Installation plate

Wall hole [ 75

Air in

{ Liquid line [ 8-0.5m

Gas line [ 12-0.43m

Insulation [ 50 O.D

[ 28 I.D

Drain hose [ 16

Insulation [ 28

190

Power supply cord

Lead to right 2m

Lead to left 1m

Air out

If the front or right/left sides are vacant, the top has only to be 10cm unobstructed.

If the right/left sides or back side is vacant,the front has only to be 50cm unobstructed.

5

5 WIRING DIAGRAM

MS-18NV -

E4

INDOOR UNIT

MODEL WIRING DIAGRAM

TO OUTDOOR

UNIT

CONNECTING

L

TB w

BRN w

BRN

220-240V~

2 w

WHT

POWER

SUPPLY

CORD

~/N 220-240V

50Hz

N w

BLU

5

HIC1

IC141

CN

112

BLU

F12

BRN

BLU

BLU

2

1

CN

101

LD1

CN

102

BLU

CN

151

CN201

3

1 w

4 w

3

52C

CN

121

TRANS

F11

ELECTRONIC CONTROL P.C BOARD

CN211

4

2

1

CN

111

3 3

MV

CIRCUITBREAKER

GRN/YLW

RECEIVER

P.C.BOARD

DISPLAY

P.C.BOARD

REMOTE

CONTROLLER

3

RT12

BRN

YLW

GRY

WHT

RED

BLK

MF

RT11

SYMBOL

C11

DSAR

F11

F12

HIC1

NAME

INDOOR FAN CAPACITOR

SURGE ABSORBER

FUSE(3.15A)

THERMAL FUSE(93 ¡ C)

DC / DC CONVERTER

SYMBOL

IC141

MF

MV

NR11

RT11

HYBRID IC

NAME

INDOOR FAN MOTOR

VANE MOTOR

VARISTOR

ROOM TEMPERATURE THERMISTOR

SYMBOL

RT12

TB

52C

NAME

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

MU-18NV -

E4

OUTDOOR UNIT

MODEL WIRING DIAGRAM

220-240V~ TB

2 w

WHT

FROM

INDOOR UNIT

CONNECTING

N w

BLU

WHT

C

C1

RED

S

MC

R

BLK

GRN/YLW

C2

RED

ORN

WHT

BLU

3

4

1

2

RED

ORN

WHT

BLK

MF

SYMBOL

C1

C2

NAME

COMPRESSOR CAPACITOR

OUTDOOR FAN CAPACITOR

SYMBOL

F

MC

NAME

FUSE(2A)

COMPRESSOR(INNER THERMOSTAT)

SYMBOL

MF

TB

NAME

OUTDOOR FAN MOTOR(INNER THEMOSTAT)

TERMINAL BLOCK

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.

6

6 REFRIGERANT SYSTEM DIAGRAM

MS-18NV -

E4

INDOOR UNIT

Unit:mm

MU-18NV -

E4

OUTDOOR UNIT

Refrigerant pipe [ 15.88

(Option)

(with heat insulator)

Accumulator

Indoor heat exchanger

Indoor coil thermistor

RT12

Distributor

Flared connection

Stop valve

(with service port)

Strainer

Outdoor heat exchanger

Compressor

Room temperature thermistor

RT11

Stop valve

Refrigerant pipe [ 6.35

(Option)

(with heat insulator)

MAX. REFRIGERANT PIPING LENGTH

Model

MS-18NV -

E4

Refrigerant piping

Max. length : m

A

15

MAX. HEIGHT DIFFERENCE

Indoor unit

Capillary tube

[ 3.0X

[ 2.0X700

Refrigerant flow in cooling

Piping size O.D : mm

Gas Liquid

15.88

6.35

Length of connecting pipe : m

Indoor unit

Gas 0.43

Liquid 0.5

Outdoor unit

Gas 0

Liquid 0 w Max. Height difference 5m

Refrigerant Piping

Max.length

A

Outdoor unit w Height difference should be within 5m regardless of which unit, indoor or outdoor position is high.

ADDITIONAL REFRIGERANT CHARGE(R-22 : g)

Model Outdoor unit precharged

7m

Refrigerant piping length (one way)

10m 15m

MS-18NV -

E4

1050 0 45 120

Calculation : Xg=15g/m O (A-7)m

7

7 PERFORMANCE CURVES

MS-18NV -

E4

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

(2) Indoor outlet air wet-bulb temperature

(3) Outdoor intake air dry-bulb temperature

(4) Total input

:°CWB

:°CWB

:°CDB

:W

}

Cooling

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.

INDOOR UNIT

Wet and dry-bulb thermometers

OUTDOOR UNIT

Dry-bulb thermometers

8

OUTDOOR LOW PRESSURE AND OUTDOOR UNIT CURRENT

COOL operation

1 Both indoor and outdoor unit are under the same temperature/humidity condition.

Dry-bulb temperature

20

25

30

Relative humidity(%)

50

60

70

2 Air flow should be set at MAX.

3 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/ f • G)

(kgf/ F •G)(MPa•G)

MU-18NV -

E4

0.7

7

6

0.6

5

0.5

4

0.4

220V/240V

3

0.3

15 18 20

50

25

60

30 32

70(%)

35( : )

Ambient temperature(˚C)Ambient humidity(%)

MU-18NV -

E4

11

10

9

8

7

220V/240V

6

15 18 20

50

25

60

30 32

70(%)

35( : )

Ambient temperature(˚C)Ambient humidity(%)

9

8 MICROPROCESSOR CONTROL

WIRELESS REMOTE CONTROLLER

Signal transmitting section

MS-18NV -

E4

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.

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)

TEMPERATURE buttons

VANE CONTROL button

SWING buttons

OFF-TIMER button

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.

RESET button

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”

INDOOR UNIT DISPLAY SECTION

Operation Indicator lamp

The operation indicator at the right side of the indoor unit indicates the operation state.

● 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

Operation Indicator

lighting not lighting

Previous operation

COOL mode of

“I FEEL CONTROL” or

COOL mode

Restart

COOL mode of

“I FEEL CONTROL”

Indication Operation state

Difference betweeen set temperature and room temperature

This shows that the air conditioner is operating to reach the target temperature.

Please wait unitil the target temperature is obtained.

About 2 : or more

This shows that the room temperature is approaching the target temperature.

About 2 or less

:

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.

Example

Previous operation

COOL mode of

“I FEEL CONTROL” or COOL mode

Restart

COOL or DRY mode of

“I FEEL CONTROL” that determined by room temperature at start-up of the operation.

10

(4) The initial set temperature is decided by the initial room temperature.

Mode Initial room temperature

26 : or more

Initial set temperature

24 :

COOL mode of

"I FEEL CONTROL"

DRY mode of

"I FEEL CONTROL"

25 : more than13

to 26

:

:

, less than 25 :

Initial room temperature minus 2 :

Initial room temperature minus 2 : 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.

w 1

(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)

— COOL mode of “I FEEL CONTROL” —

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 Fan speed

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

Difference between room temperature and set temperature during

2 deg. 4 deg.

1 deg. 1.7 deg.

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.

11

Operation chart

Example

Compressor

Outdoor fan

Indoor fan

OFF

ON

ON

(continuously at set speed)

OFF

ON

—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

1st ON 2nd ON

OFF

Thermostat

Indoor fan

Outdoor fan compressor

ON

ON

ON ON

OFF OFF

ON

OFF

3 min.

OFF

ON

1 min.

8 min.

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.

12

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.

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.

8-5. 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.

SLEEP

(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.)

8-6. 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.

13

(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.

1 In COOL and DRY operation

Vane angle is fixed to Angle 1.

2 In FAN operation

Vane angle is fixed to Angle 4.

(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 CONTROL button ( ) is pressed the mode is changed.

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.

14

2. Cancel

Timer setting can be cancelled with the TIMER CONTROL buttons. (“

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.

” or “ ”)

PROGRAM TIMER

● 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 1) The current time is 8:00 PM.

The unit turns off at 11:00 PM, and on at 6:00 AM.

(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.

Operation Indicator lamp

Press once <Cool>

Press again <Stop>

EMERGENCY OPERATION switch

15

9 SERVICE FUNCTIONS

MS-18NV -

E4

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.

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.

How to modify the remote controller P.C. board

Remove batteries before modification.

The board has a print as shown below :

NOTE : For remodelling, take out the batteries at first.

After finish remodelling, put back the batteries then push the RESET button.

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.

Table 1.

No. 1 unit

No. 2 unit

No. 3 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

No. 4 unit – – – Cut both J1 and J2

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.

16

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”

1 Turn off the main power for the unit.

2 Remove the electronic control P.C. board and the display P.C.board.(See page 24.)

3 Cut the RESISTOR JR06 on the indoor electronic control P.C.board.

IC141

CN21

1

IC101 RA102

JR06

Operation

1 If the main power (220/240V AC) has been cut, the operation settings remain.

2 After the power is restored, the unit restarts automatically according to the memory.(However, it takes at least 3 minutes for the compressor to start running.)

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.

17

10 TROUBLESHOOTING

MS-18NV -

E4

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.

RESET button

18

10-2. Instruction of troubleshooting

Start

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.

Indoor unit doesn’t receive the signal from remote controller.

Operation Indicator lamp on the indoor unit is flashing on and off.

of remote controller and receiver P.C.

board” on page 21.

2-time flash

2.5-second OFF

3-time flash

2.5-second OFF

Check room temperature thermistor.

Refer to

“Check of

D outdoor unit” on page 22.

Cause:Indoor unit

Indoor unit doesn’t receive the signal from remote controller.

Also, Operation Indicator lamp doesn’t flash, when the EMERGENCY

OPERATION switch is pressed.

indoor electronic control

P.C. board” on page 22.

2-time-Room temperature/Indoor coil thermistor trouble

3-time-Indoor fan motor trouble

Check indoor coil thermistor. Refer to“Test point diagram and voltage” on page

23.

Refer to A

“Check of indoor fan motor” on page 21.

Check room temperature thermistor. Refer to“Test point diagram and voltage” on page 23.

1. troubleshooting check table

Operation Indicator w

Before taking measures, make sure that the symptom reappears for accurate troubleshooting.

Self check table

NO.

Abnormal point

Indication Symptom Detect method

Indoor coil thermistor

1

Room temperatur e thermistor

2-time flash

2.5-second OFF

Outdoor unit does not run.

Check point

Detect Indoor coil/room temperature thermistor short or open circuit every 8 seconds during operation.

● Check thermistor calibration.

● Reconnect connector.

● Check indoor electronic control P.C. board.

2

Indoor fan motor

3-time flash

2.5-second OFF

Indoor fan motor repeats 12 seconds ON and

3 minutes OFF.

When the indoor fan motor breaks, the fan keeps stopping.

When rotational frequency feedback signal is not emit during 12-second indoor fan operation

● 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.

19

MS-18NV -

E4

2. Trouble criterion of main parts

Part name

Room temperature thermistor

Indoor coil thermistor

Check method and criterion

Measure the resistance with a tester.

(Part temperature 10°C ~ 30°C)

Normal

8k ½ ~ 20k ½

Abnormal

Opened or short-circuited

Measure the resistance between the terminals with a tester.

(Coil wiring temperature –10°C ~ 40°C)

Compressor

C-R

C-S

Normal

0.95 ~ 1.17

½

1.92 ~ 2.36

½

Abnormal

Opened or short-circuited

Measure the resistance between the terminals with a tester.

(Coil wiring temperature10°C ~ 30°C)

Indoor fan motor

WHT-BLK

BLK-RED

Normal

176 ~ 192 ½

240 ~ 261 ½

Abnormal

Opened or short-circuited

Measure the voltage Power ON.

BRN-YLW

YLW-GRY

Normal

4.5 ~ 5.5V

(When fan revolved one time)

0V ➔ 5V ➔ 0V

(Approx.)

Abnormal

Remain 0V or 5V

Outdoor fan motor

Measure the resistance between the terminals with a tester.

(Coil wiring temperature –10°C ~ 40°C)

WHT-BLK

BLK-RED

Normal

102 ~ 126 ½

97.9 ~ 120 ½

Abnormal

Opened or short-circuited

Figure

WHT C

S

AUX

P

MAIN

R

BLK

~

RED

FUSE

MAIN

AUX

P

MAIN

AUX

BLK RED ORN WHT

Vane motor

Measure the resistance between the terminals with a tester.

(Part temperature10°C ~ 30°C)

Normal Abnormal

358 ~ 388 ½ Opened or short-circuited

20

PNK

ROTOR

ORN

RED

YLW BLU

P INNER PROTECTOR

A Check of indoor fan motor

Indoor fan does not operate.

Turn OFF the power supply.

Check connector CN211 visually.

No Yes

Are lead wires connected?

Is soldered point normal?

Yes

Reconnect the lead wires.

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.

No

Resolder it.

Is resistance 0 (short circuit) or ° (open circuit)?

Yes ( 0 or

°

)

No

(others)

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.

Repair the indoor fan motor.

No

Does voltage repeat 0V DC and 5V DC?

Yes

Replace the indoor electronic control P.C. board.

B Check of remote controller and receiver P.C. board

Indoor unit operates by pressing the EMERGENCY OPERATION switch, but does not operate with the remote controller.

w Check if the remote controller is exclusive for this air conditioner.

Switch on the remote controller.

Is LCD display on the remote controller visible?

Yes

Remove the batteries and then set them back. Check if the unit operates with the remote controller.

No

(not clear)

Replace the batteries.(See page 18.)

Does the unit operate with the remote controller?

OK

Yes

No Turn on a radio to AM and press switch on the remote controller.

No

Is noise heard from radio?

Yes

Are there any fluorescent lights of inverter or rapid-start type within the range of 1m?

Yes ●

●

Replace the remote controller.

Re-install the unit away from lights.

Attach a filter on receiving part.

No

Turn ON the power supply.

Measure the voltage between receiver P.C. board connector No.2

(+) and No.1when remote controller button is pressed.

Yes

Replace the indoor electronic control P.C.

board.

Is the voltage approx. 4V DC?

No(5V or 0V DC)

Replace the receiver P.C. board.

21

C Check of indoor electronic control P.C. board

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 the both “parts side”and “pattern side” of indoor electronic control P.C. board visually.

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.

The unit doesn’t operate with the remote controller.

Also, the Operation Indicator lamp doesn’t light up by pressing the EMERGENCY OPERATION switch.

Yes

No

Replace the vane motor.

Yes

Is winding resistance of vane motor 0 " ?

No

Be sure to check both fresistance.

Is winding resistance of fan motor 0 " ?

No

Yes

Replace the fan motor .

Replace the fuse.

Yes

Is fuse(F11) blown?

No

Be sure to check both fuse and varistor in any case.

Is varistor(NR11) burnt?

Yes

No

Replace the varistor.

1

3

CN201

1

2

F12

L

N

Terminal block

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.

Trouble of the indoor electronic control P.C. board.

Yes

Is resistance 0 " ?

No

Trouble of fuse (F12)

D Check of outdoor unit

Compressor and outdoor fan do not operate.(Only indoor fan operates.)

Start

Press the EMERGENCY

OPERATION switch.

3-minute time delay works.

Test run operation operates for 30 minutes.

Yes

Check the outdoor wiring, the outdoor fan motor and compressor.

Yes

Check the continuity of indoor and outdoor unit

Check the voltage to terminal block of outdoor unit.

Is there 220-240V AC to terminal block between 2 - N ?

No

Check the voltage to terminal block of indoor unit.

Is there 220-240V AC to terminal block between

2

-

N

?

No

Replace the indoor electronic control P.C. board.

22

TEST POINT DIAGRAM AND VOLTAGE

MS-18NV -

E4

Indoor electronic control P.C. board

}

Fan motor power supply

Fuse 250V AC 3.15A

}

Power supply input

220-240V AC

+

--

C144

C144

}

5V DC

Room temperature thermistor(RT11)

Indoor coil thermistor(RT12)

Timer short mode point

Emergency operation switch

--

+

JPG

JP45

}

12V DC

Room temperature thermistor (RT11)

Indoor coil thermistor (RT12)

Auto restart function

Cut the Resistor JR06.

(Refer page 17.)

23

11 DISASSEMBLY INSTRUCTIONS

<"Terminal with lock mechanism" Detaching points>

In case of a terminal with lock mechanism, detach the terminal as shown below.

(1) (2)

1 Slide the sleeve.

2 Pull the terminal while

pushing the locking

lever.

1 Hold the sleeve, and

pull out the terminal

slowly.

11-1. MS-18NV -

E4

INDOOR UNIT

OPERATING PROCEDURE

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.

Photo 1

PHOTOS

Front panel

Screws

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.

Photo 2

Ground Indoor coil thermistor

Screws

Terminal block screw

Indoor electronic control

P.C. board

24

OPERATING PROCEDURE

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.

Photo 3

PHOTOS screw

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 4

Catch

Heat exchanger screw

Bearing support screws

Photo 5 screw

Heat exchanger

Indoor fan motor

Fan motor screws

Line flow fan

Screws of motor band

25

11-2. MU-18NV -

E4

OUTDOOR UNIT

OPERATING PROCEDURE

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.

Photo 1

PHOTOS

Screws

Service panel

Photo 2

Screws

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

Photo 3

26

Compressor capacitor

OPERATING PROCEDURE

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.

Photo 4

PHOTOS

Hook

Connector

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.

Propeller fan

Propeller fan nut

Soundproof felt

Photo 5

Discharge pipe

Suction pipe

Compressor

Compressor set nuts

27

1

2

12 PARTS LIST

MS-18NV -

E4

(WH)

12-1. INDOOR UNIT

STRUCTURAL PARTS

5

3

Optional parts

(See page 31.)

12-2. INDOOR UNIT

HEAT EXCHANGER

8

6

SCREW CAP

9 10

4

12-1. INDOOR UNIT STRUCTURAL PARTS

Part number that is circled is not shown in the illustration.

NO.

Part No.

Part Name

Symbol in Wiring

Diagram

5

6

7

3

4

1

2

E02 138 000

E02 138 010

E02 143 234

E02 141 100

E02 141 970

E02 143 067

E02 171 007

FRONT PANEL (WH)

GRILLE (WH)

BOX (WH)

AIR FILTER

INSTALLATION PLATE

SCREW CAP (WH)

LAMP PANEL (WH)

12-2. INDOOR UNIT HEAT EXCHANGER

8

9

10

E02 141 620

E02 138 667

E02 138 666

INDOOR HEAT EXCHANGER

UNION(LIQUID)

UNION(GAS)

Q'ty/unit

MS-18NV- E4

(WH)

1

2

1

1

1

3

1

Remarks

3PCS/SET

1

1

1

{ 6.35

{ 15.88

28

3

1

2

MS-18NV -

E4

(WH)

12-3. INDOOR UNIT

FUNCTIONAL PARTS

AND ELECTRICAL PARTS

8

15

SLEEVE

BEARING

10

11

5

4

16

14

INDOOR COIL

THERMISTOR

9 6 12 17 ROOM TEMPERATURE

THERMISTOR

7

12-4. ACCESSORY PARTS

AND REMOTE CONTROLLER

21 22

12-3. INDOOR UNIT FUNCTIONAL PARTS AND ELECTRICAL PARTS

Part number that are circled are not shown in the illustration.

NO.

Part No.

Part Name

13

14

15

16

9

10

11

12

17

18

19

20

1

6

7

8

4

5

2

3

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

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 THERMISTOR

FUSE

THERMAL FUSE

SURGE ABSORBER

Symbol in Wiring

Diagram

MF

MV

TB

NR11

RT12

RT11

F11

F12

DSAR

Q'ty/unit

MS-18NV- E4

(WH)

1

1

1

1

1

1

1

2

1

1

1

1

1

1

1

1

1

1

1

1

12-4. ACCESSORY PARTS AND REMOTE CONTROLLER

21

22

E02 138 426

E02 141 083

REMOTE CONTROLLER

REMOTE CONTROLLER HOLDER

29

1

1

Remarks

RA4V27 -

2PCS/SET

AUTO RESTART

3.15A

93 :

MU-18NV -

E4

12-5. OUTDOOR UNIT

STRUCTURAL PARTS

17

1

2

10

9 5

Part number that are circled are not shown in the illustration.

NO.

Part No.

Part Name

Symbol in Wiring

Diagram

11

12

13

14

7

8

9

10

15

16

17

18

3

4

1

2

5

6

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

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

MC

MF

C1

C2

TB

F

30

14

6

Q'ty/unit

MU-18NV-

E4

1

1

1

1

1

1

1

1

1

1

1

1

1

1

1

4

1

1

7

Remarks

PH-33VPET

RA6V50 -

50 + /440V

3.0

+ /440V

{ 3.0

o{ 2.0

o 700

4RUBBERS/SET

{ 6.35

{ 15.88

250V/2A

3

15

16

11

12

4

8

13 OPTIONAL PARTS

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.

Model

MS-18NV E4

Part No.

MAC-1100FT

Air cleaning filter (White bellows type)

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.

Model

MS-18NV -

E4

Part No.

MAC-1600DF

Deodorizing filter (Gray sponge type)

● DEODORIZING FILTER and AIR CLEANING FILTER can be attached on either side.

31

HEAD OFFICE MITSUBISHI DENKI BLDG.MARUNOUCHI TOKYO100-8310 TELEX J24532 CABLE MELCO TOKYO

C 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.