Hitachi RAI-50NH5, RAC-50NH5 Service Manual

SERVICE MANUAL

TECHNICAL INFORMATION

PM

NO. 0274E

RAI-50NH5/RAC-50NH5

REFER TO THE FOUNDATION MANUAL

FOR SERVICE PERSONNEL ONLY

RAI-ECPM

RAI-50NH5

RAC-50NH5

CONTENTS

SPECIFICATIONS ------------------------------------------------------------------- 4

HOW TO USE ------------------------------------------------------------------------ 6

CONSTRUCTION AND DIMENSIONAL DIAGRAM ---------------------- 27

MAIN PARTS COMPONENT --------------------------------------------------- 29

WIRING DIAGRAM ----------------------------------------------------------------- 31

CIRCUIT DIAGRAM ---------------------------------------------------------------- 33

PRINTED WIRING BOARD LOCATION DIAGRAM ---------------------- 39

BLOCK DIAGRAM ------------------------------------------------------------------ 41

BASIC MODE ------------------------------------------------------------------------ 43

REFRIGERATING CYCLE DIAGRAM ---------------------------------------- 57

AUTO SWING FUNCTION ------------------------------------------------------- 58

DESCRIPTION OF MAIN CIRCUIT OPERATION ------------------------ 59

SERVICE CALL Q & A ----------------------------------------------------------- 90

TROUBLE SHOOTING ------------------------------------------------------------ 93

PARTS LIST AND DIAGRAM ------------------------------------------------- 113

SPECIFICATIONS

TYPE

MODEL

POWER SOURCE

TOTAL INPUT

COOLING

HEATING

DIMENSIONS (mm)

NET WEIGHT

TOTAL AMPERES

CAPACITY

TOTAL INPUT

TOTAL AMPERES

CAPACITY

(W)

(A)

(kW)

(B.T.U./h)

(W)

(A)

(kW)

(B.T.U./h)

W

H

D

(kg)

DC INVERTER (CEILING CASSETTE TYPE)

INDOOR UNIT

RAI-50NH5

1 PHASE, 50 Hz, 220-240V

1,990 (155~2,200)

9.10 ~ 8.37

5.00 (0.90 ~ 5.20)

17,070

2,160 (155 ~ 2,200)

9.87 ~ 9.05

6.50 (0.90 ~ 8.10)

22,190

580

285

580

20

OUTDOOR UNIT

RAC-50NH5

SPECIFICATIONS AND PARTS ARE SUBJECT TO CHANGE FOR IMPROVEMENT

850

650

298

60

DECEMBER 2005

0274E cover(RAI-50NH5) 19/10/05, 2:41 PM1

ROOM AIR CONDITIONER

INDOOR UNIT + OUTDOOR UNIT

Refrigeration & Air-Conditioning Division

SAFETY DURING REPAIR WORK

1. In order to disassemble and repair the unit in question, be sure to disconnect the power cord plug from the power outlet before starting the work.

2. If it is necessary to replace any parts, they should be replaced with respective genuine parts for the unit, and the replacement must be effected in correct manner according to the instructions in the Service Manual of the unit.

If the contacts of electrical parts are defective, replace the electrical parts without trying to repair them.

First, I must disconnect the power cord plug

from the power outlet.

3. After completion of repairs, the initial state should be restored.

4. Lead wires should be connected and laid as in the initial state.

5. Modification of the unit by user himself should absolutely be prohibited.

6. Tools and measuring instruments for use in repairs or inspection should be accurately calibrated in advance.

7. In installing the unit having been repaired, be careful to prevent the occurence of any accident such as electrical shock, leak of current, or bodily injury due to the drop of any part.

8. To check the insulation of the unit, measure the insulation resistance between the power cord plug and grounding terminal of the unit. The insulation resistance should be 1M DC megger.

9. The initial location of installation such as window, floor or the other should be checked for being and safe enough to support the repaired unit again. If it is found not so strong and safe, the unit should be installed at the initial location reinforced or at a new location.

10. Any inflammable thing should never be placed about the location of installation.

or more as measured by a 500V

DANGER

11. Check the grounding to see whether it is proper or not, and if it is found improper, connect the grounding terminal to the earth.

0274E Pg 1-5(RAI-50NH5) 19/10/05, 2:44 PM1

– i –

WORKING STANDARDS FOR PREVENTING BREAKAGE OF SEMICONDUCTORS

1. Scope The standards provide for items to be generally observed in carrying and handling semiconductors in relative manufacturers during maintenance and handling thereof. (They apply the same to handling of abnormal goods such as rejected goods being returned).

2. Object parts

(1) Micro computer (2) Integrated circuits (IC) (3) Field-effect transistors (FET) (4) P.C. boards or the like on which the parts mentioned in (1) and (2) of this paragraph are equipped.

3. Items to be observed in handling

(1) Use a conductive container for carrying and storing of parts. (Even rejected goods should be handled in

the same way).

A conductive polyvinyl bag

IC

Conductive sponge

IC

Fig. 1. Conductive Container

(2) When any part is handled uncovered (in counting, packing and the like), the handling person must always

use himself as a body earth. (Make yourself a body earth by passing one M ohm earth resistance through a ring or bracelet).

(3) Be careful not to touch the parts with your clothing when you hold a part even if a body earth is being

taken.

(4) Be sure to place a part on a metal plate with grounding.

(5) Be careful not to fail to turn off power when you repair the printed circuit board. At the same time, try

to repair the printed circuit board on a grounded metal plate.

0274E Pg 1-5(RAI-50NH5) 19/10/05, 2:44 PM2

Body earth (Elimik conductive band)

1M

Fig. 2. Body Earth

Clip for connection with a grounding wire

– 1 –

(6) Use a three wire type soldering iron including a grounding wire.

Metal plate (of aluminium, stainless steel, etc.)

Working table

Bare copper wire (for body earth)

Staple

Fig. 3. Grounding of the working table

Soldering iron

2

Resistor of 1 M

Earth wire

Grounding wire

(1/2W)

Screw stop at the screwed part using a rag plate

Fig. 4. Grounding a soldering iron

Use a high insulation mode (100V, 10M

or higher) when ordinary iron is to be used.

(7) In checking circuits for maintenance, inspection or some others, be careful not to have the test probes of the

measuring instrument shortcircuit a load circuit or the like.

– 2 –

0274E Pg 1-5(RAI-50NH5) 19/10/05, 2:44 PM3

CAUTION

!

1. In quiet operation or stopping the running, slight flowing noise of refrigerant in the refrigerating cycle is

heard occasionally, but this noise is not abnormal for the operation.

2. When it thunders near by, it is recommend to stop the operation and to disconnect the power cord plug

from the power outlet for safety.

3. The room air conditioner does not start automatically after recovery of the electric power failure for

preventing fuse blowing. Re-press START/STOP button after 3 minutes from when unit stopped.

4. If the room air conditioner is stopped by adjusting thermostat, or missoperation, and re-start in a moment,

there is occasion that the cooling and heating operation does not start for 3 minutes, it is not abnormal and this is the result of the operation of IC delay circuit. This IC delay circuit ensures that there is no danger of blowing fuse or damaging parts even if operation is restarted accidentally.

5. This room air conditioner should not be used at the cooling operation when the outside temperature is

below –10°C (14°F).

6. This room air conditioner (the reverse cycle) should not be used when the outside temperature is below

–15°C (5°F). If the reverse cycle is used under this condition, the outside heat exchanger is frosted and efficiency falls.

7. When the outside heat exchanger is frosted, the frost is melted by operating the hot gas system, it is not

trouble that at this time fan stops and the vapour may rise from the outside heat exchanger.

0274E Pg 1-5(RAI-50NH5) 19/10/05, 2:44 PM4

– 3 –

SPECIFICATIONS

MODEL

FAN MOTOR

FAN MOTOR CAPACITOR

FAN MOTOR PROTECTOR

COMPRESSOR

COMPRESSOR MOTOR CAPACITOR

OVERLOAD PROTECTOR

OVERHEAT PROTECTOR

FUSE (for MICROPROCESSOR)

POWER RELAY

POWER SWITCH

RAI-50NH5

25W

NO

–

NO

RAC-50NH5

40 W

NO

JU1013D

NO

YES

3.0A

G4A

NO

TEMPORARY SWITCH

SERVICE SWITCH

TRANSFORMER

VARISTOR

NOISE SUPPRESSOR

THERMOSTAT

REMOTE CONTROL SWITCH (LIQUID CRYSTAL)

REFRIGERANT CHARGING

UNIT

VOLUME (Refrigerant 410A)

PIPES (MAX. 20m)

YES

NO

YES(IC)

YES

----------

NO

YES

NO

450NR

YES

YES(IC)

NO

1400g

WITHOUT REFRIGERANT BECAUSE

COUPLING IS FLARE TYPE.

0274E Pg 1-5(RAI-50NH5) 19/10/05, 2:44 PM5

– 4 –

Figure showing the Installation of Indoor and Outdoor unit.

!

CAUTION

The installation height of indoor unit must be 2.3m or more.

Be sure to completely seal any gap with putty.

Maximum pipe length 20m

Minimum pipe length 5m

above 200mm

above 50mm when installed on the

(

ceiling of balcony

)

above 100mm

give clearance as wide as possible

The indoor piping should be insulated with the enclosed insulation pipe. (If the insulator is insufficient, please use commersial products)

● The difference in height

between the indoor and outdoor unit should be kept below 5m.

● The connecting pipe, no

matter big or small, should all be insulated with insulation pipe and then wrapped with vinyl tape. (The insulator will deteriorate if it is not wrapped with tape).

Drain Pipe Must be installed separately. Insulate indoor part of pipe to prevent condensation.

above 100mm

above 700mm

0274E Pg 1-5(RAI-50NH5) 19/10/05, 2:44 PM6

above 200mm

– 5 –

SAFETY PRECAUTION

●

Please read the “Safety Precaution” carefully before operating the unit to ensure correct usage of the unit.

●

Pay special attention to signs of “ Warning” and “ Caution”. The “Warning” section contains matters which, if not observed strictly, may cause death or serious injury. The “Caution” section contains matters which may result in serious consequences if not observed properly. Please observe all instructions strictly to ensure safety.

●

The sign indicate the following meanings.

!

Make sure to connect earth line.

Indicates the instructions that must be followed.

●

Please keep this manual after reading.

PRECAUTIONS DURING INSTALLATION

●

Do not reconstruct the unit. Water leakage, fault, short circuit or fire may occur if you reconstruct the unit by yourself.

●

!

WARNING

!

CAUTION

Please ask your sales agent or qualified technician for the installation of your unit. Water leakage, short circuit or fire may occur if you install the unit by yourself.

●

Please use earth line. Do not place the earth line near water or gas pipes, lightning-conductor, or

the earth line of telephone. Improper installation of earth line may cause electric shock.

●

A circuit breaker should be installed depending on the mounting site of the unit. Without a circuit breaker, the danger of electric shock exists.

●

Do not install near location where there is flammable gas. The outdoor unit may catch fire if flammable gas leaks around it.

●

Please ensure smooth flow of water when installing the drain hose.

The sign in the figure indicates prohibition.

W

A R N

N G

!

W

A R N

N

G

PRECAUTIONS DURING SHIFTING OR MAINTENANCE

●

Should abnormal situation arises (like burning smell), please stop operating the unit

!

I

and turn off the circuit breaker. Contact your agent. Fault, short circuit or fire may occur if you continue to operate the unit under abnormal situation.

●

Please contact your agent for maintenance. Improper self maintenance may cause electric shock and fire.

●

Please contact your agent if you need to remove and reinstall the unit. Electric shock or fire may occur if you remove and reinstall the unit yourself improperly.

PRECAUTIONS DURING OPERATION

●

Avoid an extended period of direct air flow for your health.

●

Do not insert a finger, a rod or other objects into the air outlet or inlet. As the fan is rotating at a high speed, it will cause injury. Before cleaning, be sure to stop the operation and turn the breaker OFF.

●

I

Do not use any conductor as fuse wire, this could cause fatal accident.

●

During thunder storm, disconnect and turn off the circuit breaker.

0274E Pg 6-18(RAI-50NH5) 19/10/05, 2:46 PM6

– 6 –

PRECAUTIONS DURING OPERATION

●

The product shall be operated under the manufacturer specification and not for any other intended use.

●

Do not attempt to operate the unit with wet hands, this could cause fatal accident.

●

When operating the unit with burning equipments, regularly ventilate the room to avoid oxygen insufficiency.

●

Do not direct the cool air coming out from the air-conditioner panel to face household heating apparatus as this may affect the working of apparatus such as the electric kettle, oven etc.

●

Please ensure that outdoor mounting frame is always stable, firm and without defect. If not, the outdoor unit may collapse and cause danger.

●

Do not splash or direct water to the body of the unit when cleaning it as this

!

may cause short circuit.

C A U T

I

●

Do not use any aerosol or hair sprays near the indoor unit. This chemical can adhere on heat exchanger fin and blocked the evaporation water flow to drain pan. The water will drop on tangential fan and cause water splashing out from indoor unit.

O N

●

Please switch off the unit and turn off the circuit breaker during cleaning, the high-speed fan inside the unit may cause danger.

●

Turn off the circuit breaker if the unit is not to be operated for a long period.

●

Do not climb on the outdoor unit or put objects on it.

●

When operating the unit with the door and windows opened, (the room humidity is always above 80%) and with the air deflector facing down or moving automatically for a long period of time, water will condense on the air deflector and drips down occasionally. This will wet your furniture. Therefore, do not operate under such condition for a long time.

●

If the amount of heat in the room is above the cooling or heating capability of the unit (for example: more people entering the room, using heating equipments and etc.), the preset room temperature cannot be achieved.

●

This appliance is not intended for use by young children or infirm persons unless they have been adequately supervised by a responsible person to ensure that they can use the appliance safely.

●

Young children should be supervised to ensure that they do not play with the appliance.

0274E Pg 6-18(RAI-50NH5) 19/10/05, 2:46 PM7

– 7 –

NAMES AND FUNCTIONS OF EACH PART

INDOOR UNIT

AIR FILTER

To prevent dust from coming into the indoor unit. (Refer page 19)

INDOOR UNIT INDICATORS

Light indicator showing the operating condition. (Refer page 5)

SUCTION GRILL (AIR INLET)

HORIZONTAL DEFLECTOR (AIR OUTLET)

(Refer page 15)

REMOTE CONTROL

Send out operation signal to the indoor unit. So as to operate the whole unit. (Refer page 6)

MODEL NAME AND DIMENSIONS

MODEL

RAI-50NH5

WIDTH (mm)

580

HEIGHT (mm)

285

DEPTH (mm)

580

MULTI-AIR CONDITIONER

With this multi-air conditioner, several indoor units can be connected to one outdoor unit to be driven. You can operate the required number of indoor units.

Combination of Operations:

When operation mode is selected:

● You cannot operate the indoor units in the

following combinations.

One unit

Heating

During automatic operation:

● When heating operation is automatically selected for the first indoor unit, the next indoor unit will then start to heat.

Also, if cooling or dehumidifying is automatically selected for the first indoor unit, the next indoor unit will also start to cool or dehumidify.

Other unit

Cooling

Dehumidifying

Circulating (fan)

● The indoor unit which is switched on first continues to

operate, but other indoor units which is switched on later does not operate while the lamp lights.

● To re-start an indoor unit which was operated later, stop

the indoor unit which was operated first or later and reset the type of operation, then perform operation again.

Adjusting the Number of Indoor Units:

Decrease the number of indoor units to be operated especially when it is very hot or cold or when you want to reach the present temperature quickly.

0274E Pg 6-18(RAI-50NH5) 19/10/05, 2:46 PM8

Stopped Indoor Units:

When an indoor unit is operated in the cooling, heating or dehumidifying mode in the room, the sound of refrigerant flow may be heard from a stopped indoor unit or a stopped indoor unit may become warm. This is because the indoor unit returns refrigerant to the outdoor unit to be ready for operation.

– 8 –

OPERATION INDICATOR

TEMPORARY SWITCH

TEMPORARY

SWITCH

Use this switch to start and stop when the remote controller does not work.

[Use non-conductor stick (example toothpick)]

● By pressing the temporary switch, the operation is done in previously set

operation mode.

● When the operation is done using the temporary switch after the power

source is turned off and turn on again, the operation will be done in automatic mode.

INDOOR UNIT INDICATORS

OPERATION LAMP

This lamp lights during operation. The OPERATION LAMP flashes in the following cases during heating.

(1) During preheating

For about 2–3 minutes after starting up.

(2) During defrosting

Defrosting will be performed about once an hour when frost forms on the heat exchanger of the outdoor unit, for 5–10 minutes each time.

Press

Nonconducted stick

Temporary Switch

about 5.5mm

0274E Pg 6-18(RAI-50NH5) 19/10/05, 2:46 PM9

TIMER LAMP

This lamp lights when the timer is working.

FILTER LAMP

When the device is operated for a total of about 200 hours, the FILTER lamp lights to indicate that it is time to clean the filter. The lamp goes out when the “ (AUTO SWING)” button is pressed while the device is on “STANDBY MODE”.

– 9 –

NAMES AND FUNCTIONS OF REMOTE CONTROL UNIT

REMOTE CONTROLLER

● Operate by pointing towards the signal receptor on the indoor unit. The range of control is

about 7 meters. Signal receivable angle range is approximately 70°. However, if there is an electronic light sensor device (inverter) in the room, signal may not be received or receivable distance may become shorter.

● Indoor unit must be install 1 meter or more away from lighting.

● Handle the remote controller with care. Dropping it or getting it wet may compromise its

signal transmission capability.

● After new batteries are inserted into the remote controller, the unit will initially require approximately 10 seconds to respond to commands and operate.

● Signal emitting window/transmission sign

Point this window toward the indoor unit when controlling it.

CH

˚

CH

˚

RESET

AUTO

HEAT

DEHUMIDIFY

COOL

FAN

FAN SPEED LOW MED HI

SLEEPING

STOP (CANCEL)

START (RESERVE)

START/STOP

TIME

TIMER SET

TIMER SELECTOR ON TIMER OFF TIMER

AUTO SWING

The transmission sign blinks when a signal is sent.

● Display

This indicates the room temperature selected, current time, timer status, function and intensity of circulation selected.

● START/STOP button

Press this button to start operation. Press it again to stop operation.

● SLEEP button

Use this button to set the sleep timer.

● TEMPERATURE buttons

Use these buttons to raise or lower the temperature setting. (Keep pressed, and the value will change more quickly.)

● TIME button

Use this button to set and check the time and date.

● RESET buttons

● FUNCTION selector

Use this button to select the operating mode. Every time you press it, the mode will change from (AUTO) to (HEAT) to (DEHUMIDIFY) to

(COOL) and to (FAN) cyclically.

● FAN SPEED selector

This determines the fan speed. Every time you press this button, the intensity of circulation will change from (AUTO) to (HI) to (MED) to (LOW) (This button allows selecting the optimal or preferred fan speed for each operation mode).

● AUTO SWING button

Controls the angle of the horizontal air deflector.

● TIMER control

Use this button to set the timer.

● OFF-TIMER button Select the turn OFF time.

● ON-TIMER button Select the turn ON time.

● RESERVE button Time setting reservation.

● CANCEL button Cancel time reservation.

Precautions for Use

● Do not put the remote controller in the following places.

● Under direct sunlight.

● In the vicinity of a heater.

● Handle the remote controller carefully. Do not drop it on the floor,

and protect it from water.

● Once the outdoor unit stops, it will not restart for about 3 minutes

(unless you turn the power switch off and on or unplug the power cord and plug it in again).

This is to protect the device and does not indicate a failure.

● If you press the FUNCTION selector button during operation, the

device may stop for about 3 minutes for protection.

▲

Approximately 70°

0274E Pg 6-18(RAI-50NH5) 19/10/05, 2:46 PM10

– 10 –

VARIOUS FUNCTIONS

■ Auto Restart Control

● If there is a power failure, operation will be automatically restarted when the power is resumed with previous operation mode

and airflow direction. (As the operation is not stopped by remote controller.)

● If you intend not to continue the operation when the power is resumed, switch off the power supply.

When you switch on the circuit breaker, the operation will be automatically restarted with previous operation mode and airflow direction. Note: 1. If you do not require Auto Restart Control, please consult your sales agent or OFF by remote control.

2. Auto Restart Control is not available when Timer or Sleep Timer mode is set.

AUTOMATIC OPERATION

The device will automatically determine the mode of operation, HEAT, COOL or DEHUMIDIFY depending on the current room temperature. The selected mode of operation will change when the room temperature varies. However the mode of operation will not change when indoor unit connected to multi type outdoor unit.

Press the FUNCTION selector so that the display indicates the (AUTO) mode of operation.

● When AUTO has been selected, the device will automatically determine the mode of operation, HEAT, COOL or DEHUMIDIFY depending on the current room temperature.

1

However the mode of operation will not change when indoor unit connected to multi type outdoor unit.

● If the mode automatically selected by the unit is not satisfactory, manually change the mode setting (heat, dehumidify, cool or fan).

RESET

START

STOP

■ As the settings are stored in memory in the remote controller, you only have to press the

Press the (START/STOP) button. Operation starts with a beep. Press the button again to stop operation.

(START/STOP) button next time.

You can raise or lower the temperature setting as necessary by maximum of 3°C.

°C

● The preset temperature and the actual room temperature may vary somewhat depending on conditions.

● The display does not indicate the preset temperature in the AUTO mode. If you change the setting, the indoor unit will produce a beep.

Press the (FAN SPEED) button, AUTO and LOW is available.

Press the temperature button and the temperature setting will change by 1°C each time.

0274E Pg 6-18(RAI-50NH5) 19/10/05, 2:46 PM11

– 11 –

HEATING OPERATION

● Use the device for heating when the outdoor temperature is under 21°C.

When it is too warm (over 21°C), the heating function may not work in order to protect the device.

● In order to keep reliability of the device, please use this device above -15°C of the outdoor temperature.

Press the FUNCTION selector so that the display indicates (HEAT).

Set the desired FAN SPEED with the (FAN SPEED) button (the display indicates the setting).

(AUTO): The fan speed is HI at first and varies to MED

or LOW automatically when the preset temperature has been reached.

(HI) : Economical as the room will become warm

quickly. But you may feel a chill at the beginning.

(MED) : Fan speed slow.

(LOW) : Fan speed slower.

RESET

C

˚

1

2

Set the desired room temperature with the TEMPERATURE buttons (the display indicates the setting).

3

C

˚

START

STOP

■ As the settings are stored in memory in the remote controller, you only

The temperature setting and the actual room temperature may vary somewhat depending on conditions.

Press the (START/STOP) button. Heating operation starts with a beep. Press the button again to stop operation.

have to press the (START/STOP) button next time.

0274E Pg 6-18(RAI-50NH5) 15/11/05, 9:30 AM12

– 12 –

DEHUMIDIFYING OPERATION

Use the device for dehumidifying when the room temperature is over 16°C. When it is under 15°C, the dehumidifying function will not work.

Press the FUNCTION selector so that the display indicates

(DEHUMIDIFY). The FAN SPEED is set at LOW automatically. The FAN SPEED button does not work.

Set the desired room temperature with the TEMPERATURE button (the display indicates the setting).

The range of 20-26˚C is recommended as the room temperature for dehumidifying.

RESET

C

˚

1

2

C

˚

■ Dehumidifying Function

START

STOP

■ As the settings are stored in memory in the remote controller, you

Press the (START/STOP) button. Dehumidifying operation starts with a beep. Press the button again to stop operation.

only have to press the

(START/STOP) button next time.

When the room temperature is higher than the temperature setting: The device will dehumidify the room, reducing the room temperature to the preset level. When the room temperature is lower than the temperature setting: Dehumidifying will be performed at the temperature setting slightly lower than the current room temperature, regardless of the temperature setting. The function will stop (the indoor unit will stop emitting air) as soon as the room temperature becomes lower than the setting temperature.

0274E Pg 6-18(RAI-50NH5) 19/10/05, 2:46 PM13

– 13 –

COOLING OPERATION

Use the device for cooling when the outdoor temperature is 22-42°C. If in doors humidity is very high (80%), some dew may form on the air outlet grille of the indoor unit.

Press the FUNCTION selector so that the display indicates

C

˚

1

(COOL).

RESET

Set the desired FAN SPEED with the (the display indicates the setting).

(AUTO): The FAN SPEED is HI at first and varies to

MED or LOW automatically when the preset

2

(HI) : Economical as the room will become cool

(MED) : Fan speed slow.

(LOW) : Fan speed slower.

Set the desired room temperature with the TEMPERATURE button (the display indicates the setting).

3

C

˚

START

STOP

The temperature setting and the actual room temperature may vary some how depending on conditions.

Press the with a beep. Press the button again to stop operation. The cooling function does not start if the temperature setting is

higher than the current room temperature (even though the (OPERATION) lamp lights). The cooling function will start as soon as you set the temperature below the current room temperature.

temperature has been reached.

quickly.

(START/STOP) button. Cooling operation starts

(FAN SPEED) button

■ As the settings are stored in memory in the remote controller, you

only have to press the

(START/STOP) button next time.

0274E Pg 6-18(RAI-50NH5) 15/11/05, 9:30 AM14

– 14 –

FAN OPERATION

You can use the device simply as an air circulator. Use this function to dry the interior of the indoor unit at the end of summer.

Press the FUNCTION selector so that the display indicates

1

(FAN).

RESET

FAN SPEED (AUTO)

For the heating operation

2

START

STOP

.....

When the AUTO fan speed mode is set in the cooling/heating operation:

● The fan speed will automatically change according to the temperature

of discharged air.

● When the difference of room temperature and setting temperature is

large, fan starts to run at HI speed.

● When the room temperature reaches setting temperature, fan speed

changes to LOW automatically.

Press the (FAN SPEED) button.

Press the (START/STOP) button. Fan operation starts with a beep. Press the button again to stop operation.

For the cooling operation

● When the difference of room temperature and setting temperature is

large, fan starts to run at HI speed.

● After room temperature reaches the preset temperature, the cooling

operation, which changes the fan speed and room temperature to obtain optimum conditions for natural healthful cooling will be performed.

– 15 –

0274E Pg 6-18(RAI-50NH5) 19/10/05, 2:47 PM15

HOW TO SET THE TIMER

RESET

Time, Day, Month

TIME, DAY, MONTH

After you change the batteries;

(current time, day, month)

OFF TIMER

ON TIMER

OFF-Timer

RESERVE

CANCEL

You can set the device to turn off at the present time.

ON-Timer

● The device will turn on

at the designated times.

Start

M D

STOP

Stop

Start

1

Set the current month and

day with the TIMER control button.

M D

1

Press the (OFF-TIMER)

button. The (OFF) mark blinks on the display.

AM

1

Press the (ON-TIMER)

button the (ON) mark blinks on the display.

AM

3

ON/OFF-Timer

Start Stop

● The device will turn on (off) and off (on) at the designated times.

● The switching occurs first at the preset time that comes earlier.

● The arrow mark appearing on the display indicates the sequence of switching operations.

1

Press the (ON-OFF)

button so that the (OFF) mark blinks.

PM

2

Set the turn-off time

with the TIMER control button. Press the (RESERVE) button.

PM

Press the (ON-

TIMER) button so that the (OFF) mark lights and the (ON) mark blinks.

PM

AM

How to Cancel Reservation

Point the signal window of the remote controller toward the indoor unit, and press the (CANCEL) button. The (RESERVED) sign goes out with a beep and the (TIMER) lamp turns off on the indoor unit.

NOTE

You can set only one of the OFF-timer, ON-timer and ON/OFF-timer.

0274E Pg 6-18(RAI-50NH5) 19/10/05, 2:47 PM16

– 16 –

2

Press the

(TIME) button.

AM PM PM

2

Set the turn-off time with the

TIMER control button.

3

TIMER control button.

PM

Set the current time with the

Example: The current time is 1:30 p.m.

3

Point the signal window of the remote controller toward the indoor unit, and

press the (RESERVE) button. The (OFF) mark starts lighting instead of flashing and the sign (RESERVED) lights. A beep occurs and the (TIMER) lamp lights on the indoor unit.

4

Press the (TIME) button again.

The time indication starts lighting instead of flashing.

● The time indication will disappear

PM

● To check the current time setting,

automatically in 10 second.

press the (TIME) button twice.

The setting of the current time is now complete.

2

Set the turn-on time with the

TIMER control button.

AM

4

Set the turn-on time with the

TIMER control button.

PM

AM

PM

The setting of turn-off time is now complete.

3

Point the signal window of the remote controller toward the indoor unit, and

press the (RESERVE) button. The (ON) mark starts lighting instead of flashing and the (RESERVED) sign lights. A beep occurs and the (TIMER) lamp lights on the indoor unit.

Example:

AM

5

Point the signal window of the remote controller toward the indoor unit, and

press the (RESERVE) button. The (ON) mark starts lighting instead of flashing and the (RESERVED) sign lights. A beep occurs and the (TIMER) lamp lights on the indoor unit.

PM

AM

The device will turn on at 7:00 a.m. The setting of the turn-on time is now complete.

Example: The device will turn off at 10:30 p.m. and it will be turned on at 7:00 a.m. The settings of the turn-on/off times are now complete.

Example: The device will turn off at 11:00p.m.

● The timer may be used in three ways: off-timer, on-timer, and ON/OFF (OFF/ON)-timer. Set

the current time at first because it serves as a reference.

● As the time settings are stored in memory in the remote controller, you only have to press

the (RESERVE) button in order to use the same settings next time.

0274E Pg 6-18(RAI-50NH5) 19/10/05, 2:47 PM17

– 17 –

HOW TO SET THE SLEEP TIMER

Set the current time at first if it is not set before (see the pages for setting the current time). Press the (SLEEP) button, and the display changes as shown below.

Mode

44 44

H

SLEEP

Sleep timer

Sleep Timer: The device will continue working for the designated number of hours and then turn off. Point the signal window of the remote controller toward the indoor unit, and press the SLEEP button. The timer information will be displayed on the remote controller. The TIMER lamp lights with a beep from the indoor unit. When the sleep timer has been set, the display indicates the turn-off time.

H

Sleep

timer

1

Set the ON-timer.

Start

1 hour 2 hours 3 hours 7 hours

The device will be turned off by the sleep timer and turned on by on-timer.

Indication

Sleep timer off

Example: If you set 3 hours sleep time at 11:38 p.m., the turn-off time is 2:38 a.m.

1

2

Press the (SLEEP) button and set the sleep timer.

AM

H

AM

For heating:

In this case, the device will turn off in 2 hours (at 1:38 a.m.) and turn on early so that the preset temperature will be almost reached at 6:00 next morning.

How to Cancel Reservation

Point the signal window of the remote controller toward the indoor unit, and press the (CANCEL) button. The (RESERVED) sign goes out with a beep and the (TIMER) lamp turns off on the indoor unit.

0274E Pg 6-18(RAI-50NH5) 19/10/05, 2:47 PM18

– 18 –

ADJUSTING THE AIR DEFLECTOR

about 45˚

SWINGING

RANGE

45˚

about 45˚

SWINGING RANGE

45˚

Adjustment of the conditioned air in the upward and

1

downward directions.

According to “Dehumidifying” or “Cooling” operation, the horizontal air deflector is automatically set to the proper angle suitable for each operation. The deflector can be swung up and down and also set to the desired angle using the “ (AUTO SWING)” button. (If the angle of the deflector is changed, it will not return to the autoset position after operations start unless the operation mode is switched.)

● If the “ (AUTO SWING)” button is pressed

once, the horizontal air deflector swings up and down. If the button is pressed again, the deflector stops in its current position. Several seconds (about 6 seconds) may be required before the deflector starts to move.

● Use the horizontal air deflector within the adjusting

range shown on the right.

RESET

ENGLISH

● When the “ (AUTO SWING)” button is

pressed while the operation is stopped, the horizontal air deflector moves and stops at the position where the air outlet closes.

● When the auto swing operation is performed, if the

horizontal air deflector is moved manually, the swinging range may drift. However, it will return to the original operation range after a short time.

CAUTION

!

When operating the unit in cooling operation with the air deflector facing down and moving automatically for a long period of time, water will condensed on the air deflector and drips down occasionally. This will wet your furniture.

0274E Pg 19-26(RAI-50NH5) 19/10/05, 2:51 PM19

– 19 –

HOW TO EXCHANGE THE BATTERIES IN THE REMOTE CONTROLLER

Remove the cover as shown in the figure and take out the

1

old batteries.

=

Install the new batteries.

2

The direction of the batteries should match the marks in the case.

!

CAUTION

1. Do not use new and old batteries, or different kinds of batteries together.

2. Take out the batteries when you do not use the remote controller for 2 or 3 months.

Push and pull to the direction of arrow

0274E Pg 19-26(RAI-50NH5) 19/10/05, 2:51 PM20

– 20 –

THE IDEAL WAYS OF OPERATION

Suitable Room Temperature Install curtain or blinds

!

Warning

Freezing temperature is bad for health and a waste of electric power.

It is possible to reduce heat entering the room through windows.

Ventilation Effective Usage Of Timer

At night, please use the “OFF or ON timer

Caution

!

Do not close the room for a long period of time. Occasionally open the door and windows to allow the entrance of fresh air.

operation mode”, together with your wake up time in the morning. This will enable you to enjoy a comfortable room temperature. Please use the timer effectively.

ENGLISH

Do Not Forget To Clean The Air Filter

Dusty air filter will reduce the air volume and the cooling efficiency. To prevent from wasting electric energy, please clean the filter every 2 weeks.

– 21 –

Please Adjust Suitable Temperature

For Baby And Children

Please pay attention to the room temperature and air flow direction when operating the unit for baby, children and old folks who have difficulty in movement.

0274E Pg 19-26(RAI-50NH5) 19/10/05, 2:51 PM21

FOR USER’S INFORMATION

The Air Conditioner And The Heat Source In The Room

Caution

!

If the amount of heat in the room is above the cooling capability of the air conditioner (for example: more people entering the room, using heating equipments and etc.), the preset room temperature cannot be achieved.

Not Operating For A Long Time

When the indoor unit is not to be used for a long period of time, please switch off the power from the mains. If the power from mains remains “ON”, the indoor unit still consumes about 8W in the operation control circuit even if it is in “OFF” mode.

OFF

When Lightning Occurs

!

Warning

To protect the whole unit during lightning, please stop operating the unit and remove the plug from the socket.

Interference From Electrical Products

!

Caution

To avoid noise interference, please place the indoor unit and its remote controller at least 1m away from electrical products.

To prevent interference, place at least 1m away.

Inverter-type fluorescent lamp.

TV

0274E Pg 19-26(RAI-50NH5) 19/10/05, 2:51 PM22

– 22 –

MAINTENANCE

!

CAUTION

Cleaning and maintenance must be carried out by qualified service personnel. Before the cleaning, stop operation and disconnect the power supply.

Clean the filter at least once every one month. This helps save electricity cost.

1. CLEANING OF AIR FILTER

REMOVAL AND ATTACHMENT OF AIR FILTER

ENGLISH

PROCEDURE

1

2

3

Remove the filter from indoor

● Press the mark “PUSH” on the left and

right sides of the suction grille.

● Pull out the filter from the grille.

Remove dust from the filter using a vacuum cleaner. If there is too much dust, use neutral detergent. After using neutral detergent, wash with clean water and dry in the shade.

Install the filter. (Set it with “UP SIDE” mark facing front.) Slot the filter to suction grille and close as original state. (Press the mark “PUSH” at the left and right sides of the suction grille to fix it securely.)

Safety Cable

Air Filter

PUSH

Filter Guide

Grille

Note:

● This model has an air cleaning filter. The cooling capacity is slightly weakened and the cooling

speed becomes slower when the air cleaning filter is used. So, set the fan speed to “HIGH” when using it in this condition.

● Recommended to replace the air cleaning filter after every 3 months for normal usage. Type number

for this air cleaning filter is <SPX-CFH5>. Please use this number for ordering when you want to renew it.

!

CAUTION

● Do not wash with hot water at more than 40°C. The filter may shrink.

● When washing it, shake off moisture completely and dry it in the shade; do not expose it directly to

the sun. The filter may shrink.

● Do not operate the air conditioner with the filter removed. Dust may enter the air conditioner and

cause trouble.

– 23 –

0274E Pg 19-26(RAI-50NH5) 19/10/05, 2:51 PM23

2. CLEANING OF FRONT PANEL

● Wipe it with a soft dry cloth.

● When it is excessively dirty, wipe with soft cloth soaked in lukewarm water or neutral detergent. Then

wipe thoroughly with a soft dry cloth.

!

CAUTION

● Do not splash or direct water to the body of the unit when cleaning it as

this may cause short circuit.

● Never use hot water (above 40°C), benzine, gasoline, acid, thinner or a

brush, because they will damage the plastic surface and the coating.

3. MAINTENANCE AT BEGINNING OF LONG OFF PERIOD

● Running the unit setting the operation mode to (FAN) and

the fan speed to HI for about half a day on a fine day, and dry the whole of the unit.

● Turn off the circuit breaker.

Air

Blow

REGULAR INSPECTION

PLEASE CHECK THE FOLLOWING POINTS EITHER EVERY HALF YEARLY OR YEARLY. CONTACT YOUR SALES AGENT SHOULD YOU NEED ANY HELP.

Is the earth line disconnected or broken?

WARNING

1

2

!

Coming off or breakage of grounding wire may cause malfunction or electrical shock.

Is the mounting frame seriously affected by rust and is the outdoor unit tilted or unstable?

WARNING

!

Outdoor unit may fall or drop if there is extreme rust on mounting frame or outdoor unit is unstably installed. This may cause injury.

3

Confirm

0274E Pg 19-26(RAI-50NH5) 19/10/05, 2:51 PM24

Is the plug of power line firmly plugged into the socket? (Please ensure no loose contact between them).

– 24 –

AFTER SALES SERVICE AND WARRANTY

WHEN ASKING FOR SERVICE, CHECK THE FOLLOWING POINTS.

CONDITION CHECK THE FOLLOWING POINTS

● Is the fuse blown out or the circuit breaker tripped?

When it does not operate

When it does not cool well When it does not hot well

Notes

● In quiet operation or stopping the running, the following phenomena may

occassionally occur, but they are not abnormal for the operation. (1) Slight flowing noise of refrigerant in the refrigerating cycle. (2) Slight rubbing noise from the fan casing which is cooled and then

● The odor will possibly be emitted from the room air conditioner because

the various odor, emitted by smoke, foodstuffs, cosmetics and so on, sticks to it. So please clean the air filter and the evaporator regularly to reduce the odor.

● Is the voltage normal?

● Is the circuit breaker “ON”?

● Is the air filter blocked with dust?

● Does sunlight fall directly on the outdoor unit?

● Is the air flow of the outdoor unit obstructed?

● Are the doors or windows opened, or is there any source of

heat in the room?

● Is the set temperature suitable?

gradually warmed as operation stops.

ENGLISH

●

Please contact your sales agent immediately if the air conditioner still fails to operate normally after the above inspections. Inform your agent of the model of your unit, production number, date of installation. Please also inform him regarding the fault.

●

Power supply shall be connected at the rated voltage, otherwise the unit will be broken or could not reach the specified capacity.

0274E Pg 19-26(RAI-50NH5) 19/10/05, 2:51 PM25

– 25 –

Please note: On switching on the equipment, particularly when the room light is dimmed, a slight brightness fluctuation may occur. This is of no consequence. The conditions of the local Power Supply Companies are to be observed.

Note

● Avoid to use the room air conditioner for cooling operation when the outside temperature is below

21°C (70°F). The recommended maximum and minimum operating temperatures of the hot and cold sides should be as below:

Cooling Heating

Minimum Maximum Minimum Maximum

Indoor

Dry bulb °C2132 2027

Wet bulb °C1523 1219

Outdoor

Dry bulb °C21 43 2 21

Wet bulb °C15 26 1 15

MEMO

.....................................................................................................................................................................................

– 26 –

0274E Pg 19-26(RAI-50NH5) 19/10/05, 2:51 PM26

CONSTRUCTION AND DIMENSIONAL DIAGRAM

MODEL RAI-50NH5

650 (Panel)

600 (Opening on ceiling)

580 (Indoor unit)

400 (Suspension bolt)

64

42

393 (Electric box)

580 (Indoor unit)

650 (Panel)

610 (Suspension bolt)

600 (Opening on ceiling)

Narrow pipe ﬂ6.35

Wide pipe ﬂ12.7

Unit : mm

147

56 18

Wireless remote controller

97 (Drain)

65

Drain outlet

42

Above 300

110

Panel (Optional part RAI-ECPM)

Ceiling

285

32

55

62

230 (Drain)

227 (Electric box)

112

Air outlet

Air inlet Air outlet

Note:

1. Insulated pipes should be used for both the narrow and wide dia. pipes.

2. Piping length is within 20m.

3. Height difference of the piping between the indoor unit and the outdoor unit should be within 10m.

4. An F-cable 1.6mm or 2.0mm dia. X 3 (control side) is used for the connection cable.

0274E Pg 27-30(RAI-50NH5) 19/10/05, 2:57 PM27

– 27 –

CONSTRUCTION AND DIMENSIONAL DIAGRAM FOR OUTDOOR

MODEL RAC-50NH5

Handle

Fixing hole

Air suction

grille

700

100

More than

340

201

2022 298

Handle

96

More than

100

169.5

955

10464

26 850

Holes for anchor bolt

(2-ø12)

507 198

Notch for anchor bolt

(2-ø12 Notchs)

57

12 37

Air outlet

10

1010

320

340

79

More than

100

638

650

More than

Service space

0274E Pg 27-30(RAI-50NH5) 19/10/05, 2:57 PM28

– 28 –

MAIN PARTS COMPONENT

THERMOSTAT

Thermostat Specifications

THERMOSTAT MODEL IC

OPERATION MODE COOL HEAT

MODEL RAI-50NH5 RAI-50NH5

ON 13.0 (55.4) 20.0 (68.0)

OFF 12.7 (54.9) 20.3 (68.5)

ON 21.0 (69.8) 28.0 (82.4)

OFF 20.7 (69.3) 28.3 (82.9)

ON 29.0 (84.2) 36.0 (96.8)

OFF

TEMPERATURE °C (°F)

INDICATION

16

INDICATION

24

INDICATION

32

FAN MOTOR

Fan Motor Specifications

MODEL

RAI-50NH5

POWER SOURCE DC: 0 ~ 35V

OUTPUT 25W

CONNECTION

0~35V

5V

28.7 (83.7) 36.3 (97.9)

RAC-50NH5

DC360V

40W

RED

YEL

BLU

M

360V

0V

15V

0~6V

0~15V

RED

BLK

WHT

YEL

BLU

M

(Control circuit built in)

BLU : BLUE YEL : YELLOW BRN : BROWN WHT : WHITE

GRY : GRAY ORN : ORANGE GRN : GREEN RED : RED

BLK : BLACK PNK : PINK VIO : VIOLET

– 29 –

0274E Pg 27-30(RAI-50NH5) 19/10/05, 2:57 PM29

COMPRESSOR MOTOR

Compressor Motor Specifications

MODEL

COMPRESSOR MODEL

RAC-50NH5

JU1013D

PHASE SINGLE

RATED VOLTAGE AC 220 ~ 240 V

RATED FREQUENCY 50 Hz

POLE NUMBER 4

(U)

CONNECTION

M

WHITE

M

(W)

(V)

YELLOW

RESISTANCE VALUE

20°C

(68°F)

2M = 1.05

RED

75°C

(167°F)

YELLOW

2M = 1.28

WHITE

RED

!

CAUTION

( )

When the refrigerating cycle has been operated for a long time with the capillary tubes clogged or crushed or with too little refrigerant, check the color of the refrigerating machine oil inside the compressor. If the color has been changed conspicuously, replace the compressor.

0274E Pg 27-30(RAI-50NH5) 19/10/05, 2:57 PM30

– 30 –

WIRING DIAGRAM

MODEL RAI-50NH5 / RAC-50NH5

INDOOR UNIT OUTDOOR UNIT

0274E Pg 31(RAI-50NH5) 19/10/05, 2:59 PM1

– 31 –

CIRCUIT DIAGRAM

1 2 3 4 5 6 7 8

10 11

13 14 15 16 17

19 20

9

12

18

SEG19 SEG18 SEG17 SEG16 SEG21 SEG24 SEG25 SEG26 SEG27 SEG28

NC NC NC NC NC

NC NC NC

NC

SEG20

SEG5 SEG0 SEG1 SEG2 SEG3 SEG4

SEG5 SEG6 SEG7

COM3 COM2 COM1 COM0

SEG14

SEG13 SEG12 SEG11 SEG13

SEG9

SEG8

40 39 38 37 36 35 34 33

31 30

28 27 26 25 24

22 21

32

29

23

40 39 38 37 36 35 34 33

31 30

28 27 26 25

32

29

64

63

62

61

60

59

58

57

56

55

54

53

52

51

50

49

48 47

46

45

44

43

41

42

65

66 67 68 69 70 71 72

74 75

77 78 79 80

73

76

1

2

3

4

5

6

7

8

9

10

11

12

13

14

15

16

17 18

19

20

21

22

24

23

SEG20 SEG21 SEG22 SEG23 SEG24 SEG25 SEG26 SEG27 SEG28 SEG29 SEG30 SEG31 SEG32 SEG33 SEG34 SEG35

SEG19

SEG18

SEG17

SEG16

SEG15

SEG14

SEG13

SEG12

SEG11

SEG10

SEG9

SEG8

SEG7

SEG6

SEG5

SEG4

SEG3

SEG2

SEG1

SEG0

SEG43

SEG42

SEG41

SEG40

P40

P41

P42

P43

P00

P01

P02

P03

P10

P11

P12

P13

D0

D1

D2

D3

D4

D5

D6

D7

D8

D9

BEEP

P20

P30 P31

NCVL C1

VL C2 VL C3 XC IN

XC OUT

VDD

X OUT

X IN

RESET

CARR

P23 P22

P21

VSS

IC 1 M3455OM6A-504FP

LCD 1

C8

50v/1u

K 1

D3

RB425D(1/2)

K2K3

K4

K5

P10

P11

P12

K6

K7 K8

K9 K10

K11K12

K18

K17

K15 K16

K13 K14

D0

D1

D2

D3

R1

100k

SW1

R2

P

100k

R3

100k

R4

100k

R5

Q1

2SC3443

or 2SC2982

R6

R7

R9

D2D1

D1 D2

EL-1L7

D3

(1/2)

RB425D

R10 12M

K19

X1

C9

R11

R15

R16

R13

R14

910kHz

105

104

150k

X2

kHz

C4

C5

C6

C7

18p

22p

R12

220k

220K

220k

100k

32.768

C1

C2

C3

220p

334

R6 R9

24(1/8W)

R8

330

SW-187-2P

Remote Control

Key matrix table

Output

Input

D0

D3D2D1

Door open Automatic swingFan speed selectionOperation selectionStart/Stop

P10

Door shut ––Automatic swingStart/Stop

Door open Day

• present timeHour downHour upOn timer

P11

Door shut Fan speedRoom temperature downRoom temperature up–

Door open CancelReservation–Off timer

P12

Door shut –––Sleep

– 33 –

0274E Pg 33(RAI-50NH5) 19/10/05, 3:00 PM1

CIRCUIT DIAGRAM

MODEL RAI-50NH5

0274E Pg 35(RAI-50NH5) 19/10/05, 3:09 PM1

– 35 –

CIRCUIT DIAGRAM

MODEL RAC-50NH5

0274E Pg 37(RAI-50NH5) 19/10/05, 3:14 PM1

– 37 –

PRINTED WIRING BOARD LOCATION DIAGRAM

MODEL RAI-50NH5

MAIN P.W.B.

Marking on P.W.B.

COMPONENT SIDE

SOLDERING SIDE

0274E Pg 39-40(RAI-50NH5) 19/10/05, 3:16 PM39

– 39 –

MODEL RAC-50NH5

MAIN P.W.B. Marking on P.W.B

COMPONENT SIDE

0274E Pg 39-40(RAI-50NH5) 19/10/05, 3:16 PM40

– 40 –

Wireless receive circuit

Filter. Operation. Timer.

Auto sweep motor for Air deflector

Drain Pump Motor

LCD wireless

Heat exchanger thermistor

Room temperature thermistor

Reset circuit

Initial setting circuit

Temporary switch

Electric Expansion valve drive circuit

Electric

Expansion

valve

Outdoor microcomputer / HIC (AX-6V00)

Trip signal synthesis circuit

L

N

RAI-50NH5 / RAC-50NH5

SPM2

Outdoor unit Terminal board

Indoor microcomputer (AX-7R11)

0274E Pg 41(RAI-50NH5) 19/10/05, 3:23 PM1

– 41 –

47.

0274E Pg 43(RAI-50NH5) 19/10/05, 3:24 PM1

– 43 –

Table 1 Mode data file

RAI-50NH5

LABEL NAME VALUE

WMAX 6000 min

WMAX2 6000 min

WSTD 4250 min

WBEMAX 3500 min

CMAX 4700 min

CMAX2 4700 min

CSTD 4100 min

CKYMAX 3500 min

CJKMAX 2700 min

CBEMAX 2000 min

WMIN 1800 min

CMIN 1800 min

–1

STARTMC 60 Seconds

DWNRATEW 80%

DWNRATEC 80%

SHIFTW 4.00°C

SHIFTC –2.99°C

CLMXTP 30.00°C

YNEOF 21.00°C

TEION 2.00°C

TEIOF 6.00°C

SFTDSW 2.66°C

DFTIM1 50 Minutes

DFTIM2 90 Minutes

DFTIM3 60 Minutes

0274E pg 45(RAI-50NH5) 19/10/05, 3:25 PM45

– 45 –

Reversing valve (heating “on” mode)

NOTE (9)

Table 2 ∆TCMAX

Temperature Calculated

difference compressor rpm

1.66 2265 min

2 2435 min

2.33 2600 min

2.66 2765 min

3 2935 min

3.33 3100 min

3.66 3265 min

4 3435 min

4.33 3600 min

4.66 3765 min

5 3935 min

5.33 4100 min

5.66 4265 min

6 4435 min

6.33 4600 min

6.66 4765 min

7 4935 min

7.33 5100 min

7.66 5265 min

8 5435 min

8.33 5600 min

8.66 5765 min

9 5935 min

9.33 6100 min

9.66 6265 min

10 6435 min

10.33 6600 min

10.66 6765 min

11 6935 min

–1

Notes: (1) Condition for entering into Cool Dashed mode. When fan set to “Hi” or “Auto mode” and temperature difference between indoor temperature and set temperature has a

corresponding compressor rpm (calculated value in Table 7) larger than WMAX.

(2) Cool Dashed will release when i) a maximum 25 minutes is lapsed and ii) room temperature is lower than set temperature –3°C (thermo off) and iii) when room temperature

has achieved setting temperature –1°C then maximum Cool Dashed time will be revised to 20 minutes. And iv) indoor fan is set to Lo and Med fan mode and v) change operation

mode. (3) During Cool Dashed operation, thermo off temperature is set temperature (with shift value) –3°C. After thermo off, operation continue in Fuzzy control mode. (4) Compressor minimum “ON” time and “OFF” time is 3 minutes. (5) During normal cooling mode, compressor maximum rpm CMAX will maintain for 60 minutes if indoor temperature is lower than CLMXTP. No time constrain if indoor temperature

is higher than CLMXTP. (6) When fan is set to “Hi”, compressor rpm will be limited to CKYMAX. (7) When fan is set to “Med”, compressor rpm will be limited to CJKMAX. (8) When fan is set to “Lo”, compressor rpm will be limited to CBEMAX. (9) During Cool Dashed, when room temperature reaches set temperature –1°C compressor rpm is actual rpm x DWNRATEC.

Note:

1. See the data in Table 1 on page 45 for each constant in capital letters in the diagrams.

– 47 –

0274E Pg 47(RAI-50NH5) 19/10/05, 3:29 PM1

Cooling Sleep Operation

Compressor speed

Horizontal air deflector

Shut

Horizontal

Facing down

Maximum speed

Indoor fan

Outdoor fan

Timer lamp

Operation lamp

Sleep key

(Cooling/dehumidifying set temperature = Remote control set temperature (+) SHIFTC)

Final set temperature (Cooling/dehumidifying set temperature (+) sleep shift)

Set to 7 hours

0.5hr

1.5hr

3hr

P1

2.5hr 3.5hr 6hr 7hr

Hi

See basic operation

Med

Lo (sleep)

Lo

Notes:

(1) The sleep operation starts when the sleep key is pressed. (2) When the sleep key is set, the maximum compressor speed is limited, and the indoor fan is set to “sleep Lo”. (3) 30 minutes after the sleep key is set, the sleep shift of temperature starts, and upper shift is made at least 6 times. If 25˚C

is not reached after 6 shifts, shifts repeat unit 25˚C is reached. (4) The sleep shift upper value of set temperature is 28˚C. (5) After 6 hours, a shift down to the initial set temperature is made at a rate of 0.33˚C/5 min. (6) If the operation mode is changed during sleep operation, the set temperature is cleared, and shift starts from the point when

switching is made. (7) The indoor fan speed does not change even when the fan speed mode is changed. (8) When operation is stopped during sleep operation, the set temperature when stopped, as well as the time, continue to be

counted. (9) If the set lime is changed during sleep operation, all data including set temperature, time, etc. is cleared and restarted. (10) If sleep operation is canceled by the cancel key or sleep key, all data is cleared.

0274E Pg 49(RAI-50NH5) 19/10/05, 3:30 PM1

– 49 –

+

Delay

–1.33˚C

–0.66˚C

0274E Pg 51(RAI-50NH5) 19/10/05, 3:31 PM1

Notes:

(1) If the room temperature is (cooling preset temperature) - (1.33°C) or less after 30 seconds from starting the operation, the operation is done assuming

as the preset temperature = (room temperature at the time) - (2°C). (2) The indoor fan is operated in the “Lo” mode. During thermo OFF indoor fan will be OFF for 5 minutes and ON for 1 minute. (3) When the operation is started by the themostat turning ON, the start of the indoor fan is delayed 32 seconds after the start of compressor operation. (4) The compressor is operated forcedly for 3 minutes after operation is started. (5) The minimum ON time and OFF time of the compressor are 3 minutes.

– 51 –

1.33˚C.

SFTDSW

0.66˚C.

Fan speed set to "auto"

1 min.

Hi

Lo Hi Hi Hi

ultra Hi

Basic Heating Operation

Start

Stop Start Start StopStop

Thermo

OFF

Thermo

OFF

Heating set temperature (remote control set temperature (+))

Start/stop switch

Thermo judgment

Indoor fan

Ultra-Hi

Hi

Med

Lo

Ultra-Lo

Operation lamp

Max.

Rating

3000

0

Compressor speed

Outdoor fan

Reversing valve (heating "on" model)

Thermo OFF

Dash period

TWMAX

Wtd

Defrost signal

Preheating judgment

30sec. 30sec.

10sec.

15sec. 15sec.

15sec. 15sec. 15sec.

10sec.

15sec.

150sec. Delay

150sec. Delay150sec. Delay

3min.

Max. 3 min.

Preheating released

Control by heat exchanger temperature

15sec.

Control by heat exchanger temperature

18˚C

10sec.

30sec. 30sec.

10sec.

30sec. 30sec.30sec. 30sec. 30sec. 30sec.

10sec.

Preheat released

WMIN

(WSTD)

(WMAX)

NOTE (11)

WMAX2

Notes: (1) Condition for entering into Hot Dashed mode. When fan set to “Hi” or “Auto mode” and i) Indoor temperature is lower than 18°C, and ii) outdoor temperature is lower than 10°C,

and iii) Temperature difference between indoor temperature and set temperature has a corresponding compressor rpm (calculated value in Table 3) larger than WMAX. (2) Hot Dashed will release when i) Room temperature has achieved the set temperature + SFTDSW. ii) Thermo off. (3) During Hot Dashed operation, thermo off temperature is set temperature (with shift value) +3°C. After thermo off, operation continue in Fuzzy control mode. (4) Compressor minimum “ON” time and “OFF” time is 3 minutes. (5) During normal heating mode, compressor maximum rpm WMAX will maintain for 120 minutes if indoor temperature is higher than 18°C. No time limit constrain if indoor temperature

is lower than 18°C and outdoor temperature is lower than 2°C. (6) During Hotkeep or Defrost mode, indoor operation lamp will blink at interval of 3 seconds “ON” and 0.5 second “OFF”. (7) When heating mode starts, it will enter into Hotkeep mode if indoor heat exchanger temperature is lower than YNEOF + 0.33°C. (8) When fan is set to “Med” or “Lo”, compressor rpm will be limited to WBEMAX. (9) In “Ultra-Lo” fan mode, if indoor temperature is lower than 18°C, indoor fan will stop. If indoor temperature is higher than 18°C + 0.33°C, fan will continue in “Ultra-Lo” mode.

During Hotkeep or Defrost mode, fan will continue in “Ultra-Lo” mode. (10) During Hot Dashed or outdoor temperature is lower than –5°C, compressor rpm is WMAX2. (11) During Hot Dashed, when room temperature reaches set temperature + SFTDSW compressor rpm is actual rpm x DWNRATEW.

Table 3 ∆TWMAX

Temperature Calculated

difference compressor rpm

1.66 1965 min

2 2135 min

2.33 2300 min

2.66 2465 min

3 2635 min

3.33 2800 min

3.66 2965 min

4 3135 min

4.33 3300 min

4.66 3465 min

5 3635 min

5.33 3800 min

5.66 3965 min

6 4135 min

6.33 4300 min

6.66 4465 min

7 4635 min

7.33 4800 min

7.66 4965 min

8 5135 min

8.33 5300 min

8.66 5465 min

9 5635 min

9.33 5800 min

9.66 5965 min

10 6135 min

10.33 6300 min

10.66 6465 min

11 6635 min

–1

Notes:

1. See the data in Table 1 on page 45 for each constant in capital letters in the diagrams.

0274E Pg 53(RAI-50NH5) 19/10/05, 3:32 PM1

– 53 –

1 min

WMIN

TDF TDF TDF

TDF

Setting Defrosting Inhibit Period

D F T I M 3

D F T I M 2

Time

Outdoor temperature

– 1 0 – 5˚C0˚C

D F T I M 1

Notes: (1) The sleep operation starts when the sleep key is pressed. (2) When the sleep key is set, the maximum compressor speed is limited to WSTD+2000/2, and the indoor fan is set

to “sleep Lo”. (3) 30 minutes after the sleep key is set, the sleep shift of set temperature starts. (4) The maximum sleep shift of set temperature is 5°C, and the minimum is 12°C. (5) If the operation mode is changed during sleep operation, the changed operation mode is set and sleep control

starts. (6) The indoor fan speed does not change even when the fan speed mode is changed. (Lo) (7) When defrosting is to be set during sleep operation, defrosting is engaged and sleep operation is restored after

defrosting. (8) When operation is stopped during sleep operation, the set temperature when stopped, as well as the time, continue

to be counted. (9) If the set time is changed during sleep operation, all data including set temperature, time, etc. is cleared and

restarted. (10) If sleep operation is canceled by the cancel key or sleep key, all data is cleared.

Notes: (1) The first inhibit time after operation start is set to DFTIM1. (2) From the second time onwards, the inhibit time is set according to the time required for

0274E Pg 55(RAI-50NH5) 19/10/05, 3:33 PM1

defrosting. Reverse cycle operation time ≥ [DEFCOL] : DFTIM1 is set. Reverse cycle operation time < [DEFCOL] : The time corresponding to outdoor temperature is set.

– 55 –

REFRIGERATING CYCLE DIAGRAM

MODEL RAI-50NH5

RAC-50NH5

COOLING, DEHUMIDIFYING, DEFROSTING

OUTDOOR UNIT

ELECTRIC EXPANSION VALVE

STRAINER

COMPRESSOR

REVERSING VALV E

SERVICE VALVE

SUCTION TANK

(1/4)

(1/2)

ADAPTOR

INDOOR UNIT

SINGLE-ENDED UNION (3/8)

SINGLE-ENDED UNION (1/4)

HEATING

OUTDOOR UNIT

ELECTRIC EXPANSION VALVE

STRAINER

COMPRESSOR

REVERSING VALV E

SERVICE VALVE

(1/2)

SUCTION TANK

(1/4)

ADAPTOR

INDOOR UNIT

SINGLE-ENDED UNION (3/8)

SINGLE-ENDED UNION (1/4)

0274E Pg 57-88(RAI-50NH5) 19/10/05, 3:34 PM57

– 57 –

REFERENCE

INITIALIZE AT NEXT

OPERATION.

OPERATING SPECIFICATION

INITIALIZE AT NEXT

OPERATION.

ONE SWING (CLOSING AIR DEFLECTOR)

PRESENT CONDITION

OPERATION OPERATION MODE AIR DEFLECTOR

STOP AT THE MOMENT.

1 DOWNWARD

2 UPWARD

STOP

DURING ONE SWING

EACH MODE

STOP

START SWINGING

1 DOWNWARD

2 UPWARD

STOP

AUTO COOL

COOL

FAN

STOP AT THE MOMENT.

3 DOWNWARD

DURING SWINGING

AUTO DRY

DRY

DURING

START SWINGING

1 DOWNWARD

2 UPWARD

3 DOWNWARD

STOP

AUTO HEAT

HEAT

CIRCULATOR

OPERATION

START SWING AGAIN.

STOP AT THE MOMENT.

DURING SWINGING

STOP SWINGING TEMPORARILY.

(SWING MODE IS CLEARED IF SWING COMMAND IS

TEMPORARY STOP

AUTO DRY

DURING SWINGING

DRY

AUTO HAET

HEAT

DURING

OPERATION

INITIALIZE

TRANSMITTED DURING TEMPORARY STOP.)

COOL

CIRCULATOR

1 DOWNWARD

2 UPWARD

INITIALIZE

STOP

DURING ONE SWING

STOP

FAN

DRY

HEAT

STOP

ONE SWING (CLOSING AIR DEFLECTOR)

1 DOWNWARD

DURING ONE SWING

STOP

CIRCULATOR

INITIALIZING CONDITION OF EACH MODE.

1 DOWNWARD

2 UPWARD

DURING SWINGING

DURING

INITIALIZING

EACH MODE

DURING

OPERATION

STOP SWINGING AND MODE BECOMES INITIALIZING

CONDITION.

STOP

DURING SWINGING

EACH MODE

DURING

OPERATION

INPUT SIGNAL

AUTO SWING FUNCTION

MODEL: RAI-50NH5

0274E Pg 57-88(RAI-50NH5) 19/10/05, 3:34 PM58

KEY INPUT

– 58 –

THERMO. ON

(INTERNAL FAN

ON)

THERMO. ON

(INTERNAL FAN

OFF)

MAIN SWITCH

ON

MAIN SWITCH

OFF

CHANGE OF

OPERATION

DESCRIPTION OF MAIN CIRCUIT OPERATION

MODEL RAI-50NH5

1. Reset Circuit

5V

2

R522

1

C521

R521

5

C524

NORMAL : HI RESET : LO

RES

7

Microcomputer

C522

Voltage

Voltage supply to

2

of IC521

Reset release at 4.4V

3

IC521

0V

Fig. 1-1

5.0V

Reset enter at 4.2V

voltage

Voltage at pin of microcomputer

7

5.0V

Fig. 1-2

● The reset circuit initializes the microcomputer program when power is ON or OFF.

● Low voltage at pin 7 resets the microcomputer and Hi activates the microcomputer.

● When power “ON” 5V voltage rises and reaches 4.4V, pin 1 of IC521 is set to “Hi”. At this time the

microcomputer starts operation.

● When power “OFF” voltage drops and reaches 4.2V, pin 1 of IC521 is set to “Low”. This will RESET the

microcomputer.

– 59 –

0274E Pg 57-88(RAI-50NH5) 19/10/05, 3:34 PM59

2. Receiver Circuit

R412

5V12V

R411

R413

C413

C412

C411

ZD411

0V

IRR

V

DD

GND

out

V

R611

C414

13

RECEIVER I/P

C611

0V

Microcomputer

Fig. 2-1

● The light receiver unit receives the infrared signal from the wireless remote control. The receiver amplifies

and shapes the signal and outputs it.

3. Buzzer Circuit

12V

R722

BZ

Microcomputer

Buzzer output

● When the buzzer sounds, an approx.

3.9kHz square signal is output from buzzer output pin of the microcomputer. After

30

the amplitude of this signal has been set to 12Vp-p by a transistor, it is applied to the buzzer. The piezoelectric element in the buzzer oscillates to generate the buzzer’s sound.

30

Fig. 3-1 Buzzer Circuit

Metal diaphragm

Sound wave

0V

Q722

Pizoelectric element

V

0274E Pg 57-88(RAI-50NH5) 19/10/05, 3:34 PM60

Fig. 3-2 Buzzer Operation

– 60 –

D712

P.W.B. MAIN

12V

CN8

Auto sweep motor for horizontal air deflector

Rotor

AUTO SWEEP

M

MOTOR

AUTO SWEEP

M

MOTOR

AUTO SWEEP

M

MOTOR

CN7

1

2

3

4

5

6

7

8

9

10

11

1

2

3

4

5

6

7

8

9

10

4. Auto Sweep Motor Circuit

22

21

20

Microcomputer

19

18

17

16

15

R711

IC711

7

6

5

4

3

2

1

R712

C712

9

8

Q711

Q712

0V

10

11

12

13

14

15

16

C711

0V

Fig.4-1

● Fig. 4-1 shows the Auto sweep motor drive circuit; the signals shown in Fig.4-2 are output from pins

15 – 22 of microcomputer.

Microcomputer pins Step width

Horizontal air deflectors

15

16

12345678

Horizontal air

deflectors: 10ms.

17

18

19

20

21

22

Fig.4-2 Microcomputer Output Signals

● As the microcomputer’s outputs change as shown in Fig.4-2, the core of the auto sweep motor is excited

to turn the rotor. Table 4-1 shows the rotation angle of horizontal air deflectors.

Table 4-1 Auto sweep Motor Rotation

● The air deflectors are driven by the stepping motors, which are instructed by the microcomputer.

● The air deflectors on the left and right are each driven by two stepping motors.

● The stepping motors and main unit are connected via relay connectors. The air deflectors will not operate

unless the relay connectors are connected: Securely connect the relay connectors identified by colors when attaching the panel.

● Before removing the panel for servicing, be sure to disconnect the relay connector to protect the lead

wires.

0274E Pg 57-88(RAI-50NH5) 19/10/05, 3:34 PM61

Rotation angle per step (˚ ) Time per step (ms.)

0.0882 10Horizontal air deflectors

– 61 –

5. Room Temperature Thermistor Circuit

● Fig. 5-1 shows the room temperature

● The voltage at depends on the room

thermistor circuit.

5V

Room temperature thermistor

A

0V

R301

R305

0V

Fig. 5-1

C302

Microcomputer

Room

62

temp. input

5

4

(V) A

3

2

Voltage at

1

0

6. Heat exchanger temperature thermistor circuit

A

temperature as shown in Fig. 5-2.

010

Room temperature (˚C)

20 30 40

Fig. 5-2

5V

Heat exchanger temperature thermistor

R302

A

0V

● The circuit detects the indoor heat

exchanger temperature and controls the following.

(1) Preheating.

(2) Low-temperature defrosting during cooling and dehumidifying operation.

(3) Detection of the reversing valve non-operation or heat exchanger temperature thermistor open.

The voltage at depends on the

A

heat exchanger temperature as shown in Fig. 6-2.

R306

Fig. 6-1

C303

0V

5

4

(V)A

3

2

Voltage at

1

0

Microcomputer

Heat

61

exchanger temperature input

-10

010

20 30 40

0274E Pg 57-88(RAI-50NH5) 19/10/05, 3:34 PM62

Heat exchanger temperature (˚C)

Fig. 6-2

– 62 –

7. Initial Setting Circuit (IC401)

● When power is supplied, the microcomputer reads the data in IC401 (E

2

PROM) and sets the preheating

activation value and the rating and maximum speed of the compressor, etc. to their initial values.

● Data of self-diagnosis mode is stored in IC401; data will not be erased even when power is turned off.

5V

5V 5V

1

2

3

4

IC401 (E

0V

2

PROM)

8

7

6

5

0V

C401

0V

R404

R403

27 26

SCL SDA

Microcomputer

External ROM

}

Fig. 7-1

0274E Pg 57-88(RAI-50NH5) 19/10/05, 3:34 PM63

– 63 –

Model RAI-50NH5

1. Power Circuit

TERMINAL

BOARD

25A FUSE

L

SURGEABSORBER

N

VARISTOR3

L001

C001

VARISTOR1

C002

CT1

C009

0V

NF COIL1

C003

R001

C004C005

COIL

C006

POWER RELAY

R007

R008

ICP RELAY

DIODE

STACK 1

(D25VB60)

SPM2

TB8

TB2

REACTOR

L1 L2

TB7 TB6

TB10

U

Vdba

N1

P1

TB11 TB12

V W

3A FUSE

VARISTOR2

STACK 2 (RC2)

C010

C011

POWER CIRCUIT

R010R011

DIODE

L002

C014

C015

C012

C013

C007 C008

JW6

R002

Fig. 1-1

● This circuit full-wave rectifies 220-240V AC applied between terminals L and N, and boosts it to a required

voltage with the active module, to create a DC voltage.

The voltage becomes 260-360V when the compressor is operated

(1) Active module

The active filter, consisting of a reactor and switching element, eliminates higher harmonic components contained in the current generated when the compressor is operated, and improves the power-factor.

< Reference >

● In case of malfunction or defective connection:

Immediately after the compressor starts, it may stop due to “abnormally low speed” active error, etc.

The compressor may continue to operate normally, but the power-factor will decrease, the operation current will increase, and the overcurrent breaker

(2) Diode stacks

These rectify the 220-240V AC from terminals L and N to a DC power supply.

of the household power board will probably activate.

● In case of active module faulty or defective

connection:

Although the compressor continues to operate normally, the power-factor will decrease, the operation current will increase, and the overcurrent breaker of the household power board will probably activate.

< Reference >

● If diode stack 1 is faulty, the compressor may stop

due to “lp”, “anbormally low speed”, etc. immediately after it starts, or it may not operate at all because no DC voltage is generated between the positive e and negative d terminals.

If diode stack 1 is faulty, be aware that the 25A fuse might also have blown.

● If diode stack 2 is faulty, DC voltage may not be

generated and the compressor may not operate at all. Also, be aware that the 3A fuse might have blown.

0274E Pg 57-88(RAI-50NH5) 19/10/05, 3:34 PM64

– 64 –

(3) Smoothing capacitor (C501, C502, C503)

This smoothes (averages) the voltage rectified by the diode stacks.

<Notes> Smoothing capacitor C501 is not available for model RAC-50NH5.

Smoothing Capacitors

SPM2

Fig. 1-2

a

b

DC voltage

Vd

(approx. 260-360V during operation)

OV

Fig. 1-3

(4) Smoothing capacitor (C010, C011)

This smoothes (averages) the voltage rectified by the diode stack2. A DC voltage is generated in the same way as in Fig. 1-3. Voltage between + side of C010 and – side of C011 is about 330V.

(5) C001 to C003, C012 to C015, C007, C008, NF COIL1, COIL,

absorb electrical noise generated during operation of compressor, and also absorb external noise entering from power line to protect electronic parts.

(6) Surge absorber, Varistor 1, 2, 3,

absorbs external power surge.

(7) Inrush protective resistor (R007, R008)

This works to protect from overcurrent when power is turned on.

● Be careful to avoid an electric shock as a

high voltage is generated. Also take care not to cause a short-circuit through incorrect connection of test equipment terminals. The circuit board could be damaged.

< Reference >

● When inrush protective resistor is

defective, diode stack may malfunction. As a result, DC voltage is not generated and no operation can be done.

0274E Pg 57-88(RAI-50NH5) 19/10/05, 3:34 PM65

– 65 –

2. Indoor/Outdoor Interface Circuit

● The interface circuit superimposes an interface signal on the DC 35V line supplied from the outdoor unit

to perform communications between indoor and outdoor units. This circuit consists of a transmiting circuit which superimposes an interface signal transmit from the microcomputer on the DC 35V line and a transmiting circuit which detects the interface signal on the DC 35V line and outputs it to the microcomputer.

● Communications are performed by mutually transmiting and receiving the 4-frame outdoor request signal

one frame of which consists of a leader of approx. 100 ms., start bit, 8-bit data and stop bit and the command signal with the same format transmit from the indoor unit.

● Communication signal from outdoor microcomputer to indoor microcomputer. At first outdoor microcomputer

will send a request signal (SDO) to indoor microcomputer. A high-frequency IF signal approx. 38 KHz is generated and modulated by the request signal (SDO) inside the outdoor microcomputer then output to

11

of microcomputer. This modulated IF signal is output to pin 30 of HIC and amplified by amp. This

pin signal is superimposed to DC 35V line via C801 and L801. To prevent erroneous reception, the outdoor microcomputer is designed so that it cannot receive a signal while it is outputting a request signal. The receiving circuit in the indoor unit consists of a comparator and transistor. The interface signal from the outdoor unit on the DC 35V line is supplied to C821, where DC components are eliminated, and is then shaped by the comparator. The shaped signal is detected by diode, amplified by amp, and output

49

to pin Fig. 2-2 shows the voltages at each component when data is transferred from the outdoor microcomputer to the indoor microcomputer.

● Communication signal from indoor microcomputer to outdoor microcomputer. The request signal (SDO)

generates by indoor microcomputer is output to pin is generated by comparator, then modulate by the request signal from pin This modulated IF signal is then amplified and superimposed to DC 35V line via L801 and C802 of indoor interface circuit. Fig. 2-3 shows the voltages at each component when data is transferred from outdoor microcomputer to indoor microcomputer. The circuit operation of the outdoor receiving circuit is same as indoor receiving circuit.

of the indoor microcomputer.

50

, and amplifies by C801. IF signal approx. 38 kHz

50

of indoor microprocessor.

0274E Pg 57-88(RAI-50NH5) 19/10/05, 3:34 PM66

– 66 –

● Fig. 2-1 shows the interface circuit used for the indoor and outdoor microcomputers to communicate with

each other.

C802

I/F 0V

D101

L801

C803

5V

C804

0V

C821 R821

Terminal board

CD

Terminal board

R813

R812

Q803

C822

R810

Q802

R811

0V

5V 5V 5V

R822

R823

0V 0V0V

Indoor P.W.B.

Outdoor P.W.B.

35V

R825

R824

3 2

IC801

5V5V

R807

1

R805

IC801

7

R806

C823

R826 D821

5V

R828

5V

0V

R803

R804

Q821

5V

0V

R829

R830

Q801

0V

HIC

C824

IF transmit

50

output (SDO)

MICROCOMPUTER

IF receive

49

input (SDI)

5

6

C801

0V

R827

0V

Interface relay

0V

L802

12V

C811

C812

C807

C808

0V

L801

C801

0V

C806

NF COIL2

5V

C809

C810

I/F 0V

R801

R802 Q801

29

C802

IF transmit

11

output (SDO)

0V

30

R803

0V0V

5V

5V 5V

0V

5V

0V

MICROCOMPUTER

68

0V

IF receive input (SDI)

(Communications from outdoor microcomputer to indoor microcomputer)

(Communications from indoor microcomputer to outdoor microcomputer)

0274E Pg 57-88(RAI-50NH5) 19/10/05, 3:34 PM67

Fig. 2-1 Indoor/outdoor interface Circuit

– 67 –

Outdoor HIC

30

29

0.7V

0V

5V

0V

Indoor microcomputer

DC 35V line

50

49

100ms. Leader

33ms. 1 frame

5V

0V

5V

0V

35V

Fig. 2-2 Voltages Waveforms of indoor / Outdoor Microcomputers (Outdoor to Indoor Communications)

Outdoor HIC

30

0V

29

Indoor microcomputer

DC 35V line

50

49

4.95ms. Transmit / receive switching time

33ms. 1 frame

5V

0V

5V

0V

5V

0V

35V

Fig. 2-3 Voltages Waveforms of indoor / Outdoor Microcomputers (Indoor to Outdoor Communications)

0274E Pg 57-88(RAI-50NH5) 19/10/05, 3:34 PM68

– 68 –

[Serial Communications Format during Normal Communications]

(1) Outdoor microcomputer (HIC) to indoor microcomputer

(2) Indoor microcomputer to outdoor microcomputer (HIC)

(3) Communications waveforms

1 frame = 100ms. + 33.3ms. x 8 + 4.95ms. = 371.35ms.

Outdoor message

Indoor message

[Example] When the outdoor message is all 0s

and indoor message is all 1s:

36 (V)

35 (V)

34 (V)

When reset

(approx. 10ms.)

Transmit/

receive

switching time

(4.95ms.)

Character No.

0

(33.3ms.)

1

(33.3ms.)

2

(33.3ms.)

3

(33.3ms.)

Character No.

0

(33.3ms.)

1

(33.3ms.)

2

(33.3ms.)

3

(33.3ms.)

Bit No = 0

07

0707077

07077

Leader

(100ms.)

When reset

(approx. 10ms.)

Leader

(100ms.)

Fig. 2-4

0274E Pg 57-88(RAI-50NH5) 19/10/05, 3:34 PM69

– 69 –

7

6

5

4

0

3

2

1

Fan-7-step request

0

7

Actual compressor rotation speed (5 MSB)

6

Actual compressor rotation speed (4)

5

Actual compressor rotation speed (3)

4

2

1

0

Actual compressor rotation speed (2)

3

Actual compressor rotation speed (1)

2

Actual compressor rotation speed (0 LSB)

1

Compressor during operation

0

Compressor during operation

7

Outside temperature (7 MSB)

6

Outside temperature (6)

5

Outside temperature (5)

4

Outside temperature (4)

3

Outside temperature (3)

2

Outside temperature (2)

1

Outside temperature (1

0

Outside temperature (0 LSB)

7

Self-diagnosis (3 MSB)

6

Self-diagnosis (2)

5

Self-diagnosis (1)

4

Self-diagnosis (0 LSB)

3

Defrost request signal

2

During forced operation

1

0

Multi-bit

0

1

0

1/0

1/0 1/0 1/0 1/0 1/0 1/0 1/0 1/0 1/0 1/0 1/0 1/0 1/0 1/0 1/0

1/0

1/0 0

1/0

7

Compressor minimum rotation speed (4 MSB)

6

Compressor minimum rotation speed (3)

5

Compressor minimum rotation speed (2)

4

3

Compressor minimum rotation speed (1)

3

Compressor minimum rotation speed (0 LSB)

2

1

OVL up

0

15/20(A)

7

Compressor command speed (7 MSB)

6

Compressor command speed (6)

5

Compressor command speed (5)

4

2

Compressor command speed (4)

3

Compressor command speed (3)

2

Compressor command speed (2)

1

Compressor command speed (1)

0

Compressor command speed (0 LSB)

7

Compressor ON

1/0

6

5

4

1

0

Reversing valve

3

2-way valve

2

Fan (2 MSB)

1

Fan (1

0

Fan (0 LSB)

7

Capacity code (3 MSB)

6

Capacity code (2)

5

Capacity code (1)

4

Capacity code (0 LSB)

3

Indoor in-operation bit

2

Operation mode (2 MSB)

1

Operation mode (1)

0

Operation mode (0 LSB)

0 0 0 1/0 1/0 1/0 0 1/0 0 0 1/0 1/0 1/0 1/0 1/0

0

1/0

Bit No.

Character No.

(1) Outdoor message

[ Serial Communications Data ]

0274E Pg 57-88(RAI-50NH5) 19/10/05, 3:34 PM70

Contents

Data

Character No.

(2) Indoor message

– 70 –

Bit No.

Contents

Data

+

W

U

V

W

–

+

V

–

+

U

–

A

+

DC

Compressor

motor

U coil

V coil

W coil

System Power module 2

+

–

C501

+

–

C502

+

–

C503

R24

0.35

m

H

Power relay

Coil

R007

R008

Inrush current

protection

relay

C006

R001

Noise filter

coil

L

N

Terminal

board

FUSE (25A)

3. Power Module Circuit

is ON)

–

is ON, V

+

Fig. 3-1 Power module circuit (U

Fig. 3-1 shows the system power module and its peripheral circuit.

The three transistors on the positive e side are called the upper arm, and the three transistors on the negative d side, the lower arm.

●

– 71 –

0274E Pg 57-88(RAI-50NH5) 19/10/05, 3:34 PM71

● DC 260-360V is input to system power module and system power module switches power supply current

according to rotation position of magnet rotor. The switching order is as shown in Fig. 3-2.

At point E: U+ is ON, V– is ON (circuit in Fig. 3-1) At point F: U+ is chopped (OFF), V– is ON (circuit in Fig. 3-4)

[]

E

F

+

Upper arm transistor

++T+

UVVW

Lower arm transistor

–

U

–

V

–

W

Time

Fig. 3-2 Switching order of power module

● Upper arm transistor is controlled to ON/OFF by 3.3kHz chopper signal. Rotation speed of the compress

is proportional to duty ratio (ON time/ ON time + OFF time) of this chopper signal.

● Time T in Fig. 3-2 shows the switching period, and relation with rotation speed (N) of the compressor is

shown by formula below;

N = 60/2 X 1/T

● Fig. 3-3 shows voltage waveform at each point shown in Figs. 3-1 and 3-4. First half of upper arm is

chopper, second half is ON, and first half of lower arm is chopper, second half is ON.

Voltage at

260V-360V

+

U transistor chopped

A

-

U transistor ON

Upper arm transistor

Current at

B

Chopping period

ON

T

Fig. 3-3 Voltage waveform at each point

● When power is supplied U

+

[ U–, because of that U+ is chopped, current flows as shown below;

(1) When U+ transistor is ON: U+ transistor [ U coil [ V coil [ V– transistor [ DC current detection

resistor [ Point (Fig. 3-1)

B

(2) When U+ transistor is OFF: (by inductance of motor coil) U coil [ V coil [ V– transistor [ Return

diode [ Point (Fig. 3-4)

A

B

0274E Pg 57-88(RAI-50NH5) 19/10/05, 3:35 PM72

– 72 –

260V-360V

+

System Power Module 2

+

U

—

B

R24

U

_

+

V

—

V

+

W

—

W

A

U

V

W

U coil

V coil

DC compressor motor

W coil

DC current (Id) detection resistor

Fig. 3-4 Power module circuit (U+ is ON, V– is ON)

● Since current flows at point only when U+ transistor is ON, the current waveform at point becomes

intermittent waveform as shown in Fig. 3-3. Since current at point is approximately proportional to the

B B

B

input current of the air conditioner, input current is controlled by using DC current (Id) detection resistor.

If power module is detective, self diagnosis lamps on the control P.W.B. may indicate as shown below:

Table 3-1

Self-diagnosis lamp and mode

LD301

Blinks 2 times

Blinks 3 times

Blinks 4 times

P.W.B (Main)

Self diagnosis lamps (LD303, 302, 301)

Self-diagnosis

lp (peak current cut)

Abnormal low speed

rotation

Switching incomplete

Fig. 3-5

● Simplified check of power module (Lighting mode when operated with compressor leads disconnected)

(1) Disconnect connector of 3-pole (WHT, YEL, RED) lead wire connecting to compressor located at the

lower part of electric parts box.

(2) Set to compressor operation state (other than FAN mode) and press Start/stop switch of remote

control.

(3) If normal operation continues for more than 1 minute (LD303 lights), power module is considered

normal.

❈ Refer to other item (troubleshooting on page 94) for independent checking of power module.

0274E Pg 57-88(RAI-50NH5) 19/10/05, 3:35 PM73

– 73 –

4. Power Circuit for P.W.B.

● Fig. 4-1 shows the power circuit for P.W.B. and waveform at each point.

Diode stack 2

R002

(RC2)

+

C010

+

C011

R010

R011

C905

D902

IC901

3 4

2 5

L901

R907

R906

R903

1

C906

R911

R904

+

R901

D911

3

C903

D906

Switching transformer (T1)

R902

C901

D905

D904

R909

R910

R908

C907

D903

PQ1

4

C908

C

4

3

1

9

12

11

C918

PQ2

C924 R922

C909

20

D907

D909

C913

D910

R921

2

3

+

1

REG2

+

C910

+

C911

FM–15V

C912

C914

R916

R925

L903

JW8

1

2

21

22

D908

R915

18

19

R917

16

17

15

14

13

R920

1

VR1

2

L902

R918

FM–0V

JW8

PQ1

R923

R914

35V

0V

R919

I/F0V

17V

12V

+

R924 ZD904

C919

C920

D912

1 2 4 3

REG1

5V

+

C921

0V

Fig. 4-1 Power circuit for P.W.B.

● In the power circuit for P.W.B., power supply for microcomputer, peripheral circuits, and system power

Q706

0V

module driver circuit and, as well as DC 35V, are produced by switching power circuit.

● Switching power circuit performs voltage conversion effectively by switching transistor IC901 to convert

DC 330V voltage to high frequency of about 20kHz to 200kHz.

● Transistor IC901 operates as follows:

(1) Shifting from OFF to ON

● DC about 330V is applied from smoothing capacitors C010 Œ and C011 œ in the control power circuit.

With this power, current flows to pin of IC901 via R903 and R904 and IC901 starts to tum ON. Since voltage in the direction of arrow generates at point at the same time, current passing through R910 and

4

C

D903 is positive-fed back to IC901.

0274E Pg 57-88(RAI-50NH5) 19/10/05, 3:35 PM74

– 74 –

(2) During ON

● The drain current at IC901 increases linearly. During this period, the gate voltage and current become

constant because of the saturation characteristics of the transformer.

(3) Shifting from ON to OFF

● This circuit applies a negative feedback signal from the 12V output. When the voltage across C919

reaches the specified value, REG2 turns on and current flows to PQ2 1-2. This turns the secondary circuits on, sets IC901 pin 1 to “Hi”, and turns IC901 off.

(4) During OFF

● While IC901 is on, the following energy charges the primary windings of the transformer:

2

Energy=LI

/2. Here, L : Primary inductance

I : Current when IC1 is off

This energy discharges to the secondary windings during power off. That is, C910, C911, C912, C914 is charged according to the turn ratio of each winding.

● At the start, an overcurrent flows to IC901 because of the charged current at C910, C911, C912, C914.

● The drain current at IC901 generates a voltage across R906. If it exceeds the IC901 base voltage, it sets

the IC901 gate voltage to “HI”.

● R906 limits the gate voltage to prevent excessive collector current from flowing to IC901.

If the power circuit for P.W.B. seems to be faulty:

(1) Make sure that 5V and 12V on the control P.W.B., upper arm U, V and W, and the lower arm power

voltage are the specified values.

(2) When only the 5V output is low:

REG 1 (regulator) faulty, 5V-0V shorted, output is too high, or REG 1 is abnormal.

(3) When 12V and 5V are abnormal:

The following defects can be considered:

1 Fan, operation, power, rush prevention relay (shorting in relay, etc.) 2 Microcomputer is abnormal. 3 REG 1 (regulator is abnormal), etc.

Shorting on primary circuits. When shorting occurs in the secondary circuits, there is no abnormality in the primary circuits because of overcurrent protection. The voltage rises when an opening occurs in the primary circuits, or the feedback system is abnormal.

(4) When 15V and 17V are abnormal:

D908, D909 or drive circuit is abnormal.

(5) When all voltage are abnormal:

IC901, R906, etc. are possibly abnormal.

* If IC901 is abnormal, be aware that other components, such as the power module, REG (regulator), etc.

are possibly defective.

[When the switching power supply seems to be abnormal, the voltage between IC901 pin 4 (to be measured at the leads of R904 and R903) and IC901 pin 5 (to be measured at R906 lead) may be between 11 and 16V. This is because the protection circuit of IC901 is operating.]

0274E Pg 57-88(RAI-50NH5) 19/10/05, 3:35 PM75

– 75 –

5. Reversing valve control circuit

I/F 35V

Reversing valve

DC voltmeter or tester

5V

CN2

3

1

V

I/F 0V

FUSE RESISTOR

D702

Q701

R701

R702

4

1

PQ701

23

R703

Q705

16

0V

HIC

R219

24

MICROCOMPUTER

Fig. 5 – 1

● Reversing valve control circuit can switch reversing valve ON/OFF according to instruction from indoor

microcomputer depending on the operation condition shows in Table 5-1.

Voltage at each point in each operation condition is approximately as shown below when measured by tester. (When collector voltage of Q701 is measured)

Table 5-1

Operation condition Collector voltage of Q701

Cooling

General operation of Cooling

In normal heating operation

About 35V

About 0.8V

MAX. rotation speed instructed

Heating

by indoor microcomputer after

About 0.8V

defrost is completed

Dehumidifying

Defrosting

Sensor dry

About 35V

0274E Pg 57-88(RAI-50NH5) 19/10/05, 3:35 PM76

– 76 –

6. Rotor magnetic pole position detection circuit

0V

R601

C605

C606

C607

18

19

20

Outdoor microcomputer

R602

C501

+5V

R603

C

D

E

C502

C608

0V

C503

+12V

HIC

System power module

B

36

R604

R605

R606

R607

R604

R603

R602

WV U

33

34

R608

R611

DC brushless motor for compressor

A

0V

47

35

R610

R609

U phase terminal voltage

Spike voltage

Pole position detection signal

Drive signal

No power supplied

60 120 60 120

A

C

D

E

+

W

Upper armONNo power

(B) reference voltage (1/2Vd)

Detection point

+

U

—

V

W

supplied

Induced voltage

Comparing process

+

V

—

Lower arm

ON

—

U

No power supplied

60

+

W

Vd 150 ~ 330

+

U

—

V

Fig. 6-1 Rotor magnetic pole position detection circuit and voltage waveform at each point

 To detect U phase, voltage at point C is produced by driving motor induced voltage signal (voltage at point A ) and

1/2 voltage of Vd (voltage at point B ), and comparing with comparator.

 For V phase and W phase, voltage at point D and voltage at point E are produced in the same way as above. Voltage

C

at point

is taken into indoor unit microcomputer, switching timing to U+ transistor from W+ transistor is produced by delaying 30° from rise waveform, ignoring spike voltage. In addition, switching timing to U-transistor from W-transistor is produced by delaying 30° from fall waveform.

 For V phase and W phase, in the same way as above, drive signals are produced from voltages at point

E

. Phases are shifted by 120° and 240°, respectively, comparing with U phase.

0274E Pg 57-88(RAI-50NH5) 19/10/05, 3:35 PM77

– 77 –

D

and point

7. Drive Circuit

6

5

4

3

2

1

MICROCOMPUTER

A

R512

R521

R511

R510

R509

R508

R507

10

9

4

3

2

1

8

7

6

5

1

13

14

15

16

17

18

1

23

11

8

7

5

4

10

6

3

9

2

3

4

5

6

7

8

9

10

11

12

13

14

15

16

17

18

19

20

21

22

23

24

25

26

27

28

19

20

21

2

3

4

5

6

7

8

9

10

12

22

B

45

44

43

42

41

38

39

40

46

IP CUTTER Id CONTROL CIRCUIT

0V

17V

R501

C404

CN14

17V

0V

PWB (MAIN)

SPM2

0V

17V

U

+

V

+

W

+

U

–

V

–

W

–

IP

Id

IC1

VCC

VCU

PGU

U

VCV

PGV

V

VCW

PGW

W

NGU

NGV

NGW

SVT

SWT

SUB

SVB

SWB

F

OC

CB

A

0

A

–

GL1

GL2

SUT

R502

R503

R504

R505

R506

Q506

R536

R535

R525

Q504

R534

Q503

R524

R533

Q502

Q501

R522

R532

R531

R526

Q505

R523

HIC

P2

N1

HIC

–

+

GRY

R24

U

COMPRESSOR MOTOR

V

W

Fig. 7-1 shows the drive circuit. The circuits for U phase, V phase and W phase have the same Configuration.

th

ignal

nsistor

drive

Fig.. 7-1

In low speed rotation mode (PWM range), as shown in Fig. 7-2, 0-5V chopper signal is ouput from microcomputer for each phase. S

output from microcomputer is ouput to IC1 and is inverted by active Lo to become 0-15V chopper signal; it is then drive the tra

of each phase.

●

0274E Pg 57-88(RAI-50NH5) 19/10/05, 3:35 PM78

In high speed rotation mode (PWM range), as shown in Fig. 7-3, 0-5V drive signal is ouput from microcomputer for each phase (wi

no chopper because of full duty). Signal output from microcomputer is input to IC1 and is inverted by active Lo to become 0-15V

signal; it is then drive the transistor of each phase.

●

– 78 –

[Low speed rotation mode]

-

V

5V

+

A

U

0V

+

V

+

W

-

U

-

V

-

W

Drive signal at point

15V

+

U

0V

+

B

V

+

W

-

U

-

V

-

W

Drive signal at point

+

U

W

-

+

V

-

U

W

+

-

V

+

U

W

-

+

V

Fig. 7-2

[High speed rotation mode]

5V

+

A

U

0V

+

V

+

W

-

U

-

V

-

W

Drive signal at point

15V

+

U

0V

+

B

V

+

W

-

U

-

V

-

W

Drive signal at point

+

U

-

V

W

-

+

V

-

U

W

+

-

V

+

U

W

-

+

V

0274E Pg 57-88(RAI-50NH5) 19/10/05, 3:35 PM79

Fig. 7-3

– 79 –

8. HIC and Peripheral Circuits

● Fig. 8-1 shows the micro computer and its peripheral circuits, Table 8-1, the basic operations of each

circuit block, and Fig. 8-2, the system configuration.

Detection Resistor

R24

N1

R41

R43

DC Current

C34

0V0V

SPM2 – HIC

OC

99

F

8

20

IC1

R42

P2

Direct Current

DC260-380V

10

3938

6

+

C217

R286

C2260VR285

0V

R222

–

+

5

R247

0V

IC4

C225

R245

L

Is

N

CT1

D104

R005

0V

C009

0V0V

R006

C107

0V

+

C105

58

62

JW10

0V

12V

0V

R221

R284

R292

Fig. 8-1 Microcomputer and Peripheral Circuits

7

0V

2

–

+

3

R288

IC5

0V

CN13CN14

C205

R249

R248

C215

1

+

D205

37

0V

5V

R252

19

521

5V

C218

R289

R500

R253

D204

0V

SPM2

MAIN P.W.B

HIC

59

Vd

C222

0V

17

Ip

60

Id

C224

0V

C204

0V

IC1

MICROCOMPUTER

61

Is

48

RESET

Table 8-1

Circuit block

Peak current cutoff circuit

Set value circuit

Voltage amplifier circuit

Reset circuit

Trip signal synthesis circuit

0274E Pg 57-88(RAI-50NH5) 19/10/05, 3:35 PM80

Basic operation

Detects DC current flowing power module and during overcurrent (instantaneous value) flows, stops upper/lower arm drive circuits and also produces lp signal by which drive signal output is stopped.

Compares voltage detected, amplified and input to HIC with set voltage value in microcomputer, and controls overload when set value exceeds input voltage.

Voltage-amplifies DC current level detected by the detection resistor and inputs this to microcomputer. Internal or external overload is judged in microcomputer.

Produces reset voltage.

Modulates chopper signal to drive signal and stops according to presence/absence of lp signal or reset signal.

– 80 –

5V

Reset Voltage

Chopper

signal

Chopper

Trip signal

synthesis circuit

signal

DC 260V

Reset circuit

Over-load external

setting circuit

-360V

IP signal

Current amplified

circuit

DC Current level

Outdoor microcomputer

Fig. 8-2

● The following describes the operations of each circuit in detail.

(1) Peak current cut off circuit Fig.8-3 Peak Current Cut off Circuit and Waveforms at Each Section.

Drive

Circuit

Peak current cut off circuit

Detection

resistor

Drive

signal

DC current

Powe r module

Compressor

motor

DC current Id

21A (27A, for RAC-50NH4)

Voltage at point

1.05V (1.35V for RAC-50NH4)

Voltage at point

SPM2

–

Negative Terminal

DC current

A

R41

A

Detection

resistor

B

0V

9 9

SPM2 – HIC

R43

0V

IC1

QC

R43

0V

B

R42

20 9 2 39 17

8

F

Main P.W.B

CN14

Fig.8-3

● The Ip cut off circuit detects an instantaneous excessive current and stops inverter to protect parts such

as SPM2, etc.

● As shown in diagram, if current exceeding 21A (27A for RAC-50NH5) flows, voltage at point recognized

by detecting resistor is input to pin of SPM2 – HIC, and voltage divided by R41 and R43 is input to pin

9

of IC1. Since threshold of IC1 is exceeded in this case, Lo signal is input from pin (Voltage at point

B

. When Lo signal is input to pin of microcomputer, microcomputer stops drive output.

● When drive output from microcomputer is stopped, all drive output goes Hi, and microcomputer is initialized

10

17

A

8

to enter drive signal standby mode. 3 minutes later, microcomputer outputs drive signal again, to start operation.

HIC

IP Outdoor microcomputer

0274E Pg 57-88(RAI-50NH5) 19/10/05, 3:35 PM81

– 81 –

(2) Overload control circuit (OVL control circuit)

● Overload control is to decrease the speed of the compressor and reduce the load when the load on the

air conditioner increases to an overload state, in order to protect the compressor, electronic components and power breaker.

● Overloads are judged by comparing the DC current level and set value.

● Fig. 8-4 shows the overload control system configuration and Fig. 8-5 is a characteristic diagram of

overload judgement values. There are two judgement methods-external judgement which compares the externally set value with the DC current value regardless of the rotation speed and internal judgement which compares the set value that varies according to the rotation speed programmed in the microcomputer software with the DC current value.

Microcomputer

To power module negative terminal

(R24)

DC current

Detection

resistor

Voltage amp

circuit

(Internal judgement)

DC voltage

OVL judgement with respect to externally set value

A/D

converter

A/D

converter

Judgement OVL according to the rotation speed

Selects data according to the rotation speed and DC voltage

Motor control process

Rotation speed data

OVL start current data

Fig. 8-4 Overload Control System Configuration

DC current

Judgement value according to the rotation speed

(internal judgement value)

Rotation speed

Fig. 8-5

1. Overload external judgement circuit

● Fig. 8-1. The filter consisting of R245 and C217 removes high harmonic components from the voltage

generated by the current flowing to Detection resistor; R245 and C217 average the voltage. This voltage is then input to IC4 pin is then amplified and supplied to microcomputer pin . The microcomputer

5

compares this input with the internally set value, and if the input exceeds the set value, it enters overload control status.

● Fig. 8-7 shows the rotation speed control. When the voltage at pin of the microcomputer exceeds the

60

set value, the microcomputer decreases the rotation speed of the compressor and reduces the load regardless of the rotation speed commanded by the indoor microcomputer.

60

0274E Pg 57-88(RAI-50NH5) 19/10/05, 3:35 PM82

– 82 –

Detection Resistor

R24

N1

L

Is

N

0V

CT1

C009

0V0V

D104

R006

R005

DC Current

58

+

C105

1

5

373938

5V

C218

Direct Current

DC 260-380V

R500

SPM2

MAIN P.W.B.

R253

C222

0V0V

D204

C224

0V

0V0V

59

Vd

60

Id

61

Is

HIC

IC1

Microcomputer

P2

10

1

R245

0V

R221

CN14

+

C217

R247

R222

6

–

+

5

CN13

+

C205

0V

R249

7

R248IC4

D205

Fig. 8-6

Voltage at microcomputer pin

Rotation speed of compressor

60

Commanded rotation speed

Actual rotation speed

Deceleration DecelerationAcceleration Acceleration

Fig. 8-7

2. Voltage amp. circuit

● The voltage amp. circuit amplifies the DC current level detected by the detection resistor after being

converted to a voltage and supplies it to the microcomputer. Receiving this, the microcomputer converts it to a digital signal and compares it with the internal data to judge whether or not overload control is required.

< During overload control >

● The filter consisting of R245 and C217 removes high harmonic components from the voltage generated

from the DC current flowing to the detection resistor, and supplies it to IC4 pin 5 IC4 forms a non-inverting voltage amp. circuit together with the peripheral elements.

● The microcomputer stores the set values which vary according to the rotation speed. When the DC current

level exceeds the set value, the microcomputer enters the overload control state.

● The set Value is determined by the amplification of the voltage amp. circuit.

{

0274E Pg 57-88(RAI-50NH5) 19/10/05, 3:35 PM83

● Amplification : high [ DC current : low

● Amplification : low [ DC current: high

– 83 –

● R500, R253, detect the DC voltage at the power circuit. The microcomputer receives a DC voltage (260-

380V) via HIC

37 and applies correction to the overload set value so the DC current is low (high) when

the DC voltage is high (low).

(Since the load level is indicated by the DC voltage multiplied by DC current, R247, R248, R249 are provided to perform the same overload judgement even when the voltage varies.)

Amplification : low DC voltage : low DC current : high

Amplification : 8.5 times DC voltage : 260V

Amplification : high

DC current

0

G

0

Rotation speed

DC voltage : high DC current : low

Fig. 8-8

< During start current control >

● It is required to maintain the start current (DC current) constant to smooth the start of the DC motor for

the compressor.

● RAC-50NH5 uses software to control the start current.

● The start current varies when the supply voltage varies. This control method copes with variations in the

voltages as follows.

(1) Turns on the power module's U+ and V– transistors so the current flows to the motor windings as shown in Fig8-9.

(2) Varies the turn-ON time of the W+ transistor according to the DC voltage level and the start is controlled so the start current is approx. 10A as shown in Fig. 8-10.

DC 260-360V

Detection

resistor

Chopper duty: high

ON-time

W transistor

20

15

10

5

DC current (A)

0

DC current

Power module

+

U

—

U

+

V

—

V

+

W

—

W

Compressor motor

U V

W

Fig. 8-9

DC voltage: low DC voltage: 280V DC voltage: high

DC voltage (start current)

Start

Set value

Time

Fig. 8-10

0274E Pg 57-88(RAI-50NH5) 19/10/05, 3:35 PM84

– 84 –

9. Temperature Detection Circuit

+5V

O.H. thermistor

CN8

Normal 2.7V or less Over heat 2.7V or more Reset 2.3V or less

HIC

O.H.

627

Microcomputer

DEF.

636

Outdoor

645

temperature

DEF. thermistor

CN9

Outdoor temperature thermistor

CN10

+5V

0V

Normal 2.4V or more Over heat 2.4V or less Reset 2.9V or more

+5V

0V

Refer to the table 10-1

0V

Fig. 9-1

● The Over heat thermistor circuit detects the temperature at the surface of the compressor head, the

Defrost. thermistor circuit detects the defrosting operation temperature.

● A thermistor is a negative resistor element which has the characteristics that the higher (lower) the

temperature, the lower (higher) the resistance.

● When the compressor is heated, the resistance of the Over heat thermistor becomes low and voltage at

62

of microcomputer is increased.

● Microcomputer compares the voltage present at pin

62

with the internal set value, if it is exceeded the

set value microcomputer judges that the compressor is overheated and stops operation.

● When frost forms on the outdoor heat exchanger, the temperature at the exchanger drops abruptly.

63

Therefore the resistance of the Defrost. thermistor becomes high and the voltage at pin

of microcomputer drops. If this voltage becomes lower than the set value stored inside, the microcomputer starts defrosting control.

● During defrosting operation the microcomputer transfers the defrosting condition command to the indoor

microcomputer via the circuit interface.

● The microcomputer always reads the outdoor temperature via a thermistor (microcomputer pin

64

), and transfers it to the indoor unit, thus controlling the compressor rotation speed according to the value set at the EEPROM in the indoor unit, and switching the operation status (outdoor fan on/off, etc.) in the dry mode.

The following shows the typical values of outdoor temperature in relation to the voltage:

When the thermistor is open, in open status, or is disconnected, microcomputer pins when the thermistor is shorted, they are approx. 5 V, and LD301 blinks seven times.

However, an error is detected only when the OH thermistor is shorted; in such a case, the blinking mode is entered 12 minutes after the compressor starts operation.

0274E Pg 57-88(RAI-50NH5) 19/10/05, 3:35 PM85

Table 9-1

Outdoor temperature (°C)

Microcomputer pin

5

voltage (V)

– 85 –

-10

1.1901.69102.23

20

2.75

30

3.22403.62

62

– 64 are approx. 0V;

10. Reset Circuit

Main

HIC

P. W . B

12V

5V

Microcomputer

C107

0V

R284

R286

62

+

JW10

R292

C226

R285

0V

2

3

IC5 (1/2)

C225

R288

8

C215

–

1

+

R289

R252

C204

0V0V

48

RESET

Fig. 10-1

● The reset circuit initializes the microcomputer program when Power is “ON” or “OFF”.

● Low voltage at pin

● Fig. 10-1 shows the reset circuit and Fig. 10-2 shows waveform at each point when power is turned on

48

resets the microcomputer, and HI activates the microcomputer.

and off.

● When power is turned on, 12V line and 5V line voltages rise and 12V line voltage reaches 10.9V and

48

reset voltage input to pin

● Reset voltage will be hold “Hi” until the 12V line voltage drops to 9.90V even though the power shuts down.

of microcomputer is set to Hi.

12

6

Voltage (V)

Power is ON

0

12

6

Voltage (V)

Power is OFF

0

12V line

5V line

Reset voltage

Time

12V line

5V line

Reset voltage

Time

Fig. 10-2

– 86 –

0274E Pg 57-88(RAI-50NH5) 19/10/05, 3:35 PM86

11. Outdoor DC Fan Motor control circuit.

System power module

PQ102

FM-15V

C103

5V

0V

14

23

R114

R106

Main P.W.B

R115

+

C106

ZD101

R105

R104

R103

FM-15V

Q101

D101

R101

FM-0V

Ap 7V

33.3KHz

5V

T/2

R102

5V

t

T

+++

Smoothing Capacitor

123 4 5321

CN12

321

2A-FUSE

C101

R107

FM-0V

1

2

3

4

5

6

7

R108

0V

Fig. 11-1

U

V

W

RC Filter

0V

Vcc

PWM control voltage

FG Pulse

CN6

C104

D105

0V

61

60

59

Power supply for DC fan motor from smoothing capacitor in system power module

ONE CHIP DRIVER IC

BOARD

DC Fan motor with control board

12V

8

–

1

+

Q201

R298

0V

HIC

R283

R242

0V

C219

VSD

C208

0V

IC4

2

3

+

R246

0V

C209

R243

R244

R297

Microcomputer

65

75

FM–60˚ el

15

FG Pulse input

Motor coil

● This model uses DC Fan Motor which has a controller circuit in the Motor.

● This DC Fan Motor will rotate by control voltage apply to Vsp input. (Voltage range: 1.7 to 7V DC)

Vsp high : Faster ; Vsp low : slower ; Vsp lower than 1.7V : stop

● Motor will output FG pulse by following this motor revolution.

● Outdoor Microprocessor will output PWM control signal from FMCHOP terminal by following the instruction

from indoor Microprocessor.

● This PWM control signal will convert to Vsp voltage by smoothing circuit (Q101 & RC filter)

● Fan motor will start to rotate when Vsp was proceeding over than 1.7V, and generate FG pulse by rotation

speed.

● FG pulse will feed back to Outdoor Microprocessor through PQ102.

● PQ102 is the isolator between Microprocessor circuit and DC Fan Motor circuit, which has to match the Fan

Motor revolution with instructed revolution. Such as...

FG feedback: Faster – Instruction: Slower ... Decrease pulse width FG feedback: Slower – Instruction: Faster ... Increase pulse width

● FG pulse is also used for Fan Motor failure detection

● Microprocessor will monitor FG pulse 30 seconds after start the fan motor. If there is no signal detected, it

will consider that the Fan Motor was malfunction and stop the operation. In this case, LD302 on control PWB will blink 12 times. (Fan Motor lock detected)

● R107 and IC4 are used for Fan Motor over current

– 87 –

0274E Pg 57-88(RAI-50NH5) 19/10/05, 3:35 PM87

< Reference >

● When operation stop with LD301 blinks 12 times, it may be caused by faulty DC fan motor.

● In this case, please check CN6 and CN12 connection first. It makes Fan Motor Lock also if those

connectors are in misconnection.

● DC Fan Motor has broken when 2A Fuse was burned. Please replace both DC Fan Motor and 2A Fuse

together.

● It will makes “Fan Lock Stop”when something has disturb the Fan rotation by inserting materials into

propeller fan or ice has growing inside of outdoor unit by snowing.

● It may make “Fan Lock Stop” by strong wind (ex. 17m/sec or above) against the Fan rotation. In this case,

unit will be restart again after a while.

● In case of “Fan Lock Stop” even though the DC Fan Motor is rotating correctly, the possible casue is

Fan Motor problem or PQ102 on board or control board problem. Stop after the Fan motor runs 2 minutes, Fan Motor may be broken.

< Caution >

● Please take care for the electrical shock by high voltage of DC Fan Motor power source which is common

with compressor when you are servicing this unit.

● You can not confirm the coil and wiring of Motor due to the built in control circuit in Fan Motor.

0274E Pg 57-88(RAI-50NH5) 19/10/05, 3:35 PM88

– 88 –

12. Power Factor Control Circuit

Power factor is controlled to almost 100%. (Effective use of power)

With IC in ACT module, control is performed so that input current waveform will be similar to waveform of input voltage

I (input current)

V (input voltage)

Effective

voltage

area

Invalid power area

(Even if voltage is applied. current does not flow)

input voltage

input current

Effective

voltage area

* Assuming the same current capacity (20A), power can be used about 10% effective, comparing with curent use (power factor of 90%), and maximum capacity is thereby improved.

0274E Pg 89-96(RAI-50NH5) 19/10/05, 3:36 PM89

– 89 –

SERVICE CALL Q & A

Model RAI-50NH5

COOLING MODE

Q1

The compressor has stopped suddenly during cooling operation.

DEHUMIDIFYING MODE

Q2

Q3

Sound of running water is heard from indoor unit during dehumidifying.

Compressor occasionally does not operate during dehumidifying.

HEATING MODE

Q4

The circulation stops occasionally during Heating mode.

A1

Check if the indoor heat exchanger is frosted. Wait for 3-4 minutes until it is defrosted.

A2

A3

A4

It occurs during defrosting. Wait for 5-10 minutes until the condenser is defrosted.

If the air conditioner operates in cooling mode when it is cold, the evaporator may get frosted.

Normal sound when refrigerant flows in pipe.

Compressor may not operate when room temperature is 10°C or less. It also stops when the humidity is preset humidity or less.

Q5

Q6

When the fan speed is set at HIGH or MED, the flow is actually Weak.

Heating operation stops while the temperature is preset at "30".

At the beginning of heating,

A5

the fan speed remains LOW for 30 seconds. If HIGH is selected, it switches to LOW and again to MED after additional 30 seconds.

If temperature is high in

A6

the outdoor, heating operation may stop to protect internal devices.

0274E Pg 89-96(RAI-50NH5) 19/10/05, 3:36 PM90

– 90 –

AUTO FRESH DEFROSTING

Q7

After the ON/OFF button is pressed to stop heating, the outdoor unit is still working with the OPERATION lamp lighting.

AUTO OPERATION

Q8

Fan speed does not change when fan speed selector is changed during auto operation.

NICE TEMPERATURE RESERVATION

Q9

When on-timer has been programmed, operation starts before the preset time has been reached.

Auto Fresh Defrosting is carried out : the

A7

system checks the outdoor heat exchanger and defrosts it as necessary before stopping operation.

A8

At this point fan speed is automatic.

This is because “Nice temperature reservation”

A9

function is operating. This function starts operation earlier so the preset temperature is reached at the preset time. Operation may start maximum 60 minutes before the preset time.

Q10

Q11

Does “Nice temperature reservation” function operate during dehumidifying?

Even if the same time is preset, the operation start time varies.

INFRARED REMOTE CONTROL

Q12

Q13

Q14

Timer cannot be set.

The current time display disappears soon.

The timer has been programmed, but the preset time disappears.

A10

It does not work. It works only during cooling and heating.

This is because “Nice temperature reservation”

A11

function is operating. The start time varies according to the load of room. Since load varies greatly during heating, the operation start time is corrected, so it will vary each day.

A12

Has the clock been set? Timer cannot be set unless the clock has been set.

The current time disappears

A13

in approx. 10 seconds. The time set display has priority.

A14

Is the current time past the preset time? When the preset time reaches the current time, it disappears.

When the current time is set the display flashes for approx 3 minutes.

0274E Pg 89-96(RAI-50NH5) 19/10/05, 3:36 PM91

– 91 –

OTHERS

The indoor fan varies among

Q15

high air flow, low air flow and breeze in the auto fan speed mode. (Heating operation)

Q16

Q17

Q18

Q19

Loud noise from the outdoor unit is heard when operation is started.

Noise from the outdoor unit occasionally changes.

There is a difference between the set temperature and room temperature.

Air does not flow immediately after operation is started.

A15

This is because the cool wind prevention function is operating, and does not indicate a fault.

A16

A17

A18

A19

When operation is started, the compressor rotation speed goes to maximum to increase the heating or cooling capability, so noise becomes slightly louder. This does not indicate a fault.

The compressor rotation speed changes according to the difference between the thermostat set temperature and room temperature. This does not indicate a fault.

There may be a difference between the set temperature and room temperature because of construction of room, air current, etc. Set the temperature at a comfortable for the space.

Preliminary operation is performed for one minute when the power switch on and heating or dehumidifying is set. The operation lamp blinks during this time for heating. This does not indicate a fault.

The heat exchanger temperature is sensed in the auto speed mode. When the temperature is low, the fan speed varies among high air flow, low air flow and breeze.

0274E Pg 89-96(RAI-50NH5) 19/10/05, 3:36 PM92

– 92 –

TROUBLE SHOOTING

Model RAI-50NH5

PRECAUTIONS FOR CHECKING

DANGER

1. Remember that the 0V line is biased to 155-170V in reference to the ground level.

2. Also note that it takes about 10 minutes until the voltage fall after the power switch is turned off.

Power source

L

Indoor unit electric parts

Control P. W . B.

System power module 2

a

N

+

~

ACT Module

DC35V

C

0V

D

+–+

–

(0V)

b

MAIN P.W.B.

Across a – b (0V line)....................

Across a – ground..........................

Across b (0V line)– ground............

+

–

Power module

M

Compressor motor

approx 260-360V

approx 155-170V

DANGER

When using an oscilloscope, never ground it. Don't forget that high voltages as noted above may apply to the oscilloscope.

Outdoor unit P.W.B.

Always keep your hands and metallic things away from the enclosure of the oscilloscope.

Oscilloscope

DANGER!

Don’t install

the ground

line.

0274E Pg 89-96(RAI-50NH5) 19/10/05, 3:36 PM93

– 93 –

DISCHARGE PROCEDURE AND POWER SHUT OFF METHOD FOR POWER CIRCUIT

Caution

●

Voltage of about 300-330V is charged between both ends of smoothing capacitors

WARNING

1. Turn OFF the Power supply to the outdoor unit.

2. After power is turned off, wait for 10 minutes or more. Then, remove electrical parts cover and apply soldering iron of 30 to 75W for 15 seconds or more to P2 and N1 terminals on system power module, in order to discharge voltage in smoothing capacitor.

3. Remove receptable of red/gray lead wire connected to system power module from diode stack before performing operation chech of each circuit.

●

During continuity check for each part of circuit in indoor unit electrical parts, disconnect red/gray lead wire connected from diode stack to system power module (SPM2) to prevent secondary trouble. (Be sure to discharge smoothing capacitor)

System power module

RAC-50NH5

SPM2

P1

N1

Smoothing capacitors

Soldering iron

Do not use a soldering iron with transformer: If one is used, thermal fuse inside transformer will be blown

As shown above, apply soldering iron to metal parts (receptable) inside the sleeve corresponding to P1 and N1 terminals of system power module: Do this with smoothing capacitors kept connected. By removing red/ gray lead wire from diode stack, power supply can be shut off. (corresponding to + and – terminals of system power module)

0274E Pg 89-96(RAI-50NH5) 19/10/05, 3:36 PM94

– 94 –

CHECKING THE INDOOR/OUTDOOR UNIT ELECTRICAL PARTS AND REFRIGERATING CYCLE

Model RAI-50NH5

Timer lamp

Does the timer lamp on the indoor unit blink?

No

See Troubleshooting when the timer lamp blinks .

Remove the terminal cover and check the voltage between terminal (C) and terminal (D)

Is approx. DC 33 to 37V being generated? Is the polarity correct?

Does the operation lamp on the indoor unit start to light or blink?

Yes

Is the compressor in the outdoor unit operating?

Yes No

Remove the outdoor unit cover and electrical parts cover, and check self-diagnosis lamp LD301

CN17

022527

IC3

P. W. B

Service switch

Self diagnosis lamps (LD303, 302, 301)

Does LD301 blink one time ? * Repeats 0.25-second on and 2-second off.

No

Check to see whether the Fcable is connected incorrectly or disconnected

Normal

Yes

See Out door unit self-diagnosis lamp lighting mode .

Check the refrigerating cycle.

0274E Pg 89-96(RAI-50NH5) 19/10/05, 3:36 PM95

Blinking other than

One-time blinking

one time

Press the service switch for 1 sec. Does the compressor operate? (After checking, be sure to press the service switch to stop the operation).

Check the outdoor electrical parts.

Yes

No

Check the indoor electrical parts.

– 95 –

TROUBLESHOOTING WHEN TIMER LAMP BLINKS. Model RAI-50NH5 Perform troubleshooting according to the number of times the indoor timer lamp and outdoor LD301 blink.

SELF-DIAGNOSIS LIGHTING MODE Model: RAI-50NH5

No. Timer indicator flashing mode Reason for display Section of estimated fault

Four-way valve faulty

The room heat exchange

1

5 sec.

– ––––––– Once

temperature is low during heating, or it is high during cooling.

(1) Four-way valve faulty. (2) Disconnection in heat exchange

thermistor (only during heating)

Outdoor unit forced operation

2

3

4

5

6

7

5 sec.

– –––––– Twice

5 sec.

– ––––– 3 times

5 sec.

–– 4 times

–– 6 times

–– 7 times

–– 9 times

The outdoor unit is in forced operation or undergoing balancing after forced operation.

Indoor/outdoor interface faulty

The interface signal from the outdoor unit has been interrupted.

Outdoor electrical assembly defective.

Abnormal water level detection

All stop when the float switch has been activated.

Drain pump forced operation.

When the knob of drain pump test switch at Indoor P.W.B main slide to ‘test’ position.

Room thermistor or heat exchanger thermistor is faulty

When room thermistor or heat exchanger thermistor is opened circuit or short circuit.

Service SW in outdoor electrical parts turned ON.

(1) Indoor interface circuit (2) Outdoor interface circuit

Please check at the outdoor electrical led lamp blinking (LD301) and refer to self diagnosis lighting mode for outdoor unit.

(1) Drain stopped up (2) Drain pump (3) Float switch

(1) Indoor P.W.B. Main.

(1) Room thermistor (2) Heat exchanger thermistor

8

9

1

5 sec.

–– 10 times

–– 13 times

DC fan motor overcurrent detection

Overcurrent in indoor DC fan motor has been detected.

IC401 data reading fault

There was error in the data read from IC401

(1) Indoor fan locked (2) Indoor fan motor (3) Indoor P.W.B. Main

IC401 faulty

( –– Lights for 0.5 sec. at interval of 0.5 sec..)

(1) If the interface circuit is faulty when power is supplied, the self-diagnosis display will not be displayed.

(2) If the indoor unit does not operate at all, check to see if the F-cable is connected or disconnected.

(3) To check operation again when the timer lamp is blinking, you can use the remote control for operation

(except for mode mark

1).

0274E Pg 89-96(RAI-50NH5) 19/10/05, 3:36 PM96

– 96 –

SELF-DIAGNOSIS LIGHTING MODE

MODEL: RAI-50NH5

0274E Pg 97-118(RAI-50NH5) 19/10/05, 3:37 PM97

– 97 –

CHECKING INDOOR UNIT ELECTRICAL PARTS

1. Power does not come on (no operation)

No No Is DC 35V being generated between terminals C and D on the terminal board?

Is AC 220-240V AC being generated between terminals L and N on the outdoor unit terminal board?

Yes

Is DC 35V being generated between terminals C and D on the outdoor unit terminal board?

Check AC outlet and breaker, and repair any defective part.

Yes

Check the indoor/outdoor unit connection cable, and correct any defective section (wrong connection, incomplete insertion reversed).

Are control voltages (12V, 5V) being generated normally?

Yes

Do the air deflectors perform initial operation when the power supply is turned on and off?

No

Is the microcomputer reset input (pin 7 ) Hi ?

Yes

Is the microcomputer clock signal 10MHz at pin generated normally?

10 11

being

Yes

No

Yes

No

Check the outdoor unit power circuit, and repair the defective section.

Check according to the proper method for checking the power circuit.

Check the indication P.W.B. connection cord and light receiving unit.

Check the reset circuit, and repair any defective section.

Replace the microcomputer and oscillator.

Replace the P.W.B Main

Perform final operation check.

– 98 –

0274E Pg 97-118(RAI-50NH5) 19/10/05, 3:37 PM98

2. Outdoor unit does not operate (but receives remote infrared signal)

0274E Pg 97-118(RAI-50NH5) 19/10/05, 3:37 PM99

– 99 –

3. Only indoor fan does not operate (other is normal)

Is approx 20 V DC generated between pins 2 (blue) and 4 (red) of CN 10 when operated at high fan speed during cooling?

No

Are pulses of approx. 33 Vp-p generated at the collectors of Q901 in the fan operation mode? Are collectors of Q903 approx. O V?

Yes

Are microcomputer fan PWM outputs (micro computer pins 24)“Hi” or are pulses output in the fan operation mode?

No

Yes

Is 5 V DC generated between pins 2 (blue) and 1 (yellow) of CN10?

No

Is there 1 or less between L901 and L902?

No

Yes

Perform final operation check.

4. Indoor fan speed does not change (other is normal)

Has the fan been stopped by

Yes Yes

remote control?

No

Are microcomputer fan PWM outputs micro computer pins

No

Are the collectors of Q903 approx OV?

No

54

“Hi”?

Yes

Replace indoor fan motor.

Check disconnection, etc of lead wires.

Yes

Replace Q901.

Replace L901.

Replace Q903.

Replace micro computer.

Yes

Replace Q903.

Replace Q901.

Perform final operation check.

5. Air deflector does not move (other is normal)

Is pulse signal output to micro computer pins %~™ with air deflector set to auto during cooling?

Yes

Is there a voltage higher than 15V across C114 (12 V line)?

No

Yes

Perform final operation check.

Replace micro computer.

Replace the air deflector motor.Replace IC111.

0274E Pg 97-118(RAI-50NH5) 19/10/05, 3:37 PM100

– 100 –

6. All systems stop from several seconds to several minutes after operation is started (all indicators are also off)

Set to the "Hi" fan mode.

The operation lamp lights once and goes out in 5-10 seconds.

Yes

Disconnect, CN10 and set to the fan mode again.

The operation lamp lights once and goes out in 5-10 seconds.

No

Can the indoor fan be lightly turned by hand? (Set the power switch to "off" to check.)

Yes

Replace the indoor fan motor.

Yes

No

Check to see if shorting, etc. has occurred in the P.W.B. pattern.

Check to see if the indoor fan is touching the chassis, etc. If it does, repair.

0274E Pg 97-118(RAI-50NH5) 19/10/05, 3:37 PM101

– 101 –

CHECKING THE REMOTE CONTROLLER

0274E Pg 97-118(RAI-50NH5) 19/10/05, 3:37 PM102

– 102 –

CHECKING THE OUTDOOR UNIT ELECTRICAL PARTS

MODEL RAI-50NH5

Check to see whether the

connected C and D cable

Replace any defective parts.

If the 25A fuse has blown, be aware

that other parts may also be

defective (mainly, varistor 2, diode

stack, smoothing capacitors, system

power module, etc.).

No

correctly? If reversed, correct the

If the 3A fuse has blown, the

switching transformer (T1),

R906, etc. may also be

cable connection.

Replace any defective parts.

Yes

No

Is the switching power circuit OK?

Has the 3A fuse blown?

No

defective.

()

See the self-diagnosis lamp

lighting mode.

Ye s

Is AC220-240V being

supplied to terminal L and N?

[No operation or abnormal operation]

0274E Pg 97-118(RAI-50NH5) 19/10/05, 3:37 PM103

Is the 25A fuse normal?

Yes

See the description on

power circuit for details.

Is the power circuit normal?

Is 5V being generated

between Pin 4 (0V) and pin

3 (5V) at CN 18 (test pin)?

– 103 –

Yes

”.

Operate the outdoor unit

according to the instruction

“How to operate the outdoor

unit independently

How did the self-diagnosis

lamp (LD301) light?

There is a defective section between the

12V output of switching power supply on

the main P.W.B. and interface relay (also,

D907 and C910 may be defective.

check for contact with solder, etc.).

Repalce the interface relay.

No

Yes

Is DC 35V being output at

terminals C and D? (Normally,

DC 33-38.5V is output.)

No

Yes

Is DC 12V being supplied across

Is DC 35V being output across R914?

the control side (coil terminal) of

Yes

interface relay?

Coil terminal

Interface relay

Yes

No

Is a voltage (at least 10V) being

generated between the contact

terminals of interface relay?

Check the interface curcuit.

Contact terminal

0274E Pg 97-118(RAI-50NH5) 19/10/05, 3:37 PM104

LD301 blinks 9 time.

Communication error.

– 104 –

Ye s N o

No

Ye s

No

Check continuity of pattern and

lead wires according to the

P.W.B. and schematic diagrams.

Replace the power module.

Replace any defective parts.

Connect the thermistor.

”.

“forgetting

Check continuity of pattern and

lead wires according to the

P.W.B. and schematic diagrams.

Replace parts in the

Replace the thermistor.

thermistor circuit.

to connect after servicing

Is the power module normal?

Is the drive circuit normal?

❈ The problem may be

Is the thermistor connector

disconnected?

Is the continuity of thermistor normal?

Is the thermistor circuit normal?

Thermistor abnormal.

LD301 blinks 8 time.

Acceleration defect.

LD301 blinks 7 time.

– 105 –

0274E Pg 97-118(RAI-50NH5) 19/10/05, 3:37 PM105

Replace parts in the

thermistor circuit.

Check continuity of new parts.

Replace system power

module or defective parts.

Check continuity of pattern and

lead wires according to the

Replace the system power

module.

Replace any defective

P.W.B. and schematic diagrams.

parts.

No

Is the thermistor circuit normal?

No

Are R503, R541, R542, R549

and peripheral circuits of

system power module normal?

No

normal?

Ye s

Is the drive circuit normal?

Ye s

Replace the main P.W.B.

Is the system power module

LD301 blinks 6 time.

The temperature at the

OH thermistor rises.

0274E Pg 97-118(RAI-50NH5) 19/10/05, 3:37 PM106

LD301 blinks 5 time.

Overload lower limit cut.

– 106 –

LD301 blinks 4 time.

Failure of switching.

LD301 blinks 3 time.

Abnormal low speed.

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POWER CIRCUIT

Phenomenon 1 <Rotation speed does not increase>

Is the DC voltage at least 350V?

Ye s

Is the OVL lamp lit? If the lamp is lit, it does not indicate fault, but the unit is overload status.

Overvoltage defect: system power module faulty (15-times blinking)

No

Recheck cord, etc. of the system power module. If they are disconnected, connect them securely.

If abnormality continues, replace the system power module.

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CHECKING THE REFRIGERATING CYCLE

(JUDGING BETWEEN GAS LEAKAGE AND COMPRESSOR DEFECTIVE)

1. Troubleshooting procedure (No operation, No heating, No cooling)

Connect U,V,W phase leads to the power module again and operate the air conditioner.

Is the self-diagnosis lamp mode as shown on the right?

YES

Stop to operate and check the gas pressure in balancing mode.

Normal (0.39-0.98 MPaG) (4-10 kg/cm

2

G)

Lighting mode

Selfdiagnosis lamp

LD301

Time until the

lamp lights

Possible

malfunctioning

part

Blinks

2 times

3 times

4 times

Approx. 10 seconds

Compressor

Blinking off

5 times

Approx. 10 seconds

Blinks

6 times

Within Approx. 30 seconds

Gas leakage

Checking the system power module

Blinks 8times

Approx. 10 seconds

Compressor

Gas leaking (less than 4kg/cm (less than 0.39 MPaG)

Gas leaks. Repair and seal refrigerant.

2

G)

The compressor is defective. Replace it and seal refrigerant.

Perform a final check of operation.

When the self-diagnosis lamp lights in the same condition as above.

If the compressor checker for an inverter type air conditioner is

( )

available, re-check using it.

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HOW TO CHECK SYSTEM POWER MODULE

Checking system power module using tester

Set tester to resistance range (X 100) If indicator does not swing in the following conductivity check, the system power module is normal. (In case of digital tester, since built-in battery is set in reverse direction, + and – terminals are reversed.)

CAUTION

If inner circuit of system power module is disconnected (open), the indicator of tester will not swing and this may assumed as normal. In this case, if indicator swings when + and – terminals are connected in reverse of diagram below, it is normal. Furthermore, compare how indicator swings at U, V and W phases. If indicator swings the same way at each point, it is normal.

– +

+–

P1 P2 U

L2 L1

N1

+

–

+

WV

+

– +

+

P1 P2 U

L2 L1

N1

+

–

WV

–

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Hitachi RAI-50NH5, RAC-50NH5 Service Manual

Specifications and Main Features

Frequently Asked Questions

User Manual