Hitachi RAC-25CNH11, RAS-25CNH11 Service Manual

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Page 1

NO. 0164E

SERVICE MANUAL

TECHNICAL INFORMATION

FOR SERVICE PERSONNEL ONLY

SPECIFICATIONS

CONTENTS

SPECIFICATIONS -------------------------------------------------------------- 4 SAFETY PRECAUTION ------------------------------------------------------ 6 HOW TO USE -------------------------------------------------------------------8 CONSTRUCTION AND DIMENSIONAL DIAGRAM ---------------- 29 MAIN PARTS COMPONENT --------------------------------------------- 30 WIRING DIAGRAM ----------------------------------------------------------- 33 CIRCUIT DIAGRAM ---------------------------------------------------------- 35 BLOCK DIAGRAM ------------------------------------------------------------ 39 BASIC MODE ------------------------------------------------------------------ 41 AUTO SWING FUNCTION ------------------------------------------------- 54 DESCRIPTION OF MAIN CIRCUIT OPERATION ------------------ 55 REFRIGERATING CYCLE DIAGRAM ---------------------------------- 86 SERVICE CALL Q & A ----------------------------------------------------- 87 TROUBLE SHOOTING ------------------------------------------------------ 91 PARTS LIST AND DIAGRAM ------------------------------------------- 113

RAS-25CNH11 RAC-25CNH11

REFER TO THE FOUNDA TION MANUAL

INDOOR UNIT

RAS-25CNH11

OUTDOOR UNIT

RAC-25CNH11

WALL TYPE

SPECIFICATIONS AND PARTS ARE SUBJECT TO CHANGE FOR IMPROVEMENT

ROOM AIR CONDITIONER

INDOOR UNIT + OUTDOOR UNIT

JANUARY 2003

H.A.P.M.

TYPE

MODEL

1ø 220V 50HzPOWER SOURCE

910 (190 ` 1,150) [COOL] / 1,250 (160 ` 1,350) [HEAT]TOTAL INPUT

4.20 ` 3.85 [COOL] / 5.75 ` 5.25 [HEAT]TOTAL AMPERES (RATED / MAX.)

COOLING CAPACITY

HEATING CAPACITY

DIMENSIONS

NET WEIGHT

(W)

(A)

(kW)

(B.T.U ./h)

(kW)

(B.T.U ./h)

H D

(kg)

(mm)

2.50 (0.90 ` 2.80)

8,870 (3,070 ` 9,550)

3.60 (0.90 ` 4.00)

12,280 (3,070 ` 13,650) 744 248 168

5.5

700 570 210

RAS-25CNH11

RAC-25CNH11

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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.

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 or more as measured by a 500V 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.

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.

First, I must disconnect the power cord plug

from the power outlet.

DANGER

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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).

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.

Fig. 2. Body Earth

Body earth (Elimik conductive band)

Clip for connection with a grounding wire

A conductive polyvinyl bag

Conductive sponge

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

Bare copper wire (for body earth)

Working table

Resistor of 1 M (1/2W)

Earth wire

Fig. 3. Grounding of the working table

Screw stop at the screwed part using a rag plate

Soldering iron

Grounding wire

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.

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

Staple

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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. If the room air conditioner is stopped by setting the temperature or mis-operation, and then re-started in a moment, cooling 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.

4. This room air conditioner should not be used at the cooling operation when the outside temperature is below 20°C.

5. When the operation knob is set to “COOL” from another position, IC delay circuit functions and stops the compressor for the first 3 minutes, which is not an abnormal phenomenon.

CAUTION

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RAS-25CNH11 RAC-25CNH11

MODEL

FAN MOTOR

FAN MOTOR CAPACITOR

FAN MOTOR PROTECTOR

COMPRESSOR

COMPRESSOR MOTOR CAPACITOR

OVERLOAD PROTECTOR

OVERHEAT PROTECTOR

FUSE

POWER RELAY, STICK RELAY

POWER SWITCH

TEMPORARY SWITCH

SERVICE SWITCH

TRANSFORMER

VARISTOR

NOISE SUPPRESSOR

REMOTE CONTROL SWITCH (LIQUID CRYSTAL)

THERMOSTAT

FUSE CAPACITY

SPECIFICATIONS

---------- ❈ 690g

UNIT

PIPES

❈ 690g for piping set of 5~8m.

REFRIGERANT CHARGING VOLUME

(Refrigerant 22)

WITHOUT REFRIGERANT BECAUSE COUPLING IS FLARE TYPE. P - 105 VK1 (5m), P - 108 VK1 (8m)

20 W

NO GR20DR2F

----------

YES

G4A

YES

416NR

YES

YES (IC)

----------

16A INRUSH

WITHSTAND TYPE

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above 100mm

❈ above 300mm

above 200mm

❈ above 100mm

Maximum pipe length 8m

❈ give clearance as wide as possible

above 50mm

above 100mm

about 0.45m

above 300mm

must not bend

above 100mm

Used in horizontal piping

above 50mm when installed on the ceiling of balcony

above 200mm

2,500mm or more

Plug

The Length of Indoor Unit Connecting

Cord

Figure showing the Installation of Indoor and Outdoor Unit.

about 1.6m

about

0.9m

● 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).

The connection of insulated drain hose.

Please use insulated drain hose for the indoor piping (commercial product).

inner diameter ø 16mm

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

Be sure to completely seal any gap with putty.

Direction of Piping

Dimension of Mounting Stand

of the outdoor unit

500

100

225

mounting stand

(unit : mm)

There are 3 directions allowed, namely, horizontally perpendicular to the unit, vertically down from right, horizontally out from right. Don’t form the piping downward at the left of the unit.

Cut away shaded portion, and finish the edge of the opening so that there is no burr.

Connection

Horizontally perpendicular to the unit

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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.

●

Please keep this manual after reading.

WARNING

PRECAUTIONS DURING INSTALLATION

●

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

●

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.

CAUTION

PRECAUTIONS DURING SHIFTING OR MAINTENANCE

PRECAUTIONS DURING OPERATION

●

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

A R N

●

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

●

Do not put objects like thin rods into the panel of blower and suction side because the high-speed fan inside may cause danger.

●

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

●

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

Make sure to connect earth line.

Indicates the instructions that must be followed.

The sign in the figure indicates prohibition.

A R N

I N G

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PRECAUTIONS DURING OPERATION

●

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.

●

Do not place plants directly under the air flow as it is bad for the plants.

●

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.

●

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.

●

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

●

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.

C A U

I O N

●

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

●

Do not put water container (like vase) on the indoor unit to avoid water dripping into the unit. Dripping water will damage the insulator inside the unit and causes short-circuit.

●

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.

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INDOOR UNIT

NAMES AND FUNCTIONS OF EACH PART

Air filter

To prevent dust from coming into the indoor unit. (Refer page 25)

Indoor unit indicators

Light indicator showing the operating condition. (Refer page 9)

Front panel (Air Inlet)

Horizontal deflector

●

Vertical deflector

(Air Outlet)

(Refer page 20)

Remote controller

Send out operation signal to the indoor unit. So as to operate the whole unit. (Refer page 10)

OUTDOOR UNIT

DRAIN PIPE

Condensed water drain to outside.

CONNECTING CORD

AIR INLET (BACK, LEFT SIDE)

AIR OUTLET

WIDTH (mm)

745 700

MODEL RAS-25CNH11 RAC-25CNH11

HEIGHT (mm)

248 570

DEPTH (mm)

175 210

MODEL NAME AND DIMENSIONS

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INDOOR UNIT INDICATORS

TEMPORARY SWITCH

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

● By setting 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 is done in automatic mode.

OPERATION INDICATOR

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.

TIMER LAMP

This lamp lights when the timer is working.

SIGNAL RECEIVER

There will be a beep sound when this receiver receives signal from remote controller.

POWER SWITCH

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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

RESET

NAMES AND FUNCTIONS OF REMOTE CONTROL UNIT

REMOTE CONTROLLER

This controls the operation of the indoor unit. The range of control is about 7 meters. If indoor lighting is controlled electronically, the range of control may be shorter. This unit can be fixed on a wall using the fixture provided. Before fixing it, make sure the indoor unit can be controlled from the remote controller.

● Signal emitting window/transmission sign

Point this window toward the indoor unit when controlling it. 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) (during the (FAN) mode, from HI to MED to LOW).

● 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.

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AUTOMATIC OPERATION

The device will automatically determine the mode of operation, HEAT, COOL or DEHUMIDIFY depending on the initial room temperature. The selected mode of operation will not change when the room temperature varies.

■ As the settings are stored in memory in the remote controller, you only have to press the (START/STOP) button next time.

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 initial room temperature.

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

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

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

● 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.

START

STOP

°C

RESET

Over 27°C COOL

23~27°C

Under 23°C HEAT

Temperature settingFunction

27°C

23°C

Slightly lower than the room temperature

LOW

FAN SPEED

HI at start, MED or LOW after the preset temperature is reached

DEHUMIDIFY

Initial room temperature (approx.)

■ Condition of Automatic Operation

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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.

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

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) : Quiet. (LOW) : More quiet.

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

The range of 18-22°C is recommended as the room temperature for heating. If the temperature setting is 20°C, the room temperature will be controlled at around 20°C.

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.

■ As the settings are stored in memory in the remote controller, you only have to press the (START/STOP) button next time.

START

STOP

RESET

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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.

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

■ Dehumidifying Function

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.

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

have to press the

(START/STOP) button next time.

START

STOP

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.

RESET

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RESET

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 (COOL).

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 automatically when the preset temperature has been reached.

(HI) : E conomical as the room will become cool

quickly. (MED) : Quiet. (LOW) : More quiet.

Press the

(START/STOP) button. Cooling operation starts 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.

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

The range of 25-28°C is recommended as the room temperature for cooling. If the temperature setting is 27°C, the room temperature will be controlled at around 27°C.

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

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

only have to press the

(START/STOP) button next time.

START

STOP

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* Note • In the fan operation mode, only display of FAN SPEED

setting will change by pressing FAN SPEED button; the actual fan speed cannot be changed directly from HI to LOW mode.

FAN SPEED (AUTO)

.....

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

For the 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.

● 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.

For the cooling operation

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 (FAN).

Press the (FAN SPEED) button.*

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

1 2

START

STOP

RESET

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HOW TO SET THE TIMER

ON/OFF-Timer

● 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.

Press the (ON-OFF)

button so that the (OFF) mark blinks.

OFF-Timer

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

After you change the batteries;

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.

Set the current month and

day with the TIMER control button.

Press the (OFF-TIMER)

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

Press the (ON-TIMER)

button the (ON) mark blinks on the display.

Set the turn-off time

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

Press the (ON-

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

NOTE

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

ON-Timer

Time, Day, Month

● The device will turn on

at the designated times.

TIME, DAY, MONTH (current time, day, month)

OFF TIMER

ON TIMER RESERVE CANCEL

M D

STOP

Start

Stop

Start Stop

RESET

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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.

● The time indication will disappear

automatically in 10 second.

● To check the current time setting,

press the (TIME) button twice. The setting of the current time is

now complete.

● 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.

Press the

(TIME) button.

Set the current time with the

TIMER control button.

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

Set the turn-off time with the

TIMER control button.

The setting of turn-off time is now complete.

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

Example: The device will automatically turn on earlier so that the preset temperature can be reached at 7:00 a.m. The setting of the turn-on time is now complete.

Set the turn-on time with the

TIMER control button.

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.

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.

Set the turn-on time with the

TIMER control button.

Example: The device will turn off at 10:30 p.m. and then automatically turn on earlier so that the preset temperature can be reached at 7:00 a.m. The settings of the turn-on/off times are now complete.

Press the (TIME) button again.

The time indication starts lighting instead of flashing.

PM PM

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HOW TO SET THE SLEEP TIMER

Set the ON-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

Sleep timer

Indication

1 hour 2 hours 3 hours 7 hours

Sleep timer off

44 44

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.

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

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

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

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.

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.

SLEEP

Sleep

timer

Start

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Cooling

“ ”

and

dehumidifying

“ ”

Explanation of the sleep timer

The device will control the FAN SPEED and room temperature automatically so as to be quiet and good for people’s health. You can set the sleep timer to turn off after 1, 2, 3 or 7 hours. The FAN SPEED and room temperature will be controlled as shown below.

Function Operation

The settings of room temperature and circulation are varied.

The room temperature will be controlled 2°C above the temperature and the FAN SPEED will be set to LOW setting 30 minutes after the setting of the sleep timer.

Fan

“ ”

Heating

“ ”

The room temperature will be controlled 5°C below the temperature and the FAN SPEED will be set to LOW setting 30 minutes after the setting of the sleep timer.

Operation with the sleep timer

Sleep timer set

30 minutes later

1 hour later

3 hours later

7 hours later

2 hours later

5°C

● If date or current time is not set, sleep timer can not be set.

● If you set the sleep timer after the off-, on/off- or off/on-timer has been set, the sleep timer

becomes effective instead of the off-, on/off- or off/on-timer set earlier.

● You can not set other timer during sleep timer operation.

● After sleep timer time is up and when press sleep button again, the sleep timer will be set as

last setting.

● Sleep timer effective only once.

NOTE

Sleep timer set

30 minutes later

3 hours later

7 hours later

2 hours later

6 hours later

2°C

Page 22

– 20 –

ADJUSTING THE AIR DEFLECTOR

Adjustment of the conditioned air to the left and right. Hold the vertical air deflector as shown in the figure and adjust

the conditioned air to the left and right.

● 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.

● When the operation is stopped, the horizontal air deflector

moves and stops at the position where the air outlet closes.

When cooling dehumidifying

When heating

CAUTION

● In “Cooling” operation, do not keep the horizontal air

deflector swinging for a long time. Some dew may form on the horizontal air deflector and some dew drops may fall from it.

RESET

Adjustment of the conditioned air in the upward and downward directions.

The horizontal air deflector is automatically set to the proper angle suitable for each operation. The deflector can be swung up and down continuously and also set to the desired angle using the “ (AUTO SWING)” button.

Page 23

– 21 –

HOW TO EXCHANGE THE BATTERIES IN THE REMOTE CONTROLLER

Remove the cover as shown in the figure and take out the old batteries.

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

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.

CAUTION

Push and pull to the direction of arrow

TEMPORARY SWITCH

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

● By setting 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 is done in automatic mode.

POWER SWITCH

TEMPORARY SWITCH

Page 24

– 22 –

Suitable Room Temperature Install curtain or blinds

Ventilation Effective Usage Of Timer

Do Not Forget To Clean The Air Filter

Please Adjust Suitable Temperature

For Baby And Children

Warning

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

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

At night, please use the “OFF or ON timer 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.

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.

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.

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.

THE IDEAL WAYS OF OPERATION

Page 25

– 23 –

FOR USER’S INFORMATION

The Air Conditioner And The Heat Source In The Room

Not Operating For A Long Time

When Lightning Occurs

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.

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.

Warning

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

OFF

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.

Inverter-type fluorescent lamp.

To prevent interference, place at least 1m away.

Page 26

– 24 –

ATTACHING THE AIR CLEANSING AND DEODORIZING FILTERS

Before installation, be sure to stop the operation by using the remote controller.

Open the front panel.

● Pull up the front panel holding it at both sides by both

hands.

Remove the filter.

● Push the filter upward to release the claws

and pull out the filter.

Attaching the air cleansing and deodorizing filters to the filter.

● Attach the air cleansing and deodorizing filters to the

frame by gently compress its both sides and release after insertion into filter frame.

NOTE

● In case of removing the air cleansing and deodorizing filters, please follow the above procedures.

● The cooling capacity is slightly weakened and the cooling speed becomes slower when the air cleansing

and deodorizing filters are used. So, set the fan speed to "HIGH" when using it in this condition.

● Air cleansing and deodorizing filters are washable and reusable up to 20 times by using vacuum cleaner

or water rinse under running tap water. Type number for this air cleansing filter is <SPX-CFH5>.

● Do not operate the air conditioner without filter. Dust may enter the air conditioner and fault may occur.

Attach the filter.

● Attach the filter by ensuring that the surface written

“FRONT” is facing front.

● After attaching the filter, push the front panel at three

arrow portions as shown in figure and close it.

Claws (8 places)

Make sure the “FRONT” is facing back side

Claws

Front cover

Front panel

Air filter

CAUTION

Do not bend the air cleansing and deodorizing filter as it may cause damage to the structure.

Frame

Page 27

– 25 –

INSTALLATION METHOD

REMOVING METHOD

Air filter

Air cleansing and deodorizing filter

MAINTENANCE

Before the cleaning, stop operation and disconnect the power supply.

1. AIR FILTER

Clean the air filter, as it removes dust inside the room. In case the air filter is full of dust, the air flow will decrease and the cooling capacity will be reduced. Further, noise may occur. Be sure to clean the filter following the procedure below.

NOTE:

● Air cleansing and deodorizing filter should be cleaned every month or sooner if noticeable loading

occurs. When used overtime, it may loose its deodorizing function. For maximum performance, it is recommended to replace it every 3-6 months depending on application requirements.

PROCEDURE

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 use detergent on the air cleansing and deodorizing filter as some detergent may deteriorate

the filter electrostatic performance.

Open the front panel and remove the filter

● Gently lift and remove the air cleansing and

deodorizing filters from the air filter frame.

● Re-insert the air cleansing and deodorizing

filters to the filter frame. Set the filter with "FRONT" mark facing front, and slot them into the original state.

● After attaching the filter, push the front panel

at three arrow portions as shown in figure and close it.

● Vacuum dust from the air filter and air

cleansing and deodorizing filters using vacuum cleaner. If there is too much dust, rinse under running tap water and gently brush it with soft bristle brush. Allow filters to dry in shade.

Page 28

– 26 –

2. Washable Front Panel

● Remove the front panel and wash with clean

water. Wash it with a soft sponge. After using neutral detergent, wash thoroughly with clean water.

● When front panel is not removed, wipe it with

a soft dry cloth. Wipe the remote controller thoroughly with a soft dry cloth.

● Wipe the water thoroughly.

If water remains at indicators or signal receiver of indoor unit, it causes trouble.

Method of removing the front panel. Be sure to hold the front panel with both hands to detach and attach it.

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.

Removing the Front Panel

Arm

● When the front panel is fully opened with

both hands, push the right arm to the inside to release it, and while closing the front panel slightly, put it out forward.

Attaching the Front Panel

● Move the projections of the left and right

arms into the Flanges in the unit and securely insert them into the holes.

Projection

Hole

Flange

Page 29

– 27 –

3. MAINTENANCE AT BEGINNING OF LONG OFF PERIOD

● Run the unit by setting the operation mode to

(COOL), the temperature to 32°C and the fan speed to HI for about half a day on a fine day, and dry the whole of the unit.

● Switch off the power plug.

REGULAR INSPECTION

PLEASE CHECK THE FOLLOWING POINTS BY QUALIFIED SERVICE PERSONAL EITHER EVERY HALF YEARLY OR YEARLY. CONTACT YOUR SALES AGENT OR SERVICE SHOP.

Is the earth line disconnected or broken?

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

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

Air

Blow

Cleaning and maintenance must be carried out only by qualified service personal. Before cleaning, stop operation and switch off the power supply.

CAUTION

Confirm

Page 30

– 28 –

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.

AFTER SALE SERVICE AND WARRANTY

WHEN ASKING FOR SERVICE, CHECK THE FOLLOWING POINTS.

When it does not operate

● Is the fuse all right?

● Is the voltage extremely high or low?

● Is the circuit breaker “ON”?

● Was the air filter cleaned?

● 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?

CONDITION CHECK THE FOLLOWING POINTS

Notes

● In quiet operation or stopping the operation, 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

gradually warmed as operation stops.

● 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 the air filter and the evaporator regularly must be cleaned to reduce the odor.

●

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.

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

Page 31

– 29 –

1 173

147

About 350

About 280

About 290

42.5

23.5

248

6.5559

450

744

(147)

595

120

CONSTRUCTION AND DIMENSIONAL DIAGRAM

MODEL RAS-25CNH11

MODEL RAC-25CNH11

Air outlet

Handle

Air inlet

(18)

490

Handle

Viewed from P

157

245

225

500

570

428

700

243

236 210 10

482

517

135

Air suction grill

Top air suction grill

Mounting plate

Wireless remote controller

Cabinet

Front cover

VIEWED FROM BACK (PIPE LEAD-OUT)

Discharge grill

V ertical air deflector

Horizontal air deflector

Hole on the wall for ø65 mm pipe

Line cord

Connecting cable

Narrow pipe (ø6.35)

Wide pipe (ø9.52)

Drain cap connection part

When piping is drawn horizontally, exchange the drain hose for the drain cap.

Drain Pan

Page 32

– 30 –

MAIN PARTS COMPONENT

THERMOSTAT

Thermostat Specifications

FAN MOTOR

Fan Motor Specifications

CONNECTION

20°C

(68°F)

75°C

(167°F)

TEMPERATURE °C (°F)

INDICATION

MODEL RAS-25CNH11 THERMOSTAT MODEL IC

ON 17.6 (63.7) OFF 16.6 (61.8) ON 25.6 (78.1) OFF 24.6 (76.3) ON 33.6 (92.5) OFF 32.6 (90.7)

RESISTANCE VALUE

( )

–––––––

MODEL RAS-25CNH11

RAC-25CNH11

RATED VOLTAGE DC0 – 35V

DC230V

OUTPUT 20W

20W

RED

YELLOW

BLUE

0`30V

WHITE

YELLOW

RED

–––––––

Page 33

– 31 –

MODEL RAC-25CNH11 COMPRESSOR MODEL GR20DR2F PHASE SINGLE RATED VOLTAGE AC 220 – 240 V RATED FREQUENCY 50 Hz POWER SOURCE FOR COMPRESSOR Vcc max = 360V POLE NUMBER 4

COMPRESSOR MOTOR

Compressor Motor Specifications

CONNECTION

20°C

(68°F)

75°C

(167°F)

( )

RESISTANCE VALUE

ORANGE

RED

WHITE

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.

2M = 3.21

2M = 3.90

(U)

(V)

(W)

WHITE

YELLOW

RED

Page 34

WIRING DIAGRAM

MODEL RAS-25CNH11 / RAC-25CNH11

Indoor unit

AC 220V 50HZ

TERMINAL BOARD

HEAT EXCHANGER THERMISTOR

ROOM THERMISTOR

LIGHT RECEIVING UNIT P.W.B.

WIRELESS

REMOTE CONTROL

INDOOR FAN MOTOR

STEPPING MOTOR

CONNECTING

CABLE

TERMINAL

BOARD

TEST

CN6

CN7

The marked parts are very important ones for safety.

CAUTION

Outdoor unit

BROWN BLUE

BLUE

BROWN

GREEN

YELLOW

POWER SWITCH

FUSE (76 0C)

C N 9

C N 1 0

C N 4

C N 1

C N 2

MAIN P.W.B.

GRAY

BLACK

BLUE YELLOW RED

BLACK

WHITE

BROWN

RED

(RED)

(BROWN)

(WHITE)

(BLACK)

(GREEN

YELLOW)

TERMINAL BOARD

CONNECTING

CABLE

(BLACK)

(WHITE)

(BROWN)

(RED)

BROWN

RED

GREEN

WHITE

GREEN

BLACK

WHITE

BROWN

RED

WHITE

WHITE WHITE

RED

WHITE

RED

YELLOW

RED

WHITE

BLUE

GRAY

REV-VALVE COIL

OUTDOOR FAN MOTOR

GRAY

BROWN

OUTDOOR TEMPERATURE THERMISTOR

DEFROST THERMISTOR

OVERHEAT THERMISTOR

CN4

CN5

CN6

SWITCHING POWER SUPPLY

SMOOTHING CAPACITOR 1000µF

RUSH CURRENT PROTECTION

BLUE

BROWN

BLUE

YELLOW

DIODE STACK

YELLOW YELLOW

RCI DIODE STACK

CAPACITOR

REACTOR

BLACK

GRAY

DIODE STACK

GRAY

DISCHARGE RESISTANCE

( POWER MODULE)

WHITE WHITE

YELLOW

RED RED

COMPRESSOR MOTOR

PM1

BALANCE

R807 RL1

100

FX2

R806

(50mQ)

FUSE

STICK RELAY

POWER RELAY

RL2

RL3

R805

C805

VS2

R805

L801

C806

VS1

VS3

AS1

15A FUSE

CN26 9

CN16

2A FUSE

CN25

CN24

CN2

DC FAN MOTOR CONTROL P. W. B .

(GREEN

YELLOW)

CN26

NF-COIL

MAIN P. W . B.

123

1 2 3 4

CI C2 M1 M2

ZZZ

OUTDOOR FAN MOTOR CONTROLLER

~ ~

– 33 –

Page 35

– 35 –

CIRCUIT DIAGRAM

MODEL RAS-25CNH11

Page 36

– 37 –

CIRCUIT DIAGRAM

MODEL RAC-25CNH11

Page 37

BLOCK DIAGRAM

MODEL RAS-25CNH11/RAC-25CNH11

INDOOR UNIT OUTDOOR UNIT

Power switch

Magnetic relay

Inrush current

Protection circuit

Power circuit

Outdoor DC fan motor

Power module

Indoor fan motor

Micro computer clock circuit

DC fan motor drive circuit

Indoor / Outdoor interface circuit

Temporary switch

Reset circuit

Initial setting circuit

Heat exchanger temperature thermistor

Indicating lamp

Auto sweep motor for Air deflector

Buzzer circuit

Operation. Timer. Dehumidifying.

Indoor micro computer (AX-7J03)

Outdoor micro computer (8E21)

LCD wireless

Room temperature thermistor

Wireless receive circuit

DC current signal

Rotor magnetic pole position detection circuit

Peak current cut off circuit

Overload control circuit

Voltage amplification circuit

Over heat thermistor

Defrost thermistor

Outdoor temperature thermistor

Indoor / Outdoor interface circuit

Power circuit (Indoor unit)

Power circuit

(P.W.B.)

Reversing valve coil

Clock circuit

Relay drive circuit

Reset circuit (Watch dag)

Self-diagnosis circuit

Trip signal synthesiz circuit

Upper arm drive circuit

Lower arm drive circuit

Peak current cut off

DC compressor motor

AA BB

CC DD

DC35V

– 39 –

Page 38

BASIC MODE

MODEL RAS-25CNH11

Operation mode

Fan

Basic operation of Start/Stop switch

OFF-timer

ON-timer

Timer operation

Cooling Dehumidifying Heating Auto

Operation lamp

Start / stop switch

Reserve switch

Cancel switch

Timer lamp

Timer memory

(OFF — timer in the stop mode) (Reserved time change)

(Reserved time change) (ON — timer in the operation mode)

Timer memory

Start / stop switch

Start StartStop Stop

Start / stop switch

Operation mode

Shift value

Heating

Cooling, dehumidifying

Normal Normal Cool Rhythm

SHIFTW SHIFTC SFTRZM

Table 3 Room temp. shift value

Operation mode

Label name

Heating

Table 2 Room temp. shift value

Fan speed tap

Voltage set

value

Cooling

Dehumidifying

Super Lo Lo Overload Med Hi Super Hi Lo Med Hi Super Hi Lo Med Super Lo

AFWSS AFWS AFWKAF AFWL AFWH AFWHH AFCS AFCL AFCH AFCHH AFDS AFDL AFDSS

9.8V

16.6V

19.1V

27.7V

16.0V

18.7V

20.9V

16.0V

18.7V

15.0V

Note:

1. Refer to data in Table 1 and 2 for constants shown by capital letters in Table 3.

Table 1

RAS-25CNH11

Model

Data

Required value of unit side

Source file name

Label name

MODDT (mode data file)

WMAX WSTD CMAX CSTD CKYMAX CJKMAX COYMAX WMIN CMIN DMIN SDMAX SDRPM SHIFTW SHIFTC SFTRZM YNEOF TEION TEIOF TDSFNP CLMXTP DFTIM TDF411 TDF412 TDF413 TDF421 TDF422 TDF431 SITUA SITUB SFTDSW KAFON KAFOF

5400 min

-1

4700 min

-1

4000 min

-1

4000 min

-1

2500 min

-1

2500 min

-1

2450 min

-1

1950 min

-1

1950 min

-1

1950 min

-1

2500 min

-1

2150 min

-1

1.33 ˚C 0 ˚C

2.0 ˚C

24 ˚C

5 ˚C 9 ˚C 5 ˚C

30 ˚C 40 min. 57 sec.

Above value+37 sec. Above value+ 0 sec.

60 sec.

3900 min

-1

75 sec.

0.3

5.67 ˚C

1.33 ˚C

48 ˚C

42 ˚C

– 41 –

Page 39

– 43 –

CoolingDehumidifyingHeating

Fan speed mode : AUTO

Fan speed mode : Lo

Fan speed mode : AUTO

Room temp.

Cooling preset temp.

Thermostat judgement Compressor Hi Med Lo

(Compressor is forced-stopped for 3 min.)

OFF

ON ON

Start/Stop switch Compressor Lo

32"

42.66

37.66

32.66

27.66

Compressor rotates at maximum speed during Hot dash operation or when recovered from defrosting.

Other than on left

Super Hi Hi Med Lo

Heat exchanger temp.

KAFON

KAFOF Overload

Operation mode

Auto

Med.

Basic mode of the temperature control

Fan speed mode (Indoor unit)

Cooling Dehumidifying Heating Auto

Changes to "Med" or "Lo" from "Hi" according to the room temperature.

1.Operation continues in "Hi" mode until the thermostat turns off for the 1st time. ("Super Hi" is set during Cool dash operation with the compressor rotating at maximum speed.)

2.Operates in "Lo" mode when the thermostat is OFF.

"Super Hi" mode operation is done during Cool dash operation with the compressor rotating at maximum speed, and "Hi" mode operation is done in other modes.

"Med" mode operation is done regardless of the room temperature.

"Lo" mode operation is done regardless of the room temperature.

Refer to page 45.

"Lo" mode and "Stop" mode are repeated according to the compressor operation.

Refer to page 49.

Operation mode is changed to one of "Super lo", "Lo", "Med", "Hi", "Super Hi" and "Stop" according to the room temperature, time and heat exchanger temperature. When the heat exchanger temperature becomes 18˚C or less except for the preheating operation mode, "Stop" is set. (The operation recovers at 18.66˚C)

Operation mode is changed to one of "Lo", "Med", "Hi", "Super Hi" and "Stop" according to the room temperature and time. "Super Hi" operation is done when the compressor rotates at maximum or when recovering from defrosting.

Operation mode is changed to one of "Lo", "Med" and "Stop" according to the room temperature and time.

Operation mode is changed to one of "Lo" and "Stop" according to the room temperature and time. The fan speed is controlled by the heat exchanger temperature and overload control is done as shown below.

Refer to page 51 and 53.

The following operation mode is set depending on the room temperature when the operation is started. However, in the auto cooling mode, the Cool rhythm operation starts when the room temperature becomes the preset temperature + 0.66˚C after the Dash operation is completed.

Note:

1. Refer to data in Page 41 Table 1 and 2 for each constant shown by capital letters in the diagram.

Note (1)Mode is not changed after the

operation is started.

(2)The preset temperature can be

changed within ±3˚C using the room temp. control button " " "V". For example, if the preset temperature for cooling is increased by +2˚C to change it to 29˚C, the preset temperature for heating is also changed to 25˚C. Also the operation mode selected from the room temperature at the start of operation is judged based on the changed value.

Page 40

– 45 –

Room temp.

Start

Start/stop switch

Operation lamp

Compressor rotation speed

Outdoor fan

Reversing Valve

(Heating ON mode)

Maximum

(CMAX)

1 min. 3 min.

Rated speed

(CSTD)

3000

Fixed rotation period

15 sec.

15 sec. 15 sec.

1 min.

Minimum

(CMIN)

Indoor unit fan

Thermostat judgement

Super Hi Hi Med Lo Super Lo

Stop Start

Thermostat

OFF

Stop

CLMXTP

Preset temperature for cooling (+) SHIFTC

TCMAX

Fan speed "auto" setting

Note:

(1) Conditions to start Cool dash operation are as follows. When the operation starts with the "AUTO" or "Hi" fan speed or when the fan speed is changed to "Hi" during cooling operation, if the temperature difference between the room

temperature with the compressor rotating at maximum speed and the preset temperature is ( TCMAX: refer to Table 1) or more, Cool dash will start.

(2) Conditions for releasing Cool dash operation (compressor maximum rotation speed period) are as follows.

1 Cool dash has been continued for 25 minutes. 2 The room temperature reaches the cooling preset temperature (including cooling shift value) -1˚C and then the room temperature ≥ preset temperature -0.66˚C is reached after the fixed rotation period has elapsed. 3 The thermostat is turned OFF.

(Ehen Cool dash is released by above 1, Pl control starts without operating for fixed rotation period.) (3) The thermostat OFF temperature during Cool dash operation is cooling preset temperature (including cooling shift value) +3˚C, and after the thermostat is turned OFF, Cool dash is finished and Pl control starts. (4) The minimum ON time of the compressor is 3 minutes, and minimum OFF time is also 3 minutes. (5) The compressor speed in the fixed rotation period after releasing Cool dash maximum speed is the minimum speed (CMIN). (6) The time limit to keep the maximum speed (CMAX) of the compressor in the normal cooling operation (other than Cool dash) is within 60 minutes when the room temperature is CLMXTP or less. If the room temperature is more than

CLMXTP, there is no time limit. (7) When the fan speed setting of the remote control is "Med", the maximum compressor speed is CJKMAX. (8) When the fan speed setting of the remote control is "Lo", the maximum compressor rotation speed is COZMAX. (9) When the fan speed setting of the remote control is "Hi", and both the room temperature and external temperature (data from the outdoor unit) satisfy the dewing condition shown in Table 2, the maximum compressor speed is

CKYMAX. (This control is effective only when external temperature data is provided.)

Table 1 TCMAX

Max. speed (CMAX) — Min. speed (CMIN)

Room temp. — Preset temp. (including shift)

650min

-1

750min

-1

800min

-1

850min

-1

950min

-1

1000min

-1

1050min

-1

1150min

-1

1200min

-1

1250min

-1

1350min

-1

1400min

-1

1450min

-1

1550min

-1

1600min

-1

1650min

-1

1.66˚C

2.00˚C

2.33˚C

2.66˚C

3.00˚C

3.33˚C

3.66˚C

4.00˚C

4.33˚C

4.66˚C

5.00˚C

5.33˚C

5.66˚C

6.00˚C

6.33˚C

6.66˚C

Table 2 Dewing condition judgement value

Item

Temperature

Room temp.

External temp.

Dewing condition (ON) Dewing condition (OFF) Dewing condition (ON) Dewing condition (OFF)

30˚C 32˚C 32˚C 34˚C

Note:

1. Refer to data in page 41 Table 1 for each constant shown by capital letters in the diagram.

BASIC COOLING OPERATION

Page 41

– 49 –

Dehumidifying

Cooling preset

Start/Stop Switch

Low humidity

High humidity

15 sec.

5 min. OFF/1 min. ON 6 min. OFF/1 min. ON 32 sec. 32 sec.

30 sec.

Room temperature judgement

15 sec. 15 sec. 15 sec.

Operation lamp Humidity judgement

Indoor fan

Outdoor fan

Reversing valve

Hi Med Lo Hi Med Lo

3000

SDMAX

SDRPM

Compressor

rotation speed

1 min. 1 min. 1 min. 1 min.

Thermostat judgement

temperature

Room temperature judgement

Room temperature

30 sec.

(1) 30 seconds after the operation is started, when the room temperature is (cooling preset temperature) – (1.33˚C) or less, 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, OFF for 5 minutes and ON for 1 minute (at high humidity) or OFF for 6 minutes and ON for 1 minute (at low humidity),

repeatedly according to the humidity judgement when the thermostat is turned OFF. (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 miniumu ON time and OFF time of the compressor are 3 minutes.

Note:

Cooling defrost

Thermostat OFF

Refer to the basic operation.

15 sec.

minimum 3 min.

Note: (1) Compressor stop time is 3 minutes minimum.

Compressor rotation speed

Thermostat

judgement

Indoor fan

Outdoor fan

Hi Med Lo

TEIOF

Indoor unit heat exchager temperature

TEION

1 min.

3000 min

Note:

1. Refer to data in page 41 Table 1 for each constant shown by capital letters in the diagram.

Page 42

– 47 –

Final Preset temperature

Room temp.

Minimum

5 min.

Minimum

5 min.

Minimum

5 min.

Minimum

5 min.

5 min. 5 min. 5 min. 5 min. 5 min.Minimum 5 min. Minimum 5 min.

Cooling Preset temperature (normal)

Cooling Preset temperature (rhythm)

Outdoor fan

Indoor fan

Compressor rotation

speed

COOL

RHYTHM

Thermostat judgement

Hi Med Lo

Refer to the basic operation

Thermostat OFF

1cycle

5 sec. 2.5 sec.

2.5 sec.

2.5 sec. 15 sec.5 sec.

COOL RHYTHM

Note: (1) Cool rhythm operation starts during the cooling operation in the AUTO operation mode, not during Cool dash,

and when the room temperature is the preset temperature +0.66˚C or less.

(2) In Cool rhythm operation, the temperature rising period is 10 minutes (minimum) and also temperature falling

period is 10 minutes (minimum). (3) The Cool rhythm operation is not done during Nice temperature, Sleep and Cool dash operations. (4) In Cool rhythm operation, Pl control is done and the compressor rotation speed limit is the same as in normal

operation. (5) When the thermostat is turned OFF, the shifting of the preset temperature in Cool rhythm operation is done.

Page 43

Basic heating operation

Note:

(1) Conditions for starting Hot dash operation are as follows. When the operation starts from the “AUTO” or “Hi” fan speed or when the fan speed is changed to “Hi” during heating operation. If the temperature difference between the

room temperature with the compressor rotating at maximum speed and the set temperature is (#TWMAX : refer to Table 2) and present room temperature is 10˚C or less, Hot dash will start.

(2) Conditions for releasing Hot dash operation (compressor maximum rottion speed period) are as follows.

The limit time for compressor maximum speed operation is exceeded.

The room temperature reaches the heating preset temperature (including heating shift value) + SFTDSW.

The thermostat is turned OFF. (When Hot dash is released by above 1, PI control starts without operating fixed speed periods 1 and 2.) (3) The ther mostat OFF temperature during HOT dash operation is heating preset temperature (including heating shift value) + SFTDSW + 3˚C, and after the thermostat is turned OFF, Hot dash is finished and the PI control starts. (4) The minimum ON time of the compressor is 3 minutes, and minimum OFF time is also 3 minutes. (5) The compressor speeds in the fixed speed perids 1 and 2 after releasing the Hot dash maximum rotation (Wtd1 and Wtd2) are determind as in Table 2 depending on the maximum rotation holding time (#td). (6) The time limit to hold the maximum rotation (WMAX) of the compressor in the normal heating operation (other than Hot dash) is within 60 minutes when the room temperature is 18˚C or more. If the room temperature is less than

18˚C, there is no time limit. (7) During initial cycle operation, preheating operation, defrosting (including balancing operation after defrosting) or AUTO-FRESH defrosting, the operation lamp will blink at intervals of one second. (8) Preheating operation is determined as follows; preheating comes on when heat exchanger temperature <YNEOF - 0.66˚C when operation is started with start / stop switch; preheating mode is released when heat exchanger

temperature> YNEOF. (9) Rotation speed of compressor is limited to the value of Rating for Heating (WSTD) + 2000 / 2 min-1 or less in “Low” fan operation mode. (10) In “Super Low” fan operation mode, when room temperature drops below 18˚C, indoor fan operation will stop. When room temperature reaches 18˚C + 0.66˚C, Super Low fan operation will start again. However during preheating

or preheating after defrosting, Super Low fan operation will not stop even if room temperature drops below 18˚C.

Note:

1. Refer to data in Table 1 in page 41 for each constant shown by capitital letters in the diagram.

2. [’ ] means minute and [” ] means second (ex. 30’ , 50”) in the diagram.

650min-11.66˚C 750min-12.00˚C 800min-12.33˚C 850min-12.66˚C

950min-13.00˚C 1000min-13.33˚C 1050min-13.66˚C 1150min-14.00˚C 1200min-14.33˚C 1250min-14.66˚C 1350min-15.00˚C 1400min-15.33˚C 1450min-15.66˚C 1550min-16.00˚C 1600min-16.33˚C 1650min-16.66˚C

2150min-11700min

-1

3150min-12500min

-1

4150min-13300min

-1

Less than 10 minutes 10 minutes to less

than 20 minutes 20 minutes or more

Max. speed (WMAX) – Min. speed (WMIN)

Preset temp. (including shift) – Poom temp.

td (Hot dash time)

Wtd1 Wtd2

Table 1 Speed specification during fixed rotation period

Table 2 #TWMAX

Preset temperature

for heating

"AUTO" fan mode is setting Start

3’ max.

30’ 30’

1’ 10’ 10’

10’

15’

30’ 30’ 30’ 30’ 30’ 30’

15’

15’ 15’ 15’

15’ 15’ 15’ 15’ 15’

3’

Preheating released

Controlled by heat exchanger temperature

Start/Stop Switch Thermostat judgement Defrost signal Preheating judgement

Super Hi Hi Med Lo Super Lo

10’

Indoor fan

Reversing valve

Operation lamp

Outdoor fan

Maximum

Minimum

Rated value

Compressor rotation speed

Wtd

3000

(WMAX)

Fixed rotation period 1

Controlled by heat

exchanger

temperature

exchanger temperature

Thermostat

OFF

Thermostat OFF

stop

stop stop

start

Preheating released

Controlled by heat exchanger temperature

Controlled by heat

Fixed rotation period 2

(WSTD)

(WMIN)

(+)SHIFTW

SFTDSW

S t d

– 51 –

Page 44

Note:

(1) The DEFROST inhibit period is DFTIM. After DEFROST is completed, defrost signal is not accepted for

DFTIM. However, first inhibit period is fixed at 40 ninutes.

(2) If the temperature difference between the room temperature and set temperature is great after the DEFROST

is completed, compressor can keep maximum rotation speed (WMAX) for up to 120 minuets. (3) DEFROST period is a maximum 12 minutes. (4) When operation is stopped during DEFROST, the mode switches to AUTO FRESH DEFROST. (5) AUTO FRESH DEFROST does not work within 15 minutes after the operation is started or after DEFROST is

completed.

Note:

1. Refer to data in Table 1 on page 41 for each constant shown in capital letters in the diagram.

2. In the diagram, s’ attached to the top right of number mean minute, s” means second. (ex. 30’, 15”)

Reversing valve defrost

WMAX

Reversing valve (Power ON mode in heating)

Operation lamp

Outdoor fan

Indoor fan

Defrost signal

Start/Stop switch

Preheating OFF

More than DFTIM

Fan speed "Hi" setting

Preheating judgement

Lo Lo

10’

30’ 30’

15’

Stop

More than 15’ AUTO FRESH DEFROST

Super Lo

Hi Med Lo

Deceleration period

Defrost period

Max. 12’

Max. 3’

3’

30’

1’ 1’

TDF

411

TDF 412

2400

3000

3000 3000

1950

TDF

413

TDF4

TDF

421

TDF 422

SGMNRP

– 53 –

Page 45

INPUT SIGNAL OPERATING SPECIFICATION REFERENCE

OPERATION OPERATION MODE AIR DEFLECTOR

PRESENT CONDITION

KEY INPUT

THERMO. ON (INTERNAL FAN ON)

THERMO. OFF (INTERNAL FAN OFF)

MAIN SWITCH ON

MAIN SWITCH OFF

CHANGE OF OPERATION

STOP

DURING OPERATION

STOP

DURING OPERATION

EACH MODE

AUTO COOL COOL FAN AUTO DRY DRY

STOP SWINGING AND MODE BECOMES INITIALIZING CONDITION.

INITIALIZING CONDITION OF EACH MODE.

ONE SWING (CLOSING AIR DEFLECTOR) 1 DOWNWARD 2 UPWARD

INITIALIZE 1 DOWNWARD

INITIALIZE 1 DOWNWARD 2 UPWARD

STOP AT THE MOMENT.

START SWINGING 1 DOWNWARD 2 UPWARD 3 DOWNWARD

STOP AT THE MOMENT.

START SWINGING 1 DOWNWARD 2 UPWARD 3 DOWNWARD

STOP AT THE MOMENT.

ONE SWING (CLOSING AIR DEFLECTOR) 1 DOWNWARD 2 UPWARD

INITIALIZE AT NEXT OPERATION.

STOP

DURING ONE SWING

STOP

DURING SWINGING

STOP

DURING SWINGING TEMPORARY STOP

DURING SWINGING

STOP DURING ONE SWING

STOP DURING SWINGING

DURING INITIALIZING

STOP

DURING SWINGING

AUTO SWING FUNCTION

STOP SWINGING TEMPORARILY. (SWING MODE IS CLEARED IF SWING COMMAND IS TRANSMITTED DURING TEMPORARY STOP.)

START SWING AGAIN.

AUTO HEAT HEAT CIRCULATOR

AUTO DRY DRY AUTO HEAT HEAT CIRCULATOR

COOL FAN DRY

EACH MODE

HEAT CIRCULATOR

– 54 –

Page 46

– 55 –

DESCRIPTION OF MAIN CIRCUIT OPERATION

Model RAS-25CNH11

Q202 NORMAL RESET

HI LO

+ –

RES

R203

D201

ZD202

R210

R211

R208

Q201

R202

C201

R204

C202

R201

R209

ZD201

35V 5V0V5V 12V 5V

MICRO

COMPUTER

Power is ON

35V

Voltage

24V

35V DC line

5V DC line

Base of Q201

Power is OFF

Collector of Q202

Fig. 1-1

Fig. 1-2

● The reset circuit initializes the program when power is supplied or power is restored following a power failure.

● RESET “Lo” or SET “Hi” activates the micro computer.

● Fig. 1-2 shows the waveforms in each circuit when power is ON and OFF.

● When the power is supplied, the voltages on the 35V and 5V DC lines rise, and when the 35V DC line becomes approx.

24V, ZD201 turns on and the voltage at the base of Q201 rises to turn Q201 on. Since the collector of Q201 goes “Lo” at this time, Q202 turns on and the reset input of the micro computer goes “Hi”. The 5V DC line has already been 5V at this time and the micro computer starts operation.

● When power is OFF, the voltage on the 35V DC line drops, and when it is approx. 24V, ZD201 turns off, Q201 and Q202

turn off, and the reset input of the micro computer goes “Lo” to reset it.

1. Reset Circuit

Page 47

– 56 –

2. Receive Circuit

● The Light receiving unit receives an infrared signal from the wireless remote control. The receiver amplifies

and shapes the signal and outputs it.

3. Buzzer Circuit

C702

12V

R710

ZD701

R709

R705

C701

LIGHT

RECEIVING

UNIT

+ –

Wireless input

Micro computer

● When the buzzer sounds, an approx.

3.9kHz square signal is output from buzzer output pin q of the micro computer. After 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.

Fig. 3-1 Buzzer Circuit

Sound wave

Metal diaphragm

Pizoelectric element

Fig. 3-2 Buzzer Operation

Micro computer

Buzzer output

BZ1

12V

R801

Q805

Fig. 2-1

Page 48

– 57 –

4. Auto Sweep Motor Circuit

Micro computer

4 3 2 1

IC501

12V

CN4

Auto sweep motor for horizontal air deflectors

Rotor

14 15 16

Fig. 4-1 Auto Sweep Motor Circuit (Horizontal air deflectors)

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

k – A

of the micro computer.

Micro computer pins

Step width

Horizontal air

deflectors: 10ms.

12345678

Horizontal air deflectors

Fig. 4-2 Micro computer Output Signals

● As the micro computer’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.

Rotation angle per step (° )

0.0879

Time per step (ms)

10Horizontal air deflectors

Table 4-1 Auto sweep Motor Rotation

Page 49

– 58 –

5. Room Temperature Thermistor Circuit

● Fig. 5-1 shows the room temperature

thermistor circuit.

010

Room temperature (˚C)

Fig. 5-2

20 30 40

Room temperature thermistor

Fig. 5-1

R309

C302

Micro computer

Room temp. input

Voltage at

(V)

R310

Heat exchanger temperature thermistor

Fig. 6-1

R307

C301

Micro computer

Heat exchanger temperature input

R308

010

-10 Heat exchanger temperature (˚C)

Fig. 6-2

20 30 40

Voltage at

(V)A

6. Heat exchanger temperature thermistor circuit

● The voltage at A depends on the room

temperature as shown in Fig. 5-2.

● 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 A depends on the heat exchanger temperature as shown in Fig. 6-2.

Page 50

– 59 –

7. Temporary Switch

Fig. 7-1

37 X1

C701 ZD701

R709

R603

R710

TEMPORARY SWITCH

SW701

12V

MICRO COMPUTER

Micro computer

Fan PMW output

Output divider

R920

Q903

35V

Q904

R904

R905

R921

R915

R910

R909

R906

R902

L901

RED

YEL

BLU

Terminal board D

D901 C901 R901

R903

C933

C940

0V 0V

R931

R932

R930

D902

Fig. 8.1

Fan current detection

5 4 3 2 1

C942

CN10

Indoor DC Fan motor

● The temporary switch is used to operate the air conditoner temporarily when the wireless remote control

is lost or faulty.

● The air conditioner operates in the previous mode at the previously set temperature. However, when the

power switch is set to OFF, it starts automatic operation.

Fig. 7-1

8. DC Fan Motor Drive Circuit

● Fig. 8-1 shows the indoor DC fan motor drive circuit.

Fig. 8-1

● The circuit produces the fan motor drive voltages, 8-33V, from 35V DC supplied from the outdoor unit and

controls the fan motor speed.

● Q903 is switched on and off according to the signal at fan PWM output pin

to control the voltage which

is smoothed by D901, L901 and C901 to drive the fan motor.

● The output voltage is divided by R901 and R903 and is input to divided voltage output pin

; the micro computer controls the fan PWM output so the output voltage is set to the specified value. The chopper frequency of the fan PWM output is 15.7kHz.

● In the Fan current detection circuit, 35V line current is detected by R906`R915 and input to fan current

detection pin 9. Microcomputer detects overcurrent comparing it with the current judgment value corresponding to the fan rotation speed.

Page 51

– 60 –

PWM output

Output voltage

Voltage at I

Voltage at J

Fig. 8-2

Fan Motor Set Wind Velocity and DC Voltage (between blue and red) Characteristics

Mode

Fan Speed

Connector blue-red voltage (V) Rotation Speed (min-1)

9.8 714

16.6 950

OVERLOAD

19.1 1,040

27.7 1,350

SUPER HI

27.7 1,350

16.0 930

18.7 1,020

20.9 1,100

SUPER HI

20.9 1,100

16.0 930

INDOOR FAN SPEED

HEATING

COOLING

DEHUMIDIFYING

Page 52

– 61 –

9. 12V Power Circuit

35V

R101

R104

REG1

C105

0V 0V 0V 0V

12V

D102

L102

C102

R102

R103

8 7 6 5

1 2 3 4

–

Fig. 9 — 1

● DC 35V supplied from the outdoor unit is controlled by switching of regulator 1, and is smoothed by D102,

L102 and C102 to produce 12V.

● Output voltage is divided by R102 and R103, and input to output dividing pin

to control switching, so

that output voltage is 12V.

Fig. 9 — 2

Waveform at

Out put Voltage

Page 53

– 62 –

● This circuit full-wave rectifies 220V AC applied between terminals A:B to produce a DC voltage of

220 x !2= 310V at the positive and negative terminals. However, the voltage is approx. 260-290V when the compressor

is operating. t

● The following describes the main parts components.

Model RAC-25CNH11

1. Power Circuit

(1) Reactor and power capacitor

The filter consisting of a reactor and power capacitor removes high harmonics components from the current containing high harmonics occurring when the compressor is operating to improve the power factor.

(2) Diode stacks

These rectify the 220V AC from terminal boards A and B to a DC power supply.

< Reference >

● If the reactor is faulty or the connection is defective,

the compressor may stop due to “abnormality in line voltage”, etc. immediately after it is started.

< Reference >

● When diode become defective, the compressor may

stop due to” abnormality in line voltage”, etc. immediately after it is started or no operation may be done as a DC voltage is not generated between the positive ! and negative @ terminals.

● When diode stack becomes defective, check

whether the 15A fuse has blown.

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000

00 0

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Terminal board

Varistor 1

15A fuse

NF coil

C807

L804

C805

R807

C812

C813

C808

C806

Varistor 3

Surge absorber

Black

Green

White

Inrush current protection relay

Stick relay

Power relay

Diode stack

Reactor

R802

R801

R806

DC voltage detection circuit

DC current detection circuit

Power module

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Page 54

– 63 –

(3) Smoothing capacitor

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

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VD (DC valtage)

Fig. 1-2

DC voltage (approx. 260-290V during operation)

DC voltmeter or teste (same as oscilloscop)

Fig. 1-3

Both ends of R802

Fig. 1-4

< Reference >

● DC voltage can be measured by connecting

both ends of R802 the control P.W.B. using a tester, etc.

● 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.

(4) Smoothing capacitor

This smoothes (averages) the voltage rectified by the diode stacks. A DC voltage is generated in the same way as in Fig. 1-3.

(5) C805 - C808, C812, C813, L804 (NF coil)

These 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, 3

These absorbs external power surge.

(7) Inrush protective resistor (R807)

This works to protect from overcurrent when power is turned on. R807 Short-circuit → Overcurrent flows in

rush protection ON mode Open → Overcurrent flows with power relay turned ON. (damaged each time power relay is turned ON) Diode stack and 15A fuse deteriorate.

< 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.

Page 55

– 64 –

2. Indoor/Outdoor Interface Circuit

● The interface circuit superimposes an interface signal on the 36V DC line supplied from the outdoor unit

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

● 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.

● Outdoor micro computer to indoor micro computer

Request signal output from IF transmitting output pin 64 of outdoor microcomputer input to transmitting circuit. Transmitting circuit and receiving circuit of the outdoor unit are provided inside HIC. Transmitting circuit intermits high frequency oscillation circuit of about 36kHz with comparator according to the request signal. This high frequency signal is applified by the transistor and is ourput from HIC = pin, then superimposed with DC 35V line via C701 and L701.

To prevent mis-operation, outdoor microcomputer does not accept receive signal whil outputting request signal.

The receiving circuit of the indoor unit consists of COM4. The interface signal from the outdoor unit, whose DC component is cut from DC35V line at C801, is waveform-shaped and rectified amplified in HIC, then input to receive input pin ( of indoor microcomputer.

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

● Indoor micro computer to outdoor micro computer

The communications from the indoor micro computer to the outdoor micro computer are the same. Fig. 2-3 shows the voltages and waveforms at each circuit.

Page 56

– 65 –

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

each other.

(Communications from indoor micro computer to outdoor micro computer)

(Communications from outdoor micro computer to indoor micro computer)

Fig. 2-1 Indoor/outdoor interface Circuit

Terminal board

C801

R802

C802

R803

R804

R806

5V5V5V

R805

OVOV

R702

L701

C701

C702

C709

C710

C708

C706

12V

R704

R703

C807

C805

R813

Q801

R814

R815

R821

R822

R807

R808

R809

R811

C804

R810

C803

R817

R819

R820

Q802

R818

C806

D801

COM801

IF receive input (SDI)

Micro computer

IF transmit output (SDO)

COM801

HIC

Inpoor P.W.B.

Outdoor P.W.B.

D101

Noise filter coil

I /F GND

I/F35V

HIC-l

Micro computer AX-8E21

IF transmit output (SDO)

IF receive input (SDI)

9 8

C704

C703

Page 57

– 66 –

(

Indoor micro computer

35V DC line

100 ms.

Leader

33ms. 1frame

Outdoor HIC

5V 0V

35V

0V 5V

(

5V 0V

35V

Indoor micro computer

35V DC line

Outdoor HIC

4.95ms.

Transmit / receive

switching time

33ms

1frame

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

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

Page 58

– 67 –

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Diode stack

Reactor

Inrush

current

protection

relay

Power relay

Stick relay

Noise Filter

Coil

FUSE(15A)

C812

C813

R807

C805

L804

R801

R802

1000

DC current (Id)

detect resistance

U coil

V coil

W coil

DC compressor

Motor

Power Module

3. Power Module Circuit

● Fig. 3-1 shows the power module and its peripheral circuits.

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.

Fig. 3-1 Power module circuit (U

is ON, V is ON)

Page 59

– 68 –

● DC 230V is input to power module and power module switches power supply current according to rotation

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

UVVW

Upper arm transistor

Lower arm transistor

Time

—

U transistor chopped U transistor ON

Voltage between

Upper arm transistor

current at

Chopping period

and

260V-380V

[]

●Upper arm transistor is controlled to ON/OFF by 3.2kHz 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;

Fig. 3-2 Switching order of power module

N = 60/2 X 1/T

● Fig. 3-3 shows voltage waveform at each point shown in Figs. 3-1 and 3-4.

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; B

(1) When U+ transistor is ON: U+ transistor [ U coil [ V coil [ V– transistor [ DC current detection resistor [ Point B (Fig. 3-1)

When U+ transistor is OFF: (by inductance of motor coil) U coil [ V coil [ V– transistor [ Return diode [ Point A (Fig. 3-4)

* 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)

Page 60

– 69 –

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U coil

DC compressor motor

W coil

V coil

Power module

R806

DC current (Id) detection resistor

MP6501

1000

Fig. 3-5

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

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

● 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 91) for independent checking of power module.

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

Self-diagnosis

Self-diagnosis lamp and mode

lp (peak current cut)

LD301

Abnormal low speed

rotation

LD301

Switching incomplete

LD301

Blinks 2 times

Blinks 3 times

Blinks 4 times

Table 3-1

Control P.W.B.

LD301 Red LD302 Red LD303 Red

Self-diagnosis lamps

}

LD301

Blinks 10 times

Switching incomplete

Page 61

– 70 –

4. Power Circuit for P.W.B.

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

3A fuse

AC 220V

R805

C810

C811

C2 C5

VR2

R5 R6

D61

D62

D63

D64

D65

RC61

C61

C62

C63

C64

C65

C66

M52

—5V

5V 0V

12V

(12 - H)

(12 - E)

(12 - D)

(12 - C)

f g

C711

C712

R62

R63

R64

I / F 35V

I / F GND

C67

C51

RC62

R51

P151

M51

R52

R53

R54

R 3

ZD3

● In the power circuit for P.W.B., power voltage for microcomputer, peripheral circuits, and power module

drive and, as well as DV35V, are produced by switching power circuit.

● Switching power circuit performs voltage conversion effectively by switching transistor Q1 to convert

DC270V voltage to high frequency of about 20kHz to 70kHz.

● Transistor Q1 operates as follows:

(1) Shifting from OFF to ON

● DC about 270V is applied from smoothing capacitors C810 ! and C811 @ in the control power circuit.

With this power, current flows to base of transistor Q1 via R1 and Q1 starts to rurn ON. Since voltage in the direction of arrow generates at point C at the same time, current passing through R5, R6 and D2 is positive-fed back to Q1

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

Page 62

– 71 –

(2) During ON period

● Collector current of Q1 is increased directly. In this period, base current is fixed by saturation characteristic

of transformer.

(3) Shifting from ON to OFF

● In this circuit, feed back (negative) is applied from 12V output. When voltage between both ends of C65

reaches the specified value, M51 is turned ON and current flows between pin 1 and 2 of P151, secondary side is turned ON, current flows to base of Q2 via R9 and D4, Q2 is turned ON, and Q1 base current is bypassed to turn Q1 OFF.

(4) During OFF period

● During Q1 ON period, energy as shown below is charged at primary winding of transformer and is

discharged to each secondary coil during OFF period:

Energy = LI2/2.

L : Primary inductance

I : Current when Q1 is OFF Each coil C61 - C67 is charged according to the winding ratio. ZD3 turns ON Q2 to bypass Q1 base current during ON period to fix value of voltage in the direction of

arrow. For example, when applied voltage to Q1 is high, voltage in the direction of arrow will rise, and current

bypassing to Q2 is increased.

● Overcurrent flows at Q1 due to charged current at C61 - C67 when starting operation.

● When ZD3 reaches On voltage as a result of the voltage generated in the direction of arrow by Q1 collector

current, Q2 is turned ON and Q1 base current is bypassed.

● By limiting base current with Q2, Q1 is prevented from allowing too much collector current to flow.

Page 63

– 72 –

• Check 5V (±0.5V), 12V and @ 5V

using test pin.

• Check as follows to measure power voltage of upper

arm (U,V,W) and lower arm drive circuit: a) U phase of upper arm

Apply ! terminal of tester to pin 8 of PQ501 Apply @ terminal of tester to pin 7 of PQ502

b) V phase of upper arm

Apply ! terminal of tester to pin 8 of PQ501 Apply @ terminal of tester to pin 7 of PQ502

c) W phase of upper arm

Apply ! terminal of tester to pin 8 of PQ503 Apply @ terminal of tester to pin 7 of PQ503

d) Lower arm

Apply ! terminal of tester to pin 8 of PQ601 Apply @ terminal of tester to pin 7 of PQ602

Test pin

DC voltmeter or tester

For PQ501 — PQ503 and PQ601 — PQ603, apply

terminal to pin 8, @ terminal to pin 7. If short-circuited between pins, it could be damaged.

When measuring drive voltage, if short-circuited between pins, it could be damaged.

PQ601 603

PQ501 503

CAUTION

• When power circuit for P.W.B. is estimated as abnormal:

(1) Check that power voltages of 5V, 12V on the control P.W.B., and also power voltage of upper arm

U, V and W and lower arm are specified values.

(2) Abnormal only when output of 5V voltage has decreased:

Regulator 1 is abnormal, short-circuited between 5V and 0V, or output too high.

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

1 Mainly; 2 Fan, operation, power, or inrush current protective relays (short-circuit inside relay, etc.) 3 HIC abnormal

Regulator 1 abnormal, etc. Primary side short-circuited. When secondary side is short-circuited, primary side is normal because of overcurrent protective device Voltage rise when primary side is open, feed back system abnormal.

(4) When each phase of upper arm U, V, W or lower arm power is abnormal:

D61 - D65, RC61, RC62 or drive circuit is abnormal.

(5) When all voltages are abnormal:

Q210, ZD201, R205, etc. may be abnormal. Be careful, if Q201 is abnormal, other parts such as power module, HIC, regulator could be defective.

Fig. 4 - 2

Be careful not to short-circuit by touching of tester terminals, etc.

CAUTION

+ 1V

1 . 5 V

(

+ 1V

1 . 5 V

(

Page 64

– 73 –

5. Reversing valve control circuit

❈ Since the reversing valve is differential pressure system, even when reversing valve is ON (collector

voltage of Q701 is about 0.8V normally), compressor rotation speed instructed by indoor microcomputer exceeds 3300min-1, signal at pin 24 of microcomputer changes, and collector voltage of Q701 will be about 36V.

This does not indicate trouble. When rotation speed is reduced under 2700min-1, collector voltage of Q701 will fall to about 0.8V again. To measure voltage, connect Œ terminal of tester to D701 anode and œ terminal to D line on the terminal board.

● By reversing valve control circuit you can switch reversing valve ON/OFF according to instruction from

indoor microcomputer and depending on operation condition. Voltage at each point in each operation condition is approximately as shown below when measured by

tester. (When collector voltage of Q701 is measured)

¤

§

£

Reversing valve

CN2

D 701

Q 701

R 705

R 706

I/F 0V

I/F 35V

12V

R 233

PQ 701

DC voltmeter or tester

HIC

8E21

Operation condition Collector voltage of Q701

Cooling

Heating

Dehumidifying

General operation of Cooling In normal heating operation

MAX. rotation speed instructed by indoor microcomputer after defrost is completed

Defrosting SENSOR DRY

About 36V

About 0.8V

About 35V About 35V

Table 5-1

Fig. 5 - 1

Page 65

– 74 –

6. Rotor Magnetic Pole Position Detection Circuit

£££ £

000

)

HIC

R101

R102 R103

C104

C105

C106

C103

C102

C101

R106R105

R104

59 58 57

Outdoor

microcomputer

+ 12V

zzz

Voltage at point

0.6V

Voltage at point

B- transis-

tor ON

C- transistor ON

transis-

tor ON

transis-

tor ON

Voltage at point A about 230V

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

● Motor-induced voltage signal (voltage at point A ) is phase-shifted by 90° by passing lowpass filter

consisting of R101, R104 and C101 to make triangular wave (voltage at point B ). In HIC, 3 phases of this triangular wave are synthesized to produce composite wave (voltage at point C ). This composite wave becomes a triangular wave with period of 1/3 times compared with original triangular wave.

● Voltages at points B and C are compared by comparator to make voltage at point D.

Voltage at point D is taken into microcomputer and timing of switching from V– transistor to W– transistor is made by rising waveform, and timing of switching from V+ transistor to W+ transistor is made by failling waveform.

● For other 2 phases (V phase and W phase), the operation is the same and phases are shifted by 120°

and 240° respectively compared with U phase waveform.

Page 66

– 75 –

7. Drive Circuit

(1) Upper Arm Drive Circuit

● Fig. 7-1 shows the upper arm drive circuit.

The circuit configuration is completely the same for phases A, B and C.

● When pin ° of HIC goes "Hi" [ "Lo", a photocoupler between PQ501 pins 1 and 2 turns on and current

flows to terminal d [ R501 [ PQ501 [ R504 [ power module’s Bu+ terminals [ Eu+ terminals [ D502 [ D501 [ terminal e and drives the upper arm transistors. (Fig.7-2)

● As described in the rotor magnetic pole position detecting circuit, the upper arm drive circuit supplies

current to the bases of the transistors on the power module's positive e side which turn on or off according to the position detection signals. The signals according to the position detection detection signals are output from pins e, r and t of the micro computer and are input to pins 2 of photocouplers PQ501 PQ503 via driver IC1.

Fig. 7 - 1

Fig. 7 - 2 Forward Current Waveform at Point A

Page 67

– 76 –

● When pin

of HIC-1 then goes "Hi" [ "Lo", a photocoupler between PQ2 pins 1 and 2 turns off and the reverse bias current flows to C501 [ power module’s Eu+ terminals [ Bu+ terminals [ R504 [ PQ501 Switching incomplete to cut off the upper arm transistors. (Fig.7-3)

● R507 is used to charge C501 initally.

● The operation is the same for B

and C+ phases.

5 6

PQ2

Power module

A+phase

—

R401

R404

D401 D402

C401

R407

Current at point

Reverse bias current

Fig. 7-3 Waveform of Transistor Base Current (Reverse Current at Point )

Page 68

– 77 –

(2) Lower Arm Drive Circuit

● Fig. 7-4 shows the lower arm drive circuit.

The circuit configuration is completely the same for phases A, B and C.

● When pin ﬁ of the micro computer goes "Hi" [ "Lo", a photocoupler between PQ601 pins 1 and 2 turn

off and reverse bias current flows to C411 [ power module's Ew– terminals [ Bu– terminals [ R604 [ PQ601 to cut off the lower arm transistors. (Fig. 7-5)

● R607 is used to charge C601 initally.

● The operation is the same for B

–

and C– phases.

● When the peak current cut off function operates, HIC-1 º pins become 0V, PQ501-PQ503 and PQ601-

PQ603 turn off and the upper/lower arm drive circuits stop.

● when a reset signal is applied, HIC pins 7 and ¤ become open, PQ501-PQ503 and PQ601-PQ603 turn

off and the upper/lowerarm drive circuits stop.

● When pin ﬁ of the micro computer goes "Lo" [ "Hi", a photocoupler between PQ601 pins 1 and 2 turns

on and current flows to terminal i [ R601 [ PQ601 [ R604 [ power module's BU– terminals [ Ew– terminals [ D602 [ D601 [ terminal k and drives the lower arm transistors. (Fig. 7-4)

● The signals which turn on or off according to the position detection signals are output from pins ‹›ﬁ

of the micro computer in the same way as in the upper arm drive circuit and are input to pins 1 of photocouplers P601 and PQ602 via driver IC1.

● No chopper signal is input to the lower arm drive circuit.

1 2

5 6

1 2

PQ5

PQ6

PQ7

5 6

R411 R414

R412 R415

R413 R416 R417

C411

CN28

Power module

A- phase

B- phase

C- phase

Fig. 7-4

D411 D412

1 2

5 6

1 2

PQ5

PQ6

PQ7

5 6

R411 R414

R412 R415

R413 R416 R417

C411

CN28

Power module

A- phase

B- phase

C- phase

Fig. 7-5

D411 D412

Page 69

– 78 –

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.

Table 8-1

Circuit block

Basic operation

Peak current cutoff circuit

Set value circuit

Voltage amplifier circuit

Reset circuit Trip signal

synthesis circuit

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 (HIC 33 _ 38 from microcomputer 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/ab-

sence of lp signal or reset signal.

Fig. 8-1 Micro computer(AX-8E21) and peripheral circuits

AVcc

Micro computer

AX-8E21

RESET

POR

Chopper

Cool

Power module positive terminal

R229 R230

R231

12V

ZD301

C204

R232

0V0V

(7-C)

COMl(2/4)

R202

C202

D201

Normal

To upper arm drive circuit

R201

R205

R806

Normal Hi at Reset Lo Normal Hi

Power moule negative terminal

C205

C206

(Current detection

Resistor)

R207

R206

Q201

R21

Q203

Q202

R222

R208

R204

R203

D202

FANC

VRI

3 2

5 6

HIC - 1

Page 70

– 79 –

Reset circuit

Reset voltage

Peak current cut off circuit

Trip signal synthesis circuit

Chopper signal

Reset Signal

Ip signal (interrupt signal)

Overload external set value circuit

DC current level

Voltage amp. circuit

Detection resistor

R806

DC current

Outdoor micro computer

(AX-8E21)

Drive signal

Compressor motor

DC current

Power module

photocoupler

DC 260V

290V

Fig. 8 - 2

18A

0.9V

Voltage at point

Micro computer

Voltage at pin

Voltage at point

DC current (ld)

POR

Micro computer AX-8E21

chopper

(A)

30 56

0V 0V

Normal Hi

Upper arm Drive circuit

Lower arm Drive circuit

DC current

(current detection resistor)

COM 1 (2/4)

R202

R201

Normal Hi

R806

D201

C202

HIC - 1

Fig. 8 - 3 Peak current cut off circuit and Waveforms at Each Section

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

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

● Ip cut off circuit detects an instantaneous large current and stops drive output signal to protect parts such

as power module, etc.

● As shown in the figure, when current exceeding 18A flows, voltage at point A detected by detection

resistor is input to e terminal of COM (A). If it exceeds d terminal voltage, which is the set value, output pin voltage (point B) of COM (A) changes from Lo to Hi. Thus, Q1 is turned ON to stop drive curcuit and, at the same time, voltage at point C changes from Hi to Lo to send Ip signal to pin ™ of microcomputer (observed by pin º of HIC) and microcomputer stops drive.

● On the other hand, e terminal voltage is pulled up by R1, and DC current becomes 0A. Even when voltage

at point A returns to 0V, (power is not supplied - current value of zero), Output is temporarily held in Hi state since voltage at - terminal is high. (memory function).

● Just before drive signal is output the next time, Microcomputer switches pin £ from Hi to Lo (observed

by pin ⁄ of HIC), so that e terminal voltage < d terminal voltage to release memory function and return to initial state.

Page 71

– 80 –

(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 judgement 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 micro computer software with the DC current value.

Judgement OVL 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

OVL start current data

Motor control process

Detection

resistor

To power module negative terminal

DC current

(R806)

Overload externally set value circuit

Voltage amp.

circuit

(External judgement)

(Internal judgement)

DC voltage

AX-8E21 Micro computer

Rotation speed data

Fig. 8 - 4 Overload Control System Configuration

External judgement value

Judgement value according to the rotation speed

(internal judgement value)

Rotation speed

DC current

Fig. 8 - 5

1. Overload external judgement circuit

● The filter consisting of R320 and C1 removes high harmonic components from the voltage generated by

the current flowing to R806, R2 and C304 average the voltage. This voltage is then input to OP1 pin 5 and amplified and is supplied to micro computer pin @ which is comparedwith the voltage at pin #. If the voltage at pin @ is higher than that at pin #, the micro computer enters the overload control mode.

● Fig. 8-7 shows the rotation speed control. When the voltage at pin 9 of HIC exceeds the set value at pin

HIC 8, the micro computer decreases the rotation speed of the compressor and reduces the load regardless of the rotation speed commanded by the indoor micro computer.

Page 72

– 81 –

Commanded rotation speed

Actual rotation speed

Acceleration

Deceleration

Acceleration

Deceleration

Rotation speed of compressor

Voltage at HIC Voltage at HIC

8 9

Fig. 8-7

Micro computer

(AX-8E21)

OV OV

DC current

R806

R201R205

C206

R211

R206

R207

Q201

Q203

D202

R203

Q202

R208

R222

R204

VRI

FANC

R229

R230

R231C204

OPI

Power module positive terminal

Cool

HIC - 1

ZZZ

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 micro computer. Receiving this, the micro computer 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 R201 and C202 removes high harmonic components from the voltage generated

from the DC current flowing to the detection resistor, and R205 and C206 average the voltage and supplies it to OP1 pin 5 OP1 forms a non-inverting voltage amp. circuit together with the peripheral elements.

● The micro computer stores the set values which vary according to the rotation speed as shown in Fig. 8-

8. When the DC current level exceeds the set value, the micro computer enters the overload control state. The compressor motor is controlled in the same way as in external judgement described previously.

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

Amplification : high [ DC current : low

Amplification : low [ DC current: high

{

Fig. 8-8

Page 73

– 82 –

● R229, R230, R231 detect the DC voltage at the power circuit. The micro computer receives a DC voltage

(210-300V) via HIC 64 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, R229, R230, R231 are provided to perform the same overload judgement even when the voltage varies.)

< 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.

● The RAC-25CNH11 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 Fig. 8-9. (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. 8A as shown in Fig. 8-10.

DC current

Rotation speed

Amplification : low DC voitage : low DC current : high

Amplification : 8 times DC current : 260v

Amplification : high DC voltage : high DC current : low

Fig. 8-8

DC 260-290V

DC current

Detection

resistor

Power module

Compressor motor

U V W

Fig. 8-9

Chopper duty: high

W transistor

ON-time

DC current (A)

8 6 4 2 0

Fig. 8-10

DC voltage (start current)

DC voltage: low DC voltage: 260V DC voltage: high

Set value

Time

Start

Page 74

– 83 –

9. Trip Signal Synthesis Circuit

● Fig. 9-1 shows the trip signal synthesis circuit.

This circuit is provided to stop the drive signal, etc. according to whether or not the Ip cut signal or reset signal is present.

● Table 9-1 shows to which circuits the various modulation signals are transferred.

For example, the chopper signal is only transferred to the upper arm transistor drive circuit, and the reset signal is transferred to the micro computer and upper and lower arm transistor drive circuits.

● On the other hand, pins ‹-° of the HIC-1 change from "Lo" to "Hi" alternately and supply the voltage

to PQ501-PQ503 and PQ601-PQ603.

● The chopper signal from the micro computer is inverted by Q1 and turns PQ501, PQ502 or PQ503 ON

or OF to which voltage is applied at a high frequency to supply curent, thus transferring the upper arm drive signal.

● When the reset voltage is "Lo", the base of Q2 goes “Lo”, to turn Q2 OFF and also stops the operation

current of PQ601-PQ603 to switch OFF the lower arm drive signal. With the upper arm transistor drive circuit, the base of Q1 goes “Lo”, and the micro computer stop supplying a voltage to PQ501-PQ503, thus switching OFF the drive signal.

● The peak current cut off (Ip cut) signal fixes the base of Q1 and Q2 in the upper/lower arm transistor drive

circuits at “Lo” to switch OFF the drive signal in the same way as when the reset voltage is “Lo”.

Modulated signals

Circuit

Chopper signal Start current limit signal Peak current cut off signal Reset signal

–––– ––––

Micro Computer

Upper arm transistor

drive circuit

Lower arm transistor

drive circuit

–––– ––––

Table 9-1 Circuits to which trip signals are transferred

R223

PQ501

R224

PQ502

R225

PQ503

R226

PQ601

R227

PQ602

R228

PQ603

Chopper

Micro computer AX-8E21

RESET

HIC - 1

Z0301

R232

12V

Normal: Hi Reset: Lo

Ip Cut off

Fig. 9-1 Trip Sigmal Synthesis Circuit

Page 75

– 84 –

10. Temperature Detection Circuit

● 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 e5V is

divided by the over heat thermistor and R301 and the voltage at pin & of HIC.

● HIC the voltage at pin & and the set value stored inside, and when it exceeds the set value, the micro

computer judges that the compressor is overheated and stops operation.

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

Therefore the resistance of the Defrost. thermistor becomes high and the voltage at pin * of HIC drops. If this voltage becomes lower than the set value stored inside, the micro computer starts defrosting control.

● During defrosting operation the micro computer transfers the defrosting condition command to the indoor

microcomputer via the SDO pin IF transfer output of the interface.

CN4

Over heat thermistor

+5V

R301

Over heat

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

Defrost thermistor

+5V

Defrost

R302

Over heat thermistor

+5V

R301

Over heat

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

Normal: 2.4V or more Defrost: 2.4V or less Reset: 2.9V or more

CN5

Micro computer

(AX-8E21)

HIC

Fig. 10-1

Page 76

– 85 –

11. Reset Circuit

● Reset circuit performs initial setting of the microcomputer program before power is turned on.

● Microcomputer resets program with reset voltage set to Lo, and program can be operated with Hi.

● Fig. 11-1 shows the reset circuit and Fig. 11-2 shows waveform at each point when power is turned on

and off.

● When power is turned on, 12V line and 5V line voltages rise and 12V line voltage reaches 7.2V (Zenor

voltage of ZD501), ZD301 is turned ON, Q2 and Q3 are turned ON and reset voltage input to pin & of microcomputer is set to Hi. By ZD501, reset voltage maintains input of pin & at L0 until VDD of microcomputer rises to 5V to obtain operable status.

● When power is shut off and potential of 12V is lowered, ZD501 is shifted to OFF. However, since reset

voltage is feed back to Q2 by R4, Q2 maintains ON state until 12V line voltage drops to about 7.6V. This prevents reset voltage from chattering due to voltage change in 12V line.

12V line

5V line

12V line

5V line

Reset voltage

Fig. 11-2

Time

Power is ON

V oltage (V)

Power is OFF

V oltage (V)

R232

12V

ZD301

HIC-1

Micro computer

AX-8E21

RESET

Normal: Hi Reset: Lo

Fig. 11-1

Page 77

– 86 –

REVERSING VALV E

SUCTION TANK

SERVICE V ALVE

(3/8)

INDOOR UNIT

SINGLE-ENDED UNION (3/8)

SINGLE-ENDED UNION (1/4)

COOLING / HEATING CAPILLARY

CHEK VALVE

FILLING PIPE

HEATING CAPILLARY

COMPRESSOR

REFRIGERATING CYCLE DIAGRAM

COOLING

OUTDOOR UNIT

REVERSING VALVE

SUCTION TANK

SERVICE V ALVE

(3/8)

INDOOR UNIT

SINGLE-ENDED UNION (3/8)

SINGLE-ENDED UNION (1/4)

COOLING / HEATING CAPILLARY

CHEK VALVE

FILLING PIPE

HEATING CAPILLARY

COMPRESSOR

HEATING

OUTDOOR UNIT

Page 78

– 87 –

SERVICE CALL Q & A

MODEL RAS-25CNH11 /RAC-25CNH11

Cooling operation

The compressor has stopped suddenly during cooling operation.

Dehumidifying operation

The fan speed cannot be changed.

Cool air is blown in the dehumidifying mode.

The operation is not stopped when the preset room temperature is changed higher using the remote controller during dehumidifying operation.

Check if frost has formed on the indoor unit heat exchanger. Wait 3

4 minutes until it is

defrosted.

If the air conditioner operates in the cooling mode when it is cold, frost may form on the heat exchanger of the indoor unit.

The fan speed is fixed at "Lo" in the dehumidifying mode.

This is for higher dehumudifying efficiency. It is not a maifunction.

This is the case of ➁ in A4. A temperature slightfy lower than the actual room temeprature becomes the set temperature and the dehumidifying operaion is done if possible.

Though the preset room temperature is set higher than actual room temperature using the remote controller, dehumidifying operation is done.

The dehumidifying mode operates as follows by comparing the preset room temperature and the actual room temperature.

➀

When room temperature > preset room temperature, operation is

done according to the preset room temparature of the remote controller.

➁

When room temperature < preset room temperature, regardless of the preset room temperature, a temperature slightly lower than the actual room temperature automativally becomes the set temperature.

Sin ce Q4 is the case of above

➁

, it is not possible to operate using the room temperature control. Turn off using the Start/Stop switch once, set the preset room temperature again, then turn on using the Start/Stop switch.

Page 79

– 88 –

Heating operation

The circulation stops occasionally during the heating operation.

Even when the fan speed is set to "Hi" or "Med", the operation starts in the "Lo" mode.

After the Start/stop switch is pressed to stop heating operation, the outdoor units still operates with the Operation lamp lit.

This occurs during defrosting. Walt for 5

10 minutes

until the outdoor unit is defrosted.

At the begining of the heating operation, the fan speed is held to "Lo" for 30 seconds. If "Hi" is selected, operation is done at "Lo" first, then "Med" for 30 seconds and then is switched to "Hi".

If the external temperature is too high, heating operation may stop to protect the unit.

Auto fresh defrosting is carried out. The system checks the outdoor unit and defrosts it if necessary before stopping operation.

Auto fresh defrosting

Page 80

– 89 –

Q10

Auto operation

In the auto operation mode, the fan speed cannot be changed using the fan speed selector switch.

Q11

How is operation mode decided in AUTO operation?

Q12

Is it possible to adjust room temperature in the AUTO operation mode?

A12

The following conditions are set automatically: In the cooling mode: Room temperature is set to 27

C. In the dehumidifying mode: Temperature is set to a value slightly lower than present room temperature. In the heating mode: Room temperature is set to 23

C. You can raise set room temperature up to 3

C by using



, or lower it up to 3oC by

using 6

 .

When the set temperature has been changed in the AUTO operation mode, the operation mode is decided from the next operation according to the changed set room temperature. for example, If the set room temperature was lowered by 2

C in cooling operation, each mode will operate in the following conditions: Cooling: Room temperature is higher than about 25

C. Dehurnidifying: Room temperature is about 21

C-25oC. Heating: room temperature is lower than 21

Nice temperature reservation

Q13

When ON-timer is set, the system starts woring earlier than the reserved time.

Q14

Is it possible to use the Nice temperature reservation in the dehumidifying operation?

A14

No, it is impossible. This works only in the cooling and heating operation.

A13

The Nice temperature reservation is working correctly. It starts working enough to reach the preset temeprature at the reserved time. It will turn on up to 80 minutes earlier than the reserved time.

Q10

The auto fan speed mode is set automatically.

A11

Automatically, Heating, Cooling or Dehumidifying is chosen according to the room temperature. Cooling: Room temperature is higher than about 27

Dehumidifying: Room temperature is about 23

C-27oC

Heating: Room temperature is tower than 23



Page 81

– 90 –

Q15

Even when the reserved time is the same, the system turns on at a different time.

Wireless remote controller

Q16

The timer setting cannot be done.

Q18

The reserved time is erased though the timer was set.

Q17

The present time display is turned off too soon.

Common/Others

Q19

In the auto fan speed mode, the fan speed changes over between "Hi", "Med" and "Lo".

Q20

The noise from the outdoor gets louder at the start of operation.

Q21

The noise of the outdoor unit changes from time to time.

Q21

The room temperature differs from the preset temperature set by the room temperature control.

Q21

The air does not come out immediately after starting operation.

A20

This is not a problem. Since the compressor is operated at full speed to increase heating/cooling capacity when starting operation, it gets louder.

A21

This is not a problem. The speed of the compressor varies depending of the temperature difference between the preset temperature of the thermostat and the room temperature.

A22

The room temperature may differ from the preset temperature due to the structure of the room, air flow condition, etc. If there is a difference, adjust the preset temperature to obtain the optimum room temperature.

A23

After the power is turned on, when the heating or dehumidifying operation is set, the unit performs heatrunning operation for 1 minute. In the heating operation, the operation lamp blinks for this period. It is not a malfunction.

A18

The reserved time may have been passed. When the present time reaches the reserved time, the reserved time is erased.

A15

The Nice temperature reservation is working correctly. The turn-on time varies depending on the conditions of the room. In the heating operation, since the system calculates and corrects the starting time to reach the preset temperature at the reserved time under the current conditions, the operating time is defferent every day.

A16

Has the present time been set? If the clock is not set, the timer cannot be set.

When the present time is set, the display blinks for about 3 minutes.

The present time display appears for about 10 seconds. The timer set display has priority.

A17

A19

This is not a problem. The system automatically controls the fan speed to protect the blowing out of cold air.

In the Auto fan speed mode, the system detects the heat exchange temperature and automatically changes the fan speed to "Hi", "Med" and "Lo" when the temperature is low.

Page 82

– 91 –

TROUBLE SHOOTING

Model RAS-25CNH11 / RAC-25CNH11

PRECAUTIONS FOR CHECKING

C D

Outdoor unit electric parts

0V Line

Main P.W.B.

Compressor motor

Indoor unit

electric parts

Control

P.W. B .

Power circuit

1,000

µF

ZZZ

µF

ZZZ

Power source from an indoor unit 1 ∅,

220V, 50Hz

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

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

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

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

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

approx. 311-260V approx 1311V approx 311V

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

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

DANGER!

Don’t install

the ground

line.

Oscilloscope

Outdoor unit P.W.B.

Page 83

– 92 –

F-Cabel (∅2, single lead)

Soldering iron of 30 _ 75W

DC voltmeter or tester (same as in case of oscilloscope)

Do not use a soldering iron with built-in transformer : the fuse built in the transformer would blow out.

The smoothing capacitors (1,000µF) are charged to about 340V. Don’t forget to discharge them before attempting access to electric parts.

Both ends of R802

Plug

DISCHARGING CAPACITORS

1. Turn off the indoor unit’s power switch or unplug the power cord, and wait for a minute or so.

2. Open the cover of the electric parts compartment. Discharge electricity from smoothing capacitors (1,000µF) by connecting the leads of a

soldering iron of 30 _ 75W to the terminals provided for this purpose. Continue discharging for more than 15 seconds.

CUTTING OFF POWER SUPPLIED TO THE POWER CIRCUIT

Remove the receptacle of the gray / brown lead wire connected to the smoothing capacitor from control P.W.B. bef ore performing operation chec k of each point in the circuit.

When checking conductivity at each point of circuit in electrical parts of outdoor unit, to prevent secondary trouble, disconnect gray / black lead wire connected to smoothing capacitor from control P.W.b. in order to shut off power to the power module before checking. Connect (+) side of C516 and 5V using clip at this time. If this is not done, there will be no drive output. (LED310 blinking 10 times mode is set.)

Before checking electric parts of the outdoor unit, disconnect the power line of the power circuit to cut off supply power. This is necessary to protect the parts.

Page 84

– 93 –

Be sure to replace the rainproof cover after checking (rainwater would enter if it is not installed).

R inproof cover (transparent)

Page 85

– 94 –

CHECKING THE INDOOR/OUTDOOR UNIT ELECTRICAL PARTS AND REFRIGERATING CYCLE

[ MODEL RAS-25CNH11 / RAC-25CNH11 ]

Does the timer or dehumidifying lamp on the indoor unit blink?

Set to room temperature 16°C in the cooling mode or to 32°C in the heating mode, and press the start/stop button.

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

Is the compressor in the outdoor unit operating?

Remove the decorative cover and electrical parts cover and check the pin voltages of CN3 (brown and red wires). Pin 5 : +35 V, pin 3 : 0V

See "Troubleshooting when the timer lamp blinks".

Check the outdoor electrical parts.

Timer lamp

Dehumidifying lamp

No Yes

Yes No

Is approx. 35V DC being generated? Is the polarity correct?

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

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

2-second off.

Check to see whether the Fcable is connected incorrectly or disconnected.

Set the service switch on the outdoor unit to "cooling". Does the compressor operate? (After checking, be sure to return the service switch to "normal".)

See Outdoor unit selfdiagnosis lamp lighting mode.

Check the refrigerating cycle. Check the outdoor electrical parts. Check the indoor electrical parts.

Blinking other than one-time

One-time blinking

Yes

Normal

D101

+–

ABC D

Service switch

LD301 LD302

LD303

Yes

Page 86

– 95 –

No.

Blinking made of timer lamp

Reason of indication Possible caues

5 sec.

1 time

5 sec.

2 times

5 sec.

3 times

5 sec.

4 times

5 sec.

10times

5 sec.

13 times

( lights for 0.5 sec. at intervals of 0.5 sec.)

Reversing valve defective When the indoor heat exchanger temperature is too low in the heating mode or it is too high in the cooling mode.

Outdoor unit forced operation When the outdoor unit is in forced operation or balancing operation after forced operation.

Indoor unit/outdoor unit interface defective When the interface signal from the outdoor unit is interruppted.

Outdoor unit electrical components defective When the same error mode is detected 8 times within 30 minutes from outdoor unit electrical components. (However, when error is detected 8 times within two hours only for outdoor thermistor.)

Over-current detection at the DC fan motor When over-current is detected at the DC fan motor of the indoor unit.

IC401 data reading error When data read from IC401 is incorrect.

(1) Reversing valve defective (2) Heat exchanger thermistor

disconnected

(only in the heating mode).

Electrical parts in the outdoor unit.

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

(1) Indoor unit fan motor (2) Outdoor unit electrical

components (For details, operate again using remote controller and check from self-diagnosis display of outdoor unit.)

(1) Indoor unit fan lock (2) Indoor unit fan motor (3) Indoor unit control P.W.B.

IC401 abnormal

TROUBLE SHOOTING WHEN THE TIMER and DEHUMIDIFYING LAMP BLINKS

MODEL RAS-25CNH11

Perform trouble shooting according to the number of times the timer lamp on the display of the indoorunit blinks

(1) If the interface circuit is defective when the power is turned ON, the self-diagnosis indication is not displayed. (2) When indoor unit is performing self-diagnosis operation shown above, self-diagnosis lamp of the outdoor unit

blinks 9 times.

(3) If the indoor unit cannot be operated at all, check the connection of the F cable (reverse connection or dis

connection.)

(4) When timer lamp or dehumidifying lamp blinks, remote control can be used to operate for checking operation

once again.

CAUTION

Page 87

– 96 –

If checking cannot be done the first time, wait for 3 min. as it is (3 min later re-start), check the lighting condition of the self-diagnosis lamp again.

Set to the operation mode and press the Start /Stop Switch. Does the operation starts about 1 min or more ? (LD 303 lights, is mormal)

Yes

Normal

(3) Check the Refrigerating

cycle.

Check the electrical parts in the condensing unit.

Remove the compressor Connecting connector.

Compressor connecting connector

Compressor terminal board and self-diagnosis lamp.

[MODEL RAC-25CNH11]

2. Outdoor unit ( judging between “electrical parts of the condensing unit” and “refrigerating cycle”)

Page 88

– 97 –

SELF—DIAGNOSIS LIGHTING MODE :

LIT

: BLINKING :

OFF

(3) LIGHTING MODE IN THE OPERATION WITH COMPRESSOR LEAD

DISCONNECTED

(1) DISCONNECT THE CONNECTORS OF THE LEAD CONNECTED TO

THE COMPRESSOR.

(2) SET TO THE OPERATION MODE AND PRESS THE START/STOP

SWITCH.

(3) WHEN THE OPERATION ABOUT 1min. NORMALLY (LD 303 LIGHTS).

THE ELECTRICAL PARTS IN THE OUTDOOR UNIT (ESPECIALLY POWER MODULE) CAN BE THOUGHT TO BE NORMAL.

SERVICE OPERATION

CAUTION

TO COLLECT REFRIGERANT OR TO OPERATE OUTDOOR UNIT INDEPENDENTLY, TURN OFF POWER SWITCH OF THE INDOOR UNIT ONCE, THEN TURN OFF AGAIN AND SET THE SERVICE SWITCH TO COOL SIDE. (COOLING CYCLE IS SET.) TO OPERATE UNIT AGAIN, BE SURE TO RETURN SERVICE SWITCH TO NORMAL, AND TURN OFF POWER SWITCH, THEN TURN IT ON AGAIN.

BE SURE TO CHECK THAT POWER SWITCH IS TURNED OFF BEFORE SERVICING.

(NOTE 1) LD301 BLINKING 9 TIMES MODE OCCURS NOT ONLY BECAUSE OF COMMUNICATIONS ERROR, BUT ALSO WHEN FALL SIGNAL IS SENT TO INDOOR UNIT 8 TIMES WITHIN 30 MINUTES. CHECK WHETHER OR NOT DEHUMIDIFYING LAMP ON INDOOR UNIT IS BLINKING.

L D

3 0 1

RED

BLINKING

1 TIME

2 TIMES

3 TIMES

4 TIMES

5 TIMES

6 TIMES

7 TIMES

8 TIMES

9 TIMES

10 TIMES

3 0 2

RED

NORMAL OPERATION

SERVICE OPERATION

NORMAL STOP

RESET STOP

PEAK CURRENT CUT

ABNORMAL LOW SPEED ROTATION

SWITCHING FAILURE

OVERLOAD LOWER LIMIT CUT OH, FIN THERMISTOR TEMP. RISE

ABNORMAL POWER VOLTAGE

THERMISTOR ABNORMAL

ACCELERATION DEFECTIVE

COMMUNICA— TIONS ERROR

OVERLOAD

(1)

OVERLOAD

(2)

OVERLOAD

(3)

COMPRESSOR OPERATION

NOT MALFUNCTION

THIS SHOWS AN OVERLOAD. NOT MALFUNCTION.

THE ROTATION SPEED IS AUTOMATICALLY CONTROLLED TO PROTECT THE COMPRESSOR IN THE OVERLOAD CONDITION.

ONLY BLINKS WHEN LOW FREQUENCY SYNC STARTS IN THE FORCED COOLING OPERATION.

INDOOR THERMOSTAT OFF. MAIN OPERATION OFF.

WHEN STOPPED WITH POWER RESET. (NORMAL WHEN POWER HAS BEEN TURNED ON.)

1POWER MODULE 2COMPRESSOR 3CONTROL P.W.B. (DRIVE CIRCUIT. POSITION DETECTION CIRCUIT. ETC.) 1POWER MODULE 2COMPRESSOR 3CONTROL P.W.B. (DRIVE CIRCUIT. POSITION DETECTION CIRCUIT. ETC.)

OUTDOOR UNIT IS EXPOSED TO DIRECT

SUNLIGHT OR ITS AIRFLOW BLOCKED.

FAN MOTOR

FAN MOTOR CIRCUIT

INCORRECT CONNECTION OF CABLES

DISCONNECTION OF CABLE

INDOOR/OUTDOOR INTERFACE

CIRCUIT

SWITCHING FROM LOW FREQUENCY SYNC START TO POSITION DETECTION OPERATION FAILURE. UNDER THE LOWER LIMIT OF ROTATION SPEED WITH OVERLOAD CONTROL CIRCUIT OPERATED.

THERMISTOR IS OPEN OR SHORTED. (OH. OUTER TEMPERATURE. DEF. THERMISTOR)

OVERCURRENT IS DETECTED.

NOT MALFUNCTION.

POSITION DETECTION SIGNAL IS NOT INPUT DURING OPERATION.

CONTROL P. W .B. (POWER CIRCUIT, MICROCOMPUTER, ETC.)

1 POWER MODULE 2 COMPRESSOR 3 CONTROL P. W. B.

LEAK OF REFRIGERANT

COMPRESSOR

THERMISTOR CIRCUIT (OH)

1 POWER VOLT A GE 2 CONNECTION OF

REACTOR

1 LEAK OF REFRIGE RANT

2 COMPRESSOR

THERMISTOR 2CONNECTION

OF THERMISTOR DEFECTIVE

THERMISTOR CIRCUIT

OH THERMISTOR OR FIN THERMISTOR IS OPERA TED.

NO ACCBLERA TION OVER THE LOWER LIMIT OF THE ROTATION SPEED.

POWER VOLT A GE IS ABNORMALLY LOW.

COMMUNICATIONS STOPPED.

TURNING ON AND OFF ARE REPEATED AT BLINKING INTERVAL OF 0.25 SEC. IN BLINKING.

1 INTERFACE CIRCUIT 2 OUTDOOR P. W. B. 3 SERVICE SWITCH

ROTATION SPEED

SET VALUE

(3)

TIME

(2)(1)

SELF—DIA— GNOSIS NAME

[1]

DURING OPERATION

[2]

DURING STOP LD303 (RED) GOES OFF.

LD303 (RED) LIGHTS.

DETAILS

MAIN CHECK POINT

EXAMPLE OF BLINKING (5 TIMES)

2 SEC.

LIGHTS FOR 0.25 SEC AT INTERVAL OF 0.25 SEC.

...

[ MODEL RAC-25CNH11 ]

Page 89

– 98 –

YES

Is AC 220V voltage being generated between terminals A and B of the terminal board?

Is a DC 35V voltage generated between terminals C and D of the terminal board?

Is AC 220V voltage being generated at power outlet?

Check power outlet and breaker and repair defective parts.

Check power cord, power switch and terminal board. Repair defective parts.

Check the indoor/outdoor connection cable and correct the abnormal state (wrong connection, poor insertion, etc.).

Correct the connection.

Check the power circuit and peripherals and correct the defective parts.

Replace the remote controller.

Replace the light receiving unit.

Replace IC401.

Check that there is no abnormality such as a pattern short on the P.W.B., heating of parts, etc. and replace REG1. (If the output is 15V or more, it is also abnormal. Replace it.)

Check that there is no abnormality such as a pattern short on the P.W.B., heating of parts, etc. and replace REG2.

Check the reset circuit and repair defective parts.

Replace the micro computer and oscillator.

Correct the lead wires, connection of the connector.

Is a AC 220V voltage generated between terminals A and B of the terminal board in the outdoor unit?

Is a DC 35V voltage generated between terminals C and D of the terminal board in the outdoor unit?

Are jumper cables C and D connected in reverse?

Check the remote controller. (Refer to

Checking the remote controller .)

Is there poor contact of CN2, disconnection of leads, etc.?

Is DC 12V voltage being generated at both ends of C102?

Is a DC 12V voltage generated between and

of REG2?

Is a DC 5V voltage generated between o and

of REG2?

Is the air conditioner operated by pressing the temporary operation switch?

Does the timer lamp blink 13 times when the breaker is turned ON?

Is the control voltage generated normally?

Is micro computer reset input (pin

) set

to Hi ?

Does micro computer clock (pins

, 16 )

oscillate normally?

Replace the control P.W.B..

Perform a final check of operation.

Page 90

– 99 –

3. The outdoor unit does not operate (remote control command can be received).

YES

Does LD701 light when the heating operation is done with the temperature set to 32¡C using the remote controller?

Does LD701 light when the cooling operation is done with the timperature set to 16¡C using the remote controller

Are indoor/outdoor communication signals superimposed on the DC 35V of connection cable C, D?

Is an indoor transmiting signal generated at the collector of Q801?

Does LD301 of outdoor electrical parts blink 9 times?

Is LD701 turned OFF within several ten seconds after it is lit?

Perform a final check of operation.

Check the electrical parts in the outdoor unit and repair defective parts.

Check the electrical parts in the outdoor unit and repair defective parts (around the outdoor interface transmitting circuit).

Check the indoor interface transmitting circuit and repair defective parts.

Check the electrical parts in the outdoor unit and repair defective parts (around the outdoor interface transmitting circuit).

Check the heat exchanger thermistor and replace if it is defective. 〈Normal value〉20¡C ➞ approx.12.5Ω

25¡C ➞ approx.10k Ω 30¡C ➞ approx. 8k Ω

Check the room temperature thermistor and replace if it is defective. 〈Normal value〉20¡C ➞ approx.12.5Ω

25¡C ➞ approx.10k Ω 30¡C ➞ approx. 8k Ω

36kHz approx. 2Vp-p

Approx.

35V

36kHz approx. 2Vp-p transmitting

Approx.

←

Page 91

– 100 –

YES

4. Only the indoor unit fan does not operate (other functions are normal).

Is a voltage of DC25V-35V generated between pins

➀ (Blue) and ➄ (Red)

of CN10 when operated in the "HIGH" fan speed mode?

Is a pulse of about 33Vp-p generated at the callector of Q904 in the fan operation mode? Is the voltage collector of Q904 approx. 0V at this time?

Is the fan PWM (Pulse Width Modulation output (pin of micro computer set to"Hi" or is the pulse waveform output when operation mode?

Is a voltage of DC 5V generated between pins

➀

(Blue) and ➂ (Yellow)

of CN10?

Is the resistance between L901 terminals Ω or less?

Replace the indoor unit fan motor

Check whether the P.W.B. pattern is shorted and replace REG2.

Replace Q903

Replace L901

Replace Q904.

Replace Q904

Replace the micro computer.

Perform a final check of operation.

The fan cannot be stopped by the remote controller.

Is the fan PWM output (pin of the micro computer set to "Hi?

Is the voltage collector of Q904 approx. 0V?

Replace the micro computer.

4. The fan speed of the indoor unit fan cannot be changed (other functions are normal)

Page 92

– 101 –

YES

6. The air deflector cannot be moved(other functions are normal)

Are pulse signals output at pins of micro computer when the "auto air deflection" is set to ON in the fan operation mode?

Is a voltage of 15V or more generated between

➀

and G (12V line) of

REG2?

Replace the micro computer.

Check IC501 and if there is no abnormality, replace the auto sweep motor.

Replace REG1.

Perform a final check of operation.

Operate in FAN mode with HI fan speed.

Operation lamp lights once, then goes off 5 or 10 seconds later

Remove CN10 and operate in the FAN mode gain.

Operation lamp lights once, then goes off 5 or 10 second after.

Is it possible to turn indoor fan by hand easily? (turn power switch off before checking.)

Replace indoor fan.

Check if pattern of P.W.B. is not short-circuit-

Check if indoor fan is touching the chassis, etc. If it is, correct it.

7. Operation completely stops within a few seconds minutes after starting. (All displays also go off.)

Page 93

– 102 –

Yes

CHEKCING THE REMOTE CONTROL SWITCH

Is battery polarity right?

Does transmission mark light for an instant when the button is pressed?

Turn on an AM radio, bring

the remote control switch within

15 cm of the radio, and press

the Start / Stop switch.

Does the radio buzz noisily?

Check the remote control signal

receiving P. W. B.

If it is good, check the main P. W. B.

Install the battery in the right polarity.

Replace the battery.

Check the LED (D1) with a multimeter.

Check functions again.

If it does not work, replace

the remote control switch.

[AM radio]

"Buzz"

Within 15 cm

Page 94

– 103 –

Light receiving unit

Regulated power supply

Electrolytic capacitor 100µ10V

1k 1/4W Carbon resistor

LED

DC5V

Viewed from the Light receiving unit terminal side

Remote control switch

Video camera



(0V)

(5V)

Ultra redray test card

Sensible area

Within 2 cm

The sensible area should flash in orange when you operate the remote control unit if is good.

You can check the remote control switch by other methods as explained below.

(1) Using a video monitor

Connect a video camera to a TV and aim at the remote control switch. If infrared rays are emitted from the switch, you will see a flash in violet on the monitor screen.

(2) Using a Checker

You can make a checker by yourself. Its circuit diagram is shown below.

(3) Using the test card

Page 95

– 104 –

YES

[The air conditioner does not operate at ail or cannot be operated correctly]

Is 220V supplied to the A,B terminal?

Is chattering sound of relay heard?

Is the 15A fuse normal?

Is the power circuit normal?

Refer to the power circuit for detals.

Is 35V being applied between C and D?

Because of reverse connection of C/D line, chattering occurs at I/F relay.

Correct connection of C/D line.

Be careful since the other parts could also be defective hen the 15A fuse is blown. Mainly, diode stack, smoothing capacitor, power modure, etc.

Replace defective parts.

[MODEL RAC-25CNH11]

Checking the electical parts

in the outdoor unit.

Page 96

– 105 –

YES

Is switching power circuit normal? Is 3A fuse normal?

Operate the outdoor unit according to the "Operation of the outdoor unit indepndently".

What condition does the selfdisgnosis lamp indicate?

Are cords for connecting terminal board, reactor, diode, smoothing capacitor, etc. connected correctly

Securely insert them if loosened or disconnected.

Is power circuit of compressor normal? Refer to "Power circuit" for details.

Is DC 35V output at C and D terminals? (DC 33V - 40V is output in the normal state.)

LD301: Blinking 10 times.

Half voltage error

Replace defective parts.

If 3A fuse has been blown, Q1, switching transformer, ZD3, etc. may be defective.

LD301: Blinks 9 times.

Communications error

YES

Page 97

– 106 –

Interface relay

Coil terminal

Contact terminal

YES

Is there DC35V output at both ends of C67?

There are defective parts between brown/red jumper wire and C/D line.

Is DC 12V applied to both ends of the control side (coil terminals) of the interface relay?

Replace the interface relay.

Is a voltage (10V or more) generated between the connection terminals of the interface relay?

Check the interface circuit.

YES

There are defective parts between the 12V output of the switching power supply on the control P.W.B. and the interface relay. (Also check the solder-touch, etc.)

Page 98

– 107 –

Is the power module normal?

YES

Is the micro computer drive circuit PS-HIC normal?

Is the connector of the thermistor disconnected?

Be careful not to forget to

re-connect after servicing.

Is the continuity of thermistor normal?

Is the thermistor circuit normal?

Replace parts in the thermistor circuit.

Replace the thermistor.

Connect the thermistor connector.

Replace defective parts.

Replace the power module.

Perform continuity check of the leads and pattern according to the P.W.B. diagram and circuit diagram.

LD301 : Blinks 8 times.

Acceleration defective

LD301 : Blinks 7 times.

Thermistor abnormal

Page 99

– 108 –

YES

LD301: Blinks 6 times.

OH thermistor temperature rises

LD301: Blinks 5 times.

Overload lower limit cut

LD301: Blinks 4 times.

Switching failure

LD301: Blinks 3 times.

Abnormally low rotation speed

Is the thermistor circuit normal?

Leakage of refrigerant or compressor defective.

Replace the control P.W.B.

Is the power module normal?

Are position detection circuit and drive circuit PS-HIC normal?

Replace parts in the thermistor circuit.

Replace defective parts.

Check the continuity of replaced parts.

Replace the power module.

Replace defective parts.

Perform continuity check of the leads and pattern according to the P.W.B. diagram and circuit diagram.

Page 100

– 109 –

LD301: Blinks 2 times.

YES

Peak current cut

LD301: Blinks 1 times.

Reset stop

Is the power module normal?

Is the drive circuit normal?

Replace the power module.

Replace defective parts.

Operate the air conditioner again. Does it operate normally?

Perform a final check of operation.

Is the reset circuit normal?

17 of the micro computer is

approx. 5V in the normal state