Samsung AD26B1C13 User manual

SERVICE Manual
CONTENTSAIR CONDITIONER
1. Installation
2. Disassembly and Reassembly
3. Troubleshooting
4. Exploded Views and Parts List
5. Refrigerating Cycle Block Diagrams
6. Wiring Diagrams
7. Schematic Diagrams
ROOM AIR CONDITIONER
INDOOR UNIT
AD26B1C13
AD18B1C09
OUTDOOR UNIT
UD26B1C2
UD18B1C2
E DB98-05645A(1)
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1. Installation
1-1 Refrigerant Refill Procedure
INDOOR
A-UNIT
INDOOR
B-UNIT
• Piping length and the height
Additional refrigerant charge
(R22,g)
• When length of the pipe is
over 5u by the unit, you
should charge
the refrigerant Formulas
A-UNIT : 20gx(La-5)/m
B-UNIT : 20gx(Lb-5)/m
(La:the length of A-unit’s
pipe Lb:the length of
B-unit’s pipe)
A-UNIT 1/4” 1/2” 15m(49ft 3in) 7m(23ft)
B-UNIT 1/4” 1/2” 15m(49ft 3in) 7m(23ft)
A-UNIT 1/4” 3/8” 15m(49ft 3in) 7m(23ft)
B-UNIT 1/4” 3/8” 15m(49ft 3in) 7m(23ft)
Max.piping
length
A
Max
height
B
LIQUID GAS
Pipe Size
AD26B1C13
AD18B1C09
INDOOR UNIT
OUTDOOR UNIT
A
B
If connecting pipe of more than 5 metres is installed, additional refrigerant should be charged by extra
metre. You don’t have to charge additional refrigerant up to 5 metres of connecting pipe.
1. Remove the valve stem cap and service port of 3-way
valve.
3. Operate the unit at the cooling mode.
4. Slowly open the valve of the low pressure side of
Manifold gauge counterclockwise until the low pressure
of manifold gauge indicates 4.8 to 5.5 kg/cm2(68 a
78psi) at the high cool operation (1-unit operation) and
the standard temperature.
It is recommend that refrigerant should be slowly put in.
If the refrigerant is put in too quickly, compressor will be
damaged.
5. Stop operation of the air conditioner.
6. Disconnect the charge hose of manifold gauge.
7. Close the cap of each valve.
2. Connect the charging hose of low pressure side of
Manifold gauge to the packed valve having a charging
port(1/2” Packed valve) as shown at the right figure.
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1-2 “Pump down” Procedure
Relocation of the air conditioner
1. Carry out the pump down procedure
(refer to the details of ‘pump down’).
2. Remove the power cord.
3. Disconnect the assembly cable from the
indoor and outdoor units.
4. Remove the flare nut connecting the indoor
unit and the pipe.
At this time, cover the pipe of the indoor
unit and the other pipe using a cap or vinyl
plug to avoid foreign material entering.
5. Disconnect the pipe connected to the out-
door unit.
At this time, cover the valve of the outdoor
unit and the other pipe using a cap or vinyl
plug to avoid foreign material entering.
6. Make sure you do not bend the connection
pipes in the middle and store together with
the cables.
7. Move the indoor and outdoor units to a new
location.
8. Remove the mounting plate for the indoor
unit and move it to a new location.
2-Way Valve
Cap
3-Way Valve
• Refer to this procedure when the unit is relocated.
1. Confirm that both the 2-way and 3-way valves are set to
the open position.
(1) Remove the valve stem caps.
(2) Be sure to use a hexagonal wrench to operate the Gas
side valve stems.
2. Operate the unit for 10 to 15 minutes.
3. Stop operation and wait for 3 minutes, then connect the
charge set to the service port of the 3-way valve.
(1) Connect the charge hose with the push pin to the ser-
vice port.
4. Air purging of the charge hose.
(1) Open the low-pressure valve on the charge set slightly
to air purge from the charge hose.
5. Set the liquid side 2-way valve to the closed position.
6. Operate the air conditioner at the cooling cycle and stop
operation immediately after setting the 3-way valve to the
closed position when the gauge indicates 0 kg/cm2G.
If the unit can not be operated at the Cooling Mode(weater
is rather cool), operate the unit at the Trubo Mode.
So that the unit can be operated.
7. Disconnect the charge set, and mount the both 3-way
valve’s stem nuts and the service port cap.
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2. Disassembly and Reassembly
2-1 Indoor Unit
Stop operation of the air conditioner and remove the power cable before repairing the unit.
No Parts Procedure Remark
Front Grille1 1) Stop the air conditioner operation and block the
main power.
2) Separate tape of front panel upper.
3) Contract the second finger to the left, and right
handle and pull to open the inlet grille.
4) Take the left and right filter out.
5) Loosen one of the right fixing screw and sepa-
rate the terminal cover.
6) Loosen three fixing screws of front grille.
7) Pull the upper left and right of discharge softly
for the outside cover to be pulled out.
8) Pull softly the lower part of discharge and push
it up.
Caution;
Assemble the front panel and fix the
hooks of left and right.
*Taking off the deodorizing filter.
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No Parts Procedure Remark
Electrical Parts
(Main PCB)
Ass’y Tray Drain.
Heat Exchanger
Fan Motor and
Cross Fan
2
3
4
5
1) Do “1”above.
2) Take all the connector of PCB upper side out.
(Inclusion Power cord)
3) Separate the outdoor unit connection wire from
the terminal block.
4) If pulling the Main PCB up. it will be taken out.
1) Do “1”, “2”, above.
Separate the drain hose from the extension
drain hose.
2) Pull tray drain out from the back body.
1) Do “1” and “2”, “3”, above.
2) Loosen two fixing earth screws of right side.
3) Separate the connection pipe.
4) Separate the holder pipe at the rearside.
5) Loosen the three fixing screws of right and left
side.
6) Lifting the heat exchanger up a little to push the
up side for separation from the indoor unit.
1) Do “1”, “2”, ”3”, “4”, above.
2) Loosen the fixing two screws and separate the
motor holder.
3) Loosen the fixing screw of fan motor.
(By use of M3 wrench)
4) Separate the fan motor from the fan.
5) Separate the fan from the left holder bearing.
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2-2 Outdoor Unit
No Parts Procedure Remark
Cabinet
Fan Motor
&
Propeller Fan
1) Turn off the unit and remove the power cable.
2) Remove the top cover.
3) Remove the control box cover.
4) Unplug the ass'y cable.
5) Remove the cabi-side.
6) Remove the cabi-front.
* When you assemble the parts, check if the
each parts and electric connectors are fixed
firmly.
1) Do Procedure “1” above.
2) Remove the nut flange.
(Turn to the right to remove as it is a left turned
screw)
3) Disassemble the propeller fan.
1
2
<UD18B1C2>
<UD26B1C2>
<UD26B1C2>
<UD18B1C2>
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1) The input voltage should be rating voltage ±10% range.
The airconditioner may not operate properly if the voltage is out of this range.
2) Is the link cable linking the indoor unit and the outdoor unit linked properly?
The indoor unit and the outdoor unit shall be linked by 5 cables.
Check the terminals if the indoor unit and outdoor unit are properly linked by the same number
of cables. Otherwise the airconditioner may not operate properly.
3) When a problem occurs due to the contents illustrated in the table below it is a symptom not
related to the malfunction of the airconditioner.
3. Troubleshooting
3-1 Items to be checked first
NO Operation of air conditioner
1 The STD operation indication LED blinks when a
power plug of the indoor unit is plugged in for the first time.
2 In a COOL operation mode, the compressor does not
operate at a room temperature higher than the setting
temperature that the IN DOOR FAN should operate.
In a HEAT operation mode, the compressor does not
operate at a room temperature lower than the setting
temperature that indoor fan should operate.
3 Fan speed setting is not allowed in AUTO or DRY mode.
4 Compressor stops operation intermittently in DRY mode.
5 Compressor of the outdoor unit is operating although it is
turned off in a HEAT mode.
6 Timer LED only of the indoor unit lights up and the
air conditioner does not operate.
7 The compressor and indoor fan stop intermittently in HEAT
mode.
8 Indoor fan and outdoor fan stop operation intermittently in
a HEAT mode.
9 The compressor stops intermittently in a COOL mode or DRY
mode, and fan speed of the indoor unit decreases.
It indicates power is on. The LED stops blinking if the operation
ON/OFF button on the remote control unit is pushed.
In happens after a delay of 3 minutes when the compressor is
reoperated. The same phenomenon occurs when a power is on.
As a phenomenon that the compressor is reoperated after a delay
of 3 minutes, the indoor fan is adjusted automatically with refer-
ence to a temperature of the air blew
The speed of the indoor fan is set to LL in DRY mode.
Fan speed is 5 steps is selected automatically in AUTO mode.
Compressor operation is controlled automatically in DRY mode
depending on the room temperature and humidity.
When the unit is turned off while de-ice is activated, the com-
pressor continues operation for up to 9 minutes (maximum) until
the deice is completed.
Timer is being activated and the unit is in ready mode.
The unit operates normally if the timer operation is cancelled.
The compressor and indoor fan stop intermittently if room temper-
ature exceeds a setting temperature in order to protect the com-
pressor from overheated air in a HEAT mode.
The compressor operates in a reverse cycle to remove exterior ice
in a HEAT mode, and indoor fan and outdoor fan do not operate
intermittently for within 20% of the total heater operation
The compressor stops intermittently or the fan speed of the indoor
unit decreases to prevent inside/outside air frozen depending on
the inside/outside air temperature.
Explanation
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Display
Standard Timer Nature Power
(GREEN)
X
(GREEN)
X
X
(GREEN)
(GREEN)
X
X
X
X
X
X
X
X
X
X
X
X
X
Restore from power failure (input initial power)
Indoor unit Room sensor Error (open or short)
Indoor unit heat exchanger temperature sensor Error (open or short)
Indoor fan malfunctioning (for speed is below 450rpm)
In case that the communication between the indoor unit and outdoor unit is not made
for 60 seconds
Outdoor sensor Error (open or short)
- Outdoor sensor
- Pipe sensor A, B
The malfunction ot 4way valve in heat mode operation.
Self Diagnosis
4) Indoor unit observes operation condition of the air conditioner, and displays self diagnosis details
on the display panel.
NO
1
2
3
4
5
6
7
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3-2 Checking and Testing Operations (Outdoor Unit)
To complete the installation, perform the following checks and tests to ensure that
the air conditioner is operating correctly.
1. Review all the following elements in the installation:
• Installation site strength
• Piping connection tightness to detect any gas leakages
• Connection wiring
• Heat-resistant insulation of the piping
• Drainage
• Earthing wire connection
• Correct operations (follow the steps below)
• Room select switch in the indoor unit
2. Apply the power to the outdoor unit.
- Check the fuse (250V~, 5A) : The fuse is open when the power line (L1, N2) is short.
C
a
b
TEST OPERATING
CBA
3. Check the connection of PCB communication of outdoor unit.
(Check whether the red LED of outdoor unit PCB is flickering.)
• The communication lamp is flickering after the display of each
unit on the outdoor PCB display part. (every one second).
LED is not flikering, if the connection is bad or the room select
switch is located in the wrong position.
- LED lamp (red) flickering after display of A (0.5 sec)
- LED lamp (red) flickering after display of b (0.5 sec)
- LED lamp (red) flickering after display of C (0.5 sec)
Note : PCB switch “C” is used for triple split multi air conditioner.
Result : If all of three units display lamps are flickering, the connection
wires and the room option connections are good.
OUTDOOR UNIT
A : PCB display
B : Red LED
C : PCB switch
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4. Check the test operation status by pressing the PCB switch
4. S/W-A and S/W-B of outdoor unit.
4. • Check the operation status by pushing the switch one at time.
4. • Perform the test operation only for the unit selected last.
4. • Check the pipe pressure and the other operation status during the test operation.
4. • Check items when the error occurs during the test operation (each unit)
- Check there is enough refrigerant.
- Check pipe connections.
If the lamp is not flickering, check as follows:
A. Check the display part of indoor unit of each unit (A,B) after outdoor unit PCB switch S/W-A is on.
A. Check the status of each unit indoor room select switch.
A. (Adjust the select switch suitable to the unit A, B.)
A. - A unit : STANDARD LED on, TIMER LED flickering
A. - B unit : STANDARD LED on, TIMER and NATURE LED flickering
A. - C unit : STANDARD LED on, TIMER and NATURE, POWER LED flickering (In case of triple
split multi air conditioner)
UNIT
A
B
CLamp ON
STANDARD TIMER NATURE POWER
Lamp OFF Lamp Flasher
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DISPLAY EXPLANATION
Outdoor sensor error (Short/Open)
Outdoor A cond pipe sensor error (Short/Open)
Outdoor B cond pipe sensor error (Short/Open)
Outdoor C cond pipe sensor error (Short/Open)
A unit test operation error
B unit test operation error
C unit test operation error
A unit test communication error
B unit test communication error
C unit test communication error
A,B,C unit all communication error
A room test operation OK
B room test operation OK
C room test operation OK
Communication unit number display : A unit
Communication unit number display : B unit
Communication unit number display : C unit
(In case of triple split multi air conditioner)
Refrigerant leaks
High temperature of the A cond
High temperature of the B cond
REMARK
Be sure to check after applying the power to the outdoor unit.
Be sure to check during the test operation.
Display of power application.
Display 4 minutes after the COMP is on.
•Normal operation
•Unit A,B and C are changed every one second.
•The communication lamp is flickering after display of each unit.
•(possibility to check the communication status)
•During the test operation the unit under test is on and off every 0.25s.
Display when the test operation finishes.
• When the pipe temperature difference of indoor unit
• (pipe temperature 4 minutes before - Actual pipe temperature)
• is less than 5˚C.
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3-3 Fault Diagnosis by Symptom
3-3-1 No Power (completely dead)-Initial diagnosis
1) Checklist :
(1) Is input voltage normal?
(2) Is AC power linked correctly?
(3) Is output voltage of DC regulator IC KA7805 (IC02) normal? (4.5VDC-5.5VDC)
2) Troubleshooting procedure
Replace
PCB display
Is DC voltage of PCB
display normal?
Remove power cord and plug in
again in approx. 5 seconds
Is operation lamp blinking?
Does operation start when
run/stop button on the remote
controller unit pushed?
Is transmission display of the
remote controller unit blinking?
Is "beep"sound heard from the
main unit?
Is DC voltage of the PCB module
normal?
5VDC Is voltage of #60 (indoor fan)
of the micom normal?
Is rating voltage ±10%
range applied to the
primary side (~,~)
of the “BD71”
•Check linkage between
power cord and
terminal tap
•Check fuse
Is 14~18VAC appear in
the secondary side (+, -)
of “BD71”
Replace
SMPS PARTS
YES
NO YES
NO
YES
YES
YES
NO
YES
YES
DC5V
10ms
10ms
250ns
NO
OK
YES
YES
YES
YES
NO
NO
YES Normal
Refer to remote control
unit fault diagnosis
Replace PCB module.
Is output voltage of ICO2 normal?
Check connections
compressor 4-way
valve, outdoor fan and
indoor fan.
DC12V
Is voltage at SS71(indoor fan)
Replace RY71,
RY73, RY72 and
SS71
NO
NO
NO
Is voltage output terminal of
TLP180(PC02) normal?
Replace ICO2
Check PCB pattern.
Replace main PCB.
Replace TLP180(pc02)
Replace micom
Is voltage at #52 terminal of the
micom normal?
Are voltage at #48 and #49 of the
micom normal?
NO
NO NO
YES
NO
NO
NO
YES
OK
Is operation normal?
Replace resonator (X301)
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3-3-2 When the power voltage is not available
1) Inspection items
(1) Is the power voltage is normal? (The rating voltage ±10% range)
(2) Is the power cord is correctly connected and is the contact good?
(3) Does the sound “ting” come out with the operation lamp (green) flickering when the
power is applied?
If it is not flickering, do inspect and repair in accordance with the following inspection
sequence.
2) Inspection sequence
Apply the power
Is the operation lamp of
indoor unit on when the
operation /stop button of
remote controller is
pressed?
Is the communication
signal of remote
controller surely sent
and received ?
Is there no problem
between the connector of
Ass’y display PCB and the
receiving module?
Replace of
Ass'y display PCB
Is the fuse (F701, 250V, 3.15A) of PCB open?
Is the voltage at Socondary side of transformer
of PCB (TN71)? (AC15V~AC25V)
Is the output voltage of voltage regulator
IC (KA 7812) DC 10V and 12V?
Is the output voltage of electrostatic voltage
regulator IC (KA 7805) DC 4.5 V - 5.5 V?
Replace the main PCB of indoor unit
Repair and replace the power
source rectifying diode (D101-
D105) and KA7812.
KA7805 is out of order - replace
Transformer is out of
order - replace
Replace the fuse (250V, 3.15 A)
Is the outdoor power connected normally? Check of the installation
method and electrical circuit
No trouble
(normal)
Check of remote
controller
Normal
Is the operation lamp flickering with the
sound of “ting”?
YES
NO
NO
YES
YES
NO
NO
YES
NO
YES
YES
YES
NO
NO
NO
YES
NO
YES
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3-3-3 No Power (Outdoor unit)
1) Inspection items
(1) Á Is the power source normal (The rating Voltage ±10% range)?
(2) Is the outdoor power connected normally? ((1) of terminal : L, (2) of terminal : N,
(3) of terminal : communication) ?
(3) Check whether the display of outdoor PCB(SEG1) is shown in the order of A- B - C when the
power is applied.
If the display (SEG 1) is not shown the inspection and repair shall be performed in the sequence
of the following:
2) Inspection sequence
Normal of
outdoor PCB
Replace the fuse
(F701) 250V 3.15A.
Replace the
transformer
Assemble the transformer
in the normal way.
Put the power off and put it on after
5 seconds.
Replace the outdoor unit Ass'y main PCB.
Reinstall the power cord and
communication line with the
reference of installation manual.
Replace the fuse F101
(250V 2 A).
Replace the IC 02 (KA7805)
Check and Replace the rectifying
diode of power side
(D101 - D104) and KA 7812.
After watching the display of
PCB board, assemble the
color and shape of housing
correctly as follows:
Is the display of PCB shown in the
sequence of A-B-C?
Check the
communication of
PCB and whether
the LED 1 is contin-
uously flickering.
Are the power cord ((1) L, (2) N) and
communication line (3) of outdoor terminal
block connected correctly?
Is the terminal of PCB terminal (RY71, 72, 73)
are assembled in the correct position?
Is the fuse open? (F701)
Is the fuse (F101, 250V 2 A) blown out?
Check whether the output voltage of
IC01 (KA 7812) is DC 12V.
Check whether the output voltage of
IC02 (KA 7805) is DC 5V.
Insert the primary side of power transformer
in the terminal GT01 and then is the voltage
of secondary side normal? (AC 15V- AC 25V)
Measurement of resistance
of power transformer
Are they as follows?
1st side 190 ~ 210Ω
2nd side 0.9 ~ 1.1Ω
BLK
WHT
BLK
RED RED
WHT
YES YES
NO NO
YES
YES
NO
YES
NO
YES
NO NO
YES
YES
YES
NO
NO
YES
NO
NO
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3-3-4 When the fan of indoor unit does not operate
1) Inspection items
(1) Is the power voltage normal?
(2) Is the connector of indoor fan with the good contact? (CN73)
(3) Is the soldering status of running condenser (CR71) with the good contact?
(4) Is connector of the Hall IC with the good contact (CN 43) ?
(5) Is the indoor fan rotating when it is under operation mode?
(6) Is the FAN LED (green) flickering when the indoor fan stalled (for more than 15 seconds) and
the trouble condition of speed detecting part?
Put the power off and put it on after 5 seconds.
Replace the indoor unit PCB Ass'y due to the
Micom defect.
If the power is not available
(indoor unit), item no 3-3-1.
Replace of indoor unit PCB Ass'y.
Replace the IC 06 (KID 65003)
and SS71(G3MB202pl).
Replace Q401 (Ksc 945Y).
Replacement of
indoor unit fan motor.
Is the operation lamp flickering for 3 minutes and
then put off?
Is AC 120V and higher shown across the indoor fan
connector (CN73) ?
Is the type of MICOM (IC 04) Pin no.
63 old type ?
120Hz
If the operation /stop button of the remote controller
is pressed, is the operation lamp flickering and then is
the indoor fan rotating after 5~6 seconds?
Error occurs after the
indoor unit fan motor is
rotating for 15 seconds?
(FAN Lamp flickering)
YES
YES
YES
YES
YES
YES
YES
YES
NO
NO
NO
NO
NO
NO
Is the pin no. 12 of IC 06 (KID 65003)
the old type?
Is the pin no 25 of MICOM
the old type?
120Hz
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3-3-5 When the outdoor unit fan does not operate
1) Inspection items
(1) The outdoor unit fan motor operates only when the operating conditions are satisfied and is selected
by the RY74(LOW) and PY75(HI) to rotate.
(2) Is the power voltage normal?
(3) Is the contact of outdoor unit fan motor (CN 73) good?
(4) Is the winding resistance of outdoor unit fan motor 58Ωat Hi side and 143Ωat low side?
(5) The outdoor unit fan motor operates with Hi at over 28°C and low at below 26°C during the cooling
operation, and operates with Hi at below 14°C and low at over 15°C during the heating operation.
2) Inspection sequence
* Operating specification of the FAN of outdoor unit
(1) When the COMP is under the COMP ON condition during the cooling and heating operation,
Hi or LOW operation is selected according to the temperature condition of outdoor room.
(2) When A room and B room are mixed to operate , it is always under low operation.
(3) Perform the comp ON/OFF control in the dry mode.
(4) When it is under the operation of anti-freezing, overload protection, defrost operation, it may
be Low, high or Off.
(5) Hi = High speed, Low = Low speed
Apply the power to the outdoor unit and operate the indoor unit.
Normal
Normal (operation off)
Normal
Check the winding resistance of outdoor unit fan
motor winding resistance →Replace
Contact bad of RY 74(Low), RY 75(High)
→Replace
Defect of IC06 output
→Replace
Defect of IC 04(MICOM) - replace the IC 04
or PCB ass’y
Is the indoor unit under operating conditions?
Is it operating in the High speed?
Is no. 11 ( 12) of IC 06 at low? (DC 0.7 V)
Is pin no. 48(49) of IC 04 (MICOM) at High (DC 5 V)?
Is the outdoor unit fan motor under the operating
conditions?
Is the voltage shown across the connector (1)↔(3) ((1)↔(5))
(the rating voltage ±10% range)?
YES YES
YES
YES
YES
YES
NO
NO
NO
NO
NO
NO
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3-3-6 When the UP/DOWN Louver Moter Does Not Operate. (Initial Diagnosis)
1) Checklist :
(1) Is input voltage normal?
(2) Is the UP/DOWN louver motor properly connected with the connector (CN61)?
2) Troubleshooting procedure
Remove power cord and plug in again in approx. 5 seconds.
Is operating lamp blinking?
Does operation start when swing button of
the remote control unit pushed?
Voltage at pin #33 ~ #36 of micom (ICO4) change?(Squarewave)
Volatge at pin #13, #14, #15, #16 of IC05 (KID65003)
change?(Squarewave)
UP/DOWN louver motor is faulty.
Driver IC05 (KID65003) is faulty.
Micom (IC04) is faulty.
Normal
Check as in the procedure "No Power parts".
Refer to page 11.
YES
YES
NO
NO
NO
YES
YES
YES
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3-3-7 If Operation By Remote Control Unit Is Impossible. (Initial Diagnosis)
1) Troubleshooting procedure
Remove power cord and plug in again approx. 5 Seconds
Is operation lamp blinking? Check as in the procedure “NO Power parts”.
Refer to page 11.
Normal
Replace battery.
LCD is faulty.
Replace button.
Micom is faulty.
Receiver module is faulty.
Q601(C4375Y) or Q602(C1623Y) is faulty.
IR LED(CL-1L5EU) is faulty.
“ “ sound heard from the indoor unit when ON/OFF
button on the remote control unit pushed?
Voltage of battery less than 2.5V (Remote Control Unit)?
LCD display status of REMOCON normal?
Voltage at PIN #30 of Remocon Micom change?
Voltage at collecter of Q601 or Q602 change?
Voltage at pin #26 of micom (IC04) change (INDOOR UNIT)?
Micom (IC04) is faulty.
Transmission display lamp ( ) blinking when
ON/OFF button on the remote control unit pushed?
NO
YES
YES
NO
NO
NO
NO
NO
YES
YES
YES
YES
YES
NO
NO
YES
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3-3-8 When the 4 way valve (A,B) is not operating
1) Inspection items
(1) Are the 4 way valve A and B under the operating conditions?
(When the COMP A (4 way valve A ) and COMP B (4 way valve B) are on during the
heating operating)
(2) Is the power voltage normal?
(3) Is the connecting of 4 way valve A (CN 75) and B (CN 76) good?
2) Inspection sequence
*4 way valve operating conditions
(1) During the defrost control, put the 4 way valve A(B) off.
(2) During the heating operation put the 4 way valve A(B) on.
(3) The changeover of heating to cooling : put the 4 way valve off immediately (in case of B and C room).
(4) The changeover of cooling to heating : it is on after 170 seconds delay.
Put off the outdoor unit power and put it on again after 5 seconds.
Select the heating operation of A(B) room by the remote controller.
Normal
Keep 4 way valve off.
Normal
Defect of RY 76 (RY 77) contact and coil
→Replace the Relay
Defect of IC 06 (IC 07 ) output →Replace
Defect of IC 04(MICOM) - replace the IC 04
or PCB ass’y
Has 3 minutes passed after selection of A(B) room heating?
Is the 4 way valve A(B) on?
Is the pin no 47(46) of IC 04 ( MICOM) at high (DC 5V) ?
Is the 4 way valve A (B) under operating conditions?
Is the voltage shown across the 4 way valve A(B) connector
(CN 75, CN 76) ?
YES YES
YES
YES
YES
NO
NO
NO
NO
NO
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3-3-9 When the compressor does not operate
1) Inspection items
(1) Is the COMP A under the operating conditions? (cooling operating of A, B(C) room)
(2) Is the power voltage normal? (the rating voltage ±10% range)
(3) Are the connector connection of COMP A(RY 72, 73) and B(RY 71) good?
(4) The COMP A(B) is operated on and off in accordance with the operating conditions of indoor
unit of A (B. C) room.
2) Inspection sequence
* Comp A (B ) operating conditions
(1) Comp A : Comp on /off control in accordance with the A room during the heating and cooling
indoor unit operation
(2) Comp B : Comp on /off control in accordance with the B(C) room during the heating and cooling
indoor unit operation
* Comp A(B ) power measuring terminal
(1) Comp A measuring ; RY 73 (4) ´ RY 72 (4)
(2) Comp B measuring ; RY 71 (4) ´ RY 72 (4)
(3) Power input ; RY 72 (3) ´ RY 73(3)
Apply the outdoor power and operate the indoor unit A(B, C)
in the cooling mode.
Normal (comp A (B ) off)
Keep Comp A (B) off
*Refer to the power measuring terminal
Normal
Defect of comp A (B) and running condenser
→Replace
Defect of Ry 72, 73 (Comp B) and Ry 71(comp A)
contact and coil →Replace
Defect of IC 06 output
→Replace
Defect of Ic 04 (micom)
→Replace
Has 3 minutes passed COMP A(B) after the power initial
and COMP on/off
Is comp A (B) on?
Is the voltage of pin no. 14, 13( 15) at low
(DC 0.7V)?
Is the voltage of pin no. 50, 51 (52) of IC 04 (micom) at
high (DC 5V)?
Is comp A (B ) under the operating condition?
Is the voltage (the rating voltage ±10% range) shown
across the terminal of Comp A(B) power applied?
YES
YES
YES
YES
YES
YES
NO
Normal (comp A (B) off)
Is the comp A under the operating condition?
YES
NO
NO
NO
NO
NO
NO
RED
BLK
RY72
RY71
BLK
WHT
RED
WHT
RY73
(3) (4)
(3) (4)
(3) (4)
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