Sharp AE-X3M18JR User manual

SERVICE MANUAL
AE3XM18JR
S1804AEX3M18J
AE-X3M18JR
Parts marked with " " are important for maintaining the safety of the set. Be sure to replace these parts with specified ones for maintaining the
safety and performance of the set.
This document has been published to be used for
after sales service only.
The contents are subject to change without notice.
CHAPTER 1. SPECIFICATIONS
[1] SPECIFICATION............................................ 1-1
[2] EXTERNAL DIMENSION............................... 1-2
[3] CAPACITY TABLE ......................................... 1-3
[4] ELECTRICAL PARTS .................................... 1-3
[5] WIRING DIAGRAMS...................................... 1-4
CHAPTER 2. EXPLANATION OF CIRCUIT AND OP-
ERATION
[1] BLOCK DIAGARM ......................................... 2-1
[2] FUNCTIONS .................................................. 2-2
[3] ACTIVE FILTER CIRCUIT ............................. 2-4
[4] EXPLANATION OF IPM DRIVE CIRCUIT........ 2-6
CHAPTER 3. FUNCTION AND OPERATION OF PRO-
TECTIVE PROCEDURES
[1] PROTECTIVE FUNCTIONS AND OPERA-
TIONS ............................................................ 3-1
[2] TROUBLESHOOTING GUIDE ......................3-2
CHAPTER 4. REFRIGERATION CYCLE
[1] REFRIGERATION SYCLE.............................4-1
[2] REFRIGERANT PIPE INSTALLATION
WORKS .........................................................4-2
CHAPTER 5. DISASSEMBLING PROCEDURE
[1] OUTDOOR UNIT...........................................5-1
Parts List
TopPage
CONTENTS
MULITI SPLIT TYPE
ROOM AIR CONDITIONERS
(OUTDOOR UNIT)
MODEL
In the interests of user-safety (Required by safety regulations in some countries)
the set should be restored to its original condition and only parts identical to those
specified should be used.

AEX3M18JR
1 – 1
AEX3M18JR ServiceManual

CHAPTER 1. SPECIFICATIONS
[1] SPECIFICATION
NOTE: The condition of star “✩“marked item are ‘ISO5151’:
*: Representative connection
ITEMS INDOOR UNIT
AY-XPM7FR/9FR/12FR
OUTDOOR UNIT
AE-X3M18JR
Cooling capacity kW
3-INDOOR OPERATION 7K & 7K & 7K 5.2 (2.2 – 7.2)*
Heating capacity kW
3-INDOOR OPERATION 7K & 7K & 7K 6.8 (2.2 – 8.4)*
Moisture removal Liters/h 2.0
✩Electrical data
Phase Single
Rated frequency Hz 50
Rated voltage V 230V
Rated current Cool A 6.5 (2.0 – 11.7)*
Heat A 7.6 (1.9 – 11.4)*
Rated input Cool W 1410 (430– 2560)*
Heat W 1660 (420 – 2480)*
Power factor Cool % 95
Heat % 95
Compressor
Type Hermetically sealed DC twin rotary
Model DA130A1F-28F
Oil charge Ester oil VG74
Refrigerant system
Evaporator Silt Fin and Grooved tube type
Condenser Corrugate Fin and Grooved tube type
Control Expansion valve
Name of refrigerant R410A
Refrigerant volume 1800g
Noise level (at cooling) dB(A)
High/Med/Low
7FR: 37/34/28
469FR: 39/36/28
12FR: 40/37/29
Fan system
Drive Direct drive
Air flow quantity (at cooling) .
m3/min.
High/Med/Low
7FR: 8.0/7.4/5.0
339FR: 8.6/7.9/5.6
12FR: 9.0/8.6/6.1
Fan Cross flow fan Propeller fan
Connections
Refrigerant coupling Flare type
Refrigerant tube size Gas, Liquid 3/8”, 1/4”
Maximum length (per unit) m 25
Maximum length (total) m 50
Maximum charge-less length m 40
Maximum height difference m 10
Drain joint mm O.Dφ18
Others
Safety device
Compressor: Thermistor
Fan motors: Thermal fuse (indoor unit).
Thermal protector (Out door unit)
Fuse, Micro computer control
Air filters Anti-mold polypropylene net of injection type (Washable)
Net dimensions Width mm 790 950 (890+60)
Height mm 278 645
Depth mm 198 323 (290+33)
Net weight kg 9 56

AEX3M18JR
1 – 2
[2] EXTERNAL DIMENSION
117
320
24
24
52
284
645
621
210
151
940 323
890 290
50 5
570 170
52
5274
179
320
645
527
890
950
60

AEX3M18JR
1 – 3
[3] CAPACITY TABLE
COOLING CAPACITY TABLE
HEATING CAPACITY TABLE
[4] ELECTRICAL PARTS
Recommended Combination
Outdoor Units Indoor Units
AY-XPM7/9/12FR, GS-XPM9/12, GS-XPM7/9/12FR
AE-X3M18JR
999
12 7 7
997
977
777
Operating
Status
Combination of Indoor
Units
Cooling Capacity (kW) Running Current (A) Power Consumption (W)
A B C A B C RATING (Min. - Max.) RATING (Min. - Max.) RATING (Min. - Max.)
3-Room
09 09 09 1.7 1.7 1.7 5.2(2.2 - 7.2) 6.5 (2.0 - 11.7) 1410 (430 - 2560)
12 09 07 2.2 1.7 1.3 5.2(2.2 - 7.2) 6.5 (2.0 - 11.7) 1410 (430 - 2560)
12 07 07 2.4 1.4 1.4 5.2(2.2 - 7.2) 6.5 (2.0 - 11.7) 1410 (430 - 2560)
09 09 07 1.9 1.9 1.5 5.2(2.2 - 7.2) 6.5 (2.0 - 11.7) 1410 (430 - 2560)
09 07 07 2.0 1.6 1.6 5.2(2.2 - 7.2) 6.5 (2.0 - 11.7) 1410 (430 - 2560)
07 07 07 1.7 1.7 1.7 5.2(2.2 - 7.0) 6.5 (2.0 - 11.3) 1410 (430 - 2460)
2-Room
12 09 OFF 2.9 2.1 OFF 5.0(1.9 - 6.5) 6.4 (1.6 - 11.0) 1400 (350 - 2400)
12 07 OFF 3.2 1.8 OFF 5.0(1.9 - 6.4) 6.4 (1.6 - 10.9) 1400 (350 - 2380)
09 09 OFF 2.5 2.5 OFF 4.9 (1.9 - 6.2) 6.3 (1.6 - 10.1) 1380 (350 - 2200)
09 07 OFF 2.5 2.0 OFF 4.5 (1.9 - 5.7) 5.5 (1.6 - 8.6) 1190 (350 - 1870)
07 07 OFF 2.0 2.0 OFF 4.0 (1.9 - 5.2) 4.6 (1.6 - 7.1) 1000(350 - 1550)
1-Room
12 OFF OFF 3.4 OFF OFF 3.4 (1.4 - 4.0) 4.4 (1.5 - 6.2) 950 (320 - 1350)
09 OFF OFF 2.6 OFF OFF 2.6 (1.4 - 3.3) 3.1(1.5 - 4.3) 680 (320 - 950)
07 OFF OFF 2.0 OFF OFF 2.0 (1.4 - 2.7) 2.4 (1.5 - 3.2) 520 (320 - 710)
Operating
Status
Combination of Indoor
Units
Heating Capacity (kW) Running Current (A) Power Consumption (W)
A B C A B C RATING (Min. - Max.) RATING (Min. - Max.) RATING (Min. - Max.)
3-Room
09 09 09 2.3 2.3 2.3 6.8 (2.2 - 8.4) 7.6(1.9 - 11.4) 1660(420 - 2480)
12 09 07 2.9 2.2 1.7 6.8 (2.2 - 8.4) 7.6(1.9 - 11.4) 1660(420 - 2480)
12 07 07 3.1 1.8 1.8 6.8 (2.2 - 8.4) 7.6(1.9 - 11.4) 1660(420 - 2480)
09 09 07 2.4 2.4 1.9 6.8 (2.2 - 8.4) 7.6(1.9 - 11.4) 1660(420 - 2480)
09 07 07 2.7 2.1 2.1 6.8 (2.2 - 8.4) 7.6(1.9 - 11.4) 1660(420 - 2480)
07 07 07 2.3 2.3 2.3 6.8 (2.2 - 8.4) 7.6(1.9 - 11.4) 1660(420 - 2480)
2-Room
12 09 OFF 3.8 2.9 OFF 6.7(1.6 - 8.0) 9.0 (1.7 - 12.2) 1970 (380 - 2670)
12 07 OFF 4.2 2.4 OFF 6.6(1.6 - 8.0) 9.0 (1.7 - 12.2) 1970 (380 - 2670)
09 09 OFF 3.1 3.1 OFF 6.2(1.6 - 8.0) 8.2 (1.7 - 12.2) 1800 (380 - 2670)
09 07 OFF 3.2 2.5 OFF 5.6(1.6 - 7.3) 7.1 (1.7 - 10.6) 1550 (380 - 2310)
07 07 OFF 2.5 2.5 OFF 5.0(1.6 - 6.4) 6.0 (1.7 - 8.7) 1320 (380 - 1910)
1-Room
12 OFF OFF 4.0 OFF OFF 4.0 (1.1 - 5.2) 6.4(1.5 - 9.8) 1400 (330 - 2150)
09 OFF OFF 3.0 OFF OFF 3.0 (1.1 - 4.2) 4.4 (1.5 - 7.2) 970 (330 - 1570)
07 OFF OFF 2.4 OFF OFF 2.4 (1.1 - 3.3) 3.3 (1.5 - 5.2) 720 (330 - 1130)
Compressor DA130A1F-28F Hermetically sealed DC twin rotary
Outdoor fan motor MLB051
Fuse 1, 101 — QFS-GA065JBZZ(20A,250V)
Fuse 6 — QFS-GA064JBZZ(1A,250V)
Fuse 3, 4 — QFS-GA062JBZZ(3.15A,250V)
Fuse 5 — QFS-GA063JBZZ(2A,250V)

AEX3M18JR
1 – 4
[5] WIRING DIAGRAMS
IPM P.W.B.
from ELECTROLYTIC CAPACITOR C10(+)
from ELECTROLYTIC
CAPACITOR C10(-)
from COMPRESSOR TERMINAL
W "ORANGE"
from COMPRESSOR TERMINAL
V "WHITE"
from COMPRESSOR TERMINAL
U "RED"
from CONTROL PWB CN14
from CONTROL PWB BCN1

AEX3M18JR
1 – 5
RELAY P.W.B and POWER SUPPLY P.W.B.
from 4 WAY VALVE from DIODE BRIDGE DB1 "~"
from CONTROL P.W.B. "CN9A"
from IPM "U", "V", "W" from IPM P.W.B. "CN114"
from POWER SUPPLY P.W.B.
from TERMINAL BOARD POWER SUPPLY "N"
from TERMINAL BOARD POWER SUPPLY "L"
from DC FAN MOTOR
from CONTROL BOX
from CONTROL P.W.B. "BCN15"
from ACTIVE FILTER MODULE
from TERMINAL BOARD UNIT C "1"
from TERMINAL BOARD UNIT C "N"
from CONTROL P.W.B. "BCN17"
from CONTROL P.W.B. "BCN16"
RELAY P.W.B. POWER SUPPLY P.W.B.

AEX3M18JR
1 – 6
CONTROL P.W.B and DISPLAY P.W.B
from THERMISTOR
from HEAT SINK THERMISTOR
from SUCTION THERMISTOR
from IPM PWB "CN101"
from RELAY P.W.B. "CN9"
from POWER SUPPLY P.W.B. "CN16"
from POWER SUPPLY P.W.B. "CN15" from POWER SUPPLY
P.W.B. "CN17"
from EXPANSION VALVE C
from EXPANSION VALVE B
from EXPANSION VALVE A
from TERMINAL BOARD POWER SUPPLY
from TERMINAL BOARD UNIT A - "N" UNITA~C-"2"
COMP. TENP. HEAT EXCHANGER TEMP. OUT DOOR TEMP. SUCTION TEMP.
DISPLAY P.W.B
CONTROL P.W.B

AEX3M18JR
1 – 7
(POWER SUPPLY PWB)
(IPM PWB)
(IPM PWB)
(DISPLAY PWB)
(RELAY PWB)
(CONTROL PWB)
C11, C13:
FC1
ORANGE
WHITE
RED
NR2
NR3
R49
100
1/4W
100
1/4W R47
100
1/4W R48
R113
C10
420V
C9
420V
1500uF TP
TN
P
N
R105
R106
10
11
8
9
6
7
12
13
14
3
0.1uF 50V 330pF
C38, C39, C40:
10k
R239
10k
1.0kF
5.6k
IC9 R204
R205
R202
R203
R200
R201
C93
0.1uF
PC1
PC81716
C34
C33
C32
C31
C30
C29
C28
C27
C26
C24
C23
C22
C21
C7
+
+
GREEN/YELLOW
GREEN
T1
250V
20A
T4
C3
275V
1uF
L6
1/4W
L
Thermal Fuse
(TERMINAL BOARD 1)
SACT32420
BLUE
C45
0.1uF
BLUE
BROWN
2
3
4
18
1
YELLOW YELLOW
BLUE
FC5
BLUE
Z
DB1
CT1
C8 C20
FC4
C12
C11 C17
C18
SA1
NR1
CN13
L2L1
L1
25 24
23
26
22
W
V
U
QM101(IPM)
17
16
1.8kF
R104
R103
e
FUSE101 630V
0.33uF
C121
TU
TV
TW
C
1/2W 180kF
R58, R60, R62:
1/2W 196kF
R57, R59, R61:
R56
R55, 56:
R55
1/2W 196kF
IC5
-
-
+
-
+
+
KIA339P
1/4W
100
R50
R58R57
R60R59
C37 C38 C40
C39 R52
7.5kF
R51
14.7kF
R53 R54
R62
R61
R52, R53, R54:
10V
C19
250V
ORANGE
BLUE
BLACK
GRAY
MRY1
PTC1
250V
3.15A
FUSE4
T5
+
-
T6
FUSE1
250V
4700pF
C12, C14:
BROWN
AC1
AC2
+
lo
P
-
+
ACT(PFC)
AF1
4
3
2
1
6
8IC4
STR-L472
-
+
9
8
7
6
5
4 3
2
11
2
3 4
5
6
7
8
9
10
Z
ZZ
YY
XX
WW
VV
UU
10
9
8
7
6
5
4 3
2
11
2
3 4
5
6
7
8
9
e
N
U
Z
Y
X
W
V
250V
10000pF
T2
2
133
1
2
L4
L3
C13
C14
1uF
275V
C1
C15
C16
275V
1uF
C2 R2
1/4W
R1
1/4W
510k
510k
2.2uF
275V
C8, 20:
L5
FB3
(TERMINAL BOARD A)
BLUE
BROWN
N
1
2
2
1
N
BROWN
(TERMINAL BOARD C)
(TERMINAL BOARD B)
BLUE
GREEN/YELLOW
N
1
2
GREEN/YELLOW
GREEN/YELLOW
R262
10k
R42
1k
1k
1k
R41
R43
R44
1.8k R46
R45
1.8k
1.8k
C53
10k
CN16
R10
1.0kF
R11
D1
R12
6.49kF
710 9
BCN16
BCN1
CN11
YELLOW
FC6
FC2
FC3
BROWN
BLUE
238:390
3.9k
FC8
FC9
FC10 FC11
1k
25V
25V
0.1uF
100kF
20kF
2.0kF
200kF
200kF
25V
25V
RY1
100
R8A
1W
CN4
275V
0.033uF
C4A
4-WAY
Valve
1
3
1
3
CN1
Motor
DC Fan
5
4
3
2
1
8
CN3
FUSE3
3.15A
250V
20A
220uF
A
BROWN
BLUE
B
CN2
CN101
CN114
CN14
WHITE
WHITE
FB2
FC7
ORANGE
BLUE
BLACK
RED
0.1uF
25V
C25
BT1
BT2
1/2W
150k 150k
1/2W
150k
1/2W 1/2W
150k
1000uF
44
16V
10u
C54
5V
R222
R223
R224
:10k
R222-224
5
61
2
3
4
R240 10k
IPM
4.64kF
1/4W
9.53kF
1/4W
1/4W
IC8
0.01uF
50V
C66 0.01uF
C67
50V
SW
PUMP DOWN
WINTER COOL
C80
1/4W 130k
130k 1/4W
1/4W
R233-
R238
R237 R236
R235
R234
R233
R232
R230
R229
R228
R219
R217
R216 R215
R214 R213
R212
R211
R210 R209
560F
R13F
R13E
R13D
R13C
R13B
R13A
D4 D5
D3
D2
0.01uF
50V
CN5
6.8kF TH5
(HEATSINK)
CN8B
3
10k
10k
D17
D8
D7
5V
D6
Q1
C97
C96
C59
C58
C57
C56
C55B
C55A
C55C
C55D
C55E
C55F
C55G
R28
a
bc
T
P
1
h
g
1
2
1
2
3
4
5 6
7
7
6
5
4 3
2 1
h g
10k
(Thermal Fuse)
0.01u
50V
C85
(POWER SUPPLY)
R3
3
2
4
1
5V
R9
KRC102S
1000pF
50V
5V
5V
C49
(U)
(V) (W)
(Z) (W)
(Y) (V) (X)
(U)
(O)
(Y)
(W)
(B)
VSS
VCC
P00
P01
P02
P03
P04
P05
P06
P07
P10
P11
P12
P13
P14
P15
P16
P17
P20
P21
P22
VCC
P23
C
P87 P86 P85 P84 P83 P82 P81 P80 P77 P76 P75 P74 P73 P72 P71 P70
X1
X0
VSS
P41
P42
RST
P43
P44
P45
P46
P47
P50
P51
P60
P61
P62
P63
P64
P65
P66
P67
AVCC
AVSS
AVR
MD0 MD1 MD2 P40 P37 P36 P35 P34 P33 P32 P31 P30 P27 P26 P25 P24
65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80
40 39 38 37 36 35 34 33 32 31 30 29 28 27 26 25
24 23 222 21 20 19 18 17 16 15 14 13 12 11 10 9 8 7 6 5 4 3 2 1
5141 42 43 44 45 46 47 48 49 50 52 53 54 55 56 57 58 59 60 61 62 63 64
IC1
JPF
0.1uF
5V
JP4
JP5
50V
1000pF
1000pF
50V
1000pF
50V
50V1000pF
2.2k
2.2k
2.2k
10k
5V
C68
0.01u
16V
UNIT C UNIT B
UNIT A LED1
SW1
SW
WIRE CHECK 10k
10k
10k
10k 10k
JP2
SW2
LED2
LED3
C43
100u
10V
C44
0.1u
5V
R30
1000pF
50V C119
R102
ZD101
130k 1/4W
1/4W 130k
1
2
3
4
R101
0.022uF
C120
50V
R100
S
R
421 6
18V
100uF
123456
123456
0.1uF
5V
7805
1
3
+
-
5 6
8
10
11
9
+
-
-
+
+
-
13
12
+
-
-
+
R17
10
2W
3300pF
0.01uF
15V
25V
2SA
1586G
250V
TR1
0.1uF
35V
150uF
35V
150uF
0.033uF
KIA7805API
0.1uF
10V
25V
680uF
680uF
18V IC7
D15
D13
D14
R18
R22
R23
R26
R27
220pF
R29
D9
10uF
50V
25V
R25
1/4W
R24
1/4W
R21
1/4W
Q2
1/4W
1/4W
2kV
1.5k
1.5k
10k
68k
22k
1.65kF
10k
10k
FB1
680
R14
1/4W 3.3k
R20
D10
ZD1
D12 R19
2k
1/4W
D11
1/4W
R35
R36
-
+
12
32
5
4
18V
IC5
1M
D16 R40
R38
0.1uF
50V
0.01uF
R34 0.1uF
Q4
R31
R32, R33:1/2W270kF
34.8kF
10k
1k
KIA339F
1.8k
5V
R37
1
2
3
4
15V
5
1
VP
VUFS VUFB
VPI
UPUP
VPI
VUFB VUFS
VP
1
5
4
3
22
3
4
19
20
UN
VNVN
UN
20
19
9
WPWP
9
FO
1818
FO
+
--
+
1000pF
C113
1000pF
C114
C115
1000pF
C116
1000pF
C117
1000pF
0.1uF
25V
C105
100uF C122
0.1uF
C123
-
++
-
VPC
14
15
1111
15
14
VPC
VNC
VNIVNI
VNC
C112
0.1uF
C104C104
330uF330uF
25V
R109
D100
10
13
1212
13
10
VWFB
VPIVPI
VWFB VWFSVWFS
8
7
66
7
8
VVFB
VPIVPI
VVFB
VVFS
R108-R111:
33
1/4W
R108
C101
100uF
25V
+
--
+
+
--
+
+
--
+
C106
D101
D102
D103
25V
100uF
C102
C107
C108
C109
0.1uF
0.1uF
0.1uF
0.1uF
0.1uF
C110
C111
R110
R111
C103C103
100uF
25V
0.1uF
HZ24-2
ZD100
WNWN
2121
C118
1000pF
R107 R112
6.8k 6.8k
S
C55A-55G:10u16V
Q8 Q6
c b a
4.64kF
13V
(UNIT A) (UNIT C)
(UNIT B)
3.3
R15 R16
3.3
1/2W
1/2W
470pF
B
O
Y
W
1/4W
R257
1/4W
R255
2.2k
1/4W
R253
1k
1k
1k
R256
R254
R252
2.2k
2.2k
Q15
Q14
1/4W
1/4W
1/4W
IC3
KID65004AP
10k
R260
10k
R261
D29
GR
R
O
Y
W
D26
D27
D28
GR
R
BL
O
Y W
BL
R
BL
O
W
Y
GR
3
4
5
6
1
2
3
4
5
6
2
1
6
5
4
3 2 1
D30
D31 D32 D33
D34
D35
D36
D37
C48
C50
O
Y
W
B
5V
KRC105S
Q3
R226 1k
0.01uF
50V
50V
0.01uF
C78
50V
0.01u
C79
0.1u
10k
R227
R231
5V
R225
10k
1
2
3
4
5
6
7 8
TH4
(heat exchange)
(compressor)
(thermistor)
R98A-98G:6.8kF
R98G
R98F
R98E
R98D
R98C
R98B
R98A
R97E
R97D
R97C
R97B R97A
R97F
R97G
C86C
C86B
C86D
C86E
C86G
C86H
C86F
R97H
C86A-C86H:0.01u50V
5V
6 5
4
3
2
1
TH8
(SUCTION C)
TH7
(SUCTION B)
TH6
(SUCTION A) 0.1uF
C60
100uF
C61
10V
R97A-R97H:10k
C86A
1.8k
R88
C72
C73
0.1u
0.1u
C69
4700P
0.1u
C82
4700P
C70
4700P
250V
250V
PC817X3
PC817X3
PC817X3
3.3K
1000P
C76
50V
1000P
C75
50V
C83
1000P
50V
C81
250V
PC9
PC8
PC7
PC6
PC4
PC5
PC853X
PC853X
PC853X
D19
D20 D21
R76
R77
4.7k
56k
R79
3.3k
2W
1k
1k
2W
1k
2W
R80A R80B R80C
14
2
4
3
1
R81
4.7k
56k
R82
R84
3.3k
2W
1k
2W
1k 1k
2W
R85A R85B R85C
32
14
23
41
R86
4.7k
R87
56k
R89
1k
2W 2W
1k
1k
2W
R90A R90B R90C
32
14
2
41
3
32
1.8k
1.8k
R78
R83
5V
7 3
1
CN6
N A
B
C
5
Q
R
R221 270
0.1u
C47
50V
1u
f
OSC1
C98
0.1u R220
270
C46
IC2
1
2
3
4
5
6
7
8
9
P
Q T S
R
flash writer
monitor
(CN) 1
2
3
4
10k
R66
5V
1k
R68
1k
R67
R69
4.7k
5V
4.7k
R70
IC6
EEPROM
8 7
5
6
1
2
3
44
3
2 1
5V
+
-
3
2
11
2
3
C63
50V
C62
0.1u
10k
R95 10k
R93
5V
Q11
13V
MRY1
10k
R259
Q13 Q13-15:2SA1020Y
D38
R92
(suction)
(outdoor)
TH1
TH2
TH3
CN8A
CN8C
10k
R65
1/4W
5V
3.3k 3.3k
R94
R96
BCN13
CND
CNE
CNF
BCN11
0.01u
4.7k
1/4W
R73
10k
KRC245M
CN15
BCN15
654321
5V
15V
654321
KRC105S
KRC105S
Q7
KRC105S
BCN17
4
5
6
4
5
6
7
8
7
8
1
2
3
1
2
3
13V
5V 15V
CN17
KRA102S
(valve A)
CN12A
(valve B)
CN12B
(valve C)
CN12C
18kF
25V
25V
25V
25V
25V
25V
25V
25V 25V
25V
25V
25V
25V
25V
25V
6.8k
Q9
KRC105S
Q10
R91 10k
47uF
10V
C64
KRA102S
15V
C65
RY1
CN9
3
2 4 5 1
5 4
1
2
3
13V
CN9A
FUSE6
250V
1A
FUSE5
2A 250V
1M
1/2W
R13A, 13B, 13C, 13D, 13E, 13F:
KID65004AP
IC12
R100:5W 0.020
R32
R33
C41
C52
C51
50V
0.01uF
15V
680pF
R6
C6
R7
R4
R5

AEX3M18JR
2 – 1
AEX3M18JR ServiceManual

CHAPTER 2. EXPLANATION OF CIRCUIT AND OPERATION
[1] BLOCK DIAGARM
CPU
Pump down switch circuit
Unit A thermo. circuit
Unit B thermo. circuit
Thermistor unit A
Thermistor unit B
Compressor
CN8A
CN8A
CN8A
Suction thermistor CN8C
CN5
Expansion valve A drive circuit
Expansion valve B drive circuit
4-way valve relay drive circuit 4-way valve
Wire check switch circuit
Position detection circuit
Thermal fuse in terminal board
Thermal fuse circuit
LED drive circuit
Heat exchanger pipe thermo. circuit
Compressor thermo. circuit
CPU reset circuit
Serial I/O circuit
Power transistor module drive circuit
Outdoor fan motor drive circuit
Power supply circuit
Expansion valve A
Expansion valve B
Expansion valve C
CPU oscillator circuit
AC overcurrent detection
DC overcurrent detection circuit
LED
Heat exchanger pipe thermistor
Compressor thermistor
Current transformer
Compressor
Power transistor module
Outdoor fan motor
Smoothing circuit Active filter circuit Filter circuit AC power
Unit - unit wiring
(AC power and serial
signals)
20 A
Fuse
1A
Fuse
Outdoor temp. thermo. circuit Outdoor temperature thermistor
20 A
Fuse
2A
Fuse
3.15 A
Fuse
Expansion valve C drive circuit
DC power supply circuit
(RE)
(OR)
(G)
(BL)
(WH)
Unit C thermo. circuit Thermistor unit C (BR)
Suction pipe thermistor CN8A
Suction pipe thermo. circuit (BK)
DC over voltage detection circuit
Heat sink thermistor CN8B
Heat sink thermo. circuit (BK)

AEX3M18JR
2 – 2
[2] FUNCTIONS
1. FREQUENCY CONTROL
1) AC current peak control
2) Prevention control of outdoor heat exchanger overheating
If the temperature of the outdoor heat exchanger exceeds the over-
heating prevention line 1 or 2 during cooling, the operating fre-
quency is lowered by approximately 5 to 15Hz. After that, the
frequency is lowered approximately 5Hz once every 60 seconds or
approximately 15Hz once every 120 seconds. When the tempera-
ture of the outdoor heat exchanger goes below the overheating
prevention clear line, the frequency is raised by approximately 5Hz
once every 60 seconds, and normal operation is restored. If the fre-
quency is lowered to minimum frequency without the temperature
of the outdoor heat exchanger decreasing and this condition lasts
for 1 minute, the compressor will be stopped.
3) Prevention control of compressor overheating
If the temperature of the compressor exceeds approximately 108
°C, the operating frequency is lowered approximately 5Hz. After
that, the frequency is lowered approximately 5Hz once every 60
seconds. When the compressor temperature drops below approxi-
mately 108°C, the frequency is raised approximately 5Hz once
every 60 seconds, and normal operation is restored. If the fre-
quency is lowered to minimum frequency without the temperature
of the compressor decreasing, and this condition lasts for 1 minute,
the compressor will be stopped.
4) Prevention control of indoor heat exchanger overheating
Two minutes after room several decrease If the temperature of any
of indoor heat exchangers exceeds the overheating prevention line
1 or 2 during heating, the operating frequency is lowered to mini-
mum frequency. When the temperature of all of indoor heat
exchangers go below the overheating prevention line 1, the fre-
quency is raised by approximately 5Hz once every 60 seconds,
and normal operation is restored. If the condition that the frequency
is minimum lasts for 2 minutes, the compressor will be stopped.
<when normal >
If the temperature of any of indoor heat exchangers exceeds the over-
heating prevention line 1 or 2 during heating, the operating frequency
is lowered by approximately 5 to 15Hz. After that, the frequency is low-
ered approximately 5Hz once every 60 seconds or approximately
15Hz once every 90 seconds. When the temperature of all of indoor
heat exchangers go below the overheating prevention line 1, the fre-
quency is raised by approximately 5Hz once every 60 seconds, and
normal operation is restored. If the condition that the frequency is min-
imum lasts for 2 minutes, the compressor will be stopped.
2. OVER CURRENT PROTECTION
DC over current detection, AC over current detection. To protect
against over current due to sudden change in load, the compressor is
stopped if 24A DC is exceeded in the DC section. If the set value of
AC current is exceeded in the AC section, the compressor is stopped.
90 seconds after the compressor has been stopped, another starting
try will be made. Three retries are allowed. On the fourth retry, a com-
plete stop request signal is sent to the indoor unit, and the outdoor unit
will remain stopped until the indoor operation is stopped. DC over cur-
rent is detected by the power module. AC over current is detected by
CT1, on the outdoor PWB.
3. COMPRESSOR PROTECTION CONTROL
If the temperature of the compressor exceeds 113°C, the compressor
is stopped. In this case, the outdoor fan is not stopped until the tem-
perature of compressor drops below 99°C. In 90 seconds after the
compressor is stopped, if the temperature is below 90°C, another
starting try will be made. Three retries are allowed. On the fourth retry,
a complete stop request signal is sent to the indoor unit, and the out-
door unit will remain stopped until the indoor operation is stopped.
4. POWER TRANSISTOR MODULE PROTECTION
If the temperature of the heat-sink exceeds 90°C, the compressor is
stopped. In this case, the outdoor fan does not stop, and when the
temperature of the heat-sink decreases to 80°C 180 seconds after
operation is stopped, another try will be made. Three retries are
allowed. On the fourth retry, a complete stop request signal is sent to
the indoor unit, and the outdoor unit will remain stopped until reset is
performed. At this time, the 3-minutes delay for control of the outdoor
unit will not function; therefore, do not cancel by removing the plug and
cutting the power. Also if the temperature of the heat-sink exceeds
100°C, a complete stop request signal is sent to the indoor unit, and
the outdoor unit will remain stopped until reset is performed. At this
time, the 3-minutes delay for control of the outdoor unit will not func-
tion; therefore, do not cancel by removing the plug and cutting the
power.
5. SERIAL SIGNALS
Serial signals consist of all 96-bit signals. If the condition as outdoor
unit unable to receive a serial signal from the indoor unit continues for
30 seconds, it closes the expansion valve which corresponds to the
room which can not be communicated. If all indoor units can not com-
municate with the outdoor unit, the compressor is stopped.
6. THERMISTOR OPEN OR SHORT
When compressor, heat exchanger, outdoor thermistor, suction ther-
mistor (CN8A) are in OPEN or SHORT condition, even if they are in
the condition which an operation signal is transmitted from indoors, the
compressor will not start. If any suction thermistors (CN8C) become
OPEN or SHORT resistance, the protective procedure will work only
for the cycle corresponding to the malfunctioning suction thermistor.
7. MISWIRING CHECK
“Mis-wiring check” is conducted by detecting the indoor heat
exchanger temp. For example, when the expansion valve for only
room A is open, and the wiring is correct, the indoor heat exchanger
temp for room A will reduce. If the wiring is incorrect, the indoor heat
exchanger temp for a different room will reduce.
8. SAFETY TIME
When the unit is operated by the remote control after the breaker is
turned on, the safety device of the compressor will work and the com-
pressor will not operate for 90 seconds.
Cooling mode Heating mode
13.6A 13.6A
Overheating Prevention line 1 55°C Lower 5Hz once every
60 seconds
Overheating Prevention line 2 57°C Lower 15Hz once
every 120 seconds
Overheating Prevention clear line 54°C
When ON
(When OFF)
Overheating
prevention
line 1
900
44ºC
(57ºC)
54ºC
(59ºC)
48ºC
(54ºC)
51ºC
(57ºC)
57ºC
(62ºC)
47ºC
(60ºC)
2100 5200 7200
Overheating
prevention line 2
Cooling mode Heating mode
16.0A 16.0A

AEX3M18JR
2 – 3
9. PUMP DOWN SWITCH
When the PUMP DOWN SWITCH (SW1) is pressed for 5 seconds or
more, the total A/C system will start its TEST RUN automatically and
the compressor frequency will be 48.3 Hz. When operating only the
outdoor unit (cooling 48.3 Hz fixed mode) To make only the outdoor
unit run in cooling mode, and apply a voltage of 230 V AC to N and L
on the terminal board and push the pump down switch. (SW1) (Avoid
operating the outdoor unit alone for long periods of time.)
10. CONTROL OF COMPRESSOR OR AND EXPAN-
SION VALVE
For 90 seconds after turning on the AC power, the compressor will not
be activated even if indoor units request the compressor to do so. If
the compressor receives a request from one or more indoor units after
90 seconds have passed, it will be turned on and the expansion valve
corresponding to the requesting indoor unit will be opened. When the
indoor unit of a room requests for the cooling operation to the outdoor
unit and it runs responding to the request, requests for the heating
can't be accepted if the indoor units in other rooms send individual
requests. If the indoor unit in another room sends a request for the
heating operation, the operation lamp and timer lamp of the indoor unit
in that room start flashing in turn to inform that the unit is in the standby
mode. If the operation in one room is stopped while the indoor unit in
another room is in the stand-by mode, the operation mode requested
by the indoor unit which is now in the stand-by mode will be accepted.
At this time, the compressor will be temporarily stopped to switch the
four- way valve and restart after 90 seconds. During the cooling or dry
operation, the expansion valve corresponding to the indoor unit that is
not running is closed. Therefore, the refrigerant will not flow into those
units However, if the heating operation is in progress, it is possible that
it flows into indoor units which are out of operation depending on the
cycle conditions. As a result, the indoor exchanger may be heated up
even if it is not activated. This is not abnormal. When the operations in
all rooms are stopped, the compressor is off and the expansion valves
in all rooms are fully opened.
11. DEFROST OPERATION
1) Overview
Defrosting begins during heating if the conditions for compressor
operation time and outdoor heat exchanger temperature are met.
When defrosting begins, the indoor and outdoor fans stop. Defrost-
ing stops when the temperature of the outdoor heat exchanger
goes above approximately 15°C or defrosting time exceeds 10 min-
utes.
2) Defrosting
If the compressor operation time is more than 20 minutes in the
heating mode and the outdoor air temperature and outdoor heat
exchange temperature satisfy the defrosting conditions, the
defrosting operation is started. When the defrosting operation is
started, the indoor fan starts to run intermittently. When the outdoor
heat exchanger temperature reaches approx. 15°C or above or
when the defrosting time exceeds 10minutes, the defrosting opera-
tion is quit.
3) During defrosting
When defrosting begins, the compressor stops. Approximately 1
minutes later, the compressor reactivates in the refrigeration cycle,
and the outdoor heat exchanger is defrosted. Each mode is as fol-
lows:
The outdoor fan is s topped
The operating frequency is as shown in the table below.
The indoor fan is s topped.
All expansion valve are open.
for 5 minutes 3900 rpm
after that 3700 rpm
4) Defrost stop
When defrosting time exceeds 10 minutes When the temperature
of the outdoor heat exchanger rises above approximately 15°C
Defrost stop is determined by either of the above conditions, and
the compressor is stopped. At the same time, the outdoor fan go
ON. The compressor is reactivated in the heating cycle 1 minutes
after it was stopped, and normal control resumes.
12. Power factor module Output voltage
If a voltage error over 450V is detected at power factor module output
voltage, the compressor is stopped for 3 minutes. In this case, the out-
door fan does not stop for 3 minutes, and another try will be made.
Three retries are allowed. On the fourth retry, a complete stop request
signal is sent to the indoor unit, and the outdoor unit will remain
stopped until reset is performed. At this time, the 3 minutes delay for
control of the outdoor unit will not function; therefore, do not cancel by
removing the plug and cutting the power.
.
Defrost
mask time
Defrost
mask time
Defrost
mask time
Heating
begins
Defrosting
Max. 10 min.
Defrosting
Max. 10 min.
More than
20 min.
More than
20 min.
Defrosting
Max. 10 min.
Heating
operation
start Defrosting
Max. 10 min.
More than
20 min.

AEX3M18JR
2 – 4
[3] ACTIVE FILTER CIRCUIT
This circuit uses Active Filter Module and IPM as the figure below for the high efficiency operation of compressor.
1. Active Filter
In the case the direct current is obtained by the diode bridge and smooth capacitor from the commercial power source, the current wave shape will be
the pulse shape at the peak of the voltage wave shape as shown in the figure below. For this reason, the harmonic current will be generated and at
the same time the power factor will be deteriorated. While monitoring the AC input voltage in the control circuit, in order to be the same phase and
wave shape as this voltage wave shape, IGBT is made ON/OFF by the carrier frequency of approximately 20 kHz. By adoption of this Active Filter,
the current wave shape can be made to the sine wave synchronized to the commercial power source and the power factor can be made to almost
99%. As a result of this, reactor can be disused. Active Filter works for the improvement of power factor and as the countermeasures for the harmonic
current.
2. Active Filter Voltage Raise Circuit
The IGBT in the figure below is the switching transistor of the Active Filter. By adding ON signal to the gate of IGBT from the control IC, IGBT turns
ON and the collector current Ic flows. This current flows from the + side of the diode bridge DB to the Choke coil, the - side of the diode bridge DB
through IGBT from the Choke coil L. At this time, energy is stored in the choke coil L. Next, when gate signal of IGBT turned OFF, IGBT will be turned
OFF and the energy stored in L during the ON time of IGBT will be discharged through the diode D, electrolytic capacitor C, load, primary side and the
+ side of DB. Assuming the input voltage of Active Filter (voltage between + and - of DB) as Ei, the output voltage (voltage at the both ends of smooth
capacitor) as Vo, switching cycle of IGBT as T and ON time of IGBT as ton, the voltage between collector emitter of IGBT Vs will be as follows;
Vs= 0 (during ON of IGBT: ton)
Vs= Vo (during OFF of IGBT: T-ton)
Here, assuming no loss in L and IGBT, average value of Vs turns equal to Ei,
Ei = (T-ton)/T x Vo
Therefore
Vo = T/(T-ton) x Ei
As ton is a smaller value than T, output voltage Vo will be higher than input voltage Ei.
Sine wave current
Noise filter
circuit
AC
Choke coil
+Compressor
Rectification
circuit
Control source
IPM
Control
source
ON/OFF
Voltage raise signal
Compressor
Driving signal
IPM
Active Filter
IC1
Positional
detection
Power-supply voltage
(50Hz)
Current waveform
(Before)
Current waveform
(Active Filter)

AEX3M18JR
2 – 5
3. Active Filter Driving Electronics Circuit
At the operation of compressor, the microcomputer (IC1), as the 50th pin gets “H”, will turn the transistor Q4 ON through the transistor Q3. By this,
18V is supplied to the 3rd pin of connector BCN13 of the Active Filter and the Active Filter will be turned ON.
4. Protection Circuit of Active Filter
In order to prevent from the destruction of Active Filter due to the excessive over output voltage of Active Filter, the Active Filter will be turned OFF
immediately at the abnormal output voltage by monitoring the output voltage. At the same time, the operation of compressor will be stopped. Detec-
tion circuit of the abnormal voltage detects the abnormal voltage by inputting the output voltage of Active Filter to the 4th pin of comparator IC (IC5) at
the divided voltage by the resistors (R31, R32 and R33) and comparing with reference voltage. When the output voltage of Active Filter reaches 450V
or higher, the 4th pin of IC5 will be higher than the reference voltage at the 5th pin, the output of comparator will be reversed (H→L), the L signal will
be entered at the 52nd. pin of microcomputer (IC1) and the operation of the Active Filter will be stopped.
Active Filter Circuit
+
DB
D
L
IGBT
RL
IC
Ei Vs Vo
C
Control
+
-
L1 L2
P
Io
BCN13
12 34 5 6
PFC control
(+)
(-)
Active Filter Circuit
+
DB
D
L
IGBT
RL
IC
Ei Vs Vo
C
Control
+
-
L1 L2
P
Io
BCN13
12 34 5 6
PFC control
(+)
(-)
23
12
0V
0V 0V
0V
18V
R36
1M
R35
34.8KF
R34
9.53KF
R31
4.64KF
C57
0.1u
50V
4
5
-
+
C56
0.1u
50V
IC1
52
R32
270KF
R33
270KF
DC
Voltage
IC5
5V

AEX3M18JR
2 – 6
[4] EXPLANATION OF IPM DRIVE CIRCUIT
The power supply for the IPM drive, and the shunt resistor for over current detection, etc., are provided out of the IPM (in control PWB).
1. IPM drive power supply circuit
The power supply for driving the upper-phase IGBT (HU, HV, HW) drive employs a Bootstrap system.
The 15-V power supply for the lower-phase IC is provided by the control printed circuit board (PWB).
1. Brief explanation of Bootstrap system (single power drive system)
To supply power to the upper-phase IC, the microcomputer (IC1) turns ON the lower-phase IGBT (LU, LV, LW).
It results in a charging current that flows through the electrolytic capacitor in each upper-phase IC input and charges the Bootstrap capacitor up to
15V voltage.
The power supply for the subsequent stages is stored when the lower-phase IGBT is ON in common drive control of the compressor.
2. DC over current detection circuit
When a current about 24A or higher flows through the shunt resistor (R100) on IPM printed circuit board (PWB), the voltage on this resistor is input to
IPM CIN pin (16). Then, the gate voltage of the lower-phase IGBT (LU, LV, LW) inside the IPM turns OFF to cut the over current off. At the same time,
an L output which lasts about 1.8 ms is generated from IPM Fo pin (18), and it results in an L level input to over current detection input pin (53) of the
microcomputer (IC1) and then turns OFF the compressor driving signal output (IC1 from pins (65) to (70)) to the IGBT gate.
P(Vcc)
U,V,W,
V
D
V DB
V CIN ( n )
N-side
IGBT
N(GND)
Bootstrap capacitor
High-voltage-withstanding,
high-speed recovery diode
LVIC
(LU,LV,LW)
HVIC
(HU,HV,HW)
Bootstrap circuit
Initial charge period
Charging current group
SET
RESET
About 24A
SC
SC reference voltage
Delay by CR time constant circuit
About 1.8 ms
a1
Protection circuit status
Output current Ic (A)
Sense voltage relative
to shunt resistance
Error output Fo
(Lower phase)
Internal IGBT gate

AEX3M18JR
2 – 7
3. 120°energizing control (digital position detection control)
This control system detects the digital position detection signal and adjusts the rate of acceleration/deceleration accordingly. The motor's induced
voltage waveform is input to the comparator in the form of PWM-switched pulse, and a position detection signal is generated as a reference voltage
which is equal to 1/2 of 370 VDC. However, since there is no induced voltage waveform when the PWM waveform is OFF, the microcomputer works
in an internal processing so that detection is enabled only when it is ON. Based on the position signal detected, actual PWM waveform output timing
is determined. Since it does not use a filter circuit, the accuracy of detection. The microcomputer works in an internal processing to eliminate spiky
voltage during the regenerative process. Furthermore, even if the induced voltage is low, position detection is still possible, and it allows sensor-less
operation at low rotation speed in the initial stage of operation. These reduce the starting current and improve reliability of IPM.
4. 180°energizing control
This is the control system to moderate the speed by the
current phase difference for higher efficiency and lower
noise of the compressor. The current phase difference
control is the control system paid attention to the interre-
lation between efficiency and phase gap generated by
the applied voltage of motor and current in the coil of
motor as shown in the figure below.
This control is the forced magnetization system indepen-
dent of the location of rotor, detecting the phase differ-
ence between driving voltage phase and line current
phase flowing in motor coil, and controls the modulation
rate data to get the phase difference at the best effi-
ciency.
5. DC Current Detection Sensor Circuit
Control of current phase difference is made by reading in the phase difference generated at the both edges of shunt registor (R100) by the compres-
sor electrifying current on the PWB through the Op-amp (IC9) to the microcomputer. This is a control to modulate up to the phase with the best effi-
ciency by comparing the phase of this input current, so called compressor electrifying current, with the compressor driving voltage. In the case that
phase difference between motor voltage and current is large (current delay is large), the control will be made by lowering the compressor modulation
rate data (compressor effective value).
Comparator output waveform
(Position signal waveform)
Terminal voltage waveform
Reference voltage
(1/2 of DC voltage)
Spiky voltage
(cancelled)
Ჷ(
ᲢᲣ
Motor voltage
Voltage /Current
phase difference
Motor current
Concept chart of the current phase difference control
Best timing Difference of current
and voltage peak
Efficiency
FUSE 101
250V 20A
5V
5V
0V
0V
15V
N
CIN
P
TU
TV
TW
Y
ZY
Z
IPM
IC1
C121
D8
C96
1000P
C119
ZD101
R200
1K
R201
100KF
IC9
C97
0.1μ
1
-
+
R202
20KF
R113 18KF R203
2.0KF
R204
200KF
R205
200KF
3
2
4
8
S
RC
FC1
Inverter current detection circuit
630v
0.33Ǵ
1000p 0.02
R100

3 – 1
CHAPTER 3. FUNCTION AND OPERATION OF PROTECTIVE PROCEDURES
[1] PROTECTIVE FUNCTIONS AND OPERATIONS
NO. Function Operation
Description Detection time Restart condition Restart
time
In
door
Out
door
1 DC over current
Compressor is stopped if a current approxi-
mately 24A or more flows in the power tran-
sistor module.
During compres-
sor operation
Automatically restarts
after safety time (180
seconds)
4 times Yes Yes
2 AC over current
Lowers the operating frequency if the com-
pressor AC current exceeds set value
(16.0A). Stops the compressor if the current
exceeds at minimum frequency.
During compres-
sor operation
Automatically restarts
after safety time (180
seconds)
4 times Yes Yes
3
Compressor over-
heat prevention con-
trol
Lowers the operating frequency if the tem-
perature of the compressor thermistor (TH1)
rises above 108°C. Compressor is stopped if
the thermistor stay above 108°C for 2 min-
utes at minimum frequency.
During compres-
sor operation
Automatically restarts
after safety time (180
seconds)
No limit No No
4Compressor high
temperature error
Compressor is stopped if the compressor
thermistor is above 113°C (Or when TH1
shorts)
During compres-
sor operation
Automatically restarts
when thermistor (TH1)
temperature falls below
99°C (approximately 30
minutes)
4 times Yes Yes
5
Outdoor heat
exchanger overheat
prevention control
Lowers the operating frequency if the tem-
perature of the outdoor heat exchanger rises
above 57°C during cooling. Stops the com-
pressor if the temperature stays above 57°C
for 2 minutes at minimum frequency
During compres-
sor operation
Automatically restarts
after safety time (180
seconds)
No limit No No
6 Thermistor short
Compressor ia stopped, if heat exchanger or
outdoor thermistor shorts. Close the expan-
sion valve of the corresponding room, if
some suction thermistor shorts.
When the room
is activated turns
ON and the com-
pressor starts.
Operation OFF 1 time Yes Yes
7 Thermistor open
Compressor is stopped, if compressor or
heat exchanger or outdoor thermistor opens.
Close the expansion valve of the corre-
sponding room, if some suction thermistor
shorts. opens.
When the room
turns ON and the
compressor
starts.
Operation OFF 1 time Yes Yes
8AC abnormal cur-
rent
Compressor is stopped, if the operating fre-
quency is above 70Hz and the compressor
current is below 0.8A.
During compres-
sor operation
Automatically restarts
after safety time.(180
sec.)
4 times Yes Yes
9 Serial signal error
INDOOR
If open, while timer LED blinks, operation is
continued. If short, operation is continued.
OUTDOOR
Closes the expansion valve of the corre-
sponding room if the outdoor unit does not
receive a serial signal from one or more
indoor unit for 30 seconds.
Compressor is stopped, if the outdoor unit
does not receive a serial signal from all
indoor units.
During operation
Automatically restarts
as soon as the serial
communication
becomes possible.
No limit Yes Yes
10 Miswiring check
error
Compressor is stopped, and miswiring check
operation ends.
During miswiring
operation
Miswiring check opera-
tion will not restart
automatically.
4 times Yes Yes
11
Indoor heat
exchanger overheat
prevention control
Lowers the operating frequency if the tem-
perature of any of indoor heat exchanger
rises high temperature during heating.
Stops the compressor if the temperature stay
high for 2 minutes at minimum frequency.
During compres-
sor operation
Automatically restarts
after safety time.(180
sec.)
No limit No No
12
Power factor mod-
ule (Active Filter)
over voltage error
Compressor stops if DC voltage is 450V or
higher.
During compres-
sor operation
Automatically restarts
after safety time.(180
sec.)
4 times Yes Yes
13
Power factor mod-
ule (Active Filter)
low voltage error
Compressor stops if DC voltage is 280V or
lower.
During compres-
sor operation
Automatically re-starts
after safety time.(180
sec.)
4 times Yes Yes

3 – 2
✩1 The outdoor unit restarts four times before the indoor unit error is displayed (complete shutdown).
[2] TROUBLESHOOTING GUIDE
1. SELF-DIAGNOS IS FUNCTION AND DISPLAY MODE
1) To call out the content of the self-diagnosis memory, hold down the emergency operation button for more than five seconds when the indoor unit is
not operating.
a) According to the content of the self-diagnosis memory, the Operation LED (main category) and the Plasmacluster Ion LEDs (sub-category)
flash in sync with the Timer LED on the indoor unit.
b) In the event a complete shutdown occurs due to a malfunction, the Operation LED (red), Timer LED (yellow), Plasmacluster Ion LED (blue)
flash to indicate the general information of the generated malfunction.
c) If the power cord is unplugged from the AC outlet or the circuit breaker is turned off, the self-diagnose is memory loses the stored data.
2) Display of detailed self-diagnosis result with main category and sub-category indications When malfunction information is called out, the main cat-
egory and sub-category of the self-diagnose is result are indicated by the Operation, Timer, and Plasmacluster Ion LEDs on the indoor unit.
14
Power factor mod-
ule (Active Filter)
clock error
When power source frequency cannot be
determined (at startup) or when power
source clock can not be detected for 1 con-
tinuous second (at startup).
At compressor
start up, when in
operation.
Compressor continues
operation without stop-
ping.
None Yes Yes
15 Outdoor unit DC fan
error
Operation stops if there is no input of rotation
pulse signal from outdoor unit fan motor for
30 seconds.
When outdoor
unit fan is in
operation.
Operation OFF or ON. Yes ✩1Yes Yes
16 DC compressor
rotation error
Operation stops if rotation of compressor is
abnormal.
During compres-
sor operation
Automatically restarts
after safety time.(180
sec.)
8 times Yes Yes
17
IPM overheat pre-
vention control.
IPM high tempera-
ture error
The compressor stops if the temperature of
Heat sink exceeds 90°C.
During compres-
sor operation
Automatically restarts
after safety time.(180
sec.)
No limit No No
18 Thermal fuse error When thermal fuse in the outdoor terminal
board below. Operation OFF 1 times Yes Yes
NO. Function Operation
Description Detection time Restart condition Restart
time
In
door
Out
door
The self-diagnosis display function of the outdoor unit indicates the error information by flashing LED1 on the
outdoor unit according to the content of self-diagnosis.
The self-diagnosis display function of the outdoor unit is active only for about 3 to 10 minutes after self-diagnosis is
performed during operation, and the display returns to normal condition after this display period.
The content of self-diagnosis cannot be called out by the self-diagnosis display function of the outdoor unit.
*1: Example of self-diagnosis result displayed on indoor unit: Suction thermistor open-circuit error
Timer LED [yellow] ON
OFF
Basic flashing cycle due to error 1 sec 1 sec 1 sec 5 sec
Figures in ( ) indicate numbers (binary notation) assigned based on the flashing sequence.
Flashing for main category indication
Flashing for sub-category indication
ON
OFF
Operation LED [red]
Plasmacluster Ion LED [blue]
Malfunction No.
Main category Sub-category
Example of self-diagnosis display on outdoor unit : Compressor high-temperature abnormality
0.5 sec 0.5 sec 0.5 sec 0.5 sec 0.5 sec 0.5 sec 0.5 sec 0.5 sec 0.5 sec 0.5 sec0.5 sec 0.5 sec 0.5 sec
ON
OFF
*2:

3 – 3
0
-0
1
-0
5
-0
6
-0
7
-0
8
-0
11 -0
2
-0
-1
-2
-3
-1
-2
-3
-1
-2
-5
-4
-1
-2
-3
Status of
indoor/outdoor
units
Indication by
LED1 on
outdoor unit
*2
Indication on indoor unit
Contentofdiagnosis
Inspection location/methodRemedy
Floor/ceiling Wall
(Panel)
Lighting pattern at the time of timer lamp lighting
Main Sub
for5seconds MaincategorySub category
Indoor/outdoor units in
operation
Normal
flashing Normal__
_
_
_
Indoor/outdoor units
in complete shutdown
1t
imeOperation lamp(RED)
Clusterlamp(BLUE)
Operationlamp(RED)
Cluster lamp(BLUE)
Operation lamp(RED)
Cluster lamp(BLUE)
Operation lamp(RED)
Cluster lamp(BLUE)
Operationlamp(RED)
Cluster lamp(BLUE)
Operation lamp(RED)
Cluster lamp(BLUE)
Operation lamp(RED)
Cluster lamp(BLUE)
Operationlamp(RED)
Cluster lamp(BLUE)
Operation lamp(RED)
Cluster lamp(BLUE)
Operationlamp(RED)
Cluster lamp(BLUE)
Operationlamp(RED)
Clusterlamp(BLUE)
Operationl
amp(RED)
Cluster lamp(BLUE)
Operationl
amp(RED)
Cluster lamp(BLUE)
Operationl
amp(RED)
Cluster lamp(BLUE)
Operationl
amp(RED)
Cluster lamp(BLUE)
Operationl
amp(RED)
Cluster lamp(BLUE)
Operationl
amp(RED)
Cluster lamp(BLUE)
Operationlamp(RED)
Cluster lamp(BLUE)
Operationl
amp(RED)
Cluster lamp(BLUE)
Operationlamp(RED)
Cluster lamp(BLUE)
Operationl
amp(RED)
Cluster lamp(BLUE)
Outdoor unit
thermistor
short-circuit
(1)Measureresistance of the outdoor unit thermistors.
(TH2~4,6~8:Approx.4.4kat25ºC
(2)Checkt
he lead wire of the outdoor unit thermistor for torn sheath and
shortcircuit.
(3)No abnormality foundinabove inspections (1)and (2).
(1)Replacetheoutdoor unitthermistor assembly.
(2)Replace theoutdoor unit thermistor assembly.
(3)Replace the outdoor unit control PCB assembly.
Indoor/outdoor units in
complete shutdown
2time Cycle
temperature
(1)Check theoutdoor unit air outlet for blockage.
(2)Check ifthepowersupply voltage is AC2
30V atfullpower.
(3)Checkt
he pipeconnections for refrigerant leaks.
(4)Measureresistance of the outdoor unit compressor thermistor.
(TH1:Approx.53k at 25ºC)
(5)Check the expansion valve for proper operation.
(1)Ensure unobstructed airflowfromthe outdoor unit air outlet.
(2)Connect powersupply of proper voltage.
(3)Charge the specifiedamount of refrigerant.
(4)Replace the outdoor unitcompressor thermistorassembly.
(5)Replacethe expansion valve coil,expansion valve or outdoor unit
control PCB assembly.
Indoor unit in operation
Outdoor unit intemporary
stop
(Temporary stop for cycle protection)
(Temporary stop for cycleprotection)
(Temporary stopfor cycle protection)
IPM high temperature error (1)Measure resistance oftheheat-sink thermistor (CN8B). (1)Changetheheat-sink thermistor.
Indoor/outdoor units in
completeshutdown
5timeOutdoor unit
thermistoropen-
circuit
(1)Checkco
nnector CN8AandCN
8C of the outdoor unit thermistor for
secure installation.
(2)Measure resistance of outdoor thermistorsTH1~4,6~8.
(3)Check the lead wiresofthermistorsTH1~4,6~8ontheoutdoor unit
control PCBfor open-circuit.
(4)Noabnormalityfound in above inspections (1)through(3).
(1)Correct the installation.
(2)Replace the outdoor unit thermistora
ssembly.
(3)Replace the outdoor unit thermistor assembly.
(4)Replace theoutdoorunit control PCB assembly.
Indoor/outdoor units in
complete shutdown
6time Outdoorun
it
DC Current
DC overcurrent error(1)IPMcon
tinuity check.
(2)Check the IPMan
dheat sink for secure installation.
(3)Checkthe outdoorunitf
anmotor forproperrotation.
(4)No abnormality foundi
nabove inspections (1)through (3).
(5)No abnormalityfound inabove inspections (1)through (4).
(1)Replace the outdoor unitIPM PCB assembly.
(2)Correct theinstallation (tighten thes
crews). Apply silicon grease.
(3)Replacetheoutdoor unit fanmotor.
(4)Replace the outdoor unit IPM PCBassembly.
(5)Replacethe compressor.
Indoor/outdoor units in
complete shutdown
7time Outdooru
nit
AC Current
AC overcurrenterror (1)Ensureunobstructed air flow from the outdoor unitair outlet.
(2)Check the outdooru
nit fan motor.
(1)Ensureunobstructedair flow from the outdoor unitair outlet.
(2)Check the outdoor unit fan motor.
AC currenter
ror when OFF(1)IPM continuity check(1)Replacethe outdoorIPMPWB
AC maximumcurrent error (1)Ensureunobstructedair flow from the outdoor unitair outlet.
(2)Check the outdoor unit fan motor.
(1)Ensureunobstructed air flow from the outdoor unitair outlet.
(2)Check the outdoorunitf
an motor.
AC current deficiency error (1)Replace the outdoor unitcontrolPC
Bassembly.
(2)Charge the specifiedamountofrefrigerant.
(3)Correct refrigerantclogs. (Stopva
lve,pipe,expansion valve)
(1)Replacethe outdoorunitcontrolP
CB assembly.
(2)Chargethe specifiedamountofr
efrigerant.
(3)Correctrefrigerant clogs. (Stop valve,pipe,expansionv
alve)
Indoor/outdoorunitsin
completeshutdown
Abnormal wire
check
Abnormal wire check error (1)Check theexpansion valve.(un
itA-C
)
(2)Arefour expansionvalvesc
onnectedbymi
stake
(3)Checkthe wiring between units.
(1)Replace the outdoor controlbo
ard assembly.
(2)Reattach
(3)Checkthe wiring between units.
Indoor/outdoorunitsin
complete shutdown
Outdooru
nit
DC Fan
Outdoor unit DCf
anrotation error(1)Check connectorCN3of the outdoor unit DCfan motorfo
rsecure installation.
(2)Check the outdoor unitf
an motor forproperrotation.
(3)Checkfuse FUSE5.
(4)OutdoorunitcontrolP
CB
(1)Correct the installation.
(2)Replace theoutdoor unit fanmotor.
(3)Replacetheoutdoor unit controlP
CB assembly.
(4)Replacethe outdoor unit controlPC
Bassembly.
Flashes in 1-sec intervals (normal) :1sec ON / 1sec OFF
X
:
:
OFF:Flashe
s3timesi
n0.2-sec intervals
8time
11 time
X
Heat exchangerthermistor short circuit
error
Outdoor temperature thermistor
short circuit error
Suction thermistor short circuit error
Thermistor Unit A-Cthermistor
shortcircuiterror
Compressor high temperature error
Temporary stop due to compressor
discharge overheat.
Temporary stop due to indoor unit
heat exchanger overheat.
Heat exchanger thermistoropen
circuit error
Outdoor temperature thermistor open
circuit error
Suctionthermistoropen circuit error
Suction thermistor open circuit error
Discharge thermistor opencircuit error
Thermistor Unit A - C thermistor open
circuit error
Temporary stop due to out door unit
heat exchanger overh
eat.
Operationl
amp(RED)
Clusterlam
p(BLUE)
-1
IPM pinlevel error (1)Check the IPM isa
ttached correcityto the outdoor unit IPM PWB. (1)Replace the outdoor unitIPMPW
Bassembly.
Indoor/outdoorunitsin
complete shutdown 12 time Operationl
amp(RED)
Clusterlamp(BLUE)
12 -0
Thermal fuse
in terminal board
Thermal fuse error in terminalboar
d
(for power supply)
(1)Check thethermal fuse in terminalboard(for Powers
upply)
(2)Check connectorCN5o
ftheoutdoor unit.
(1)Replace terminal board for Powersupply
(2)Replace theoutdoor unit control PCB assembly.
9time Operation lamp(RED)
Cluster lamp(BLUE)
-4
4wayv
alve error
orGas leakerror
(1)Check to make sureoutdoor unitthermistor TH2 (exchange) and TH3 (pipe
temperature) are installedincorrect portions.
(2)Checkifthe refigerant volume is abnomally low.
(3)Check the4-way valvefor proper operation.
(1)Correct the installation.
(2)Change the speccified amount of refrigerant.
(3)Replace the4-wayval
ve.
9
Cycle
temperature

3 – 4
Status of
indoor/outdoor
units
Indication by
LED1on
outdoor unit
*2
Indication on indoor unit
Content of diagnosis
Inspection location/method Remedy
Floor / ceilingWall
(Panel)
Lighting pattern at the time of timer lamp lighting
Main Sub
for 5 seconds Main categorySub category
Flashes in 1-sec intervals (normal) : 1sec ON / 1secOF
F
X
:
:
OFF : Flashes 3 times in 0.2-seci
ntervals
X
13 -0
-1 -2
14 -0
17 -0
-1
18 -0 19 -0
20 -0 30 -0
-1
Operation lamp(RED) Cluster lamp(BLUE) Operation lamp(RED)
Cluster lamp(BLUE)
Operation lamp(RED) Cluster lamp(BLUE) Operation lamp(RED) Cluster lamp(BLUE)
Operation lamp(RED)
Cluster lamp(BLUE) Operation lamp(RED) Cluster lamp(BLUE)
Operation lamp(RED) Cluster lamp(BLUE) Operation lamp(RED)
Cluster lamp(BLUE)
Operation lamp(RED) Cluster lamp(BLUE) Operation lamp(RED) Cluster lamp(BLUE)
Operation lamp(RED) Cluster lamp(BLUE) Operation lamp(RED) Cluster lamp(BLUE)
Operation lamp(RED)
Cluster lamp(BLUE)
Indoor/outdoor units in complete shutdown Indoor/outdoor units in complete shutdown Indoor/outdoor units in complete shutdown
DC compressor
Compressor startup error (1)Check the colors (red,white,orange)of the compressor cords for proper
connection. (PWB side, compressor side)
(2)Check if the IPM terminal resistance values are uniform. (3)Check if outdoor main relay (MRY1) turns on and voltage of both end of
the condenser (C10) has become DC380V.
(4)No abnormality found in above inspections(1)and(3). (5)No abnormality found in above inspections(1)and(4).
(1)Correct the installation. (U:Red,V:White,W:Orange) (2)Replace the outdoor unit control PWB assembl
y.
(3)Replace the outdoor unit control PWB assembl
y.
(4)Replace the outdoor unit control PWB assembl
y.
(5)Replace the compressor.
Compressor rotation error. (at 120º energizing) Compressor rotation error (at 180º energizing) Detection error of inverter current.
Outdoor unit Active Filter
Active Filter overvoltage error (1)Check the AC power supply voltage for fluc
tuation.
(2)No abnormality found in above inspec
tion (1).
(3)Replace the Active Filter.
(1)Connect stable power supply. (2)Replace the outdoor unit control PCB assembly.
Clock error (1)Check the clock for proper
inputt.
(1)Replace the outdoor unit control PCB assembly.
Indoor unit in operation Outdoor unit in complete shutdown Indoor unit in operation Outdoor unit in complete shutdown Indoor/outdoor units in operation Indoor/outdoor units in operation
Wires between units
Serial open-circuit (1)Check the wires between units.
(2)Check voltage between N and 1 the indoor/outdoor unit terminal boards.
(1)Connect stable power supply. (2)Replace the outdoor unit control PCB assembly.
(1)Check the wires between units. (2)Check the outdoor unit fuse. (3)Check 15-V,13-V and 5-V voltages on the PCB.
Check resistance between IPM terminals.
(4)Check pins No.5 and 8 of connector CN3 o
f the outdoor
unit fan motor
for short-circuit.
(5)Outdoor unit control PCB.
(1)Correct the wiring. (2)Replace the fuse/outdoor unit control PCB assembly. (3)Replace the outdoor unit control PCB assembly. (4)Replace the outdoor unit fan motor. (5)Replace the outdoor unit control PCB board.
Wires between units
Serial short-circuit (1)Check the wires between units. (1)Correct the wiring. Serial erroneous wiring (1)Check the wires between units. (1)Correct the wiring.
Indoor unit fan
Indoor unit fan error (1)Check the indoor fan motor for proper rotating operation. (Check fan lock.)
(2)Check the lead wire of the indoor fan motor for open-circuit. (3)Check connector of the indoor unit fan motor for secure installation. (4)No abnormality found in above inspections (1)through (3).
(1)Replace the indoor fan motor. (2)Replace the indoor fan motor. (3)Correct the installation of CN3 of the indoor fan motor. (4)Replace the indoor unit control PCB.
Indoor unit control PCB
EEPROM data error (EEPROM read data error) (1)Replace the indoor unit control PCB.
Drainpumpunit
Drain pump unit error (1)Check connector CN2 and CN10. (1)Replace the Drain pump unit unit.
(2)Re-insertion of CN2 and CN10.
13 time
14 time
X
X X
X
Erroneous wiring
Operation lamp(RED)
Cluster lamp(BLUE) -4
low valtage error (1)Check the AC power supply valtage for fluntuation. (1)Conect stable power supply.
(2)Replace tfe outdoor unit control PCB assembl
y.
3
-
(1)Check the circuit of detection of inverter current. (1)Replace the outdoor unit control PCB assembl
y.

3 – 5
CHECK METHOD
CAUTION: CHECKING PRINTED CIRCUIT BOARDS (PWB)
Non-insulated control circuit
The GND terminals of the low-voltage circuits (control circuits for
microcomputer and thermistors and drive circuits for expansion valve
and relays) on the control printed circuit board (PWB) are connected
to the compressor drive power supply (370-VDC negative terminal).
Therefore, exercise most caution to prevent electric shock.
If a measuring instrument used for the test is grounded, its chassis
(ground) has the same electric potential as the 0-V probe. Since non-
insulated circuits have the following voltage potential difference from
the ground, connection of the grounding wire results in a short-circuit
between the 0-V line and the ground, thus allowing an excessive cur-
rent to flow to the tester to cause damage.
If the sheaths of the thermistor lead wires or expansion valve lead
wires inside the outdoor unit become damaged due to pinching by the
front panel or other metal parts or contacting a pipe, a high voltage can
flow and destroy the circuits. To prevent these problems, carefully conduct assembly work.
Reason
The oscilloscope (chassis ground) has the same electric potential as the 0-V probe. The entire electronic control section of the outdoor
unit has a voltage potential difference from the ground. When the oscilloscope is setup, the 0-V line and the ground voltage (ground) will
be short circuited, resulting in an excessive current flow to cause damage to the oscilloscope or indoor electric circuits.
CAUTION: when attaching or removing the board
When operating only the outdoor unit (cooling 48.3 Hz fixed mode) to make the outdoor unit run in cooling mode, apply a voltage of 220 ~
240V AC to L and N on the terminal board and push the pump down switch (SW1). (Avoid operating the outdoor unit alone for long periods
of time.)
Do not touch the
cabinet or bring metal
parts into contact with
the cabinet.
Danger!!
Do not connect
the grounding
wire.
(D)
(D)
0
500k
400k
300k
200k
100k
0
-20 0 20 60 80 100 120
3.06k
5.78k
2.28k
1.72k
40k
30k
20k
10k
0
-20 0 20 60
40
TH1 compressor thermistor
(CN8A 1 - 2 )
TH2 - TH4
TH6 - TH8
Temperature (ºC)
Temperature ( ºC)
25ºC resistance
45 k
Resistance ( )
Resistance ( )
0 ºC resistance
14.5 k
25
ºC resistance
4.431 k
4.17k
Figure 2 Temperature properties of outdoor thermistors
Connector
CN8A Connector
CN8C
1
TH2 : Heat exchanger pipe thermistor (CN8A 3 - 4 )
TH3 : Outdoor temp. thermistor (CN8A 5 - 6 )
TH4 : Suction thermistor (CN8A7-8)
TH6 : Thermistor unit A (CN8C 1 - 2 )
TH7 : Thermistor unit B (CN8C 3 - 4 )
TH8 : Thermistor unit C (CN8C 5 - 6 )
186