Sharp AE-X26FR-N User manual

CHAPTER 1. SPECIFICATION
[1] SPECIFICATION............................................ 1-1
[2] EXTERNAL DIMENSION............................... 1-2
[3] WIRING DIAGRAM ........................................ 1-3
[4] ELECTRICAL PARTS .................................... 1-3
CHAPTER 2. EXPLAMATION OF CIRCUIT AND OP-
ERATION
[1] BLOCK DIAGRAMS....................................... 2-1
[2] MICROCOMPUTER CONTROL SYSTEM.... 2-3
[3] FUNCTION..................................................... 2-8
CHAPTER 3. FUNCTION AND OPERATION OF PRO-
TECTIVE PROCEDURES
[1] PROTECTION DEVICE FUNCTIONS AND
OPERATIONS................................................ 3-1
[2] AIR CONDITIONER OPERATION IN
THERMISTOR ERROR ................................. 3-3
[3] THERMISTOR TEMPERATURE CHAR-
ACTERISTICS ............................................... 3-5
[4] HOW TO OPERATE THE OUTDOOR
UNIT INDEPENDENTLY ...............................3-6
[5] GENERAL TROUBLESHOOTING CHART........3-6
[6] MALFUNCTION (PARTS) CHECK METH-
OD .................................................................3-8
[7] OUTDOOR UNIT CHECK METHOD...........3-10
[8] TROUBLESHOOTING GUIDE ....................3-13
CHAPTER 4. REFRIGERATION CYCLE
[1] FLOW FOR REFRIGERANT.........................4-1
[2] STANDARD CONDITIONS............................4-1
[3] PERFORMANCE CURVES...........................4-2
CHAPTER 5. DISASSEMBLING PROCEDURE
[1] INDOOR UNIT...............................................5-1
[2] OUTDOOR UNIT...........................................5-5
REOLACEMENT PARTS LIST
SERVICE MANUAL
CONTENTS
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.
TopPage
AYXP26FRN
SPLIT TYPE
ROOM AIR CONDITIONER
INDOOR UNIT
AY-XP26FR-N
OUTDOOR UNIT
AE-X26FR-N
MODELS
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.

AYXP26FRN
1 – 1
AYXP26FRN Service Manual
CHAPTER 1. SPECIFICATION
[1] SPECIFICATION
1. AY-XP26FR-N / AE-X26FR-N
NOTE: The conditions of star(✩) marked items sre ‘ISO151’ : 1994(E), condition T1.
MODEL INDOOR UNIT OUTDOOR UNIT
ITEMS AY-XP26FR-N AE-X26FR-N
Cooling capacity(Min. ~ Max.) kW 2.6 (0.9 - 3.0)
Heating capacity(Min. ~ Max.) kW 3.6 (0.9 - 5.0)
Moisture removal(at cooling) Liters/h
Electrical data
Phase Single
Rated frequency Hz 50
Rated voltage V 230
Rated current✩
(Min - Max.)
Cool A 3.3 (0.8 - 4.6)
Heat A 4.1 (0.7 - 6.5)
Rated input✩
(Min - Max.)
Cool W 650 (150 - 900)
Heat W 900 (130 - 1400)
Power factor✩Cool % 86
Heat % 95
Compressor Type Hermetically sealed rotary type
Model 5RS092XDF
Oil charge 320cc (RB68A or Freol Alphc 68M)
Refrigerant system Evaporator Louver Fin and Grooved tube type
Condenser Corrugate Fin and Grooved tube type
Control Expansion valve
Refrigerant (R410A) 1000g
De-lce system Micro computer controled reversed systems
Noise level
(at cooling)
High dB(A) 43 48
Low dB(A) 34 -
Soft dB(A) 28 -
Fan system
Drive Direct drive
Air flow quantity
(at cooling)
High m3/min. 9.9 22
Low m3/min. 7.7 –
Soft m3/min. 6.0 –
Fan Cross flow fan Propeller fan
Connections
Refrigerant coupling Flare type
Refrigerant tube size Gas, Liquid 3/8", 1/4"
Drain piping mm O.D φ18
Others
Safety device Compressor: Thermal protector
Fan motors: Thermal fuse
Fuse, Micro computer control
Air filters Polypropylene net (Washable)
Net dimensions Width mm 810 730
Height mm 285 540
Depth mm 240 250
Net weight kg 11 36

AYXP26FRN
1 – 2
[2] EXTERNAL DIMENSION
1. INDOOR UNIT
2. OUTDOOR UNIT
CRMC-A442JBE0
R03(AAA) 2PCS.
SHARP CORPORATION
INVERTER AIR CONDITIONER
22.0
58 18.5
175
790
240
285
810
250
165
167.5
136
81
730
72
540
299 324
515
12
37.5
4.5
58
135
14

AYXP26FRN
1 – 3
[3] WIRING DIAGRAM
1. INDOOR UNIT
2. OUTDOOR UNIT
[4] ELECTRICAL PARTS
1. INDOOR UNIT 2. OUTDOOR UNIT
N
1
N
1
2
N
1
2
WIRING DIAGRAM <CB878>
INDOOR UNIT OUTDOOR UNIT
TERMINAL BOARD1
POWER
SUPPLY
SINGLE
PHASE
GREEN-YELLOW
BLUE
BLACK
LOUVER MOTOR
(TOP)
LOUVER MOTOR
(BOTTOM)
ROOM TEMP.
THERMISTOR
PIPE TEMP.
THERMISTOR
TH1
TH2
YELLOW
ORANGE
CNA
CNB
R76
IN OUT
S
N
BLUE
BLACK
RED
NF1 DB1
C14A
FU1
250V
3.15A
FU2
250V
2A
NR1
SSR
RY1
C23
NF2
C28
CN5 C98
C99
CN1
C97
C96
FAN MOTOR
TERMINAL BOARD 2 TERMINAL BOARD
CLUSTER
GENERATOR
POWER
SUPPLY UNIT
CN2
CN3
BCN1
BCN3
BCN201 CN102
BCN101
CN101
DISPLAY
BOARD
UNIT
RECEIVER
BOARD
UNIT
CONTROL BOARD UNIT
SERIAL
SIGNAL
CIRCUIT
EVAPORATOR
LED INDICATION FOR SELF-DIAGNOSIS
Abnormal contents
Temperature
Indicator
Blinking No.
1
2
5
6
7
9
11
13
14
17
18
Short circuit of the Thermistor
Overheat error (compressor and cycle)
Open circuit of the Thermistor
Abnormal DC current
Abnormal AC current
Abnormal outdoor fan motor
Abnormal Thermistor or four way valv
Abnormal PAM voltage and PAM clock signal
Open circuit of serial signal line
Short circuit of serial signal line
19 Abnormal fan motor of indoor unit
Rotation error of the compressor or compressor lock
<Indication of the abnormal condition>
LED indicator will blink, if the set is in abnormal condition.
DESCRIPTION MODEL REMARKS
Indoor fan motor MLB084 DC Motor
Indoor fan motor
capacitor
——
Transformer — —
FUSE1 — QFS-GA052JBZZ (250V, 3.15A)
FUSE2 — QFS-GA051JBZZ (250V, 2A)
DESCRIPTION MODEL REMARKS
Compressor 5RS092XDF D.C. brush-less motor
Outdoor fan motor ML-A902 DC Motor
Outdoor fan motor
capacitor
——
Fuse1 — QFS-CA001JBZZ(250V, 20A)
Fuse2 — QFS-GA052JBZZ(250V, 3.15A)
Fuse3 — QFS-GA051JBZZ(250V, 2A)
Fuse4 — QFS-GA064JBZZ(250V, 1A)
Fuse5, 6 — QFS-CA002JBZZ(250V, 15A)

AYXP26FRN
2 – 1
AYXP26FRN Service Manual
CHAPTER 2. EXPLAMATION OF CIRCUIT AND OPERATION
[1] BLOCK DIAGRAMS
1. Indoor unit
Louvre motor drive circuit(upper)
Louvre motor drive circuit(lower)
LED drive circuit
Flow direction control (louver motor upper)
Flow direction control (louver motor lower)
LED display
AC power
Rectification circuit
CPU
Sub
CPU
3.15A
Fuse
Serial signals
2A
Fuse
DC power supply circuit
Fan motor PWM control circuit
Rotation pulse input circuit
AC clock circuit
Remote controller signal reception circuit
Buzzer drive circuit
CPU reset circuit
CPU oscillator circuit
Room temp. detect circuit
Heat exchanger pipe thermo circuit
EEPROM
Select circuit
Serial I/O circuit
Power supply relay drive circuit
Auto restart circuit
Test run circuit
Auxiliary mode
Power on circuit
Cluster generator drive circuit
Cluster generator sensor circuit
Indoor fan motor
Fan motor pulse detect
Wireless remote control operation
Audible operation confirmation
Room temp. thermistor
Heat exchanger pipe thermistor
Louvre angle, fan speed
Wireless, preheat, Model select
Indoor/outdoor control signal I/O
Outdoor unit power supply on/off control
Test run (forced operation)
Auxiliary mode button ON/OFF
Self diagnostics, fault diagnosis
Cluster generator
Unit-unit wiring
(AC power and
serial signals)

AYXP26FRN
2 – 2
2. Outdoor unit
CPU
20A
protection
Expantion valve drive circuit Expantion valve
Suction temp. thermo. circuit Suction pipe thermistor
2-way valve temp. thermo. circuit 2-way valve thermistor
3.15A
protection
15A
protection
Power supply circuit
CPU oscillator circuit
DC overvoltage detection circuit
Outdoor fan drive circuit
4-way valve relay drive circuit
Power transistor module drive circuit
Serial I/O circuit
CPU reset circuit
Position detection circuit
AC overcurrent detection circuit
Compressor thermo circuit
Heat exchanger pipe thermo circuit
Outdoor temp. thermo. circuit
LED drive circuit
Test mode circuit
Power factor
converter circuit
Filter
circuit
Smoothing
circuit
Unit-unit wiring (AC power
and serial signals)
Outdoor fan
4-way valve
Power transistor module
Compressor
Current transformer
Compressor thermistor
Heat exchanger pipe thermistor
Outdoor temperature thermistor
LED

AYXP26FRN
2 – 3
[2] MICROCOMPUTER CONTROL SYSTEM
1. Indoor unit
1.1. Electronic control circuit diagram

AYXP26FRN
2 – 4
1.2. Display circuit diagram
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ហᢃ᠃
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ᘙᅆؕெ
Ӗήؕெ
èƸȆǹȈȝǤȳȈǛᘙƢ
D102
LED105
LED102
LED103
LED104
D101
D103
1SS270A
1SS270A
1SS270A
e
d
b
a
1 / 2W 1 / 2W 1 / 2W
R104
1/2W
180
R103R102R101
180180180
LED109
9(H2)
7(G2)
12(F2)
5(E2)
NC
g
f
15(B1)
16(A1)
6(D2)
8(C2)
10(B1)
11(A2)
4(H1)
17(G1)
18(F1)
1(E1)
2(D1)
3(C1)
NC
f
e
d
c
b
a
e
d
c
b
a
g
B2
H2
C2
13(COM)
(COM)14
A1
G1
D1
E1
F1 B1
H1
C1
A2
G2
D2
E2
F2
SL3264
1/2W
180
R107, R108, R110, R111
1W
180
R105, R106, R109
R111 R110 R109 R108 R107 R106 R105
5V
BCN201
3 1 2
R201
47 1/2W
1
2
3
BCN101
5V
8 7 6 5 4 3 2 1
+
C202
0.1μ
50V
C201
33μ
10V
IC201
a
b
c
d
e
f g
CN102
CN101
6 9 8 7 5 4 3
11
10
2
1
SHEMATIC DRAWING OF DISPLAY
LED101

AYXP26FRN
2 – 5
1.3. Printed wiring board

AYXP26FRN
2 – 6
2. Outdoor unit
2.1. Electronic control circuit diagram
9.53KF
R84
0V
Q10
0V
15V
0.01μ
10V
47μ
6.8KJ
R85
C77
R86
C78
2A
250V
FU3
7
5
4
3 2
1
0V
CN3
0.1μ
400V
C29
0V
5V
R83
10K
RY1
1
2
3
4
5
6
0V
IC7
M
a
b
5V
10K
10K
0V
j
0V
JP1
JP2
c
JPF
0V
100μ
C94
10V
C95
0.1μ
0.1μ
10K
R37 1K
R38 1K
R36 1K
0V U
V
W
C34
C35
C36
1000P x 3
D7
D6
TR1
R29
4.7K
68
18V - P
C85
0.1μ
R82
680μ
C19
IC3
R27
1W
IC4
5V
0V
R22
25V
C20R21
22K
R24
10K
R87
150μ
C84
D14
9
35V
0V -P
35V
R93
R94
R92
D20
C98
3
2
1
R78
IC5
C33
R77
50V 1μ
R79
100
0.1μ
C32
0V
QS
T
R
Q3
R
S T
9
Q
JP10
1 2 3 4 5 6 7 8
8
5
6
11
10
7
1K
10K
9
8
Q9
0V
2.2K
R32
R31
0V
R33
IC6
8 7
5
6
1
2
4
3
CNE
5V
R30
4
3
1 2
4.7K
13V
CN12
EXPANSION
VALV COIL
MRY1
13V
C38
0.1μ
24 27
23
22
21
28
18
16 13
15
12
4
10
7
9
6
1
3
10K
R45
5V
100μ
C47
1000P
C42
C48
10V
0.1μ
0V
IPM
330μ 25V
C37
100μ
25V
C49
0.1μ
25V
C51
0.1μ
C54
100μ
25V
C53
0.1μ
0.1μ
0.1μ C55
0.1μ
C57
C45
0.1μ
C56
D9
D10
100μ
C52
D8
C50
VWFB
VUFS
VUFB
WN
VN
UN
WP
VPI
VWFS
VPI
VPI
VP
VVFS
VVFB
UP
VNC
F0
VNI
C41
1000P
1000P
C40
C43
1000P
C44
1000P
C39
1000P
1K
R46
ZD4
16V 10μ x 5
C70 ~ 74
10K x 5 R63 ~ 67
0V
0V
CN8
10
6 5 4 3 2 7 9 8
0.01μ x 5 C65 ~ 69
5V
TH2
TH3
TH4
TH5
1
330K
R100
R107
PC4
330
Q7
KRC105S
1000P
C59
1/2W
R51 ~ 53
IPM
c
6
5
8
5W
R49
2 3
TLP351
j
M
270KD
R126
255KF
250V
FU5
0.02
5V
15A
470KF x 3
CIN
CF0
26
25
31
35
150 R110
250V
FU4
1A
j
1KV
C27
220PF
C15
50V
10μ
R17
STR -L
472
IC2
1/2W 1M
1/2W 1M
1/2W 1M
1
D5
1/2W 1M 1/2W 1M 1/2W 1M
R8 R9 R10
R11 R12 R13
3.3K
R20
2SA1586G
Q1
ZD1
0V
470P
C17
R14
R18
1.5K
3300P
D4
OCP/FB
1~4
8
710 96
Source
GND
Drain
Vcc
C18
680
R16
R15
C16
D15
1.6
1.6
3
D3
R19
15V
PC3
23
4
1
0.01μ
C81
R146
100K
e
d
5V5V
FU2
R105
0V
22K
3.3K
R106
C83
1000P
0.01μ
C82
Q6
KRC102S
10V
C79
R91 R147
10K
R90
D2
1.0KF 220μ
2.2K
R111
DB2
Q5
TERMINAL BOARD
N
1
WH WH
GR
R89
0V
BLUE
BROWN
YELLOW GREEN/
T2
T1
1
2
L3 L4
13
3
4
SA1
NR1
T4
R1
1/2W
1M
275V
1μF
275V 1μF
C2
4
2
1μF 275V
CT1
T6
510K
1/4W
R88
1/4W
510K
C1 C3
OUT
IN
PTC
MRY1
GR GR
T5
DB1
18V-P
4700pF
250V
4700pF
250V
4700pF
250V
4700pF
250V
R4
3.3K
D1 0.1μ
C13
1K 2W 2W
1K 1K
2W
4700P
250V C12
+
420V 420V
+
3.15A
250V
R101
R102
R103
R104
1/2W 47K x 2
R101, 102
1W 47K x 2
R103, 104
T10 T11
PC81716NIP
5V
0V
R55
R56
R54
C60
0.1μ
25V
R99 100
0.1μ
C86
15K R112
C61
50V
330P
330P
50V
C62
R57 100
R58 100
R59 100
C63
330P
50V
12
6
7
8
9
10
0.1μ
C64
25V
11 4
3
5
IC8
KIA339
1
5V
0V
0.01μ
C97
UVN
W
5V
0V
C88
1000P
N
1K
R116
RY1
120
1/2W
0.033μ
NR2
275V
CN4
C26 R28 3
1
d e
D24
2
RED
T3
R129
10K
T12
T13
250V
20A
FU1
R34
R35
JP16
5V
5V
0.1μ
C93
100μ
10V
C30
5V
0V
JP9
JP8
JP7
32 31 30 29 28 27 26 25 24 23 22 21 20
10111213141516171819 1
2
34
5
6
89 7
52 53 54 55 56 57 58 59 60 61 62 63 64
51504948474645444342414039383736353433
P07
P10
P11
P12
P13
P14
P15
P16
P17
P20
P21
P22
P23
P24
P25
P26
P27
VSS
P30
(U)
P44
P45
P46
P50
P51
P52
P53
P54
P55
P56
P57
AVCC
AVR
AVSS
P60
P61
P62
P63
MD0
(B) (O)
(Y)
(W)
IC1
RST MD1 MD2 X1 X0 VSS P00 P01 P02 P03 P04 P05 P06 P31
P32 P33 P34 P35 VCC C P36 P37 P40 P41 P42 P43
(X) (V)
(Y) (W) (Z)
(U)
(V)
(W)
R133 100
R132 100
R137 100
R136 100
R135 100
R134 100
5V
5V
2.2K
R73 LED1
10K
R155 10K
R154
5V
(CN)
4
1
2 3
OSC1 4MHz
0V
10K
10K
20
JP17
N
35
VNO
20.5KF
20.5KF
20.5KF
0V
PS21563 or 21564
FU6
250V
15A
1000P
C46
0V
0V
C4A
C5A
C7A
C6A
R41 R42
R43
10
2W
2K
680P
6.8K
6.8K
270
270
15V
D11 6.8KF x 5
R68 ~ 72
R47, 48
33 x 2
1/4W
1/4W 33 x 2
R47A, 48A
5V
C
(R)
S
(C)
R
FC3 FC4
YELLOW
GREEN/
EARTH
U32
V33
W34
T7
T8
T9
N
FC1
FC2
FB
D12
D13
R61
1.8K
R60
1.8K
R62
1.8K
1.8K
R115
R114
1M
14
13
2
0V -P
D23
D22
D21
15V
0V
0.022μ
C58
ZD3
R50
1.8KF
VALV COIL 4-WAY
PC1
PC817XP3
3
1
2.7K
R75
b
R74
a
1000P
C75
0V
4.7K
5V
R76
56K
4
1
2
4
32
PC853HXP
PC2
4.64KF
R26
R23
68K
C21
0.033μ
1.65KF
R25
1.5K
150μ
10K
10K
C23
0.1μ
7805
R81
10K R144
C76
1000P
5V
Q4
23.7KF
23.7KF
R6
R7 R128
13KF
R127
13KF
P
0.33μ
C14
630V
270KD
1/2W
R125
1/2W
R2
1/2W
300KF
1/2W
R5
750μ
C10
C9
750μ
(THERMISTOR CIRCUIT)
(THERMISTOR)
(SERIAL I/O CIRCUIT)
(PAM OVER CURRENT CIRCUIT)
(EEPROM CIRCUIT)
(4 - WAY VALVE CIRCUIT)
(FAN MOTOR CIRCUIT)
(FAN MOTOR)
(RESET CIRCUIT) (SWITCHING POWER
SUPPLY CIRCUIT)
KID65004AP
PST993D
KRA106S
KRC105S
KRC105S
KRA106S
(DC OVERCURRENT CHECK CIRCUIT)
MONITOR
(FOR DEBUG)
CND
(FRASH WRITER
CONNECTOR)
(LED CIRCUIT)
DETECT CIRCUIT) (ROTOR POSITION
+
C4
C5
C7
C6
2.7kF
6.8KF
13V
0.1μ
C31
C
19.1KF
R113

AYXP26FRN
2 – 7
2.2. Printed wiring board

AYXP26FRN
2 – 8
[3] FUNCTION
1. Functions
1.1. Startup control
The main relay remains off during the first 45 seconds (first safety
time) immediately after the power cord is plugged into an AC outlet in
order to disable outdoor unit operation and protect outdoor unit electric
components.
1.2. Restart control
Once the compressor stops operating, it will not restart for 180 sec-
onds to protect the compressor.
Therefore, if the operating compressor is shut down from the remote
control and then turned back on immediately after, the compressor will
restart after a preset delay time.
(The indoor unit will restart operation immediately after the ON switch
is operated on the remote control.)
1.3. Cold air prevention control
When the air conditioner starts up in heating mode, the indoor unit fan
will not operate until the temperature of the indoor unit heat exchanger
reaches about 23?C in order to prevent cold air from blowing into the
room.
Also, the indoor unit fan operates at low speed until the temperature of
the indoor unit heat exchanger reaches about 38?C so that people in
the room will not feel chilly air flow.
1.4. Odor prevention control
When the air conditioner starts up in cooling mode, the discharged air
temperature is lowered slightly, and for the reduction of unpleasant
odors the operation of the indoor unit fan is delayed 60 seconds if the
automatic fan speed mode in cooling mode is set.
1.5. Indoor unit heat exchanger freeze prevention control
If the temperature of the indoor unit heat exchanger remains below
0°C for 4 consecutive minutes during cooling or dehumidifying opera-
tion, the compressor operation stops temporarily in order to prevent
freezing.
When the temperature of the indoor unit heat exchanger rises to 2°C
or higher after about 180 seconds, the compressor restarts and
resumes normal operation.
1.6. Outdoor unit 2-way valve freeze prevention control
If the temperature of the outdoor unit 2-way valve remains below 0°C
for 10 consecutive minutes during cooling or dehumidifying operation,
the compressor operation stops temporarily in order to prevent freez-
ing.
When the temperature of the 2-way valve rises to 10°C or higher after
about 180 seconds, the compressor restarts and resumes normal
operation.
When the compressor operation stops temporarily, LED1 on the out-
door unit flashes twice.
1.7. Indoor unit overheat prevention control
During heating operation, if the temperature of the indoor unit heat
exchanger exceeds the indoor unit heat exchanger overheat preven-
tion temperature (about 45 to 54°C) which is determined by the operat-
ing frequency and operating status, the operating frequency is
decreased by about 4 to 15 Hz. Then, this operation is repeated every
60 seconds until the temperature of the indoor unit heat exchanger
drops below the overheat protection temperature.
Once the temperature of the indoor unit heat exchanger drops below
the overheat protection temperature, the operating frequency is
increased by about 4 to 10 Hz every 60 seconds until the normal oper-
ation condition resumes.
If the temperature of the indoor unit heat exchanger exceeds the over-
heat protection temperature for 60 seconds at minimum operating fre-
quency, the compressor stops operating and then restarts after about
180 seconds, and the abovementioned control is repeated. When the
compressor operation stops temporarily, LED1 on the outdoor unit
flashes twice.
1.8. Outdoor unit overheat prevention control
During cooling operation, if the temperature of the outdoor unit heat
exchanger exceeds the outdoor unit heat exchanger overheat preven-
tion temperature (about 55°C), the operating frequency is decreased
by about 4 to 15 Hz. Then, this operation is repeated every 60 sec-
onds until the temperature of the outdoor unit heat exchanger drops to
about 54°C or lower.
Once the temperature of the outdoor unit heat exchanger drops to
about 54°C or lower, the operating frequency is increased by about 4
to 10 Hz every 60 seconds until the normal operation condition
resumes.
If the temperature of the outdoor unit heat exchanger exceeds the out-
door unit heat exchanger overheat protection temperature for 120 sec-
onds at minimum operating frequency, the compressor stops operating
and then restarts after about 180 seconds, and the abovementioned
control is repeated. When the compressor operation stops temporarily,
LED1 on the outdoor unit flashes twice.
1.9. Compressor overheat prevention control
If the temperature of the compressor exceeds the compressor over-
heat prevention temperature (110°C), the operation frequency is
decreased by about 4 to 10 Hz. Then, this operation is repeated every
60 seconds until the temperature of the compressor drops below the
overheat protection temperature (100°C).
Once the temperature of the compressor drops below the overheat
protection temperature, the operating frequency is increased by about
4 to 10 Hz every 60 seconds until the normal operation condition
resumes.
If the temperature of the compressor exceeds the overheat protection
temperature (for 120 seconds in cooling operation or 60 seconds in
heating operation) at minimum operating frequency, the compressor
stops operating and then restarts after about 180 seconds, and the
abovementioned control is repeated. When the compressor operation
stops temporarily, LED1 on the outdoor unit flashes twice.
1.10. Startup control
When the air conditioner starts in the cooling or heating mode, if the
room temperature is 2°C higher than the set temperature (in cooling
operation) or 3.5°C lower (in heating operation), the air conditioner
operates with the operating frequency at maximum. Then, when the
set temperature is reached, the air conditioner operates at the operat-
ing frequency determined by fuzzy logic calculation, then enters the
normal control mode after a while.
Compressor operation
ON operation on
remote control
OFF operation on
remote control
Compressor ON
Compressor ON Compressor can
turn ON
Compressor remains OFF
for 180 seconds
Indoor unit heat exchanger temperature
38ºC
23ºC
35ºC
21ºC
Set fan speed
Indoor unit fan at low speed
Indoor unit fan in non-operation

AYXP26FRN
2 – 9
1.11. Peak control
If the current flowing in the air conditioner exceeds the peak control
current (see the table below), the operation frequency is decreased
until the current value drops below the peak control current regardless
of the frequency control demand issued from the indoor unit based on
the room temperature.
1.12. Outdoor unit fan delay control
The compressor stops immediately after cooling, dehumidifying or
heating operation is shut down, but the outdoor unit fan continues
operation for 50 seconds before it stops.
1.13. Defrosting
1.13.1 Reverse defrosting
The defrost operation starts when the compressor operating time
exceeds 20 minutes during heating operation, as shown below, and
the outside air temperature and the outdoor unit heat exchanger tem-
perature meet certain conditions. When the defrost operation starts,
the indoor unit fan stops. The defrost operation stops when the out-
door unit heat exchanger temperature rises to about 13°C or higher or
the defrosting time exceeds 10 minutes.
1.14. ON timer
The ON timer can be activated by pressing the ON timer button. When
the ON timer is activated, the operation start time is adjusted based on
fuzzy logic calculations 1 hour before the set time so that the room
temperature reaches the set temperature at the set time.
1.15. OFF timer
The OFF timer can be activated by pressing the OFF timer button.
When the OFF timer is set, the operation stops after the set time.
When this timer is set, the compressor operating frequency lowers for
quieter operation, and the room temperature is gradually varied after
one hour (reduced 1?C three times (max. 3?C) in heating, or
increased 0.3?C three times (max. 1?C) in cooling or dehumidifying
operation) so that the room temperature remains suitable for comfort-
able sleeping.
1.16. Power ON start
If a jumper cable is inserted in the location marked with HAJP on the
indoor unit control printed circuit board (control PCB), connecting the
power cord to an AC outlet starts the air conditioner in either cooling or
heating mode, which is determined automatically by the room temper-
ature sensor.
When a circuit breaker is used to control the ON/OFF operation,
please insert a jumper as described above.
1.17. Self-diagnostic malfunction code display
1.17.1 Indoor unit
1) When a malfunction is confirmed, all relays turn off and a flashing
malfunction code number is displayed to indicate the type of mal-
function.
When the air conditioner is in non-operating condition, holding
down the emergency operation switch for more than 5 seconds
activates the malfunction code display function.
The operation continues only in the case of a serial open-circuit,
and the main relay turns off after 30 seconds if the open-circuit con-
dition remains.
In the case of a serial short-circuit, the air conditioner continues
operating without a malfunction code display, and the main relay
turns off after 30 seconds if the short-circuit condition remains.
The malfunction information is stored in memory, and can be
recalled later and shown on display.
2) The self-diagnostic memory can be recalled and shown on the dis-
play by stopping the operation and holding down the emergency
operation button for more than 5 seconds.
3) The content of self-diagnosis (malfunction mode) is indicated by a
flashing number.
(For details, refer to the troubleshooting section.)
1.17.2 Outdoor unit
If a malfunction occurs, LED1 on the outdoor unit flashes in 0.2-sec-
ond intervals as shown below.
1.18. Information about auto mode
In the AUTO mode, the temperature setting and mode are automati-
cally selected according to the room temperature and outdoor temper-
ature when the unit is turned on.
During operation, if the outdoor temperature changes, the temperature
settings will automatically slide as shown in the chart.
Peak control current
Cooling operation Heating operation
Approx. 6.3 A Approx. 8.0 A
20 min or more 20 min or more 20 min or more
Defrosting
Max. 10 min
Defrosting
Max. 10 min
Start of
heating
operation
Heating operation
Set temperature
Activation of
OFF timer
1 hour
later
Max.
1.5 hours
later
Max.
2 hours
later
Timer setting
reached
1 hour
later
Max.
1.5 hours
later
Max.
2 hours
later
Timer setting
reached
Activation of
OFF timer
Set temperature
-1
O
C
-1
O
C
-1
O
C
0.3
O
C0.3
O
C0.3
O
C
Cooling/dehumidifying operation
1 sec 1 sec 0.6 sec
ON
OFF
(Example) Compressor high temperature abnormality
Modes and Temperature Settings
the figures in ( ) are temperature settings

AYXP26FRN
2 – 10
1.19. Airflow control
The airflow control holds the two upper and lower louvers at special
positions during operation to prevent discharged air from directly blow-
ing onto people in the room.
1.19.1 Cooling/dehumidifying operation
1) When the airflow button is pressed
The upper louver is set at an upward angle to send the air along the
ceiling.
1.19.2 Heating
1) When the airflow button is pressed
The lower louver is positioned straight downward to send the air along
the wall.
The upper louver is set at a downward angle.
1.19.3 Adjustment of Coanda-effect angle from remote
control
The louver direction can be finely adjusted to create a Coanda airflow
when the upper and lower louvers are set to " " in cooling or
dehumidifying operation, or to " " in heating operation.
If it is difficult to produce a Coanda airflow along the ceiling in cooling
operation because the air conditioner is not installed close to the ceil-
ing or there is a beam or lighting fixture on the ceiling, or if it is difficult
to produce a Coanda airflow along the wall in heating operation
because furniture is located below the air conditioner, perform fine
adjustment of the louver direction by following the procedure
described below and obtain a desirable airflow.
1) Adjustment of Coanda airflow direction in heating oper-
ation
1) Set the operation mode to Heating and the Airflow Up/Down to
" " using the remote control, and operate the air conditioner.
2) With the remote control pointed away from the main unit to disallow
signals from reaching the main unit, press the Stop button.
3) When the Airflow Up/Down button is held down for more than 5
seconds, the display shows " ".
4) Now, the air conditioner is ready for adjustment of the Coanda air-
flow direction. Each pressing of the Airflow Up/Down button
changes the display on the main unit in the order shown in the table
below, and the louver direction changes accordingly. Adjust the
direction while checking the actual louver angle and airflow direc-
tion.
5) After the adjustment is completed, press the Stop button on the
remote control.
2) Adjustment of Coanda airflow direction in cooling oper-
ation
1) Set the operation mode to Cooling and the Airflow Up/Down to
" " using the remote control, and operate the air condi-
tioner.
2) With the remote control pointed away from the main unit to disallow
signals from reaching the main unit, press the Stop button.
3) When the Airflow Up/Down button is held down for more than 5
seconds, the display shows " ".
4) Now, the air conditioner is ready for adjustment of the Coanda air-
flow direction. Each pressing of the Airflow Up/Down button
changes the display on the main unit in the order shown in the table
below, and the louver direction changes accordingly. Adjust the
direction while checking the actual louver angle and airflow direc-
tion.
5) After the adjustment is completed, press the Stop button on the
remote control.
1.20. Difference of operation in Auto and Manual modes
In the Auto mode, the temperature setting is automatically determined
based on the outside air temperature. In addition, the air conditioner
operation differs from the operation in the Manual mode as explained
below.
1.20.1 Difference relating to set temperature
1.21. Limitation on operating frequency in heating opera-
tion
If any of the following conditions is met 1 minute after operation star-
tup, the operating frequency is decreased to 90% in order to reduce
the operating sound and save energy in exchange for room warming
speed.
1) First operation after power ON
2) Outside air temperature is 3°C or higher
3) Room temperature is 10°C or higher, or difference between set
temperature and room temperature is 15°C or less
4) Current time is between 20:00 and 7:00
Note that the limitation is effective only for 60 minutes after operation
startup.
In heating operation
Indication on main unit Louver correction angle
0°(Present position)
5°Upward
10°Upward
5°Downward
In cooling operation
Indication on main unit Louver correction angle
0°(Present position)
2°Upward
4°Upward
2°Downward
Auto mode
Cooling Heating Dehumidifying
Temperature
setting method
Automatic temperature setting based on outside
air temperature. Can be changed within ±2°C
using remote control.
Manual mode
Cooling Heating Dehumidifying
Temperature
setting method
Can be
changed
between 18
and 32°C
using remote
control.
Can be
changed
between 18
and 32°C
using remote
control.
Automatic set-
ting. Can be
changed within
±2°C.

AYXP26FRN
2 – 11
1.22. Dehumidifying operation control
If the room temperature is 26°C or higher when dehumidifying opera-
tion starts, the dehumidifying operation provides a low cooling effect in
accordance with the room temperature setting automatically deter-
mined based on the outside air operation. (The setting value is the
same as the set temperature for cooling operation in the auto mode.)
If the room temperature is lower than 26°C when dehumidifying opera-
tion starts, the dehumidifying operation minimizes the lowering of the
room temperature.
1.23. SELF CLEAN operation
SELF CLEAN operation will provide efect to reduce the growth mold,
and to dry inside of the air conditioner unit with Plasmacluster ions.
Heating or Fan operation and Cluster operation are performed simulta-
neously.
The judgment of whether Heating or Fan operation is used is based on
the outside air temperature at 3 minutes after the start of internal
cleaning.
The operation stops after 40 minutes. (The air conditioner shows the
remaining minutes: 40 →39 →38 ... 3 →2 →1)
1.24. Plasmacluster Ion function
Operating the Plasmacluster Ion button while the air conditioner is in
operation or in non-operation allows the switching of the operation
mode in the following sequence: "Cleaning operation" →"Ion control
operation" →"Stop".
• "Cleaning operation" generates about equal amounts of (+)ions
and (-)ions from the cluster unit to provide clean air.
• "Ion balance operation" generates more (-)ions than (+)ions from
the cluster unit.
If the Plasmacluster Ion generation function is operated together with
the air conditioner operation, the indoor unit fan speed and louver
direction are in accordance with the air conditioner settings.
If the Plasmacluster Ion generation function is used without operating
the air conditioning function, the indoor unit fan operates at a very low
speed and the upper louver is angled upward and the lower louver
remains horizontal. (The airflow volume and direction can be changed
by using the remote control.)
1.25. Hot keep
When the room temperature rises above the set temperature by 0.6°C
or more, the ON/OFF operation of the compressor and indoor unit fan
is controlled in order to lower the room temperature.
(The values indicated below, such as "0.6°C" and "1.3°C," vary
depending on the outside air temperature.)
1.25.1 Hot keep zone 1
With the compressor frequency at the lowest, if the room temperature
is higher than the set temperature by 0.6°C but no more than 1.3°C,
the following processes will be activated.
1) The compressor stops temporarily, and restarts after 2 minutes.
2) If the room temperature remains in the hot keep zone, the com-
pressor is turned OFF and ON in 3-minute intervals.
3) The indoor unit fan turns OFF and ON with a delay of 30 seconds
from the compressor OFF/ON.
4) After the above operation in 3-minute intervals is repeated four
times, the interval extends to 6 minutes.
1.25.2 Hot keep zone 2
If the compressor ON/OFF in hot keep zone 1 fails to bring the room
temperature within 1.3°C above the set temperature, the following pro-
cesses will be activated.
1) The compressor repeats a cycle of 8-minute OFF and 6-minute
ON.
2) After the second time, the compressor remains completely OFF
and only the indoor unit fan repeats OFF-ON in set intervals.
3) While the compressor is completely OFF in 2), the louvers are set
horizontally to prevent cold air from blowing.
The zone transition and the end of hot keep operation (room tempera-
ture lower than the set temperature) are judged when the compressor
ON period ends.
1.26. Winter cool
The air conditioner cannot be operated in the cooling mode during win-
ter (low outside air temperature) in principle. However, by cutting the
JP-WK (jumper wire) on the outdoor unit control printed circuit board
(control PCB), cooling operation can be operated at a lower outside air
temperature. When the outside air temperature is low, the outdoor unit
fan operates at slower speed.
1.27. Auto restart
When power failure occures, after power is recovered, the unit will
automatically restart in the same setting which were active before the
power failure.
1.27.1 Operating mode (Cool, Heat, Dry)
• Temperature adjustment (within 2?C range) automatic operation°
• Temperature setting
• Fan setting
• Air flow direction
• Power ON/OFF
• Automatic operation mode setting
• Swing louvre
• Plasmacluster mode
1.27.2 Setting not memorized
• Timer setting
• Full power setting
• Internal cleaning
1.27.3 Disabling auto restart function
By removing (cutting) jumper J (JPJ) on the printed circuit board
(PCB), the auto restart function can be disabled.
Heating operation Fan operation
24
O
C
Outside air temperature
1.3OC
0.6OC
Set temperature

AYXP26FRN
2 – 12
2. Explanation of cluster circuit
The cluster unit generates cluster ions, which are circulated throughout the room by the air flow created by the blower fan (indoor unit fan motor) in
the air conditioner unit.
1) When microcomputer output 1 turns "H," the IC6-1 output changes to "Lo," turning ON the SSR and applying 230 V to the cluster unit for the gen-
eration of cluster ions (positive and negative ions).
2) When the SSR is ON, monitor voltage (1 to 3.5 V) is applied to the microcomputer input.
The monitor voltage is lower than 0.1 V or higher than 4.5 V for 30 consecutive minutes, an error is detected and the cluster drive output (SSR)
remains OFF until the operation is shut down.
Note that the above condition will not cause the air conditioner to shut down in an error mode, and the air conditioning operation continues.
3) For a cluster mode change, microcomputer output 2 changes to "H," and this sets the IC6-2 output to "Lo" and turns ON the Q8 (digital transistor).
As a result, the relay inside the cluster unit is applied with 12 V, and the internal relay turns ON.
When the SSR is turned ON in this condition, more negative ions are generated to provide negative-ion-rich air.
• Cluster mode switching is usually performed in the cluster OFF (SSR = OFF) status.
3. Outline of PAM circuit
3.1. PAM (Pulse Amplitude Modulation)
The PAM circuit varies the compressor drive voltage and controls the rotation speed of the compressor.
The IGBT shown in the block diagram charges the energy (electromotive force) generated by the reactor to the electrolytic capacitor for the inverter
by turning ON and OFF.
When the IGBT is ON, an electric current flows to the IGBT via the reactor (L5) and diode bridge (DB2).
When the IGBT turns OFF, the energy stored while the IGBT was ON is charged to the voltage doubler capacitor via the diode bridge (DB1).
8
3
5
2
1
12V
SSR
C23
RE RN NF2 C28
R20
IC6-1
AC230V
Microcomputer output 1
1
5
3
6
7
Cluster unit
R23
R75 R76
PAM drive circuit block diagram
Reactor L5
[PAM drive circuit]
+
Microcomputer (IC1)
AC
230V
Compressor
Reactor L6
Noise
filter
AC clock
detection
circuit
DB1
IPM
DB2
Compressor
position
detector
IGBT
drive
circuit
IGBT
Overvoltage
detection
circuit

AYXP26FRN
2 – 13
As such, by varying the ON/OFF duty of the IGBT, the output voltage is varied.
3.2. High power factor control circuit
This circuit brings the operating current waveform closer to the waveform of commercial power supply voltage to maintain a high power factor.
Because of the capacitor input, when the PAM circuit is OFF, the phase of the current waveform deviates from the voltage waveform as shown below.
To prevent this deviation, a current is supplied during the periods indicated by "O" in the diagram.
To determine the length of period to supply a current, the zero-cross timing of the AC input voltage is input to the microcomputer via the clock circuit.
The power source frequency is also determined at the same time.
The IGBT turns ON after the time length determined by the zero-cross point to supply a current to the IGBT via the reactor.
This brings the current waveform closer to the voltage waveform in phase.
As described above, the ON/OFF operation of the IGBT controls the increase/decrease of the compressor power supply voltage (DC voltage) to
improve the compressor efficiency and maintain a high power factor by keeping the current phase closer to that of the supply voltage.
3.2.1 Detailed explanation of PAM drive circuit sequence
3.2.2 AC clock (zero-cross) judgment
• The clock circuit determines the time from one rising point of the clock waveform to the next rising point.
The detected clock waveform is used to judge the power source frequency.
• The zero-cross of the AC voltage is judged as the rising of the clock waveform, as shown in the diagram above.
Stored energy
Reactor
L5
L6
DB1
DB2
IGBT
IGBT ON
IGBT OFF
AC voltage waveform
AC voltage and current waveform when PAM is ON
AC current waveform
IGBT ON period
Zero-cross detection
AC voltage waveform
AC current waveform
AC voltage and current waveforms when PAM is OFF
AC voltage waveform
Clock
IGBT ON
A
BC
A
B
C
50Hz
1.2mS
300 S
0.5 3.2mS

AYXP26FRN
2 – 14
3.2.3 IGBT ON start time (delay time B)
• Based on the zero-cross of the AC voltage, the IGBT turns ON after a delay time set according to the power source frequency.
3.2.4 IGBT ON time (C)
• After the above delay time, the IGBT turns ON to supply a current to the reactor.
• The ON time of the IGBT determines the amount of energy (level of DC voltage rise) supplied to the reactor.
DC voltage level in each operation mode (varies depending on external load conditions)
– Cooling operation --- 220 to 240 V
– Heating operation --- 220 to 280 V
3.3. PAM protection circuit
To prevent excessive voltage of PAM output from
damaging the IPM and electrolytic capacitor as well
as the control printed circuit board (PCB), this circuit
monitors the PAM output voltage and turns off the
PAM control signal and PAM drive immediately
when an abnormal voltage output is generated. At
the same time, it shuts off the compressor operation.
The PAM output voltage is distributed to pin (4) of
the comparator (IC8). If this voltage exceeds the ref-
erence voltage at pin (5) of the IC8, the output of the
comparator (IC8) reverses (from H to L) and it is
input to pin (38) of the microcomputer (IC1) to halt
the PAM drive.
The protection voltage level is as follows.
– Overvoltage --- 350 V or higher
3.3.1 Details of troubleshooting procedure for PAM
1) PAM shutdown due to error
1) When the DC voltage detection circuit sends a signal exceeding the specified voltage to the microcomputer
DC voltage of 400 V or higher (detection circuit input voltage of about 8.4 V or higher) [IC8 pin (4)]
– When an error is detected
• PAM IGBT turns OFF.
• Compressor turns OFF.
• All units shut down completely when the error occurs four times.
2) When the outdoor unit clock waveform differs from the specified value immediately before the PAM IGBT turns ON
When there is no clock waveform input
When a clock signal of other than specified power source frequency is input
– When an error is detected
• PAM IGBT does not turn ON.
• Compressor operates normally.
• Complete shutdown does not occur.
2) PAM error indication
In case of error "1)"
– An error signal is sent to the indoor unit as soon as an error is generated.
• Malfunction No. 14-0 is indicated when the error code is called out by the indoor unit's self-diagnosis function.
– The LED on the outdoor unit flashes 14 times when an error is generated.
• The LED continues flashing in the 14-time cycle even after the compressor stops operating.
• The LED turns off (data is deleted from the memory) when the outdoor unit power is turned off.
In case of error "2)"
– An error signal is sent to the indoor unit as soon as an error is judged.
• Malfunction No. 14-1 is indicated when the error code is called out by the indoor unit's self-diagnosis function.
– The LED on the outdoor unit flashes 14 times when an error is judged.
• The LED on the outdoor unit flashes in normal pattern when the compressor stops operating.
(Compressor OFF or Thermostat OFF from remote control)
* When a user complains that the air conditioner does not provide sufficient cool air or warm air
R2
255K
C10C9
420V
750uF R5
300K
R7
23.7KF
R6
23.7KF
0V
0V
0V
IC8
15V
R113
19.1KF
R112
15K
5V
R114
1M
R116
1K
5
4
2
(Overvoltage detection)
During abnormal voltage output
IC1
38

AYXP26FRN
2 – 15
In addition to conventional error-generating reasons, there is a possibility that the PAM IGBT does not turn ON even if the compressor is operating.
In that case, the DC voltage does not rise even though the compressor is operating, and lowers to the 180-VDC level.
– Check items
• Clock circuit check
• PAM IGBT check
• Fuse (Fu4) open-circuit check
4. Explanation of IPM drive circuit
The IPM for compressor drive is made by Mitsubishi Electric.
The power supply for the IPM drive, the shunt resistance for overcurrent detection, etc., are provided outside the IPM (control PCB).
4.1. IPM drive power supply circuit
The power supply for the upper-phase IGBT (HU, HV, HW) drive employs a bootstrap system, and provides power to the upper-phase IC.
The 15-V power supply for the lower-phase IC is provided by the control printed circuit board (PCB).
4.1.1 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).
This results in a charging current that flows to the electrolytic capacitor of each upper-phase IC input and charges the bootstrap capacitor with a 15-V
current.
The power supply for the subsequent stages is charged while the lower-phase IGBT is ON in ordinary compressor drive control.
P(Vcc)
U,V,W,
VD
VDB
VCIN(n)
N-side
IGBT
N(GN
D
Bootstrap capacitor
High-voltage-withstanding,
high-speed recovery diode
LVIC
(LU,LV,LW)
HVIC
(HU,HV,HW)
Bootstra
p
circuit
Initial charge period
Charging current group

AYXP26FRN
2 – 16
4.1.2 DC overcurrent detection circuit
When a current of about 25 A or higher flows through the shunt resistance (R49) on the control printed circuit board (PCB), the voltage at this resis-
tance 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 off the overcurrent. At
the same time, an L output of about 1.8 ms is generated from IPM Fo pin (18), and this results in an L input to overcurrent detection input pin (15) of
the microcomputer (IC1) and turns OFF the PWM signal output (IC1 pins (9) through (14)) to the IGBT gate.
SET
RESET
(About 22 A)
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
IPM overcurrent
detection circuit
5V
0V
IC1
R49 Overcurrent
Shunt resistance
P
N
CiN
FO
24
26
36
51 56