AYXP9GHR

AYXP9GHR 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 powerRectification circuit

CPU

SubCPU

3.15AFuse

Serial signals

2AFuse

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

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 andserial signals)

2 – 1

AYXP9GHR

2. Outdoor unit

CPU

20Aprotection

15Aprotection

Expansion valve drive circuit Expansion valve

Suction temp. thermo. circuit Suction pipe thermistor

2-way valve temp. thermo. circuit 2-way valve thermistor

3.15Aprotection

15Aprotection

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 factorconverter circuit

Filtercircuit

Smoothingcircuit

Pulse amplitube modulation circuit

EEPROM

AC clock circuit

DC overcurrent detection circuit

IGBT

Unit-unit wiring (AC powerand serial signals)

Outdoor fan

4-way valve

Power transistor module

Compressor

Current transformer

Compressor thermistor

Heat exchanger pipe thermistor

Outdoor temperature thermistor

LED

2 – 2

AYXP9GHR

[2] MICROCOMPUTER CONTROL SYSTEM

1. Indoor unit

1.1. Electronic control circuit diagram

0.1μC 50

V

JPF

54

21

54

21

4.7KRN

2.4K5V 10.0KFR96

JPT

9 10 11 12

CIR

CU

ITD

IAG

RAM

DIS

PLAY

PWB

LOU

VER

MO

TOR

TOP

LOU

VER

MO

TOR

BOTT

OM

DR

AIN

PAN

ASS'

Y

MO

TOR

FAN

DC

AUX.

SW1

(TES

TR

UN

)

PIPE

THER

MO

TEM

PTH

ERM

O

POW

ERO

N

10K

R52

(HA

CIR

CU

IT)

AUTO

RES

TAR

T

PREH

EAT

WIR

ELES

S

HO

TKE

EP

FLAS

H

TEST

SUB

MIC

RO

CO

MPU

TER

PWB

REC

EIVE

RPW

B7

-SEG

LED

&

REM

OTE

CO

NTR

OLL

ER SIG

NAL

SER

IAL

SIG

NAL

S

OF

SER

IAL

ERR

OR

SIG

NAL

SUB

MIC

RO

CO

MPU

TER

POW

ERSU

PPLY

OF

12V

LIN

EG

ND

for

GN

Dfo

r5V

LIN

E

CO

NN

ECTO

RO

FJO

INT

(DR

AIN

PAN

)

CO

NN

ECTO

RO

FJO

INT

(FAN

MO

TOR

)

33

98

76

101

23

45

8

R4156k

5V

23 1

4 32

R38100k

C1835V100μ

R39

ZD2HZ24-2

41 4.7k

D1N60D7

R37 RD

4

21

30.

1μC42

25V

12V

R44

1.8k

1/4W

C2116V47μ

R70

Q3

KRC

108S

4.7k

4.7k

(SER

IAL

I/OC

IRC

UIT

)

KRA1

01S

Q11

5V

5VJP

H

R53

JPO

10K

ACC

LOC

K

25V

R90

R55

FU1

3.15

A-2

50V

C57

R85

10K

50V

1000

p

C20250V0.01μ

5V

JPS

470μ

D2S

6M

MQ

R27

10K

10k

R71 1k

1k

R336.8k

8.2k

680

PC5

R34

6.8k

89

5V

12V

87654321

86

75

43

21

1 3 5 7 9

2 4 6 8 10

1112

1 3

5VVs

VccPG

GN

DVm

3 12577 5 2 13

3 1257

PC3

BCN

5

BCN

1 PC81

716P

1210

111

23

45

67

89 9

87

65

43

21

1110

1210

111

23

45

67

899

87

65

43

21

1110

7654321

BCN

7

KRC

102S

Q15

PC1

PC81

7XP3

C16

50V

0.01

μ

10K

R16

275V

0.01

μ

C23

2.7K

RH

RE

R76

100

1W

SSR

12V

2W11K

2W11K

PC2

PC85

3HXP

2W680

680 2W

2W680

680 2W

2W680

D8

D1N

60R

GR

40R

BR

CR

A

C14275V0.1μ

NF1

NR1

200K

200K 39

K

D3

D1N

60

1/2WR26

1/2WR25 R24

C45275V0.1μ

E25

0V47

00p

C53

~C56

C54

C53

C56

C55

CN

801

23

4

BUSY

7654321 8

VPP

VCC

SCL

SDA

OE

RES

ET

9VS

S

5V

321

C90

HAJ

P

4

CN

90R

92

R91

100kR93

1000

p50

V

5V

5V

100μ

C350V

R95

4.7K

R69100K

R684.7K

100μ

DC

15V

D2S

BA60

5V

C2425V

0.1μR

46

DB1

C1

3.3

450V120μ

1M

R2 RF1/2W

1M1/2W

4 321

5V

PC81

7XP3

3.3KR66

100KR73

35VC46

25VC50

0.1μ

0.1μ50VC47

R28

R31

56k

2A-2

50V

142

3

14

5V

FU2

5WR1

47kR67

10kR50

0.1μC

5225

VC

37

0.1μ25

V

5V

JPW

JPP

R87

R86

10K

10K

C26

4.7μ

IC2

RES

ET

0V

ZD1

ST03

D-2

00

5V

1/4W

100

R561/4W

100

R51

C39

16V

0.01

μ

C36

0.01

μ16

V

10K

10K

10K

CN

4

R58

R54

R59

10.0KF

16V10μC31

R61

16V10μC30

R60

34TH

1

12TH

2

321

5V

21

4 3

D1F

S4

0.1μ50

VC4

C44

220μ

10V

C7

470μ

10V

25V

C43

12V IC9

10μHL1

D14 D

1

TR1

6 5 4 3 2 1 4

34

12

IC108

765

EEPR

OM

R97

5V

R47

3

3.3k 2

R29

PC4

R32

C17

0.01μ16V

IC1

64636261605958575655545352515049 P37

P36P35P34P33P32P31P30VCC

VRVSSP67P66P65P64P63

P00

P01

P02

P03

P04

P05

P06

P07

P10

P11

P12

P13

P14

P15

P16

P17

3348 47 46 45 44 43 42 41 40 39 38 37 36 35 34

P20P21P22P23P24P25P26P27VSSXOUXINP40P41RSTVSSP42

20212223242526272829303132

191817

P43

P44

P45

P46

P47

P50

P51

P52

P53

P54

P55

P56

P57

P60

P61

P62

161 2 3 4 15141312111098765

R35

10k 5V

R36

C22

PC81

7XP3

R30

16V0.01μ

4.7K

1000

p50

VC

32

5V

KRC

102S

Q19

C2510V

100μ

C27

16V

0.01

μ4.

7kR

45

R94

5V

10k

R48

C331

3

2OSC

1 8MH

z

KRC

108S

Q1

10.0KF

1 N1 3 65

N S

321

5 6

CN

A

3112

V

IN

RY1

(CLU

STER

)C

ON

NEC

TOR

OF

JOIN

TO

UT

N12

R191/2W470K

R19A1/2W470K

3W11

K3W 11K

C98

C99

1KV

1000

pC

98,C

99

KID

6500

4AF

12V

C1950V0.047μ

IC6

BZ

GEN

ERAT

OR

CLU

STER

4.7K

33p

2KV

RM

1500

p

10KF

15V

100p

F

15KF

1.5KR10

1000

0pM

R17

12

680

PC81

7XP3

PC9

4.7K

R4

3.3KR75

910

1/4WR20

1/4WR23

910

R22

R3

R65

R5

ZD5

C12

50VC5

50VC2

100μ

D2

D1F

L20U

D1F

L20U

C35

IC3

1 2

5 34

R7 10

00p

50VC40

10K

D1F

L20UD

15

D21

KRA1

06S

IC7

R57

D20

D1F

L20U

Q9

PC81

7XP3

1KR81

2.4K

FR8

2.4K

FR11

R80

PC6

1KR9

PC817XP3

R6

100K

PC81

7XP3

R13

100K

PJ43

1CT

250VC48

PC6

PC7

R17

1K

R984.7K

R89 1K

100V

1.2K

C49

11KF

30KF

L2KI

A781

5API

1SR

139D

2 – 3

AYXP9GHR

1.2. Display circuit diagram

12V

KID

6500

4AF

M5V

M5V

M5V

M5V

7654321

10 111 2 3 4 5 6 7 8 9

12V

12V

5V

KID

6500

4AF

CN

103

CN

102

IC10

5

IC10

6

CN

101

IC10

4

13

28M

Hz

P30

19P3

120

P32

21P3

322

P34

23P3

524

P36

25P3

726

P00

27P0

128

P02

29P0

330

P04

31P0

532

P06

33P0

734

P10

35P1

136

Vss

18Xo

ut17161 2 3 4 15141312111098765

P12

P13

P14

P20

P21

P22

P23

P24

P25

P26

P27

Vref

RES

ETC

NVs

sVc

cXi

n

IC10

1M

3754

2

OSC

101

0.1μ25

VC

101

C10

2

4.7μ

IC10

2

0.1μ25V

C10

3

C10

416

V47

μ

IC10

3

KID

6578

3AF

R10

1

R10

2

R10

3

R10

4

R10

5

R10

6

R10

71W18

0*7

FLASH

4.7KR115

4.7K

R10

8

R11

810

KR

116

100K

KRA1

06S

KRC

106S

KRA1

06S

R109

R113R110

R114

1/4W

1.2K

*4

LED

LED

LED

LED

LED

LED

LED

LED

LED

LED

LED

101

102

103

104

105

106

107

108

109

110

PC

CN

105A

CN

104B

CN

104A

a b c d e f g

SG20

1

Q10

2Q

101

Q10

4

KRC

106S

Q10

3

CN

105B

CN

105C

1 2 3

25V

R20

147

IC20

1

REC

EIVE

RC

IRC

UIT

SUB

MIC

RO

CO

MPU

TER

PWB

CIR

CU

ITD

AIG

RAM

12345

LOU

VER

MO

TOR

BOTT

OM

LOU

VER

MO

TOR

TOP

SER

IAL

SIG

NAL

S

REM

OTE

CO

NTR

OLL

ERSI

GN

ALS

ERR

OR

SIG

NAL

OF

SER

IAL

POW

ERSU

PPLY

OF

SUB

MIC

RO

CO

MPU

TER

5VLI

NE

GN

Dfo

r

12V

LIN

EG

ND

for

7-S

EGLE

D&

REC

EIVE

RPW

B

GN

Dfo

r12

VLI

NE

GN

Dfo

r5V

LIN

E

12V

LIN

EG

ND

for

12V

LIN

EG

ND

for

GN

Dfo

r12

VLI

NE

12V

LIN

EG

ND

for

JP1

GN

Dfo

r5V

LIN

E

DIS

PLAY

PWB

( )B L U E

SIG

NAL

SR

EMO

TEC

ON

TRO

LLER

GP1

U26

1RK

111B

(COM)5

(COM)10

7(A1)

6(B1)

4(C1)

1(D1)

3(E1)

8(F1)

9(G1)

2(H1)

7(A2)

6(B2)

4(C2)

1(D2)

3(E2)

8(F2)

9(G2)

2(H2)

c d e f g

JP2

0.22

μ50

VC

105

KRC

106S

Q10

5

1K

5V

R11

9

25V

C20

247

μ16

VC

201 0.1μ

+

C2

C1

H2

H1

B2B1

F2F1

E2E1

D2

D1

G2

G1

A2A1

a

b

c

d

e

f

g

g

f

e

d

c

b

a

RES

ET

987654321 12111010 11 121 2 3 4 5 6 7 8 9

10 9 8 7 6 5 4 3 2 1

543211 2 3 4 5

KID

6500

4AF

12V

12V

8

7

6

5

4

3

2

1

9

1 2 3 4 5 6 7 8

12V

5V

2 – 4

AYXP9GHR

1.3. Printed wiring board

2 – 5

AYXP9GHR

2. Outdoor unit

2.1. Electronic control circuit diagram

9.53

KFR84

0V

Q10

0V

15V

0.01

μ

10V

47μ

6.8K

J

R85

C77

R86

C78

2A25

0VFU3

754321

0VC

N30.1μ40

0VC29

0V

5V

R83

10K

RY1

123456

0VIC

7

Ma

b

5V

10K

10K

0V

j

0V

JP1

JP2

c

JPF

0V10

0μ

C94

10V

C95 0.1μ

0.1μ

10K

R37

1K

R38

1K

R36

1K

0VUVW

C34C35C36

1000

Px

3

D7

D6

TR1

R29

4.7K

68

18V

-PC

850.

1μ

R82

680μ

C19

IC3

R27 1W

IC4

5V 0V

R22

25V

C20

R21

22K

R24

10K

R87

150μ

C84

D14

9

35V

0V-P

35V

R93

R94

R92

D20

C98

3

2

1R

78IC

5

C33

R77

50V

1μ

R79

100

0.1μ

C32

0V

QS

T

R

Q3

R S T9

Q

JP10

1 2 3 4 5 6 7 8

8

5 6 11 10

7

1K 10K

9

8

Q9

0V

2.2KR32R31

0V

R33

IC6

875 6

124 3

CN

E

5VR

30

4 3 12

4.7K

13V

CN

12

EXPA

NSI

ON

VALV

CO

IL

MR

Y1

13V

C38

0.1μ

24272322212818161315124 1079613

10K

R45

5V

100μC47

1000

PC

42

C48

10V

0.1μ

0V

IPM

330μ

25V

C37

100μ 25

VC

490.

1μ

25V

C51

0.1μ

C54

100μ 25

VC

530.

1μ

0.1μ

0.1μ

C55

0.1μC

57

C45

0.1μ

C56

D9

D10

100μC52D

8

C50

VWFB

VUFS

VUFB W

NVNUNWP

VPI

VWFSVP

I

VPI VP

VVFS

VVFBU

P

VNC F0VNI

C41

1000

P

1000

PC40

C43

1000

P

C44

1000

PC39

1000

P

1KR46

ZD4

16V

10μ

x5

C70

~74

10K

x5

R63

~67

0V

0VC

N8

1065432 7 980.

01μ

x5

C65

~69

5V

TH2

TH3

TH4

TH5

133

0KR

100

R10

7

PC4

330

Q7 KR

C10

5S

1000

PC

59

1/2W

R51

~53

IPM

c6 58

5WR49

2 3 TLP3

51

j

M

270K

DR

126

255K

F

250V

FU5

0.02

5V

15A

470K

Fx

3

CIN

CF0

262531

35

150

R11

0

250V

FU4

1Aj

1KV

C27

220P

FC

1550

V10

μ

R17

STR

-L47

2IC2

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

2SA1

586G

Q1

ZD1

0V

470P

C17

R14

R18 1.5K

3300

PD

4

OC

P/FB

1~

48

710

96

Sour

ceG

ND

Dra

inVc

c

C18

680

R16

R15

C16

D15

1.6

1.6

3

D3

R19

15V

PC3

234

1

0.01

μC

81

R14

610

0K

e d 5V5V

FU2

R10

5

0V

22K

3.3K

R10

6

C83

1000

P

0.01

μC

82

Q6

KRC

102S

10V

C79

R91

R14

710

K

R90

D2 1.0K

F22

0μ

2.2K

R11

1

DB2

Q5

TER

MIN

ALBO

ARD N 1

WH

WH

GR

R89

0V

BLU

E

BRO

WN

YELL

OW

GR

EEN

/

T2 T1

1 2

L3L4

13

3 4

SA1

NR

1T4

R1

1/2W

1M

275V

1μF

275V

1μF C

2

42

1μF

275V

CT1

T6

510K

1/4W

R88

1/4W

510K

C1

C3

OU

TIN

PTC

MR

Y1G

RG

R

T5

DB1

18V

-P

4700pF250V

4700pF250V

4700pF250V

4700pF250V

R4

3.3K

D1

0.1μC13

1K2W2W 1K

1K2W

4700

P25

0VC

12

+42

0V42

0V+

3.15

A25

0V

R101

R102

R103

R104

1/2W

47K

x2

R10

1,10

2

1W47

Kx

2R

103,

104

T10

T11

PC81

716N

IP

5V

0VR

55

R56

R54

C60

0.1μ25

V

R99

100

0.1μC86

15K

R11

2

C61

50V

330P

330P

50V

C62

R57

100

R58

100

R59

100

C63

330P

50V

12

678910

0.1μC64

25V

114

35

IC8

KIA3

39

1

5V0V

0.01

μC

97

UV

NW5V

0VC88

1000

P

N1KR11

6

RY1

120

1/2W

0.03

3μ

NR

2

275V

CN

4

C26

R28

3 1de

D24

2R

EDT3

R12

910

K

T12 T13

250V 20A

FU1

R34

R35

JP16

5V

5V

0.1μC93

100μ10V

C30

5V

0V

JP9

JP8

JP7

32313029282726252423222120

1011

1213

1415

1617

1819

12

34

56

89

7

52535455565758596061626364

5150

4948

4746

4544

4342

4140

3938

3736

3534

33

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

MD

1

MD

2

X1X0 VSS

P00

P01

P02

P03

P04

P05

P06

P31

P32

P33

P34

P35

VCC

CP36

P37

P40

P41

P42

P43

(X)

(V)

(Y)

(W)

(Z)

(U)

(V)

(W)

R13

310

0

R13

210

0

R13

710

0

R13

610

0

R13

510

0R

134

100

5V

5V

2.2K

R73

LED

1

10K

R15

510

KR

154

5V

(CN

)

41 2 3O

SC1

4MH

z

0V10

K10

K

20

JP17

N35

VNO

20.5

KF

20.5

KF

20.5

KF

0V

PS21

563

or21

564

FU6

250V

15A

1000

PC

46

0V

0V

C4A

C5A

C7A

C6A

R41

R42

R43

102W

2K

680P

6.8K

6.8K

270

270

15V

D11

6.8K

Fx

5R

68~

72

R47

,48

33x

21/

4W

1/4W

33x

2R

47A,

48A

5V

C (R)

S

(C)

R

FC3

FC4

YELL

OW

GR

EEN

/EA

RTH

U32

V33

W34

T7 T8 T9

N

FC1

FC2

FB

D12

D13

R611.8K

R601.8K

R621.8K

1.8KR115

R11

41M

14132

0V-P

D23

D22

D21

15V

0V0.

022μ

C58

ZD3

R50

1.8K

F

VALV

CO

IL

4-W

AY

PC1

PC81

7XP3

3 1

2.7K

R75

b

R74

a

1000

PC

75 0V

4.7K5V

R76

56K

41 2 4 3

2

PC85

3HXP

PC2

4.64

KFR26

R23

68K

C21

0.03

3μ

1.65

KFR25

1.5K

150μ

10K

10K

C23

0.1μ

7805

R81

10K

R14

4

C76

1000

P

5VQ

4

23.7

KF

23.7

KFR6

R7

R12

813

KFR

127

13KF

P0.

33μ

C14

630V

270K

D1/

2W

R12

51/

2WR

21/

2W 300K

F1/

2WR

5

750μ

C10

C9

750μ

(TH

ERM

ISTO

RC

IRC

UIT

)(T

HER

MIS

TOR

)

(SER

IAL

I/OC

IRC

UIT

)

(PAM

OVE

RC

UR

REN

TC

IRC

UIT

)

(EEP

RO

MC

IRC

UIT

)

(4-W

AYVA

LVE

CIR

CU

IT)

(FAN

MO

TOR

CIR

CU

IT)

(FAN

MO

TOR

)

(RES

ETC

IRC

UIT

)(S

WIT

CH

ING

POW

ERSU

PPLY

CIR

CU

IT)

KID

6500

4AP

PST9

93D

KRA1

06S

KRC

105S

KRC

105S

KRA1

06S

(DC

OVE

RC

UR

REN

TC

HEC

KC

IRC

UIT

)

MO

NIT

OR

(FO

RD

EBU

G)

CN

D

(FR

ASH

WR

ITER

CO

NN

ECTO

R)

(LED

CIR

CU

IT)

DET

ECT

CIR

CU

IT)

(RO

TOR

POSI

TIO

N

+

C4

C5

C7

C6

2.7k

F

6.8K

F

13V

0.1μC31

C

19.1

KFR

113

2 – 6

AYXP9GHR

2.2. Printed wiring board

2 – 7

AYXP9GHR

[3] FUNCTION

1. Function

1.1. Startup controlThe main relay remains off during the first 45 seconds (first safetytime) immediately after the power cord is plugged into an AC outlet inorder to disable outdoor unit operation and protect outdoor unit electriccomponents.

1.2. Restart controlOnce 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 remotecontrol and then turned back on immediately after, the compressor willrestart after a preset delay time.

(The indoor unit will restart operation immediately after the ON switchis operated on the remote control.)

1.3. Cold air prevention controlWhen the air conditioner starts up in heating mode, the indoor unit fanwill not operate until the temperature of the indoor unit heat exchangerreaches about 23°C in order to prevent cold air from blowing into theroom.

Also, the indoor unit fan operates at low speed until the temperature ofthe indoor unit heat exchanger reaches about 38°C so that people inthe room will not feel chilly air flow.

1.4. Odor prevention controlWhen the air conditioner starts up in cooling mode, the discharged airtemperature is lowered slightly, and for the reduction of unpleasantodors the operation of the indoor unit fan is delayed 60 seconds if theautomatic fan speed mode in cooling mode is set.

1.5. Indoor unit heat exchanger freeze prevention controlIf the temperature of the indoor unit heat exchanger remains below0°C for 4 consecutive minutes during cooling or dehumidifying opera-tion, the compressor operation stops temporarily in order to preventfreezing.

When the temperature of the indoor unit heat exchanger rises to 2°Cor higher after about 180 seconds, the compressor restarts andresumes normal operation.

1.6. Outdoor unit 2-way valve freeze prevention controlIf the temperature of the outdoor unit 2-way valve remains below 0°Cfor 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 afterabout 180 seconds, the compressor restarts and resumes normaloperation.

1.7. Indoor unit overheat prevention controlDuring heating operation, if the temperature of the indoor unit heatexchanger 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 isdecreased by about 4 to 15 Hz. Then, this operation is repeated every60 seconds until the temperature of the indoor unit heat exchangerdrops below the overheat protection temperature.

Once the temperature of the indoor unit heat exchanger drops belowthe overheat protection temperature, the operating frequency isincreased 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 about180 seconds, and the abovementioned control is repeated.

1.8. Outdoor unit overheat prevention controlDuring cooling operation, if the temperature of the outdoor unit heatexchanger exceeds the outdoor unit heat exchanger overheat preven-tion temperature (about 55°C), the operating frequency is decreasedby about 4 to 15 Hz. Then, this operation is repeated every 60 sec-onds until the temperature of the outdoor unit heat exchanger drops toabout 54°C or lower.

Once the temperature of the outdoor unit heat exchanger drops toabout 54°C or lower, the operating frequency is increased by about 4to 10 Hz every 60 seconds until the normal operation conditionresumes.

If the temperature of the outdoor unit heat exchanger exceeds the out-door unit heat exchanger overheat protection temperature for (120 sec: outdoor temperature ≥ 40°C • 60 sec : outdoor temperature < 40°C)at minimum operating frequency, the compressor stops operating andthen restarts after about 180 seconds, and the abovementioned con-trol is repeated.

1.9. Compressor overheat prevention controlIf the temperature of the compressor exceeds the compressor over-heat prevention temperature (110°C), the operation frequency isdecreased by about 4 to 10 Hz. Then, this operation is repeated every60 seconds until the temperature of the compressor drops below theoverheat protection temperature (100°C).

Once the temperature of the compressor drops below the overheatprotection temperature, the operating frequency is increased by about4 to 10 Hz every 60 seconds until the normal operation conditionresumes.

If the temperature of the compressor exceeds the overheat protectiontemperature (for 120 seconds in cooling operation or 60 seconds inheating operation) at minimum operating frequency, the compressorstops operating and then restarts after about 180 seconds, and theabovementioned control is repeated.

Compressor operation

ON operation onremote control

OFF operation onremote control

Compressor ON

Compressor ON Compressor canturn ONCompressor remains OFF

for 180 seconds

Indoor unit heat exchanger temperature

38

23

35

21

Set fan speed

Indoor unit fan at low speed

Indoor unit fan in non-operation

2 – 8

AYXP9GHR

1.10. Startup controlWhen the air conditioner starts in the cooling or heating mode, if theroom temperature is 2°C higher than the set temperature (in coolingoperation) or 3.5°C lower (in heating operation), the air conditioneroperates with the operating frequency at maximum. Then, when theset temperature is reached, the air conditioner operates at the operat-ing frequency determined by fuzzy logic calculation, then enters thenormal control mode after a while.

1.11. Peak controlIf the current flowing in the air conditioner exceeds the peak controlcurrent (see the table below), the operation frequency is decreaseduntil the current value drops below the peak control current regardlessof the frequency control demand issued from the indoor unit based onthe room temperature.

1.12. Outdoor unit fan delay controlThe compressor stops immediately after cooling, dehumidifying orheating operation is shut down, but the outdoor unit fan continuesoperation for 50 seconds before it stops.

1.13. Defrosting

1.13.1 Reverse defrostingThe defrost operation starts when the compressor operating timeexceeds 20 minutes during heating operation, as shown below, andthe 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 13C or higher orthe defrosting time exceeds 10 minutes.

1.14. ON timerThe ON timer can be activated by pressing the ON timer button. Whenthe ON timer is activated, the operation start time is adjusted based onfuzzy logic calculations 1 hour before the set time so that the roomtemperature reaches the set temperature at the set time.

1.15. OFF timerThe 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 forquieter operation, and the room temperature is gradually varied afterone hour (reduced 1°C three times (max. 3°C) in heating, or increased0.3°C three times (max. 1°C) in cooling or dehumidifying operation) sothat the room temperature remains suitable for comfortable sleeping.

1.16. Power ON startIf a jumper cable is inserted in the location marked with HAJP on theindoor unit control printed circuit board (control PCB), connecting thepower cord to an AC outlet starts the air conditioner in either cooling orheating 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 unit1) 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, holdingdown AUX button for more than 5 seconds activates the malfunc-tion 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 continuesoperating without a malfunction code display, and the main relayturns off after 30 seconds if the short-circuit condition remains.

The malfunction information is stored in memory, and can berecalled 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 AUX button formore than 5 seconds.

3) The content of self-diagnosis (malfunction mode) is indicated by aflashing number.

(For details, refer to the troubleshooting section.)

1.17.2 Outdoor unitIf a malfunction occurs, LED1 on the outdoor unit flashes in 0.2-sec-ond intervals as shown below.

Model Peak control currentCooling operation Heating operation

AY-XP9GHR Approx. 3.8 A Approx. 6.4 AAY-XP12GHR Approx 6.4 A Approx. 7.5 A

20 min or more 20 min or more 20 min or more

DefrostingMax. 10 min

DefrostingMax. 10 min

Start ofheatingoperation

Heating operationSet temperature

Activation ofOFF timer

1 hourlater

Max.1.5 hourslater

Max.2 hourslater

Timer settingreached

1 hourlater

Max.1.5 hourslater

Max.2 hourslater

Timer settingreached

Activation ofOFF timer

Set temperature

-1O

C

-1O

C

-1O

C

0.3O

C0.3

O

C0.3

O

CCooling/dehumidifying operation

1 sec 1 sec 0.6 sec

ON

OFF

(Example) Compressor high temperature abnormality

2 – 9

AYXP9GHR

1.18. Information about auto modeIn 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 temperaturesettings will automatically slide as shown in the chart.

1.19. Airflow controlThe airflow control holds the two upper and lower louvers at specialpositions during operation to prevent discharged air from directly blow-ing onto people in the room.

1.19.1 Cooling/dehumidifying operationWhen the airflow button is pressed the upper louver is set at anupward angle to send the air along the ceiling.

1.19.2 HeatingWhen the airflow button is pressed the lower louver is set at a down-ward angle to send the air directly toward the floor.

1.20. Difference of operation in Auto and Manual modesIn the Auto mode, the temperature setting is automatically determined based on the outside air temperature. In addition, the air conditioner operationdiffers from the operation in the Manual mode as explained below.

1.20.1 Difference relating to set temperature

1.21. Dehumidifying operation controlIf the room temperature is 26°C or higher when dehumidifying opera-tion starts, the dehumidifying operation provides a low cooling effect inaccordance with the room temperature setting automatically deter-mined based on the outside air operation. (The setting value is thesame 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 theroom temperature.

1.22. Self Clean operationHeating or Fan operation and Cluster operation are performed simulta-neously.

The judgment of whether Heating or Fan operation is used is based onthe outside air temperature at 3 minutes after the start of internalcleaning.

The operation stops after 40 minutes. (The air conditioner shows theremaining minutes: 40 → 39 → 38 ... 3 → 2 → 1)

1.23. Plasmacluster Ion functionOperating the Plasmacluster Ion button while the air conditioner is inoperation or in non-operation allows the switching of the operationmode in the following sequence: “Air Clean operation” → “Stop”.

• “Self Clean operation” generates about equal amounts of (+)ionsand (-)ions from the cluster unit to provide clean air.

If the Plasmacluster Ion generation function is operated together withthe air conditioner operation, the indoor unit fan speed and louverdirection are in accordance with the air conditioner settings.

If the Plasmacluster Ion generation function is used without operatingthe air conditioning function, the indoor unit fan operates at a very lowspeed and the upper louver is angled upward and the lower louverremains horizontal. (The airflow volume and direction can be changedby using the remote control.)

1.24. Hot keepWhen the room temperature rises above the set temperature by 0.6°Cor more, the ON/OFF operation of the compressor and indoor unit fanis controlled in order to lower the room temperature.

(The values indicated below, such as "0.6°C" and "1.3°C," varydepending on the outside air temperature.)

1.24.1 Hot keep zone 1With the compressor frequency at the lowest, if the room temperatureis 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 secondsfrom the compressor OFF/ON.

4) After the above operation in 3-minute intervals is repeated fourtimes, the interval extends to 6 minutes.

1.24.2 Hot keep zone 2If the compressor ON/OFF in hot keep zone 1 fails to bring the roomtemperature 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-minuteON.

2) After the second time, the compressor remains completely OFFand only the indoor unit fan repeats OFF-ON in set intervals.

3) While the compressor is completely OFF in 2), the louvers are sethorizontally 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 compressorON period ends.

* This function cannot be repealed.

Modes and Temperature Settings

the figures in ( ) are temperature settings

Auto mode Manual modeCooling Heating Dehumidifying Cooling Heating Dehumidifying

Temperature setting method

Automatic temperature setting based on outside air tem-perature. Can be changed within ±2°C using remote con-trol.

Can be changed between 18 and 32°C using remote control.

Can be changed between 18 and 32°C using remote control.

Automatic setting. Can be changed within ±2°C.

Heating operation Fan operation

24OC Outside air temperature

1.3OC

0.6OC

Set temperature

2 – 10

AYXP9GHR

1.25. Winter coolCooling operation is available during the winter season by the built inwinter cool function.

Lower limit of outdoor temperature range is -10°C DB.

When the outside air temperature is low, the outdoor unit fan operatesat slower speed.

NOTE: Built-in protect device may work when outdoor temperaturefalls below 21°C DB., depending on conditions.

1.26. Auto restartWhen power failure occures, after power is recovered, the unit willautomatically restart in the same setting which were active before thepower failure.

1.26.1 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

1.26.2 Setting not memorized• Timer setting

• Full power setting

• Internal cleaning

1.26.3 Disabling auto restart functionBy removing (cutting) jumper J (JPJ) on the printed circuit board(PCB), the auto restart function can be disabled.

2. Explanation of cluster circuitThe cluster unit generates cluster ions, which are circulated throughout the room by the air flow created by the blower fan (indoor unit fan motor) inthe air conditioner unit.

1) When microcomputer output turns "H," the IC6 output changes to "Lo," turning ON the SSR and applying 230 V to the cluster unit for the genera-tion of cluster ions (positive and negative ions).

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 inverterby turning ON and OFF.

1

3

12V

SSRC23RE RH

R20

IC6AC230VMicrocomputer output

1

5

3

6

Cluster unitR23R75 R76

PAM drive circuit block diagram

Reactor L5

[PAM drive circuit]

+

Microcomputer (IC1)

AC230V CompressorReactor L6

Noisefilter

AC clockdetection

circuit

DB1

IPM

DB2

Compressorpositiondetector

IGBTdrivecircuit

IGBT

Overvoltagedetection

circuit

2 – 11

AYXP9GHR

When the IGBT is ON, an electric current flows to the IGBT via the reactor (L5), (L6) 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).

As such, by varying the ON/OFF duty of the IGBT, the output voltage is varied.

3.2. High power factor control circuitThis 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) toimprove 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 (50Hz).

• The zero-cross of the AC voltage is judged as the rising of the clock waveform, as shown in the diagram above.

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

Stored energyReactor

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

B C

A

B

C

50Hz

1.2mS

0.85mS

0.25 2.1mS

2 – 12

AYXP9GHR

3.3. PAM protection circuit

To prevent excessive voltage of PAM output fromdamaging the IPM and electrolytic capacitor as wellas the control printed circuit board (PCB), this circuitmonitors the PAM output voltage and turns off thePAM control signal and PAM drive immediatelywhen an abnormal voltage output is generated. Atthe same time, it shuts off the compressor operation.

The PAM output voltage is distributed to pin (4) ofthe comparator (IC8). If this voltage exceeds the ref-erence voltage at pin (5) of the IC8, the output of thecomparator (IC8) reverses (from H to L) and it isinput to pin (38) of the microcomputer (IC1) to haltthe PAM drive.

The protection voltage level is as follows.

3.3.1 Details of troubleshooting procedure for PAM1) PAM shutdown due to error1) When the DC voltage detection circuit sends a signal exceeding the specified voltage to the microcomputer

DC voltage of 350 V or higher (detection circuit input voltage of about 9.2 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 (50/60 Hz) is input

– When an error is detected

• PAM IGBT does not turn ON.

• Compressor operates normally.

• Complete shutdown does not occur.

2) PAM error indicationIn 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

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 (Fu6) open-circuit check

R2255KC10C9420V

750uF R5300K

R723.7K

R823.7K

0V0V

0V

IC8

15V

R11319.1KF

R11215K

5VR1141M

R1151.8K R116

1K5

42

(Overvoltage detection)

During abnormal voltage output

IC138

2 – 13

AYXP9GHR

4. Explanation of IPM drive circuitThe 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 circuitThe 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-Vcurrent.

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-sideIGBT

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

2 – 14

AYXP9GHR

4.1.2 DC overcurrent detection circuitWhen 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 (26). Then, the gate voltage of the lower-phase IGBT (LU, LV, LW) inside the IPM turns OFF to cut off the overcurrent. Atthe same time, an L output of about 1.8 ms is generated from IPM Fo pin (24), and this results in an L input to overcurrent detection input pin (34) ofthe microcomputer (IC1) and turns OFF the PWM signal output (IC1 pins (51) through (56)) to the IGBT gate.

SETRESET

(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 relativeto shunt resistance

Error output Fo

(Lower phase)Internal IGBT gate

IPM overcurrentdetection circuit

5V

0V

IC1

R49Overcurrent

Shunt resistance

P

N

CiN

FO

24

26

34

2 – 15

AYXP9GHR

5. 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 waveform, and a position detection signal isgenerated as a reference voltage equaling 1/2 of 280 VDC. However, since there is no induced voltage waveform when the PWM waveform is OFF,the microcomputer performs internal processing so that detection is enabled only when it is ON. Based on the detected position signal, actual PWMwaveform output timing is determined. Since it does not use a filter circuit, the detection accuracy is high.

The microcomputer performs internal processing to cancel spike voltage during the regenerative process.

Furthermore, even if the induced voltage is low, position detection is still possible, thus allowing sensor-less operation at low rotation speed in the ini-tial stage of operation. This reduces the starting current and improves the IPM reliability.

Comparator output waveform(Position signal waveform)

Terminal voltage waveform

Reference voltage(1/2 of DC voltage)

Spike voltage(cancelled)

2 – 16