Hitachi RAM-40QH5, RAM-35QH5 Service Manual

RAM-40QH5

NO. 0270E

SPECIFICATIONS AND PARTS ARE SUBJECT TO CHANGE FOR IMPROVEMENT

ROOM AIR CONDITIONER

OUTDOOR UNIT

AUGUST 2005

Refrigeration & Air-Conditioning Division

SERVICE MANUAL

PM

REFER TO THE FOUNDATION MANUAL

TECHNICAL INFORMATION

FOR SERVICE PERSONNEL ONLY

CONTENTS

SPECIFICATIONS ------------------------------------------------------------------- 5

INSTALLATION ----------------------------------------------------------------------- 8

CONSTRUCTION AND DIMENSIONAL DIAGRAM --------------------- 12

MAIN PARTS COMPONENT --------------------------------------------------- 13

CAPACITY DIAGRAM ------------------------------------------------------------ 15

WIRING DIAGRAM ---------------------------------------------------------------- 20

CIRCUIT DIAGRAM --------------------------------------------------------------- 21

BLOCK DIAGRAM ----------------------------------------------------------------- 25

BASIC MODE ----------------------------------------------------------------------- 27

REFRIGERATING CYCLE DIAGRAM --------------------------------------- 40

DESCRIPTION OF MAIN CIRCUIT OPERATION ----------------------- 42

TROUBLE SHOOTING ----------------------------------------------------------- 66

PARTS LIST AND DIAGRAM -------------------------------------------------- 82

RAM-40QH5

After installation

750

570

280

40

(W)

(A)

COOLING CAPACITY

DC INVERTER DUAL SYSTEM MULTI

TYPE

MODEL

POWER SOURCE

TOTAL INPUT

TOTAL AMPERES

SPECIFICATIONS

OUTDOOR UNIT

RAM-40QH5

HEATING CAPACITY

DIMENSIONS (mm)

NET WEIGHT

1ø, 220 - 240V, 50Hz

W

H

D

(kg)

(kW)

(B.T.U.)

REFER TO THE SPECIFICATIONS PAGE

– 1 –

SAFETY DURING REPAIR WORK

1. In order to disassemble and repair
the unit in question, be sure to
disconnect the power cord plug
from the power outlet before starting
the work.

2. If it is necessary to replace any parts, they should be replaced with respective genuine parts for the unit, and
the replacement must be effected in correct manner according to the instructions in the Service Manual of
the unit.

If the contacts of electrical parts
are defective, replace the
electrical parts without trying to
repair them.

3. After completion of repairs, the initial state
should be restored.

4. Lead wires should be connected and laid as
in the initial state.

5. Modification of the unit by user himself should
absolutely be prohibited.

6. Tools and measuring instruments for use in repairs or inspection should be accurately calibrated in advance.

7. In installing the unit having been repaired, be careful to prevent the occurence of any accident such as
electrical shock, leak of current, or bodily injury due to the drop of any part.

8. To check the insulation of the unit, measure the insulation resistance between the power cord plug and
grounding terminal of the unit. The insulation resistance should be 1M

or more as measured by a 500V

DC megger.

9. The initial location of installation such as window, floor or the other should be checked for being and safe
enough to support the repaired unit again.
If it is found not so strong and safe, the unit should be installed at the initial location reinforced or at a new
location.

10. Any inflammable thing should never
be placed about the location of
installation.

11. Check the grounding to see whether
it is proper or not, and if it is found
improper, connect the grounding
terminal to the earth.

DANGER

First, I must disconnect
the power cord plug

from the power outlet.

– 2 –

WORKING STANDARDS FOR PREVENTING BREAKAGE OF SEMICONDUCTORS

1. Scope
The standards provide for items to be generally observed in carrying and handling semiconductors in relative
manufacturers during maintenance and handling thereof. (They apply the same to handling of abnormal goods
such as rejected goods being returned).

2. Object parts

(1) Micro computer
(2) Integrated circuits (IC)
(3) Field-effect transistors (FET)
(4) P.C. boards or the like on which the parts mentioned in (1) and (2) of this paragraph are equipped.

3. Items to be observed in handling

(1) Use a conductive container for carrying and storing of parts. (Even rejected goods should be handled in

the same way).

Fig. 1. Conductive Container

(2) When any part is handled uncovered (in counting, packing and the like), the handling person must always

use himself as a body earth. (Make yourself a body earth by passing one M ohm earth resistance through
a ring or bracelet).

(3) Be careful not to touch the parts with your clothing when you hold a part even if a body earth is being

taken.

(4) Be sure to place a part on a metal plate with grounding.

(5) Be careful not to fail to turn off power when you repair the printed circuit board. At the same time, try

to repair the printed circuit board on a grounded metal plate.

1M

Fig. 2. Body Earth

Body earth
(Elimik conductive band)

Clip for connection with a
grounding wire

IC

A conductive polyvinyl bag

IC

Conductive sponge

– 3 –

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

Bare copper wire (for body earth)

Working
table

Resistor of 1 M (1/2W)

Earth wire

Fig. 3. Grounding of the working table

2

Screw stop at the screwed
part using a rag plate

Soldering iron

Grounding
wire

Fig. 4. Grounding a soldering iron

Use a high insulation mode (100V, 10M or higher) when ordinary iron is to be used.

(7) In checking circuits for maintenance, inspection or some others, be careful not to have the test probes of the

measuring instrument shortcircuit a load circuit or the like.

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

Staple

– 4 –

1. In quiet operation or stopping the running, slight flowing noise of refrigerant in the refrigerating cycle is

heard occasionally, but this noise is not abnormal for the operation.

2. When it thunders near by, it is recommend to stop the operation and to disconnect the power cord plug

from the power outlet for safety.

3. The room air conditioner does not start automatically after recovery of the electric power failure for

preventing fuse blowing. Re-press START/STOP button after 3 minutes from when unit stopped.

4. If the room air conditioner is stopped by adjusting thermostat, or missoperation, and re-start in a moment,

there is occasion that the cooling and heating operation does not start for 3 minutes, it is not abnormal
and this is the result of the operation of IC delay circuit. This IC delay circuit ensures that there is no
danger of blowing fuse or damaging parts even if operation is restarted accidentally.

5. This room air conditioner should not be used at the cooling operation when the outside temperature is

below –10°C (14°F).

6. This room air conditioner (the reverse cycle) should not be used when the outside temperature is below

–15°C (5°F).
If the reverse cycle is used under this condition, the outside heat exchanger is frosted and efficiency falls.

7. When the outside heat exchanger is frosted, the frost is melted by operating the hot gas system, it is not

trouble that at this time fan stops and the vapour may rise from the outside heat exchanger.

!

CAUTION

– 5 –

SPECIFICATIONS

MODEL

FAN MOTOR

FAN MOTOR CAPACITOR

FAN MOTOR PROTECTOR

COMPRESSOR

COMPRESSOR MOTOR CAPACITOR

OVERLOAD PROTECTOR

OVERHEAT PROTECTOR

FUSE (for MICROPROCESSOR)

POWER RELAY

POWER SWITCH

TEMPORARY SWITCH

SERVICE SWITCH

TRANSFORMER

VARISTOR

NOISE SUPPRESSOR

THERMOSTAT

REMOTE CONTROL SWITCH (LIQUID CRYSTAL)

40 W

NO

NO

NO

YES

YES

5.0A

G4A

NO

NO

YES

NO

450NR

YES

YES(IC)

NO

1600g

WITHOUT REFRIGERANT BECAUSE

COUPLING IS FLARE TYPE.

UNIT

PIPES

REFRIGERANT CHARGING
VOLUME
(Refrigerant 410A)

RAM-40QH5

JU1013D2

MAX. 35m

RAM-40QH5
Additional charge of refrigerant is not required.

– 6 –

SPECIFICATIONS FOR INDOOR UNITS COMBINATION

OPERATION SCOPE

TYPE

DC INVERTER DUAL SYSTEM MULTI COOLING AND HEATING

MODEL OUTDOOR UNIT

PHASE/VOLTAGE/FREQUENCY

CIRCUIT AMPERES TO CONNECT (A)

COOLING

(TWO UNITS)

CAPACITY (kW)

(B.T.U./h)

TOTAL INPUT (W)

EER (B.T.U./hW)

TOTAL AMPERES (A)

POWER FACTOR (%)

HEATING

(TWO UNITS)

CAPACITY (kW)

(B.T.U./h)

TOTAL INPUT (W)

EER (B.T.U./hW)

TOTAL AMPERES (A)

POWER FACTOR (%)

MAXIMUM LENGTH OF PIPING

STANDARD

RAM-40QH5

1ø, 220 - 240V, 50Hz

16

4.0 (1.50 - 4.50)

13,660 (5,120 - 15,360)

1,245 (200 - 1,800)

10.97

5.72 - 5.24

99

5.0 (1.50 - 5.60)

17,070 (5,120 - 19,120)

1,350 (200 - 1,780)

12.64

6.20 - 5.68

99

MAX. 35m (TWO UNIT TOTAL)

CE (EMC&LVD)

RAM-40QH5

MODEL

W

PACKING

(mm)

H

D

cu.ft.

905

633

394

8.27

43

GROSS WEIGHT (kg)

6.35D/9.52DX2

FLARE NUT SIZE (SMALL/LARGE)

INDOOR SUCTION

TEMPERATURE (˚C)

COOLING OPERATION SCOPE

OUTDOOR SUCTION

TEMPERATURE (˚C)

INDOOR SUCTION

HUMIDITY (%)

DEHUMIDIFYING

OPERATION

HEATING OPERATION

SCOPE

16 - 32 22 - 41 BELOW 80

16 - 32 22 - 42 BELOW 80

BELOW 27 –15 - 23 —

– 7 –

DUAL SYSTEM MULTI R.A.C.

RAM-40QH5

COOL / HEAT CAPACITY SPEC. FOR INDOOR UNITS
COMBINATIONS TO BE ABLE TO OPERATE SIMULTANEOUSLY

Whichever indoor units are installed, cooling and heating capacity depends on how many and which indoor units
are operating at that time.

RATING CONDITON (DRY BLUB / WET BULB)

COOLING

HEATING

INDOOR OUTDOOR

27 / 19 ˚C

20 / –˚C

35 / –˚C

7 / 6˚C

POSSIBLE

COMBINATIONS

TO OPERATE

CAPACITY RATING

(kW)

(RANGE)

POWER

CONSUMPTION

(W)

AMPERE (A)

at 230V

OUTDOOR UNIT

C O O L I N G

CAPACITY RATING

(kW)

(RANGE)

POWER

CONSUMPTION

(W)

AMPERE (A)

at 230V

OUTDOOR UNIT

H E A T I N G

ONE UNIT

TWO UNIT

1.8

2.5

3.5

1.8+1.8

1.8+2.5

2.5+2.5

1.8+3.5

2.5+3.5

1.8

(1.00-2.50)

2.5

(1.00-3.10)

3.5

(1.00-4.00)

1.8+1.8

(1.50-4.00)

1.70+2.30

(1.50-4.50)

2.00+2.00

(1.50-4.50)

1.60+2.40

(1.50-4.50)

1.80+2.20

(1.50-4.50)

560

(200-750)

750

(200-880)

1090

(200-1300)

1190

(200-1680)

1245

(200-1720)

1245

(200-1800)

1245

(200-1800)

1245

(200-1800)

2.5

3.3

4.8

5.2

5.5

5.5

5.5

5.5

2.5

(1.10-3.20)

3.4

(1.10-4.40)

4.2

(1.10-5.0)

2.25+2.25

(1.50-5.20)

2.20+2.60

(1.50-5.40)

2.50+2.50

(1.50-5.60)

1.70+3.30

(1.50-5.60)

2.00+3.00

(1.50-5.60)

690

(200-970)

870

(200-1120)

1080

(200-1300)

1100

(200-1480)

1240

(200-1750)

1350

(200-1780)

1350

(200-1780)

1350

(200-1780)

3.0

3.8

4.7

4.8

5.4

5.9

5.9

5.9

ONE UNIT : The values indicated are only for one unit operation when two indoor units are connected.

TOTAL

1.8

2.5

3.5

3.6

4

4

4

4

TOTAL

2.5

3.4

4.2

4.5

4.8

5

5

5

– 8 –

– 9 –

MODEL: RAM-40QH5

– 10 –

– 11 –

AC 220V~240V ONLY

LN

INDOOR 1

C1

D1

C2 D2

INDOOR 2

– 12 –

– 13 –

MAIN PARTS COMPONENT

FAN MOTOR

Fan Motor Specifications

CONNECTION

MODEL

POWER SOURCE

OUTPUT

BLU : BLUE YEL : YELLOW BRN : BROWN WHT : WHITE

GRY : GRAY ORN : ORANGE GRN : GREEN RED : RED

BLK : BLACK PNK : PINK VIO : VIOLET

RAM-40QH5

DC : 360V

40W

RESISTANCE VALUE

( )

20˚C

(68˚F)

75˚C

(167˚F)

—

—

M

RED

BLK

WHT

YEL

BLU

(Control circuit built in)

360V

15V

0V

0-6V

0-15V

– 14 –

MODEL

COMPRESSOR MODEL

PHASE

RATED VOLTAGE

RATED FREQUENCY

POLE NUMBER

COMPRESSOR

Compressor Motor Specifications

CONNECTION

25°C

(68°F)

75°C

(167°F)

(

)

RESISTANCE VALUE

2M = 1.063

2M = 1.268

RAM-40QH5

JU1013D2

SINGLE

DC: 280-330V

50Hz

4

(U)

(V)

(W)

M

M

M

WHITE

YELLOW

RED

WHITE

RED

YELLOW

– 15 –

CAPACITY DIAGRAM (RELATED TO THE AMBIENT TEMPERATURE)

MODEL : RAM-40QH5

7

6

5

3.8

4.01

4.12

RATING
CAPACITY

COOLING CAPACITY (KW)

INPUT (W)

4.00

3.72

735

1050

1208

1245

1332

4

3

2

1

0

20 25 30 35

40 45

0

1000

2000

3000

COOLING CAPACITY (ROOM TEMPERATURE 27°C)

WHEN TWO INDOOR UNITS OPERATE

– 16 –

CAPACITY DIAGRAM (RELATED TO THE AMBIENT TEMPERATURE)

MODEL : RAM-40QH5

HEATING CAPACITY (ROOM TEMPERATURE 20°C)

WHEN TWO INDOOR UNITS OPERATE

– 17 –

CAPACITY DIAGRAM (RELATED TO THE PIPING LENGTH)

MODEL : RAM-40QH5

1. 0

0. 9

0. 8

0. 7

0. 6
0 5 10 20 3025 3515

PIPING LENGTH (m)

CHANGE RATIO OF

CAPACITY

HEATING

1. 0

0. 9

0. 8

0. 7

0. 6
0 5 10 20 3025 3515

PIPING LENGTH (m)

CHANGE RATIO OF

CAPACITY

COOLING

– 18 –

SOUND PRESSURE LEVEL

MODEL : RAM-40QH5 (Heating)

90

NC-70

NC-60

NC-50

NC-40

NC-30

NC-20

80

70

60

50

40

Sound pressure Level [dB]

30

20

10

63

Octave band Main wavelength [Hz]

125 250 500 1000 2000 4000 8000

APPROXIMATE
THRESHOLD HEARING
FOR CONTINUROUS
NOISE

– 19 –

SOUND PRESSURE LEVEL

MODEL : RAM-40QH5 (Cooling)

90

NC-70

NC-60

NC-50

NC-40

NC-30

NC-20

80

70

60

50

40

Sound pressure Level [dB]

30

20

10

63

APPROXIMATE
THRESHOLD HEARING
FOR CONTINUROUS
NOISE

Octave band Main wavelength [Hz]

125 250 500 1000 2000 4000 8000

– 20 –

MODEL RAM-40QH5

WIRING DIAGRAM

OUTDOOR UNIT

Remote Control

CIRCUIT DIAGRAM

– 21 –

1
2
3
4
5
6
7
8

10
11

13
14
15
16
17

19
20

9

12

18

SEG19

SEG18

SEG17
SEG16
SEG21
SEG24
SEG25
SEG26
SEG27
SEG28

NC

NC
NC
NC

NC

NC

NC

NC

NC

SEG20

SEG5
SEG0
SEG1
SEG2
SEG3
SEG4
SEG5
SEG6
SEG7
COM3
COM2
COM1
COM0
SEG14
SEG13
SEG12
SEG11
SEG13
SEG9
SEG8

40
39
38
37
36
35
34
33

31
30

28
27
26
25
24

22
21

32

29

23

40
39
38
37
36
35
34
33

31
30

28
27
26
25

32

29

64

63

62

61

60

59

58

57

56

55

54

53

52

51

50

49

48 47

46

45

44

43

41

42

65
66
67
68
69
70
71
72

74
75

77
78
79
80

73

76

1

2

3

4

5

6

7

8

9

10

11

12

13

14

15

16

17 18

19

20

21

22

24

23

SEG20
SEG21

SEG22

SEG23
SEG24
SEG25
SEG26
SEG27
SEG28
SEG29
SEG30
SEG31
SEG32
SEG33
SEG34
SEG35

SEG19

SEG18

SEG17

SEG16

SEG15

SEG14

SEG13

SEG12

SEG11

SEG10

SEG9

SEG8

SEG7

SEG6

SEG5

SEG4

SEG3

SEG2

SEG1

SEG0

SEG43

SEG42

SEG41

SEG40

P40

P41

P42

P43

P00

P01

P02

P03

P10

P11

P12

P13

D0

D1

D2

D3

D4

D5

D6

D7

D8

D9

BEEP

P20

P30
P31

NCVL C1

VL C2
VL C3
XC IN

XC OUT

VDD

X OUT

X IN

RESET

CARR

P23
P22

P21

VSS

IC 1
M3455OM6A-504FP

LCD 1

C8

50v/1u

K 1

D3

RB425D(1/2)

K2K3

K4

K5

P10

P11

P12

K6

K7 K8

K8 K10

K11K12

K18

K17

K15 K16

K13 K14

D0

D1

D2

D3

R1

100k

SW1

R2

P

100k

R3

100k

R4

100k

R5

Q1

2SC3443

or 2SC2982

R6

R7

R9

D2D1

D1 D2

EL-1L7

D3

(1/2)

RB425D

R10
12M

K19

X1

C9

R11

R15

R16

R13

R14

910kHz

105

104

104

150k

X2

kHz

C4

C5

C6

C7

18p

22p

R12
220k

220K

220k

100k

100k

32.768

C1

C2

C3

220p

220p

334

R6 R9

24(1/8W)

R8

330

SW-187-2P

Key matrix table

Input

D3D2D1

D0

Output

Door open Automatic swingFan speed selectionOperation selectionStart/Stop

Door shut ––Super silent coolingStart/Stop

Door open Day

• present timeHour downHour upOn timer

Door shut Super coolingRoom temperature downRoom temperature up–

Door open CancelReservation–Off timer

Door shut –––Sleep

P10

P11

P12

PRINTED WIRING BOARD LOCATION DIAGRAM

MODEL RAM-40QH5

– 23 –

MOUNTING

PCB SET

TYPE

– 25 –

MODEL RAM-40QH5

BLOCK DIAGRAM

OUTDOOR

OUTDOOR

MODEL RAM-40QH5

Indoor Unit 1

L

C1

D1

N

Magnetic relay

Rotor pole position
desition detector

Peak current cut off
circuit

Overload external
judgement circuit

Voltage amplification
circuit

Peak current
cut off

Electric
expansion valve

Power circuit

(For Indoor 2 P.W.B)

Power circuit

(Indoor and outdoor P.W.B)

Clock
circuit

Over heat thermistor

Defrost thermistor

Reversing valve coil

DC35V

C2

D2

Indoor Unit 2

Indoor / Outdoor
interface circuit 1

Indoor / Outdoor
interface circuit 2

Outdoor temperature thermistor

PAM Power
circuit

Outdoor fan motor

Power module

Trip signal

synthesis circuit

Upper arm drive

circuit

Lower arm drive

circuit

Relay drive

circuit

Relay circuit

Electric Expansion

valve drive circuit

Self-diagnosis

circuit

Outdoor micro computer (6M01)

DC compressor
motor

Inrush current

Protection circuit