Hitachi RAM-90NP5B User manual

NO. 0586E
SPECIFICATIONS AND PARTS ARE SUBJECT TO CHANGE FOR IMPROVEMENT
ROOM AIR CONDITIONER
OUTDOOR UNIT
FEBRUARY 2015 Refrigeration & Air-Conditioning Division
SERVICE MANUAL
PM
REFER TO THE FOUNDATION MANUAL
TECHNICAL INFORMATION
FOR SERVICE PERSONNEL ONLY
CONTENTS
SPECIFICATIONS------------------------------------------------------ 5
INSTALLATION---------------------------------------------------------16
CONSTRUCTION AND DIMENSIONAL DIAGRAM---------20
WIRING DIAGRAM ---------------------------------------------------21
MAIN PARTS COMPONENT --------------------------------------23
CIRCUIT DIAGRAM --------------------------------------------------25
BLOCK DIAGRAM ----------------------------------------------------27
PRINTED WIRING BOARD LOCATION DIAGRAM --------28
BASIC MODE ----------------------------------------------------------33
REFRIGERATING CYCLE DIAGRAM---------------------------53
DESCRIPTION OF MAIN CIRCUIT OPERATION-----------54
TROUBLE SHOOTING ----------------------------------------------65
PARTS LIST AND DIAGRAM--------------------------------------79
After installation
(W)
(A)
COOLING CAPACITY
DC INVERTER FIVE SYSTEM MULTI
TYPE
MODEL
POWER SOURCE
TOTAL INPUT
TOTAL AMPERES
SPECIFICATIONS
RAM-90NP5B
HEATING CAPACITY
DIMENSIONS (mm)
NET WEIGHT
1ø, 220 - 240V, 50/60Hz
W
H
D
(kg)
(kW)
(B.T.U.)
REFER TO THE SPECIFICATIONS PAGE
OUTDOOR UNIT
RAM-90NP5B
RAM-90NP5B
950
800
370
74
HITACHI

– 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 the 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 after reinforced or at
a new location.
10. Any inflammable object must not
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.






– 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 (I.C.)
(3) Field-effective transistor (F.E.T.)
(4) P.C. boards or the like to 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 1M 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 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 solder 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 short circuit 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 nearby, it is recommend to stop the operation and to disconnect the power cord plug
from the power outlet for safety.
3. In the event of power failure, the air conditioner will restart automatically in the previously selected mode
once the power is restored. In the event of power failure during TIMER operation, the air conditioner will
not start automatically. Re-press ON/OFF button after 3 minutes from when the unit off or power recovery.
4. If the room air conditioner is stopped by adjusting thermostat, or miss operation, 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 (TEST SWITCH)
TRANSFORMER
VARISTOR
NOISE SUPPRESSOR
THERMOSTAT
REMOTE CONTROL SWITCH (LIQUID CRYSTAL)
138 W
NO
NO
NO
YES
YES
20A, 5.0A
G4A
NO
NO
YES
NO
ERZVA9V431
YES
YES(IC)
NO
2700g
WITHOUT REFRIGERANT BECAUSE
COUPLING IS FLARE TYPE.
UNIT
PIPES
REFRIGERANT CHARGING
VOLUME
(Refrigerant 410A)
RAM-90NP5B
JU182XC1
MAX. 75m
In case the pipe length is more than 30m, add refrigerant R410 at 15gram per every meter exceeds.

– 6 –
SPECIFICATIONS FOR INDOOR UNITS COMBINATION
OPERATION SCOPE
TYPE DC INVERTER FIVE SYSTEM MULTI COOLING AND HEATING
MODEL OUTDOOR UNIT
PHESE/VOLTAGE/FREQUENCY
CIRCUIT AMPERES TO CONNECT (A)
COOLING
(FIVE UNITS)
CAPACITY (kW)
(B.T.U./h)
TOTAL INPUT (W)
EER (B.T.U./hW)
TOTAL AMPERES (A)
POWER FACTOR (%)
HEATING
(FIVE 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-90NP5B
1ø, 220 - 240V, 50/60Hz
25
8.5
29,020
2,230
13.01
10.20 - 9.40
99
11.00
37,540
2,460
15.26
11.3 - 10.4
99
MAX. 75m (FIVE UNIT TOTAL)
CE (EMC&LVD)
RAM-90NP5B
MODEL
W
PACKING
(mm)
H
D
cu.ft.
1,037
896
417
13.68
75
GROSS WEIGHT (kg)
6.35DX5/9.52DX3/12.70X2
FLARE NUT SIZE (SMALL/LARGE)
INDOOR SUCTION
TEMPERATURE (˚C)
COOLING OPERATION SCOPE
OUTDOOR SUCTION
TEMPERATURE (˚C)
INDOOR SUCTION
HUMIDITY (%)
HEATING OPERATION
SCOPE
16 - 32 –10 ~ 43 BELOW 80
BELOW 27 –15 ~ 21 —

– 7 –
DC INVERTER SYSTEM MULTI R.A.C. RAM-90NP5B
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.
(Reference value)
5 ROOM MULTI-SPLIT INVERTER TYPE RAC : RAM-90NP5B
POSSIBLE COMBINATION TO OPERATE (SAME TIME OPERATION)

– 8 –

– 9 –
RATING CONDITON (DRY BLUB / WET BULB)
COOLING
HEATING
INDOOR OUTDOOR
27 / 19 ˚C
20 / –˚C
35 / 24˚C
7 / 6˚C
<REMARKS>
* ONE UNIT INDICATED ARE ONLY FOR ONE UNIT OPERATION WHEN TWO OR MORE INDOOR UNITS ARE CONNECTED.
* TWO UNITS INDICATED ARE ONLY FOR TWO UNITS OPERATION WHEN TWO OR MORE INDOOR UNITS ARE CONNECTED.
* THREE UNITS INDICATED ARE ONLY FOR THREE UNITS OPERATION WHEN THREE OR MORE INDOOR UNITS ARE CONNECTED.
* FOUR UNITS INDICATED ARE ONLY FOR FOUR UNITS OPERATION WHEN FOUR OR FIVE INDOOR UNITS ARE CONNECTED.
Two indoor units should be connected at least.
Total nominal cooling capacity should not be more than 15.5kW.