Hitachi RUA-NP20ATS User manual

IMPORTANT:
READ AND UNDERSTAND THIS
INSTRUCTION MANUAL BEFORE
USING THIS AIR CONDITIONER.
KEEP THIS MANUAL FOR FUTURE
REFERENCE.
INSTRUCTIONS MANUAL
Installation, Operation and Maintenance
65MP3208
REFRIGERANT:R410A
Models:
AIR CONDITIONERS
RUA-NP30ATS
RUA-NP20ATS
SELF-CONTAINED

Model
M
a
x
i
m
u
m
Min
i
m
u
m
M
a
x
i
m
u
m
M
in
i
m
u
m
All
Models
43°C
109°F
21°C
70°F
32°C /
22.5°C
90°F /
72.5°F
21°C /
15.5°C
70°F /
60°F
IMPORTANT NOTICE
 HITACHI pursues a policy of continuing improvement in design and performance of products.
The
right is therefore reserved to vary specification without
notice.
 HITACHI cannot anticipate every possible circumstance that might involve a potential hazard.
 No part of this manual may be reproduced without written
permission.
 Signal words (DANGER, WARNING and CAUTION) are used to identify levels of
hazard
seriousness. Definitions for identifying hazard levels are provided below with their respective
signal
words.
:
:
:
NOTE :
Immediate hazards which WILL result in severe personal injury
or
death.
Hazards or unsafe practices which COULD result in severs
personal
injury or
death.
Hazards or unsafe practices which COULD result in minor
personal
injury or product or property
damage.
Useful information for this operation and/or
maintenance.
 If you have any questions, contact your contractor or dealer of HITACHI
.
 This manual gives a common description and information for this air conditioner which you
operate as well as for other models.
 This air conditioner has been designed for the following temperatures. Operate the air conditioner
within this range
.
Condenser Air Inlet Temperature and Evaporator Air Inlet
Temperature
This manual should be considered as a permanent part of the air conditioning equipment and should
remain with the air conditioning equipment
Hitachi’s air conditioners are designed and manufactured based on using the specified refrigerants. The applicable
refrigerants are specified to each unit models. However, in the global sites, it is revealed that charging different type
of refrigerants instead of the specified refrigerants. This action may cause mechanical troubles, malfunction and
failure, and in the worst case, it endangers
safety
seriously and may cause a fire or an explosion.
Therefore, do not charge the non-specified refrigerants or others in the refrigerant cycle of the unit as follows:
 Hydrocarbon Refrigerants such as Propane or etc.
 Oxygen, Flammable Gases such as Acetylene or etc.
 Poisonous Gases.
The types of charging refrigerants are indicated in the Installation and Maintenance Manuals, Technical Catalogs,
Service Manuals and the
specification
label in the each unit. Be aware that Hitachi does not take any
responsibility
for unit failure, troubles of malfunction, and any accidents caused by charging the
non-specified refrigerants or others such as above.
Condenser Air Inlet Temperature
-Dry Bulb-
Evaporator Air Inlet Temperature
-Dry/Wet Bulb-

— CONTENTS —
No. Item .................................................................................................. Page
Operation Instructions.......................................................................... Ⅰ
1. PREPARATION ................................................................................... 1
1.1 Initial Check........................................................................................................... 1
1.2 Transportation ....................................................................................................... 1
1.3 Placing the Unit ..................................................................................................... 2
2. INSTALLATION .................................................................................. 3
2.1 Ducting Arrangement ............................................................................................ 3
2.2 Condensate Drain Piping ...................................................................................... 3
3. ELECTRICAL WIRING ....................................................................... 3
3.1 Main Power W iring P rocedures ............................................................................. 3
4. FAN SPEED ADJUSTMENT ............................................................... 6
5. REMOVING SHIPPING WASHERS ................................................... 6
6. TEST RUNNING ................................................................................. 7
6.1 Final Installation Check ......................................................................................... 7
6.2 Preparation............................................................................................................ 7
6.5 Safety and Control Device Setting......................................................................... 9
7. MAINTENANCE................................................................................... 10
8. WINTER SHUTDOWN......................................................................... 11
9. REPLACEMENT OF PARTS ............................................................... 11
......................................................................................................... 7
10. TROUBLESHOOTING......................................................................... 13
6.3 Test Running
6.4 Test Running Record ............................................................................................ 8
3.2 Control W iring ....................................................................................................... 4
3.3 Printed Circuit Board (PCB) Layout .......................................................................... 4

Starting Procedures
1. Switch ON the main power source to the unit. 2. Set the operation switch of the room thermostat
to the desired operation position. FAN –Ventilation Operation COOL –Cooling Operation
3. Set the thermostat knob of the room thermostat
to the desired temperature.
4. Set the system switch of the room thermostat to
the ON positions.
Stopping Procedures
1. Set the system switch to the OFF position. 2. Switch OFF the main power source to the unit.
Troubleshooting Poor Cooling Operation
1. Are there any obstacles, which hamper
sufficient air to the condenser?
2. Check to ensure that the thermostat is set at the
desired position.
3. Check the air filter for clogging. 4. Are there any obstacles, which hamper free air
Please contact your service shop if the trouble is still not solved.
Maintenance
1. Clean or replace the filter. 2. Clean the cabinet with cleaner. 3. Clean the condensate drain pan and the drain
piping.
4. Clean the condenser. It is recommended that a
specialist be contacted for this type of work.
5. Check for abnormal sounds and vibration. Stop
the unit and contact your service shop, if observed.
Ⅰ
HITACHI SELF-CONTAINED AIR CONDITIONERS
Unit Does Not Start
1. Is the main power source switch to the unit ON? 2. Is the main fuse normal? 3. Is the phase of main power source right?
OPERATION INSTRUCTIONS Models：RUA-NP20ATS RUA-NP30ATS
flow to the room thermostat.

1
PREPARATION
1. PREPARATION
1.1 Initial Check
Required Materials –Measure, Architectural
Information Regarding Installation Location.
Installation Location –Confirm that the final
Installation location is provided with convenient
piping and wiring work. Strong water runoff should
be avoided.
Installation Space –Check for obstacles, which
restrict condenser airflow or hamper maintenance
work in the space specified in Fig. 1.
Foundation –Check to ensure that the
foundation is flat, level, and sufficiently strong,
taking into account the maximum foundation
gradient (Fig. 2) and the unit weight balance.
Confirm elevation provision for the unit on a solid
base with an iron frame or concrete curbs shown
in Fig. 3, in order to obtain proper clearance
beneath the unit for either rooftop or
on-the-ground installation. Additionally, for
on-the-ground installation, provide a gravel or
concrete space around the condenser air intake,
in order to avoid airflow obstruction due to grass
or other vegetation.
Unit –Check to ensure that the unit has been
transported without damage. File a damage claim
with the transportation companies if mishandling
due to transportation company negligence is
suspected.
1.2 Transportation
Secure the route to the final installation location
by confirming the packing dimensions.
(mm)
Minimum
Maintenance Space
Minimum Air
Intake Space
Maximum
Height of
Wall
ab h A B C D E H
Unit Dimensions
Model
When the unit is installed at a location, which is encircled with walls and obstruction to free air
circulation is suspected, consult HITACHI regarding the operation space.
Fig. 1. Operation Space
NOTE:
RUA-NP30ATS 2,000 2,450 1,910 1,000 1,000 1,000 1,000 1,400 1,910
RUA-NP20ATS 1,600 2,120 1,560 1,000 1,000 1,000 1,000 1,400 1,910

2
PREPARATION
Model
Dimensions
A
B
deg.
mm
deg.
mm
Fig. 3. Recommended Concrete Curbs
1.3 Placing the Unit
Tools and Instruments –Pincers, Wrenches,
Facilities to Transport and Place the Unit.
Transportation –Transport the unit as close to
the final installation location as practical before
unpacking is performed. Keep the unit upright.
When transporting the unit after unpacking has
been performed, take note of the following.
Rolling –Place three equal - sized rollers under
the base frames. Each roller must carry both of
the outer frames, and must be situated to balance
the unit (refer to the center of gravity in Fig. 4).
Lifting by Forklift –Insert the forks under the base
frames from the indicated direction in Fig.4. Lift the
unit, exercising care to catch both of the outer frames.
Rigging –Apply spreader bars to the top of the unit,
in order to prevent damage to the unit due to cable
scratches.
Unpacking –Follow the instructions marked on the
packing.
NOTES:
1. Keep the unit covered with a vinyl cover during installation work for peripheral equipment.
2. Do not expose the unit under the direct sunshine.
Dimensions (mm)
Fig. 2. Foundation Gradient
0.4 21 0.6 21
RUA-NP30ATS
RUA-NP20ATS 0.4 140.6 17
For Model RUA-NP30ATS
For Model RUA-NP20ATS
2,308 2,068
RUA-NP30ATS
A B
RUA-NP20ATS 1,970 1,540
Model

3
INSTALLATION
2. INSTALLATION
Tools and Instruments –General tools for
ducting.
Connection –Pre-drilled duct flanges are
provided at the supply and return air duct
connections. A field-supplied or optional filter box
with filter must be installed at a proper location in
the return air duct. It is recommended that flexible
duct connections be installed to minimize sound
and vibration transmission. All ducts running
outside must be sufficiently insulated and
weatherproofed.
2.2 Condensate Drain Piping
Tools and Instruments –General piping tools.
Drain Trap –A female piping thread screw
connection is provided at side of the unit.
Dimension "L" in Fig. 5 should be sufficiently
longer than the negative fan pressure at the drain
connection (50mm to 100mm, depending on the
return air duct design). Always fill the trap with
water.
For Models RUA-13AT3S and RUA-15AT3S
Fig. 5. Condensate Drain Connection
Fig. 4. Rolling,Lifitng and Rigging
2.1 Ducting Arrangement
3. ELECTRICAL WIRING
Tools and Instruments –One set of wiring tools,
electrical tester (Clamp meter).
Confirm that electrical power is not being supplied
to the installation location prior to any electrical
installation work.
1. Install the field-supplied main switch box at the
properly selected location.
2. Install conduit connectors in the hole for power
wiring (knockout holes).
3. Lead the main power wires and the earthing
wire through the connector to the screw
terminals for main power and earthing in the
magnetic switch box. The neutral wire to 220V
power supplies should also be led through the
connector. Firmly connect the wires with wire
terminals to the unit screw terminals R(L1),
S(L2) and T(L3) for 220V power supplies
according to Fig. 6 or the wiring label attached
to the magnetic switch box.
Schedule Check –Confirm that the field selected
electrical components (main power switch, fuses,
wires, conduit connections, wire terminals) are
properly selected and ensure that they comply
with national and local codes. It is recommended
that the main power switch be locked at the OFF
position, to prevent against accidental supply of
the power during unit servicing.
Service Panel –Access to the magnetic switch
box is provided from the service panel, which is
fixed with screws (see the panel location in the
Operation Instructions.)
3.1 Main Power Wiring Procedures
A scroll compressor is equipped. Because that
the rotation direction of the orbiting scroll of the
HITACHI scroll type compressor is fixed,
therefore a reverse & single phase sequence
protection relay is equipped in this unit.
ELECTRICAL WIRING

ELECTRICAL WIRING
All DSW were set correctly at factory, do not change settings of DSW. The following figures are only for
reference in installation. After installation, make sure all DSW were set as factory setting.
3.3.1 PCB Drawing
3.3.2 Factory Setting of Dip Switch (DSW)
DSW1: Capacity Settings
DSW2: Optional Function Settings (1)
Setting
Position
ON
1 2
3
Setting
Position
ON
1 2
34
Setting
Position
ON
1 2
34
DSW3: Optional Function Settings (2)
The PCB in the Unit is operating with 3 types of DIP switches. The location is as follows:
R S T Mp
Unit Side
If each phase R, S or T of the power source is
incorrectly connected, the compressor does not
start due to the activation of the reverse & single
phase sequence protection relay. Therefore, in
order to check the correct wiring connection, the
utilization of a phase sequence indicator is
recommended when the unit is started after
installation of the unit.
(1) If the phase is wrong, exchange two of the
three wires connected from the main power
source to the main terminals of the unit as
indicated with dotted lines, and then check the
rotation direction of the phase sequence
indicator once again. Do not exchange the
wires in the unit in order to protect the
compressor against the reversal rotation.
3.2 Control Wiring
(2) Do not operate the compressor by depressing
the button of the magnetic switch for the
compressor.
Install the optional room thermostat at a suitable
location in the space to be air-conditioned.
Connect the control wires between the unit
terminals and the thermostat terminals according
to Fig. 6 or the wiring label.
A three-phase condenser fan motor is equipped;
therefore, the fan motor rotation should be
checked. Interchange two of the three main power
source wires, if incorrect rotation is detected
during initial start-up.
Power Source Fig. 6. Field Wiring Connection
4
3.3 Printed Circuit Board (PCB) Layout

3.3.3 Optional Function Settings of Dip Switch (DSW2,3)
Before setting DSW, firstly turn off power source and set the position of the DSW. If the switches are set
without turning off the power source, the contents of the setting are invalid. Mark of “■”indicates the
position of dip switch.
DSW2: Optional Function Settings (1)
Dip Switch
Setting
Force No.1 Compressor Stop
Force No.2 Compressor Stop
Force No.3 Compressor Stop
3.3.4 Alarm Detect Function
If the system is operated under abnormal conditions, during the test running or in normal operate, the
red lamp of the PCB flickers. The states of red lamp flickers are indicated in following Table.
State of
Red Lamp Flickers
Description
Check Item
Continue Light
Normal
—
Once
Reverse or Single Phase of
Main Power Source
1)Check the connection of main power supply.
(Refer to 3.1 Main Power Wiring Procedures)
Twice
Incorrect Wiring Connection
of Room Thermostat
1)Check wiring and connections between unit and
thermostat. (Refer to 3. 2 Control Wiring)
3 Times
Trip Detected of Safety Device
1)Check the current for indoor fan motor.
2)Check the current for outdoor fan motor.
3)Check the pressure of discharge and suction line.
(Refer to 16. Troubleshooting)
4)Check the internal thermostat of compressor.
4 Times
Overcurrent of Compressor
1)Check the current for compressor motor.
2)Check the pressure of discharge and suction line.
(Refer to 16. Troubleshooting)
3)Check the resistance of current transformer by
tester.(Refer to Wiring Nameplate)
Notes:
1) The Red Lamp Flickers cycle will continue showing at intervals of 3 seconds until the Indication
problem be solved.
2) If unit still under abnormal conditions, please contact your distributor.
ON
123
ON
123
ON
123
5 Times Detect of Power Off 1)Check the main power supply.
(No need to check the item of unit)
2)Check the Current for Compressor Motor.
Abnormal Current Detection
1)Check the setting of DSW1 switch.
7 Times No Capacity Setting of Unit
1)The CPU of PCB self-checking.
6 Times Wrong Detect of CPU
Low Current of Compressor or
8 Times
(Refer to 3.3.2 Factory Setting of Dip Switch)
1)Check the main power supply.
5
ELECTRICAL WIRING

The unit is equipped with an adjustable motor
pulley. The fan speed can be varied through a
given range by adjustment of the pulley. Table 1.
shows the setting speed and the variable speed
range. To change the speed, adjust the motor
pulley as follows (refer to Fig. 7).
1. Loosen the two bolts on the adjusting bracket
for the fan belt tension and loosen the belt by
pushing the motor upward.
2. Loosen the set screw in the movable pulley
flange.
4. Tighten the set screw in the movable pulley,
which is positioned over the flat surfaces of the
fixed pulley.
5. Adjust the belt tension (approximately 20 mm
deflection with one finger) by pushing the motor
downward and tightening the bolts on the
adjusting bracket.
3. Turn the movable pulley flange toward the fixed
flange to increase the speed, and turn it away
from the fixed flange to decrease the speed.
Each turn of the movable flange will increase or
decrease the fan speed by 32 rpm.
Fig. 7. Adjustable Motor Pulley
Table 1. Fan Speed Adjustment
RPM: Fan Speed (RPM)
PD* : Pitch Diameter of Motor Pulley (mm)
RPM/Turn**: Fan Speed Change per One Turn of Movable Motor Pulley Flange (RPM per Turn)
5. REMOVING SHIPPING WASHERS
Fig.8-1. Removing Shipping Washers
Compressor is mounted on rubber isolators, and is held rigid during shipment by two sets of shipping
washers (refer to Fig. 8-1). Before starting the compressor, remove the yellow-painted shipping washers, the
compressor should float freely on the rubber isolators.
6
REMOVING SHIPPING WASHERS
4. FAN SPEED ADJUSTMENT
FAN SPEED ADJUSTMENT