Hitachi RUA-NP13ATS User manual

Installation, Operation and Maintenance
INSTRUCTIONS MANUAL
SELF-CONTAINED
AIR CONDITIONERS
Models：
：：
：
RUA-NP13ATS
RUA-NP15ATS
RUA-NP20ATS
RUA-NP25ATS
RUA-NP30ATS
REFRIGERANT:R410A
IMPORTANT:
READ AND UNDERSTAND THIS
INSTRUCTION MANUAL BEFORE
USING THIS AIR CONDITIONER.
KEEP THIS MANUAL FOR FUTURE
REFERENCE.
65MP3179

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.
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
Model
Condenser Air Inlet Temperature
-
Dry Bulb
-
Evaporator Air Inlet Temperature
-
Dry/Wet Bulb
-
Maximum
Minimum
Maxi
mum
Minimum
All Models 52°C
125°F
20°C
68°F
35°C / 21.5°C
95°F / 70.5°F
19.5°C / 14°C
67°F / 57°F
NOTES:
1. When the unit is operating at a condenser air inlet temperature of 52°C DB (125°F DB), the
maximum evaporator air inlet temperature shall be 18°C WB (64.4°F WB).
2. RUA-NP4ATS,RUA-NP5ATS,RUA-NP9ATS and RUA-NP10ATS: 80% to 120% of Nominal
Air Flow.RUA-NP6ATS and RUA-NP8ATS: 80% to 115% of Nominal Air Flow.
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.
DANGER
炰
烉
ˏDANGER
炰
ˏ
WARNING
炰
烉
ˏCAUTION
炰
烉
NOTE
烉

—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 ..........................................................................4
3.1 Main Power Wiring Procedures................................................................................ 4
3.2 Control Wiring .......................................................................................................... 4
3.3 Printed Circuit Board (PCB) Layout.......................................................................... 5
4. FAN SPEED ADJUSTMENT .................................................................9
5. REMOVING SHIPPING WASHERS....................................................10
6. TEST RUNNING..................................................................................11
6.1 Final Installation Check.......................................................................................... 11
6.2 Preparation............................................................................................................. 11
6.3 Test Running.......................................................................................................... 11
6.4 Test Running Record ............................................................................................. 12
6.5 Safety and Control Device Setting.......................................................................... 16
7. MAINTENANCE...................................................................................17
8. WINTER SHUTDOWN.........................................................................18
9. REPLACEMENT OF PARTS...............................................................18
10. TROUBLESHOOTING.........................................................................20

HITACHI SELF-CONTAINED AIR CONDITIONERS
OPERATION INSTRUCTIONS Models：
：：
：RUA-NP13ATS RUA-NP15ATS RUA-NP20ATS
RUA-NP25ATS RUA-NP30ATS
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
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?
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
flow to the room thermostat?
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

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 (see "Unit
General Data" in Technical CatalogⅠ)
(mm)
Model Unit Dimensions Minimum
Maintenance Space Minimum Air Intake Space
Maximum
Height of
Wall
a b h A B C D E H
RUA-NP13ATS 1,600 1,965 1,395 1,000 1,000 1,000 1,200 1,200 1,395
RUA-NP15ATS 1,600 1,965 1,395 1,000 1,000 1,000 1,200 1,200 1,395
RUA-NP20ATS 1,900 2,450 1,830 1,000 1,000 1,000 1,000 1,200 1,830
RUA-NP25ATS 1,900 3,000 1,670 1,000 1,000 1,000 1,000 1,400 1,670
RUA-NP30ATS 2,000 3,000 1,910 1,000 1,000 1,000 1,000 1,400 1,910
Fig. 1. Installation Space
NOTE:
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.

2
PREPARATION
Model Dimensions A B
deg. mm deg. mm
RUA-NP13ATS 0.4 14 0.6 17
RUA-NP15ATS 0.4 14 0.6 17
RUA-NP20ATS 0.4 17 0.6 20
RUA-NP25ATS 0.4 21 0.6 21
RUA-NP30ATS 0.4 21 0.6 21
Fig. 2. Foundation Gradient
Model Dimension (mm)
A
B
C
RUA-NP20ATS 2,308 1,968
RUA-NP25ATS 2,858 1,968
RUA-NP30ATS 2,858 2,068
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
For Models RUA-NP13ATS and RUA-NP15ATS For Models RUA-NP20ATS through RUA-NP30ATS

3
INSTALLATION
Model Dimensions (mm) Weight
(kg)
A B C D
RUA-NP13ATS 900 700 1,180 785 580
RUA-NP15ATS 900 700 1,180 785 610
RUA-NP20ATS 1,000 900 1,325 1,125 790
RUA-NP25ATS 1,000 900 1,650 1,350 900
RUA-NP30ATS 1,150 850 1,650 1,350 1,055
Fig. 4. Center of Gravity
2. INSTALLATION
2.1 Ducting Arrangement
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.
Fig. 5. Condensate Drain Connection
For Models RUA-NP13ATS through RUA-NP20ATS For Models RUA-NP25ATS and RUA-NP30ATS

4
ELECTRICAL WIRING
3. ELECTRICAL WIRING
Tools and Instruments – One set of wiring tools,
electrical tester (Clamp meter).
Schedule Check – Confirm that the field selected
electrical components (main power switch, fuses,
wires, conduit connections, wire terminals) are
properly selected according to "Electrical Data" in
Technical Catalog , and ensure that they complyⅠ
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
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 380V
and 415V 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) and also
Mp(N) for 380V and 415V power supplies
according to Fig. 6 or the wiring label attached
to the magnetic switch box.
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. 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.
(2) Do not operate the compressor by depressing
the button of the magnetic switch for the
compressor.
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.
3.2 Control Wiring
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. If a locally-supplied
thermostat and switch are installed, connect the
wiring according Technical Catalog Ⅰ.
Fig. 6. Field Wiring Connection

5
LED1
321 321 4 21 34 21 34 CT1-R CT1-S CT1-T
CT2-R CT2-S CT2-T
CT3-R CT3-S CT3-T
CT4-R CT4-S CT4-T
ML
SR T
N
1
CN7
CN6
BA ED F
SEG1
ML
SR T
N
1
PCB
PCB
ML
SR T
N
1
ELECTRICAL WIRING
3.3 Printed Circuit Board (PCB) Layout
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
The PCB in the Unit is operating with 4 types of DIP switches. The location is as follows:
Mark Name of Parts Mark Name of Parts
CT1-R,S,T Current Transformer for NO.1 Compressor DSW1 Dip Switch for Capacity Setting
CT2-R,S,T Current Transformer for NO.2 Compressor DSW2 Dip Switch for Optional Function Setting (1)
CT3-R,S,T Current Transformer for NO.3 Compressor DSW3 Dip Switch for Optional Function Setting (2)
CT4-R,S,T Current Transformer for NO.4 Compressor DSW4 Dip Switch for Optional Function Setting (3)
CN6 Connector for Transformer Input L,M Terminal for Different Main Power Supply
CN7 Connector for Transformer Output A,B,D,E,F Terminal for Room Thermostat
SW1 Switch for Alarm History Checking SEG1 Indicator for Information
3.3.2 Different Main Power Supply
When the main power supply is 380V (nominal voltage), be sure to change the wiring connected terminal
from L to M as shown figure below.
For 415V For 380V

6
21 34
21 34
21 34
21 34
21 34 21 34
21 3
ELECTRICAL WIRING
3.3.3 Factory Setting of Dip Switch (DSW)
DSW1: Capacity Settings
Capacity 13HP 15HP 20HP 25HP 30HP
Setting
Position
DSW2: DSW3: DSW4:
Optional Function Setting(1) Optional Function Setting(2) Optional Function Setting(3)
Function 13~30HP Function 13~30HP Function 13~30HP
Setting
Position
Setting
Position
Setting
Position
3.3.4 Optional Function Settings of Dip Switch (DSW2)
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 Setting (1)
Number of Compresser Dip Switch Setting
Force No.1 Compressor Stop
Force No.2 Compressor Stop
Force No.3 Compressor Stop
Force No.4 Compressor Stop
3.3.5 Alarm History Check
(1) First to push SW1 continually for more than 3 seconds.
(2) The indicator will flicker “ AL ” if the PCB already be in “ Alarm History Check ” mode.
(3) In “ Alarm History Check ” mode, each time to push SW1 can be showed alarm code by indicator,
total are 5 alarm codes for cyclical.
(4) To push SW1 continually for more than 5 seconds to clean all alarm record.
21 34
21 34
21 34 21 34
21 34

7
ELECTRICAL WIRING
3.3.6 Alarm Detect Function
(1) Each alarm code is composed of 2 digits for 1 set, or 4 digits for 2 sets.
(2) If the alarm code is composed of 1 set(2 digits) ：
(3) If the alarm code is composed of 2 sets(4 digits) ：
(4) If the system is operated under abnormal conditions, the alarm code will be showed as digits by the
indicator.
Alarm Code Description Check Item
—
03 Detect of CPU Error. The CPU of PCB Self-Checking.
(no need to check the item of unit)
—
05
Reverse or Phase Lack of Main Power
Source. Check the connection of main power supply. (Refer to 3.1 Main Power Wiring Procedures)
C1
08
Overheat forCompressor1.
(Internal thermostat for compressor1 acted) Check the Internal Thermostat of Compressor1.
C2
Overheat for Compressor2.
(Internal thermostat for compressor2 acted) Check the Internal Thermostat of Compressor2.
C3
Overheat for Compressor3.
(Internal thermostat for compressor3 acted) Check the Internal Thermostat of Compressor3.
C4
Overheat for Compressor4.
(Internal thermostat for compressor4 acted) Check the Internal Thermostat of Compressor4.
—
19 Overcurrent for Indoor Fan Motor. Check the Current for Indoor Fan Motor.
—
31 No Capacity Setting of Unit. Check the Setting of DSW1 Switch.
(Refer to 3.3.3 Factory Setting of DIP Switch)
C1
39
Overcurrent for Compressor Motor1. Check the Current for Compressor Motor1.
(Refer to 10.Troubleshooting)
C2 Overcurrent for Compressor Motor2. Check the Current for Compressor Motor2.
(Refer to 10.Troubleshooting)
C3 Overcurrent for Compressor Motor3. Check the Current for Compressor Motor3.
(Refer to 10.Troubleshooting)
C4 Overcurrent for Compressor Motor4. Check the Current for Compressor Motor4.
(Refer to 10.Troubleshooting)

8
ELECTRICAL WIRING
(Continued)
Alarm Code Description Check Item
C1
40
CT for Compressor1 Disconnected. Check the Connection for CT1.
C2 CT for Compressor2 Disconnected. Check the Connection for CT2.
C3 CT for Compressor3 Disconnected. Check the Connection for CT3.
C4 CT for Compressor4 Disconnected. Check the Connection for CT4.
C1
45
High Pressure Switch PS(H)1 Acted. Check the Discharge Pressure for
Compressor1.(Refer to 10.Troubleshooting)
C2 High Pressure Switch PS(H)2 Acted. Check the Discharge Pressure for
Compressor2.(Refer to 10.Troubleshooting)
C3 High Pressure Switch PS(H)3 Acted. Check the Discharge Pressure for
Compressor3.(Refer to 10.Troubleshooting)
C4 High Pressure Switch PS(H)4 Acted. Check the Discharge Pressure for
Compressor4.(Refer to 10.Troubleshooting)
C1
47
Low Pressure Switch PS(L)1 Acted. Check the Suction Pressure for
Compressor1.(Refer to 10.Troubleshooting)
C2 Low Pressure Switch PS(L)2 Acted. Check the Suction Pressure for
Compressor2.(Refer to 10.Troubleshooting)
C3 Low Pressure Switch PS(L)3 Acted. Check the Suction Pressure for
Compressor3.(Refer to 10.Troubleshooting)
C4 Low Pressure Switch PS(L)4 Acted. Check the Suction Pressure for
Compressor4.(Refer to 10.Troubleshooting)
F1
57
Overheat for Outdoor Fan Motor1.
(Internal thermostat for outdoor fan motor1
acted)
Check the Internal Thermostat of Outdoor Fan
Motor1.
F2
Overheat for Outdoor Fan Motor2.
(Internal thermostat for outdoor fan motor2
acted)
Check the Internal Thermostat of Outdoor Fan
Motor2.
F3
Overheat for Outdoor Fan Motor3 or 4.
(Internal thermostat for outdoor fan motor3
or
4 acted)
Check the Internal T
hermostat of Outdoor Fan
Motor3 or 4.
—
93
Power Supply Interrupted Less Than 2
seconds. Check the Main Power Supply.
—
94
Power Supply Interrupted More Than 2
seconds. Check the Main Power Supply.
—
dd
Wrong Wiring Connection for Room
Thermostat. Check the Connection for PCB Terminals A, D, E, and F.
NOTE:
1) If unit still under abnormal conditions, please contact your distributor.

9
FAN SPEED ADJUSTMENT
4. FAN SPEED ADJUSTMENT
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.
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 39 to 45 rpm.
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.
For Model RUA-NP13ATS and RUA-NP15ATS
Fig. 7-1. Adjustable Motor Pulley
Table 1-1. Fan Speed Adjustment
Models X：Regulation Space of Motor Pulley (mm)
PD：Pitch Diameter of Motor Pulley (mm) Factory Set Point
RPM/Turn
X 0 1 2 3 4 5 6 7 X RPM PD
RUA-NP13ATS
PD
112.0 108.8 105.7 102.6 99.4 96.3 93.1 90.0
4.5 800 97.9 39
RPM
915 890 865 840 810 785 760 735
RUA-NP15ATS
PD
112.0 108.8 105.7 102.6 99.4 96.3 93.1 90.0
2.6 850 103.8 39
RPM
920 890 865 840 815 790 765 730
RPM: Fan Speed (rpm)
PD : Pitch Diameter of Motor Pulley (mm)
RPM/Turn : Fan Speed Change per One Turn of Movable Motor Pulley
a b c
27 24 8

10
FAN SPEED ADJUSTMENT REMOVING SHIPPING WASHERS
For Model RUA-NP20ATS For Models RUA-NP25ATS and RUA-NP30ATS
Fig. 7-2. Adjustable Motor Pulley
Table 1-2. Fan Speed Adjustment
Models X：Regulation Space of Motor Pulley (mm)
PD：Pitch Diameter of Motor Pulley (mm) Factory Set
Point RPM/Turn
X 0 1 2 3 4 5 6 7 8 X RPM PD
RUA-NP20ATS
PD
132.0 128.7 125.2 122.2 118.9 115.7 112.4 109.1 105.8
6.0 780 112.4 46
RPM 920 895 870 850 830 805 780 760 740
RUA-NP25ATS
PD
150.0 146.9 143.7 140.5 137.3 134.1 131.0 127.7 124.6
7.5 860 126.1 43
RPM 1020 1000 980 960 940 915 895 870 850
RUA-NP30ATS
PD
150.0 146.9 143.7 140.5 137.3 134.1 131.0 127.7 124.6
4.0 940 137.3 43
RPM 1020 1000 980 960 935 915 895 870 850
RPM: Fan Speed (rpm)
PD : Pitch Diameter of Motor Pulley (mm)
RPM/Turn : Fan Speed Change per One Turn of Movable Motor Pulley
5. REMOVING SHIPPING WASHERS
These compressors are mounted on rubber isolators,
and are held rigidly during shipment by two sets of
shipping washers. Before compressor starting,
remove the yellow-painted shipping washers, the
compressor should float freely on the rubber
isolators.
a b c
31 28 8 a b c
41 38 10
Fig. 8. Removing Shipping Washers

11
TEST RUNNING
6. TEST RUNNING
6.1 Final Installation Check
Inspect the installation work according to all documents and drawings. Table 2 shows the minimum
checkpoints. Table 2. Installation Work Check List
6.2 Preparation
Tools and Instruments – High and Low Pressure
Compound Gauge(s), An Electric Tester, and
General Tools.
Preparation – Confirm that the system switch on
the room thermostat is at the OFF position.
Pressure Gauges – Equip high and low pressure
compound gauges according to Fig. 11.
Thermostat – Set the thermostat at a lower
temperature than the room temperature.
6.3 Test Running
Test running should be performed as follows,
when the unit is wired according to the wiring label.
1. Set the operation switch to the FAN position
and the system switch to the ON position, and
the evaporator fan will start immediately.
Check the rotation direction, fan speed and air
flow quantity through the evaporator.
2. Set the operation switch to the COOL position,
and the compressor and condenser fans will
start 3 minutes after this operation (refer to Fig.
9).
3. After system operation has become stabilized,
check the suction and discharge pressures on
the compound gauges. Normal operating
pressures are shown in Fig. 10.
4. Check the operating voltage, phase balance
and operating current.
5. Check to ensure that the thermostat functions
properly.
6. Check to ensure that the control and protective
devices function properly (refer to Table 3).
INSTALLATION WORK CHECK LIST
1.Is the unit solidly mounted and leveled?
2.Is the installation location adequate?
Space for Condenser Air Flow
Space for Maintenance Work
Noise and Vibration
Sunshine and Rainfall
Appearance
3.Is the ducting work adequate?
Filter Soundproofing
Size and Length Insulation
4.Are the condensate drain lines properly arranged?
Trap Drain Ditch
5.Is the electrical wiring system adequate?
Wire Size Tightened Connections
Switch Size Operation Control Devices
Fuse Size Safety Devices
Voltage Hz
6. Have the shipping washers been removed from the rubber-mounted compressor?

12
Fig. 9. Standard Operation Sequence
TEST RUNNING
6.4 Test Running Record
Compile test running records according to Table 4. Utilize these records for periodic operation checks, as
well as for troubleshooting.
Operational Sequence Chart


: ON 

: OFF
Operation
Equipments
Main Power Switch(*1) OFF
ON
Room Thermostat(*1)
FAN AUTO ON
AUTO
COOL OFF ON
TH
(Stage) COOLING CALL
1st … ON ON ON ON OFF ON
2nd … ON ON ON OFF OFF ON
Electric
Components
Indoor Fan Motor MIF 
       
Outdoor Fan Motor 1,2 MOF1,2 
       
Outdoor Fan Motor 3,4 MOF3,4 
       
RUA-
NP13ATS
and
RUA-
NP15ATS
Normal
Start (*2)
Compressor 1 MC1 
       
Compressor 2 MC2 
       
Reverse
Start (*2)
Compressor 1 MC1 
       
Compressor 2 MC2 
       
Start Delay Time
RUA-
NP20ATS
through
RUA-
NP30ATS
Normal
Start (*2)
Compressor
1,2 MC1,2 
       
Compressor
3,4 MC3,4 
       
Reverse
Start (*2)
Compressor
1,2 MC1,2 
       
Compressor
3,4 MC3,4 
       
Start Delay Time
Safety Devices Close Close Close Close Close Close Close Close Open
NOTES:
*1 ： Field supplied.
*2 ： Normal start and reverse start are triggered alternately by the actuation of the first stage switch
of room thermostat.
After
3 min.30 sec.
After 3 min.
After 3 min. and
After 3.5 min..
After 4 min. and
After 4.5 min.

13
TEST RUNNING
For Compressor Model E856DH For Compressor Model E506DH
Fig. 10-1 Nominal Operation Pressures for Model RUA-NP13ATS
Fig. 10-2 Nominal Operation Pressures for Model RUA-NP15ATS

14
TEST RUNNING
For Compressor Model E856DH For Compressor Model E506DH
Fig. 10-3 Nominal Operation Pressures for Model RUA-NP20ATS
Note:
Half dotted lines (– - –) marked for models
RUA-NP20ATS and RUA-NP25ATS indicate the
imaginary line for non-fan cycling control. Add the
following values for obtaining the pressures under
the fan cycling control.
(kg/cm
2
G)
Model Discharge Pressure
Suction Pressure
No.1
Cycle
No.2
Cycle
No.3
Cycle
No.1
Cycle
No.2
Cycle
No.3
Cycle
RUA-
NP20ATS
+6.0 +7.0 +6.0 +1.0 +1.0 +1.0
RUA-
NP25ATS
+2.0 +2.0 +2.0 +1.0 +1.0 +1.0
Fig. 10-4 Nominal Operation Pressures
for Model RUA-NP25ATS

15
TEST RUNNING
Fig. 10-5 Nominal Operation Pressures for Model RUA-NP30ATS

16
TEST RUNNING
6.5 Safety and Control Device Setting
Table 3. Safety and Control Device Setting
Models RUA-NP13ATS RUA-NP15ATS RUA-NP20ATS RUA-NP25ATS RUA-NP30ATS
For Compressor E856DH /
E506DH
E856DH
E856DH/
E506DH/ E856DH
E856DH E856DH
High Pressure Switch Automatic Reset, Non-Adjustable
Cut-Out
Cut-In
MPa
kg/cm
2
G
MPa
kg/cm
2
G
4.15
42.3
3.2
32.6
4.15
42.3
3.2
32.6
4.15
42.3
3.2
32.6
4.15
42.3
3.2
32.6
4.15
42.3
3.2
32.6
Low Pressure Switch Automatic Reset, Non-Adjustable
Cut-Out
Cut-In
MPa
kg/cm
2
G
MPa
kg/cm
2
G
0.40
4.1
0.70
7.1
0.40
4.1
0.70
7.1
0.40
4.1
0.70
7.1
0.40
4.1
0.70
7.1
0.40
4.1
0.70
7.1
Overcurrent Transformer Automatic Reset, Non-Adjustable
Cut-Out A 18.0/10.6 18.0 18.0/10.6 18.0 18.0
Internal Thermostat Automatic Reset, Non-Adjustable
Cut-Out
Cut-In °C °C 130 108 130 108 130 108 130 108 130 108
CCP Timer for
Compressor
(Building on PCB)
Non-Adjustable
No.1
No.2
No.3
No.4
min.
min.
min.
min.
3
3.5
—
—
3
3.5
—
—
3
3.5
4
—
3
3.5
4
—
3
3.5
4
4.5
For Evaporator Fan Motor Manual Reset, Adjustable
Overcurrent Relay A 6 6 8 11 11
For Condenser Fan Motor
Internal Thermostat Automatic Reset, Non-Adjustable
Cut-Out
Cut-In °C °C 160 130 160 130 160 130 160 130 160 130
Pressure Switch for Fan
Cycling Control Automatic Reset, Non-Adjustable
Cut-Out (Stop)
Cut-In (Operation) MPa MPa — —— —1.72 2.17 1.72 2.17 — —
For Control Circuit Fuse
Capacity A 2.5 2.5 2.5 2.5 2.5