Hitachi RUA-NP5ATS User manual

Installation, Operation and
Maintenance
INSTRUCTIONS MANUAL
SELF-CONTAINED
AIR CONDITIONERS
Models ：
RUA-NP5ATS
RUA-NP8ATS
RUA-NP10ATS
RUA-NP15ATS
REFRIGERANT:
R410A
IMPORTANT:
READ AND UNDERSTAND
THIS
INSTRUCTION MANUAL
BEFORE
USING THIS AIR
CONDITIONER.
KEEP THIS MANUAL FOR
FUTURE
REFERENCE.
65MP3212

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 ....................................................................... 4
3.1 Main Power W iring P rocedures ............................................................................. 4
3.2 Control W iring ....................................................................................................... 4
4. FAN SPEED ADJUSTMENT ............................................................... 5
5. REMOVING SHIPPING WASHERS ................................................... 6
6. TEST RUNNING ................................................................................. 7
6.1 Final Installation Check ......................................................................................... 7
6.2 Preparation............................................................................................................ 7
6.3 Test Running ......................................................................................................... 7
6.4 Test Running Record ............................................................................................ 8
6.5 Safety and Control Device Setting......................................................................... 9
7. MAINTENANCE................................................................................... 10
8. WINTER SHUTDOWN......................................................................... 11
9. REPLACEMENT OF PARTS ............................................................... 11
10. TROUBLESHOOTING......................................................................... 13

Ⅰ
HITACHI SELF-CONTAINED AIR
COND
I
T
I
ONERS
OPERATION INSTRUCTIONS Models：RUA-NP5ATS
RUA-NP8ATS
RUA-NP10ATS
RUA-NP15ATS
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.

1
1.
PREPARATION
1.1 Initial
Check
Required Materials – Measure,
Archi t ec t ural
Information Regarding Installation
Loca t ion .
Installation Location – Confirm that the
f inal
Installation location is provided with
convenien t
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
f ounda t ion
is flat, level, and sufficiently strong, taking
in t o
account the maximum foundation gradient (Fig.
2)
and the unit weight balance. Confirm
eleva t ion
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
f or
PREPARATION
either rooftop or on-the-ground
ins t alla t ion .
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
vege t a t ion .
Unit – Check to ensure that the unit has
been
transported without damage. File a damage
claim
with the transportation c ompanies if
mishandling
due to transportation company negligence
is
suspec t ed .
1.2
Transportation
Secure the route to the final installation location
by
confirming the packing dimensions (see
" Uni t
General Data" in Technical Catalog I
.)
(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-NP5ATS 1 , 020 1 , 475 1 , 070 1 , 000 1 , 000 1 , 000 1 , 200 1 , 200 1 , 070
RUA-NP8ATS 1 , 020 1 , 475 1 , 070 1 , 000 1 , 000 1 , 000 1 , 200 1 , 200 1 , 070
RUA-NP10ATS 1 , 360 1 , 750 1 , 070 1 , 000 1 , 000 1 , 000 1 , 000 1 , 200 1 , 070
RUA-NP15ATS 1 , 430 2 , 140 1 , 070 1 , 000 1 , 000 1 , 000 1 , 000 1 , 200 1 , 070
NOTE :
Fig. 1. Operation
Space
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-NP5ATS 0 . 4 10 0 . 6 11
RUA-NP8ATS 0 . 4 10 0 . 6 11
RUA-NP10ATS 0 . 4 12 0 . 6 14
RUA-NP15ATS 0 . 4 15 0 . 6 15
Fig. 2. Foundation
Gradient
Model
Dimension
(mm)
a b
RUA-NP5ATS
960 1 , 435
RUA-NP8ATS 960 1 , 435
RUA-NP10ATS 1 , 300 1 , 709
RUA-NP15ATS 1 , 370 2 , 102
Fig. 3. Recommended Concrete
Curbs
1.3 Placing the
Unit
Tools and Instruments – Pincers,
Wrenches,
Facilities to Transport and Place the
Uni t.
Transportation – Transport the unit as close
t o
the
final installation location as practical
be f ore
unpacking is performed. Keep the unit
uprigh t.
When transporting the unit after unpacking
has
been performed, take note of the
f ollowing .
Rolling – Place three equal - sized rollers
under
the base frames. Each roller must carry both of
t he
outer frames, and must be situated to balance
t he
unit (refer to the center of gravity in Fig.
4) .
Lifting by Forklift – Insert the forks under
t he
base frames from the indicated direction in
Fig . 4 .
Lift the unit, exercising care to catch both of
t he
outer
f rames .
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
.

3
INSTALLATION
Model
Dimensions
(mm)
Weight
(kg)
A B C D
Fig. 4. Center of
Gravity
2.
INSTALLATION
2.1 Ducting
Arrangement
Tools and Instruments – General tools
f or duc t ing .
Connection – Pre-drilled duct flanges
are
provided
at the supply and return air
duc t
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
f lexible
duct
connections be installed to minimize
sound
and
vibration transmission. All ducts
running
outside
must be sufficiently insulated
and wea t herproo f ed .
2.2 Condensate Drain
Piping
Tools and Instruments – General piping
t ools .
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
RUA-NP15ATS
800 625
780 1300 450
RUA-NP10ATS 810 550 690 1000
40
0
RUA-NP8ATS 615 405 685 730 250
RUA-NP5ATS 615 405 685 730 240

4
ELECTRICAL
WIRING
3. ELECTRICAL
WIRING
Tools and Instruments – One set of wiring
t ools ,
electrical tester (Clamp
me t er) .
Schedule Check – Confirm that the field
selec t ed
electrical components (main power switch,
f uses ,
wires, conduit connections, wire terminals)
are
properly selected according to "Electrical Data"
in
Technical Catalog Ⅰ, 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
o f
the power during unit
servicing .
Service Panel – Access to the magnetic
swi t ch
box is provided from the service panel, which
is
fixed with screws (see the panel location in
t he
Operation
I ns t ruc t ions . )
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
t he
properly selected
loca t ion .
2. Install conduit connectors in the hole for
power
wiring (knockout
holes) .
3. Lead the main power wires and the
ear t hing
wire through the connector to the
screw
terminals for main power and earthing in
t he
magnetic switch box. The neutral wire to
220V
power supplies should also be led
t hrough
the
connector. Firmly connect the wires
wi t h
wire terminals to the unit screw
t erminals
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 .
A scroll compressor is equipped. Because
t ha t
the rotation direction of the orbiting scroll of
t he
HITACHI scroll type compressor is
f ixed ,
therefore a reverse & single phase
sequence
protection relay is equipped in this unit. If
each
phase R, S or T of t h e power source
is
incorrectly connected, the compressor does
no t
start due to the activation of the reverse &
single
phase sequence protection relay. Therefore,
in
order to check the correct wiring connection,
t he
utilization of a phase sequence indicator
is
recommended when the unit is started
a ft er
installation of the
uni t.
(1) If the phase is wrong, exchange two of
t he
three wires connected from the main
power
source to the main terminals of the unit
as
indicated with dotted lines, and then check
t he
rotation direction of the phase
sequence
indicator once again. Do not exchange the
wires in the unit in order to protect
t he
compressor against the reversal
ro t a t ion .
Unit
Side
R S
T
(2) Do not operate the compressor by
depressing
the button of the magnetic switch for
t he
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
sui t able
location in the space to be
air-condi t ioned .
Connect
the control wires between the
uni t
terminals and the
thermostat terminals
according
to Fig. 6 or the
wiring
label .
Fig. 6. Field Wiring
Connection
Power Source

5
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
bracke t
for the fan belt tension and loosen the belt
by
pushing the motor
upward .
2. Loosen the set screw in the movable pulley
f lange .
FAN SPEED
ADJUSTMENT
3. Turn the movable pulley flange toward the
f ixed
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 40 to 45
rpm .
4. Tighten the set screw in the movable pulley
,
which is positioned over the flat surfaces of
t he
fixed
pulley .
5. Adjust the belt tension (approximately 20
mm
deflection with one finger) by pushing the
mo t or
downward and tightening the bolts on
t he
adjusting
bracket .
Fig. 7. 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
Poin t
RPM / Turn**
X 0 1 2 3 4 5 6 7 X
RPM PD*
PD 112 109 106 103 99 96 93 90
RUA-NP5ATS
RPM 1,120 1,090 1,060 1,025 995 960 930 900 7 900 90 45
RUA-NP8ATS
RPM 1,120 1,090 1,060 1,025 995 960 930 900 7 900 90 45
RUA-NP10ATS
RPM 1,120 1,090 1,060 1,025 995 960 930 900 6 930 93 45
Models
X
：
Regulation Space of Motor Pulley
(mm)
PD：Pitch Diameter of Motor Pulley
(mm)
Factory Set
Poin t
RPM / Turn**
X 17 18 19 20 21 22 23 24 X
RPM PD*
PD 112 109 106 103 99 96 93 90
RUA-NP5ATS
RPM 1,120 1,090 1,060 1,025 995 960 930 900 21.5 970 99 45
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)

6
REMOVING SHIPPING
WASHERS
5. REMOVING SHIPPING
WASHERS
Compressor is mounted on rubber isolators, and is held rigidly during shipment by two sets of shipping
washers. Before starting the compressor, remove the yellow-painted shipping washers, the compressor should
float freely on the rubber isolators.
Fig. 10. Removing Shipping Washers

7
T
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T
RUN
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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 W ork Check
List
INSTALLATION
W
ORK CHECK
L I ST
1. Is the unit solidly mounted and
leveled?
2. Is the installation location
adequa t e?
Space for Condenser Air
Flow
Space for Maintenance
Work
Noise and
Vibra t ion
Sunshine and
Rain f all
Appearance
3. Is the ducting work
adequa t e?
Filter
Soundproo f ing
Size and Length
I nsula t ion
4. Are the condensate drain lines properly
arranged?
Trap Drain
Di t ch
5. Is the electrical wiring system
adequa t e?
Wire Size Tightened
Connec t ions
Switch Size Operation Control
Devices
Fuse Size Safety
Devices
Voltage
Hz
6. Have the shipping washers been removed from the rubber-mounted
compressor?
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
posi t ion .
Pressure Gauges – Equip high and low
pressure
compound gauges according to Fig.
11 .
Thermostat – Set the thermostat at a
lower
temperature than the room
t empera t ure .
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
F
AN
posi t ion
and the system switch to the ON position,
and
the evaporator fan will start
immedia t ely .
Check the rotation direction, fan speed and
air
flow quantity through the
evapora t or .
2. Set the operation switch to the COOL
posi t ion ,
and the compressor and condenser fans will
start 3 minutes after this operation (refer to
Fig .
9) .
3. After system operation has become
s t abilized ,
check the suction and discharge pressures
on
the compound gauges. Normal
opera t ing
pressures are shown in Fig.
10 .
4. Check the operating voltage, phase balance
and operating
curren t.
5. Check to ensure that the thermostat
f unc t ions
properly .
6. Check to ensure that the control and
pro t ec t ive
devices function properly (refer to Table
3) .

T
ES
T
RUN
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8
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
 Standard Ventilation and Cooling Operation
Fig. 9. Standard Operation Sequence
* : Thermostat ON denotes that it is calling for the cooling operation
** : ORIF is a manual resetting device, and the other are automatic resetting safety devices.

Table 3. Safety and Control Device Setting
Model RUA-NP5ATS RUA-NP8ATS RUA-NP10ATS RUA-NP15ATS
For Compressor E505DH E855DH E505DH E855DH
High Pressure Switch Automatic Reset, Non-Adjustable
Cut-Out MPa 4.15 4.15 4.15 4.15
kg/cm
2
G 42.3 42.3 42.3 42.3
Cut-In MPa 3.2 3.2 3.2 3.2
Non-Adjustable
(built-in PCB)
No. 1 min 3 3 3 3
No. 2 min --- --- --- ---
For Evaporator Fan Motor
Overcurrent Relay A 2.6 3.6 6.0 9.0
For Condenser Fan Motor
Internal Thermostat Automatic Reset, Non-Adjustable
Cut-Out °C 160 160 160 160
Cut-In °C 130 130 130 130
For Control Circuit Fuse
Capacity A 2.5 2.5 2.5 2.5
6.5 Safety and Control Device Setting
9
TEST RUNNING
kg/cm
2
G 32.6 32.6 32.6 32.6
Overcurrent Relay Automatic Reset, Non-Adjustable
230V, 60Hz A 21 36 25 39
Internal Thermostat Automatic Reset, Non-Adjustable
Cut-Out °C 130 130 130 130
Cut-In °C 108 108 108 108
CCP Timer for Compressor

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10
▲
！CAUTION
● R410A is non-azeotrope
re f rigeran t.
Therefore, when the refrigerant
leaks ,
its component’s weight percentage
will
change. Instead of
recharging
refrigerant, we should process
t he
system all over
again .
● When charging R410A refrigerant,
be
sure the refrigerant being charged is
in
its liquid
s t a t e .
● Too much or insufficient charging
o f
refrigerant will lead to
compressor
f ailure .
● Keep the refrigerant charging error
a t
about ±
0.1 kg .
7.
MAINTENANCE
The unit should be periodically
inspec t ed
according
to the same items as those described
in
the
paragraph entitled "Test Running". In order
t o
ensure dependable operation and long life,
t he
following additional items should be
given
particular
a tt en t ion .
Components
Compressor – No maintenance work is
required
for hermetic compressors, if the cycle
remains
sealed .
Air-Cooled Condenser – Inspect the
condenser
and remove any accumulated dirt from the coil
a t
regular intervals. Other obstacles such as
growing
grass and pieces of paper, which might
res t ric t
airflow, should also be
removed .
Electrical Equipment – Always pay
care f ul
attention
to working voltage, amperage and
phase
balance.
Check for faulty contact caused
by
loosened
terminal connections, oxidized
con t ac t s ,
foreign
matter, and
o t hers .
Control and Protective Devices – Do
no t
readjust
the setting in the field unless the setting
is
maintained at a point other than the point listed
in
Table
3 .
Field-Supplied Filter – Inspect for
accumulated
dirt
on the filter. Exchange or clean the filter
i f
required.
The inspection interval may
be
determined by the
operating conditions for
each
installation
si t e .
Condensate Drain Pan and Drain Line –
I nspec t
and/or clean the condensate drain line at
leas t
twice
a
year .
Evaporator Fan – Check for a loosened fan
bel t
and abnormal
sounds .
Lubrication
Compressor – The compressors are charged
a t
the factory with the correct oil listed in
" Componen t
Detailed Data" in Technical Catalog Ⅰ and the
compressor nameplate. It is not necessary to
add
oil, if the cycle remains
sealed .
Fan Motors and Bearings – All fan motors
and
the evaporator fan shaft bearings
are
pre-lubricated.
Lubrication is not
required .
Refrigerant Cycle
Strainer – Check for clogging after the
t ime
when
the cycle is
opened .
Refrigerant Re-Charge – This unit has
been
charged with refrigerant.
W
hen the
cycle
requires re-charging due to leakage
or
replacement of parts, follow the
procedures
given
below (refer to
Fig . 11) .
1. Conduct vacuuming from the check joint
on
both the high pressure pipe and the
low
pressure pipe for 1 to 2 hours until
t he
pressure gage reads –0.1Mpa. Turn off
t he
vacuum pump and wait for 5 minutes.
Make
sure the pressure no longer
rises .
2. Connect a charging cylinder to the check
join t
and charge refrigerant slowly in the cycle
by
weighing the charging cylinder.
Proper
refrigerant charge is specified on the
uni t
nameplate (The error of charging volume
mus t
be kept within ±0.1
kg) .
3. Be sure to conduct the leakage
de t ec t ion work .

M
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11
Model
Compressor
Model
Operating
Charge
RUA-NP5ATS E505DH
RUA-NP8ATS E855DH
RUA-NP10ATS E505DH
Refrigerant R410A
(kg)
Compressor
Removal
When removing the
compressor ,
Fig. 11. Refrigerant
Re-Charge
8. WINTER
SHUTDOWN
Winter
shutdown
1. Shut OFF the power supply to the
unit.
2. Remove all wiring connections and
piping
connections to the
compressor.
3. Remove the washers on the
compressor
seat fastened on the
base .
4. Slightly lift the compressor, and pull
ou t
the compressor from the
uni t.
Spring
Start-Up
After any extended shutdown period, prepare
t he
unit
for operation as
f ollows :
1. Thoroughly inspect and clean the
uni t.
2. Clean or replace the air
f il t ers .
3. Clean the condensate drain
lines .
4. Remove any accumulated dirt from the
condenser
and the evaporator
coil .
5. Check the fan balance and attempt to operate
t he
f an .
6. Check the fan belt
t ension .
7. Tighten all wiring connections and access
panels .
9. REPLACEMENT OF
PARTS
Replacement of parts should be performed by
ordering from the HITACHI Parts List. The Form A
HITACHI Recommended Spare Parts List is advisable.
When replacement of parts becomes necessary,
prepare the parts shown in the Form A Parts List.
RUA-NP15ATS E855DH
When shutting down the unit for winter, clean
t he
inside and the outside of the cabinet and dry the
uni t,
especially the drain pan and the drain lines.
This
unit
shall be preferably covered during shutdown,
in
order
to protect it from dust and
environmental condi t ions .
4.8
5.1
2 x 3.1
2 x 3.1

M
A
I
N
T
E
N
A
NC
E
12
Table 4. Test Running and Maintenance
Record
MODEL: RUA- MFG. NO. COMPRESSOR MFG.
NO. :
CUSTOMER'S
N
AME AND ADDRESS:
DATE:
1. Is the rotation direction of the evaporator fan
correc t ?
2. Is the rotation direction of the condenser fan
correc t ?
3. Are there any abnormal
sounds?
4. Has the unit been operated at least twenty (20)
minu t es?
5. Check Room
Tempera t ures :
Inlet: DB ℃,W B
℃
Outlet: DB ℃,W B
℃
6. Check ambient
Tempera t ures :
Inlet: DB ℃,W B
℃
Outlet: DB ℃,W B
℃
7. Check suction line Temperature and
superhea t:
Suction line Temperature:
℃ ,
Superheat:
℃ ,
8. Check
Pressures :
Discharge Pressure:
kg / cm
2
G
Suction Pressure :
kg / cm
2
G
9. Check
Vol t age :
Rated Voltage:
V
Operation Voltage: R-S V,S-T V,T-R
V
Starting Voltage:
V ,
Phase Imbalance: 1 – V/V
m
=
10. Check Compressor input and running
curren t:
Input:
kW
Running Current:
A
11. Do the control devices function
properly?
12. Do the protective devices function
correc t ly?
13. Is the refrigerant charge
adequa t e?
14. Are the drain lines draining
f reely?
15. Are the air filters
clean?
16. Are the evaporator coil and condenser tubes
clean?
17. Are all cabinet panels
f ixed?
18. Are all cabinet panels free from
ra tt ling?
19. Has the unit been checked for refrigerant
leakage?
20. Is the unit clean inside and
ou t side?

TROUBLESHOOTING
10. TROUBLESHOOTING
Troubleshooting Charts
The following charts show efficient checking procedures for trouble.
：Fault ：Check ：Cause No Brackets：Remedy
No Cooling
-------------------------------Obtain the Correct Voltage
-------------------------------Repair the Power Line
-------------------------------Repair or Replace the
Components
-------------------------------Tighten the Connections
-------------------------------Obtain the Correct Voltage
-------------------------------Check the Power Supply
to the Motor：
Repair When Required
-------------------------------Replace the Bearing
-------------------------------Adjust Belt Tension
-------------------------------Check Fan Speed and the
Ducting System
-------------------------------Replace the Contactor
-------------------------------Repair the Contacts
-------------------------------Repair or Replace the Switch
-------------------------------Obtain Correct Voltage
-------------------------------Check the Power Supply
to the Motor：
Repair When Required
-------------------------------Repair or Replace if Required
-------------------------------Replace the Contactor
-------------------------------Repair the Contacts
-------------------------------Replace the Compressor
------------------------------------ Correct the Wiring
No Voltage or Low Voltage
Single-Phase
Shorted Components
Loose Connections
High Voltage or Low Voltage
Single-Phase or Phase Imbalance
Faulty Fan Bearing
Excessive Fan Belt Tension
Excessive Fan Load
Burned Coil
Faulty Contact
Defective Operation Switch
High Voltage or Low Voltage
Single-Phase or Phase Imbalance
Burned Coil
Faulty Contact
Other Faulty Electrical Components
Open Compressor Windings
Incorrect Wiring
Faulty
Unit Power Supply
Blown
Fuses for Operation
Circuit
Tripped
Overcurrent Relay
for
Evaporator
Fan
Tripped
Evaporator Fan
Motor
C
ontactor
Faulty
Internal Thermostat
for
Condenser
Fan
Compressor
Contactor
Evaporator
Fan Motor
Stopped
Operating
Condenser
Fan Motor
Stopped
Operating
No Cooling (Compressor Does Not Start)
Faulty
13

TROUBLESHOOTING
Insufficient Cooling
---------------------See ”High Discharge Pressure” or
”Low Suction Pressure”
---------------------Repair the Clogging and
Replace the Switch if Required
---------------------Repair or Replace if required
---------------------Obtain Correct Voltage
---------------------Check the Power Line to the
Compressor: Repair when Required
---------------------See ”High Discharge Pressure”
and ”High Suction Pressure”
---------------------Tighten the Connections
---------------------See ”High Suction Pressure”
---------------------See ”High Discharge Pressure” or
”Low Suction Pressure”
High Discharge Pressure
----------------------- Clean the Condenser
----------------------- Check the Voltage and Obtain Correct Voltage
----------------------- Repair or Replace the Motor
----------------------- Secure Space for the Required Air Flow
----------------------- Charge the Correct Refrigerant Quantity
----------------------- Purge the Gas
----------------------- Remove the Restriction
----------------------- See ”High Suction Pressure”
Low Discharge Pressure
----------------------- Add Refrigerant
----------------------- See ”Unit Working Range”
Operating
High Discharge Pressure or
Low Suction Pressure
Clogged Capillary of Pressure Switch
High or Low
Pressure Switch
Tripped
Overcurrent Relay
for
Compressor
Compressor
Cycling
Insufficient Cooling
High Discharge Pressure and
High Suction Pressure
Loose Connections
High Suction Pressure
High Discharge Pressure or
Low Suction Pressure
Tripped
High Voltage or Low Voltage
Single Phase or Phase Imbalance
Cycling ON
Faulty Switch
Condenser
Air Flow
High Discharge Pressure
Restricted
Clogged Condenser Coil
Low Fan Speed
Faulty Fan Motor
Circulating Air Flow
Overcharged Refrigerant
Non-Condensable Gas
Restricted Liquid Line
High Suction Pressure
Condenser Air
Inlet Temperature High
Condenser
Air Flow
Low Discharge Pressure
Low Refrigerant Charge
Low Ambient Temperature
14

Compressor
Noisy Operation
Low Suction Pressure
Worn Compressor Parts
Knocking Runner
Worn Bearing
Loose Fan Belt
Partially Clogged
Refrigerant Short Charge
Loose Fixed Screw
Weak Foundation Installation
Liquid Line Whistling
Inadequate Duct Work
Evaporator Fan
Noisy
Unremoved Shipping Washers
Overcharged Refrigerant
Shipping Washers
Noisy
Strainer
Liquid Refrigerant
Backing Up
TROUBLESHOOTING
High Suction Pressure
-----------------------------Reduce the Fresh Air Intake
-----------------------------Reinforce the Duct Insulation
-----------------------------Replace or Repair the Compressor
-----------------------------Charge Correct Refrigerant Quantity
-----------------------------See ”High Discharge Pressure”
Low Suction Pressure
-----------------------------Clean the Air Filter
-----------------------------Adjust the Belt Tension
-----------------------------Remove the Restriction
-----------------------------Adjust the Fan Speed
-----------------------------Repair or Replace the Motor
-----------------------------Remove Obstacles to Air Circulation
-----------------------------Repair or Replace if Required
-----------------------------Remove the Restriction
-----------------------------Add Refrigerant
-----------------------------See ”Low Discharge Pressure”
Noisy Operation
------- Remove the Washers
-------Charge the Correct Refrigerant Quantity
-------See ”Low Suction Pressure”
-------Replace or Repair the Compressor
-------Fix the Runner or Casing Properly
------- Replace the Bearing
------- Adjust Fan Belt Tension
------- Clean the Strainer
------- Add Refrigerant
------- Tighten All Fixed Screws
------- See the Installation Guide
-------Clean the Flexible Ducts
Evaporator
Air Flow
Low Suction Pressure
Restricted
Clogged Air Filter
Slipping Fan Belt
Restricted Duct
Low Fan Speed
Faulty Fan Motor
Short Cycling
Faulty Thermostat
Restricted Liquid Line and Suction Line
Low Refrigerant Charge
Evaporator Air
Inlet Temperature
Low
Low Discharge Pressure
Evaporator Air
Inlet Temperature
High Suction Pressure
High Excessive Fresh Air Intake
Insufficient Duct Insulation
Defective Compressor Valve
Overcharged Refrigerant
High Discharge Pressure
15

65M P 3212
Printed in the Philippines