7.installation,operation & maintenance(iom)
TRANSCRIPT
-
7/24/2019 7.Installation,Operation & Maintenance(IOM)
1/65
Installation,Operation&Maintenanceanual
PACV-S
Packaged Air Conditioners
-
7/24/2019 7.Installation,Operation & Maintenance(IOM)
2/65 2 |2 |
Table of Contents1 Introduction 4
Nomenclature . . . . . . . . . . . . . . . . . . . . 5
Safety Instructions . . . . . . . . . . . . . . . . . . 5Specic Hazards. . . . . . . . . . . . . . . . . . . . 5
Points To Remember. . . . . . . . . . . . . . . . . . 6
Component Features . . . . . . . . . . . . . . . . . 7
Liquid Line Controls . . . . . . . . . . . . . . . . . . 9
Electrical Control panel . . . . . . . . . . . . . . . 10
Room Unit . . . . . . . . . . . . . . . . . . . . . 11
2 Installation
Receiving of Equipment . . . . . . . . . . . . . . . 13
Rigging . . . . . . . . . . . . . . . . . . . . . . 13
Handling . . . . . . . . . . . . . . . . . . . . . . 13
Storage . . . . . . . . . . . . . . . . . . . . . . 14
Location & Space Requirements . . . . . . . . . . . 14
Pre-Installation Checkup. . . . . . . . . . . . . . . 15
Preparation For Installation . . . . . . . . . . . . . 16
Carrying Out Installation . . . . . . . . . . . . . . . 16
Condensate Draining . . . . . . . . . . . . . . . . 16
3 Operation
Pre-Startup Checklist . . . . . . . . . . . . . . . . 17
Pre-Startup Procedure . . . . . . . . . . . . . . . . 17
Service Record . . . . . . . . . . . . . . . . . . . 18
Unit Startup . . . . . . . . . . . . . . . . . . . . 19
Display & Keypad Operation . . . . . . . . . . . . . 20
Alarms . . . . . . . . . . . . . . . . . . . . . . . 21
List of alarms in the unit controller . . . . . . . . . . 21
Operation of the Room Unit . . . . . . . . . . . . . 22
Setting the address of the room unit . . . . . . . . . 22
switching in and switching off the unit . . . . . . . . 22
Commissioning Test Report . . . . . . . . . . . . . 25
4 Maintenance
Periodic Maintenance . . . . . . . . . . . . . . . . 26
Leak Testing, Evacuation &
Charging Procedures . . . . . . . . . . . . . . . . 28
Fan . . . . . . . . . . . . . . . . . . . . . . . . 32
-
7/24/2019 7.Installation,Operation & Maintenance(IOM)
3/65 | 3
Bearing . . . . . . . . . . . . . . . . . . . . . . 32
Fan Belt Adjustment. . . . . . . . . . . . . . . . . 33
Fan Pulley Adjustment
(For variable pitch pulleys only) . . . . . . . . . . . 35
Alignment of Shafts & Sheaves . . . . . . . . . . . . 35
Mold In And Around Drain Pans . . . . . . . . . . . . 36
Coil . . . . . . . . . . . . . . . . . . . . . . . . 37
Coil Cleaning . . . . . . . . . . . . . . . . . . . . 37
Compressor Oil . . . . . . . . . . . . . . . . . . . 37
Adding Oil . . . . . . . . . . . . . . . . . . . . . 37
Dismantling & Disposal . . . . . . . . . . . . . . . 38
Expansion valve service & maintenance . . . . . . . . 38
Hot gas by pass . . . . . . . . . . . . . . . . . . . 40
Refrigerant Recovery, Recycling &
Reclamation . . . . . . . . . . . . . . . . . . . . 43
Trouble Shooting . . . . . . . . . . . . . . . . . . 46
5 Appendix
Appendix I . . . . . . . . . . . . . . . . . . . . . 49
Loading Points . . . . . . . . . . . . . . . . . 49
Appendix II . . . . . . . . . . . . . . . . . . . . . 51
Dimensional Data . . . . . . . . . . . . . . . . 51
Appendix III . . . . . . . . . . . . . . . . . . . . 55
Refrigerant Piping Layout . . . . . . . . . . . . 55
Appendix V . . . . . . . . . . . . . . . . . . . . . 57
Filter Dimension . . . . . . . . . . . . . . . . 57
Appendix IV . . . . . . . . . . . . . . . . . . . . 58
Spare parts . . . . . . . . . . . . . . . . . . . 58
Appendix VII . . . . . . . . . . . . . . . . . . . . 57
Typical wiring diagram . . . . . . . . . . . . . . 57
Appendix VIII . . . . . . . . . . . . . . . . . . . . 62
Typical Wiring Diagram . . . . . . . . . . . . . 62
Appendix IX . . . . . . . . . . . . . . . . . . . . 63
Instructions For Downloading/Upgrading The
Software For Microprocessor . . . . . . . . . . . 63
Appendix X . . . . . . . . . . . . . . . . . . . . . 64
P-T Chart . . . . . . . . . . . . . . . . . . . . 64
-
7/24/2019 7.Installation,Operation & Maintenance(IOM)
4/65 4 |
INSTALLATION, OPERATION & MAINTENANCE
This manual must be carefully read and followed in
order to avoid unnecessary/dangerous conditions in the
machine and to guarantee the safety of the equipment.
The contents in this manual are mainly the installation and
operating instructions of your Package Air Conditioning
unit. The precautions mentioned through out this manualshould be taken seriously to derive maximum safety forall. Installation, service and start up of any air-conditioning
equipment should be done only by a qualified personnel or
service technician. Always observe precautions in the manual
and be familiar of all the symbols / labels attached in the unit
when dealing or working with the equipment.
Unit DescriptionThe PACV-Sseries is a modern, diversified and environment
friendly series of packaged air conditioners which use R - 134a
as the refrigerant.
The complete PACV-Spackage provides an extremely rugged,
heavy duty, long-life, energy efficient and self-contained package
air conditioner that will provide cooling at higher efficiency overa long and extended life. What makes PACV-Sseries the prideof SKM products is the use of :
The SKM PACV-S series packaged air
conditioning units are durable, dependable,
strong, reliable, versatile, quiet and energy
efficient. Wherever a heavy duty packaged
air-conditioner is required, the PACV-Sseriesshould be an automatic choice.
Unit Name PlateTypical SKM Air Cooled Packaged Unit
nameplate is as shown.Check the nameplate data with the P.O/
Submittal when receiving the unit.
For the representation and understanding of the points
of caution, attention, danger, and information. Following
symbols are used throughout the manual.
Note:- It is not the intention of this manual
to cover all possible variations in systems
that may occur or to provide comprehensive
information concerning every possible
contingence that may be encountered during an installation,
operation and maintenance. If additional infor mation isrequired or if specific problems arise that are not fully
discussed in this manual, contact your local office.
Always heed all WARNING and SAFETY
INSTRUCTION boxes. Always read and heed all
instructions in this manual carefully. Failure to
follow WARNING, SAFETY INSTRUCTIONS and all
other instructions could result in severe personal
injuries and death.
Introduction
General Warning
CAUTION
General Information .
INFORMATION
Take special attention
and po in ts to be
noted.ATTENTION
Indicates dangers
through electricalshock, system
pressure, and
location.DANGER
Indicates dangers by
high voltage
HIGH VOLTAGE
Indicates dangers
by moving/rotating
parts
MOVING/ROTATING PARTS
HOT PIPES
Indicates dangers by
hot pipes
MODEL
Qty KW FLA
Qty KW FLA
MANUFACTURING SERIAL NO
MANUFACTURED IN SHARJAH,UNITED ARAB EMIRATES
HEATER KW/NO. OF STAGES
R-134A CHARGE(KGS)
CONDENSER MOTOR
EVAPORATOR MOTOR
MIN.CIR AMPS/MAX. FUSE AMPS
COMPRESSOR MODEL Qty LRA RLA
POWER SUPPLY (V/Ph/Hz)
CONTROL VOLTAGE(V/Ph/Hz)
Factory/Field
ITEM CODE
High efficiency totally sealed hermetic scrollcompressor.
Totally enclosed, Class F insulated, IP55
protected condenser and evaporator fan
motors.
Heavy duty condenser and evaporator coils
optimised in design for long-life maintenance
free operation.
Cabinet construction specifically designedfor Gulf climates.
IP 54 Electrical panel.
Factory installed, advanced and user friendlymicroprocessor based control system.
Interface capability with major BMS protocols
(option).
-
7/24/2019 7.Installation,Operation & Maintenance(IOM)
5/65 | 5
INSTALLATION, OPERATION & MAINTENANCE
SKM reserves the right tochange, in part
or in whole the specifi cations of its Air
Conditioning Equipment at any time in
order to add the latest technology. Therefore,the enclosed information may change without
any prior notice.
Nomenclature
Safety Instructions
Carefully read the content of this
manual before installing the air
conditioning equipment. For maximumsafety installers should always follow
the list of warnings. During the
installation process care should be
taken to avoid any accidents related to:
1. High voltage
2. High pressure in the system
3. Hot pipes due to discharge
temperature
4. Moving/Rotating parts
This manual explains how to install,
operate and maintain SKM PACV-S
series,Air coo led packaged unit . The
manufacturer shall not be responsible
for damages arising from wrong
practices used. So SKM recommendsto do the installation including the
connection of electricity, operation and maintenance
by a person qualified for the air- conditioning and
refrigeration work only.
The manufacturer shall not be responsible for
damages originating from unauthorized changes
or the improper connection of electricity and not
adhering to the operation limits included in the
manual. Also this shall invalidate the warranty.
The air conditioning equipment should be used
only for the applications for which it has been
designed.
Refer product name plate, wiring diagrams and catalogues
for the electrical characteristic, of the equipment to selectcorrect wire sizes and isolators prior to the insulation.
It is the responsibility of the user or the person installing
the equipment to provide proper grounding and branch
circuit protection according to NEC, Local & National
safety regulations.
This Air Conditioning equipment must be disconnected
from the mains if any repair work is to be carried out.
Do not use the units if damaged. If problems occur, switch
the unit off and disconnect it from the power supply.
The control ON/OFF switch in the control panel does not
disconnect the equipment from the mains and thus it is
not to be used as a safety switch.
Do not attempt to repair, move, alter or reinstall the unit. If
performed by an unauthorized personal, these operations
may cause electrical shock or fires.
Always remember to inspect the units, refrigerant tubes
and protection regularly. These operations should beperformed by a qualified personnel only.
Contact SKM After sales in case any technical support
is required.
PAC V - 5 1 008 S Y
Packaged Air
Conditioner
V-shaped condenser
construction
Power supply frequency
5 = 50 Hz
6 = 60 Hz
Power Supply CodeY: 380-415V/3Ph/50Hz
P: 440V/3Ph/50HzR: 380V/3Ph/60Hz
E: 460V/3Ph/60HzT: 220V/3Ph/60Hz
Scroll Compressor
(R-134a)Nominal
Capacity (TR)
No. of Refrigerant
Circuits
Specific Hazards
Do not stand or work under suspended loads.
Wear a hard hat, safety shoes and gloves.
Noise Emission
The sound emission expected in normal use of the fan
should be duly taken into account.
Wear ear defenders when
working near to or on the running
fan!
Rotating Shafts and Impellers
Objects fixed to rotating shafts and impellers can fly
off at an angle and cause serious injury.
Articles of clothing and hair can get caught in rotating
shafts and impellers.
Heavy Loads
The heavy weight of fans
and their components entail
the following risks during
maintenance:
Risk of being trapped,
crushed or cut by moving or toppling
machinery.
Danger of falling components.
-
7/24/2019 7.Installation,Operation & Maintenance(IOM)
6/65 6 |
INSTALLATION, OPERATION & MAINTENANCE
Being an electromechanical machine, the unit may fail or
cause difficulties. Remembering the following few points will
ensure correct and prompt rectification and continued optimal
performance.
Points To Remember
A correct installation ensuring proper clearances forcorrect condenser air flow and maintenance as per the
drawings shown for recommended clearances
Proper level base on foundation with appropriatevibration mount. All connections and hook up to be
followed as per instructions, which ensures long term trouble
free operation and performance.
If power fuse is blown off, be sure to replace the same
with a new fuse having pre designed Amperage. Donot use a steel wire or copper wire instead of proper
fuse. Genuine fuse ensures safety and proper protection.
Incorrect fusing may cause fire or trouble with your equipment.
Before replacing any fuse or opening any electrical
panel door, make sure the main switch is OFF.
Do not spray or sprinkle water directly over or into
the air conditioning equipment for cleaning becauseelectric insulations and terminal of the components
are opened.
Following a power supply interruption during operation,
the microprocessor is programmed to restart the unit
automatically when power supply has returned to normal.
Periodical maintenance of the unit will give better
performance in the long run than only break down
maintenance.
The microprocessor controller is programmed to stop
functioning the Air conditioning equipment includingthe compressor in the event of a safety device trips. The
problem should be investigated and repaired or rectified as per
trouble shooting instruction in this manual before attempting to
reset and restarting the machine.
This Air conditioning equipment is meant to be installedout doors and suitable to normal environment elements.
Do not try to cover or block any inlets or discharge openings
to condenser.
Insist on maintenance from a reputable maintenance
contractor to ensure a trouble free operation.
Do not remove guards
during operation.
Do not wear loose-fitting
clothing when working
near rotating shafts and
impellers.
Wear gogg les.
Hot Surfaces
There is a risk of sustaining burns or scalds
on hot surfaces during operation.
Do not touch the Motor,
Compressor bo dy, Discharge
line during operation.
When the condenser fan has
stopped wait until the motor
has cooled down.
Wear protecti ve gloves.
Electrical Shock Hazards
All p ower must
be disconnected
prior to installation
and servicing this
equipment. More
than one source of
power may be present. Disconnect
all power sources to avoid
electrocution or shock injuries.
Avoid breathingfiber glass dust.
Use a NIOSH approved dust/mist respirator.
Avoid contact with the skin or eyes. Wear
long-sleeved, loose-fitting clothing, gloves,and eye protection.
Wash clothes separately from otherclothing: rinse washer thoroughly.
Operations such as sawing, blowing,tear-out, and spraying may generate
fibre concentrations requiring additional
respiratory protection. Use the appropriate
NIOSH approved respiration in these
situations.
Fiber glass Insulation!This Product contains fiber glass wool. Disturbing
the insulation in this product during installation,
maintenance or repair will expose you to airborne
particles of glass wool fibers and ceramic fibers.
All necessary Personal Protective Equipment
(PPE) including gloves, eye protection, mask,long sleeves and pants must be worn when
working with products containing fibreglass
wool. Exposition to glass wool fibers without
all necessary PPE equipment could result in
cancer, respiratory, skin or eye irritation, which
could result in death or serious injury.
-
7/24/2019 7.Installation,Operation & Maintenance(IOM)
7/65 | 7
INSTALLATION, OPERATION & MAINTENANCE
Compressor
Compressors used in PACV-S packaged unit series are
hermetically sealed, compact scroll with the following features:
Vacuum operation!Compressor damage!
Scroll compressors should never be
used to evacuate a refrigeration or
air-conditioning system.
Do not pump down the scroll
compressor into a vacuum!
Three phase compressors
only: On initial startup, if
the compressor sound isabnormally high and the readings
of suction and discharge pressures
are outside normal range, there is
a possibility that the compressor
rotation is in the reverse direction.
In this case, interchange any
two legs of the power supply
and attempt to restart. Running
a scroll compressor in reverse
direction for an extended period
of time will cause damage to the
compressor. such damage is not
covered under manufacturers
limited warranty.
Reverse rotation for 5 to
15 minutes will result in
the overheating of motor
windings. In thi s case, the thermostat
in the motor windings open and
result in stopping of the compressor.
Continued reverse operation of scroll
compressor will result in failure of scroll
compressors. Such failures are
Component Features
High Efficiency.
Quite operation, Low Sound levels.
Compact and light .
Limited wear.
70% fewer moving parts than comparably sized
reciprocating compressors
Unique ability to handle liquid refrigerant.
Suction gas motor cooling.
Centrifugal oil pumps with filter and magnet.
Brazed fittings or Rotalock as options.
Multiple refrigerant circuits on larger units provides
efficient part load.
Parallel Operation
A parallel compressors installation, with common suction line
and common discharge line, gives a reduced operating cost
through greater control of capacity and power consumption. This
is achieved by staggering compressor switch-on sequences that
allow the parallel system to match its power with the capacity
needed. By switching-off individual compressor from parallelinstallation, while other compressor is operating 100%, the
improved part load efficiency can be achieved. The specially
developed and adopted oil equalization system ensures correct
compressors operation, oil balancing between compressors and
reliability.
Condensers
Condenser coils are manufactured of seamless copper tubesmechanically bonded to aluminum
fins to ensure optimum heat transfer.
All coils are tested against leakage by
air pressure of 450 psig (3100 kPa)
under water. All standard coils are
2,3 or 4 rows/14 FPI, 3/8 (9.5 mm)
O.D. tubes. An integral subcooling
circuit is provided to increase the
cooling capacity, without additionaloperating cost.
For different application requirements,
other optional condenserfin materials
are available:
Copper fins. Electrotinned Copper Fins.
Copper finned coils with electro-tinned after manufacturing.
Precoated Aluminum fins
The pre-coated is hydrophobic polyurethane resin. This optionprovides substantial corrosion protection beyond standard
coil construction.
Aeris Guard Coil Coating
The Aeris Guard Coil is a self etching high performance
modified epoxy finish that is specifically designed to coat
and protect Aluminum and Copper surfaces. In addition, the
coating is ideal for the protection of ferrous and non ferrous
materials.
SKM PACV-Sseries, all models, are restricted to a 14FPI (1.8
mm) fin spacing condenser coil. Gulf dust storms and the general
level of available maintenance in Gulf countries ensures this
condenser coil design shall provide long life and maintenance
free operation with the least possibility operational blockage on
the condenser. Ample condenser surface and sensible air flow
across the condenser ensures a low temperature differentialbetween condensing temperature and the high Gulf ambients
making thePACV-Spackaged unit perform efficiently and durably.
NOT covered under the manufacturers limited
warranty.
-
7/24/2019 7.Installation,Operation & Maintenance(IOM)
8/65 8 |
INSTALLATION, OPERATION & MAINTENANCE
Condenser Fans
Condenser fans are
propeller type, aluminium
alloy blades, directly driven
by electric motors. Motors
are Totally Enclosed Air Over(TEAO) six pole with class F
insulation and minimum IP55
protection. The TEAO and class F insulation features ensurelong life and are unique for SKM.
The motors are factory wired, using wires specially selected forhigh ambients operation, to unit control panel where the motor
contactors are located to control the operation of these motors.
The condenser fans are individually statically and dynamically
balanced at the factory.
Complete fan assembly is provided with suitable acrylic coated
fan guard.
EvaporatorEvaporator coils are manufactured of seamless copper tubes
mechanically bonded to aluminium fins to ensure optimum
heat transfer. All evaporator coils are tested against leakage
by air pressure of 300 psig (2068 kPa) under water. The DXevaporator coils are complete with headers of seamless
copper tubing. Supply headers incorporate a correctly sized
distributor. For different application requirements, other
evaporator coil material and/or treatment are available
on request.
Evaporator coil supplied with suitable size
thermostatic expansion valve(s) and multi-
circuited distributors providing capacitymodulation to match the compressors. The cross
wave fins and staggered tubes design uses the
evaporator surface effectively by creating uniform
air turbulence and optimum heat transfer over the
entire finned surface. Requirements for higher
face velocities can be handled by use of moisture
eliminators to avoid carryover.
Copper fins.
Electrotinned Copper fins.
Copperfinned coils with electro-tinned after
manufacturing.
Precoated Aluminum fins.
The pre-coated is hydrophobic polyurethane
resin. This option provides substantial
corrosion protection beyond standard coil
construction.
Aeris Guard Coil Coating.
The Aeris Guard Coil is a self etching high
performance modified epoxy finish that is
specifically designed to coat and protect
Aluminum and Copper surfaces. In addition,
the coating is ideal for the protection of
ferrous and non ferrous materials.
Fan Section
Fans in the PACV-S units are selected for the best sound
characteristics based on maximum fan efficiency. More than one
arrangement of evaporator fans are used in the PACV-Sseries
packaged units due to the wide range of air flow rates.
Commonly, all fans are double inlet, double width, centrifugaltype with forward curved impellers provide the combination of
efficiency and quietness of operation. All fans are statically and
dynamically balanced, belt driven by motor sizes up to 15 kW are
provided with adjustable pitch pulleys as standard.
Above 15 kW motor sizes are equipped with fixed pitch pulleys
s standard and adjustable pitch pulleys are option. Specify PP.
Single fan is used for PACV-51008S, PACV-51010S, PACV-
61009S & PACV-61012S models. Models PACV-51014S~PACV-
52055S & PACV- 61018S~PACV- 62066S are equipped with twofans. These fans are mounted on a single heavy duty shaft driven
by a single electric motor. Shaft end insert into over sized, tapered
lock self aligning long life bearings. The motor is mounted on
an adjustable base, so that belt tension can be easily adjusted.
Models PACV-52065S and PACV-62076S onwards, use singlefan assembly, which has maximum strength, high performance,
quietness and reliability. These fans use self aligned ball or pillow
block bearings that are greased for life. Pillow block bearings
are provided with re-greasing fittings. The motor is mounted on
an adjustable base, so that belt tension can be easily adjusted.
The complete fan-motor drive assembly is mounted on a floating
sub-base. In order to limit transmission of noise and vibration,
the complete fan motor sub-base assembly is mounted on anti-
vibration mounts. Flexible connection is provided between fandischarge and casing panel to avoid transmission of vibration to
the connecting duct.
The optional modular construction units for models PACV-
51008S~PACV-52055S & PACV-61009S~62066S are also using
the same fan specifications as mentioned above.
The electric motors are foot mounted, 4 pole, totally enclosed fan
cooled (TEFC), IP-55 protected, Class F insulation with Class
B temperature rise.
Drive package is factory selected for the medium air flow rate as
shown in the capacity ratings. Alternative drive packages to meet
specific job or client requirements can be provided.
Refrigerant Circui t
PACV-S series comes complete, as standard, with correctly
sized and piped refrigerant lines including sight glass, filter drier,
thermostatic expansion valve, solenoid valve, shut-off valve, and
a full operating charge of R-134a in each circuit.
Piping is fabricated from ACR grade copper piping. Suction line isinsulated with (12 mm) wall thickness closed cell pipe insulation.
Filter Section
PACV-Sseries can be with a range of filter sections and filters
to meet requirements for the most demanding applications.
Flat or vee filter sections to accommodate 1 or 2
cleanable aluminium media filters can be provided.
A bag filter section to house 22, 30 or 36 deep
bag filters having efficiencies as desired can also
be provided, as required. Filter sections come with
latches to provide easy access for removal and formaintenance.
-
7/24/2019 7.Installation,Operation & Maintenance(IOM)
9/65 | 9
INSTALLATION, OPERATION & MAINTENANCE
Shut Off Valve/Ball Valve
Usually used so that portions of refrigeration system can be
isolated for service or repairs.
Sight glass
Used to observe the flow of liquid refrigerant. Bubbles or
foaming in the sight glass indicate a shortage of refrigerant or
restriction in the liquid line that can adversely affect system
operation. Sight glasses are widely used as a means of
determining if the system is adequately charged.
Filter Driers
Driers are mounted in the refrigerant liquid line to ensure that
all the refrigerant in circulation passes through the drier each
time it circulates through the system so as to remove any
moisture or foreign matter from the refrigerant stream.
To order a sand trap louvre from SKM specify fresh air opening
size with option ASL.
Casing/Structure
Designed for ease of handling and low cost to install. ThePACV-S
Air Cooled Packaged Units are factory assembled and mounted
on a rigid base. The unit casing used in PACV-SPackaged units
is made of zinc coated galvanized steel sheets conforming to
JIS-G 3302 and ASTM A653 which is phosphatized then bakedafter an electrostatic powder coat of approximately 60 microns.
This finish and coating pass a 1000 hours in 5 % salt spraytesting at 95F (35C) and 95% relative humidity as per ASTM
B117. The entire casing panels are designed to be leak proof
against rain and ensure rain cannot enter the PACV-Sseries
packaged air conditioner interior. Evaporator section sealed
by the use of vinyl gasketing material.
The evaporator section is insulated from all sides with black-
neoprene faced heavy density 1 thick fiber glass insulation
for models up to PACV-52055S & 62066S and 2 thick
fiber glass insulation for models PACV-52065S & 62076S
onwards. The insulation cum sound liner meets the fire
requirements of NFPA90A and is secured with mechanicalfasteners in addition to water resistant adhesive.
For applications requiring an inner skin in the evaporatorsection, option DSE provides 0.7 mm galvanized inner
skin. Suitable isolation to ensure no cold-bridges
and no condensation on the exterior of the unitsis provided. The condensate drain pan is heavily
insulated to ensure that condensation may not
occur. Stainless steel condensate drain pans are
available on request.
Liquid Line Controls
Thermostatic Expansion Valve
For controlling the flow of liquid refrigerant into
the evaporator, an orifice in the valve meters
the flow into the evaporator, the rate of being
modulated as required by needle type plunger
and seat, which varies the orifice opening.
On 100% fresh air applications an initial sand
trap louvre can effectively minimize entrance
of sand into the air stream. High efficiency mini pleat panel filters are
available as an alternative for bag filter where
space is limited. Filter sections come with
latches to provide easy access for removaland for maintenance.
Low Pressure Switch
This switch is fitted in the suction side of each refrigerant circuit
and is wired to the unit controller digital input. Its function is to
protect the compressors against low suction pressure. If therefrigerant circuit is On to meet the cooling demand and this
switch remains open for a specific time (low pressure alarm delayset point), then the unit controller will switch off that circuit and
generate Low suction pressure alarm.
Solenoid ValveIt is used to stop the flow of refrigerant within
the refrigeration system.
The valve is typically a normally-closed type of
valve so that it is closed when it is energized
-
7/24/2019 7.Installation,Operation & Maintenance(IOM)
10/65 10 |
INSTALLATION, OPERATION & MAINTENANCE
10 |
Electrical Control PanelThe unit mounted control panel enclosure is fabricated out of heavy
gauge sheet steel in phosphatized powder coated baked finish.
The enclosure conforms to IP54 as per guidelines in IEC 529. A
hinged access door and key-fastener is provided for easy access
and security. The panel is factory wired in accordance with NEC430 & 440, labelled, tagged and features 220V/240v controls.
All compressors are with DOL starting.
Individual compressor, condenser fan motors and evaporator
fan motor contactors.
Motor protector circuit breaker for condenser and evaporator
fan motors.
Control circuit breaker.
Control circuit on/off switch.
Microprocessor control boards.
Control Relays.
Power and control terminal blocks.
Microprocessor Controller
All PACV-Sseries package units are equipped with a full function
microprocessor based controller as a standard feature. Thecontroller is factory programmed for the control of evaporator
fan, compressors and condenser fans. The controller comes
with a built in keypad and display for simple but meaningful man
machine interface. This controller provides complete operational
control for the unit and has built-in auto diagnostic capability
that can signal normal operation or alarm conditions as well asshutting down the unit or system if necessary.
.The Main Features of the controller are as follows:
Built in LCD display with back light.
Roll & push knob and 3 function buttons.
Battery backed up built in real time clock.
Multiple authorization level to provide tight security
for the control system.
Capacity control based on room temperature or
return air temperature.
Alarm history.
A sleek & elegant design room unit.
Discharge Pressure Transducer
This transducer is fitted in the discharge side of
each refrigerant circuit and is wired to the analogueinput of the unit controller. Through this transducer,
the unit controller will monitor the discharge
pressure of the refrigerant circuits and cycle thecondenser fans (when compressors are running)
in order to maintain proper head pressure.
Facto ry se t t ings fo r p ressu re
switches and Fan cycling
Factory Switch Settings
DescriptionCut Out
(PSIG)
Cut In
(PSIG)
Low Pressure
Switch14.5 29
High PressureSwitch
300 200
Table 1
Factory Fan Cycling Settings
in Unit Controller
(Units with 4 fans)
Description On (PSIG) Off (PSIG)
Fan Cycling
Stage- 1180 130
Fan Cycling
Stage- 2200 150
Fan Cycling
Stage- 3220 170
Fan Cycling
Stage- 4240 190
Table 2
digital input. Its function is to protect the compressors
against high discharge pressure. If this switch
remains open for one second, then the unit controllerwill switch off the corresponding refrigerant circuit
and generate High Discharge pressure alarm.
High Pressure Switch
This switch is fitted in the discharge side of each
refrigerant circuit and is wired to the unit controller
-
7/24/2019 7.Installation,Operation & Maintenance(IOM)
11/65 | 11
INSTALLATION, OPERATION & MAINTENANCE
Display Information
SKM Pacvs series package units offer LCD
display which allows the operator to accessdifferent parameters of the unit. Operator can
view and change the unit parameters. The display
information includes: Status
Outputs
Inputs
Alarms
Set points
Password
System Protection
The intelligent microprocessor based controller
monitors all the safeties related to the unit and
makes the necessary protections,by shutting
down the entire unit or the effected circuit. Theprotection includes
Low suction pressure. High discharge pressure.
High compressor motor temperature. (For
compressors with internal motor protector).
Compressor short cycling.
Evaporator fan motor overload
BMS Connectivi ty (Optional)
Volt free contacts for run status, common fault
status, auto mode status and provision for remote
on/off shall be provided as option if required.
In addition, the PACVS microprocessor can
support the major BMS protocols such as BACnet,
Modbus & LON. Extra hardware may be required
depending on the protocol.
Room UnitThe controller comes with a loose supplied sleek
and elegant design room unit for installing in the
conditioned space. Communication between
unit controller and room unit is through two
wire interface. The communication cable
should be 2 core, twisted pair, unscreened
with stranded conductors, as per KNX
specification. Maximum distance between room
unit and controller can be 700 meters. The room
unit has a built in sensor for measuring the room
temperature. It transmits room temperature,
set point, unit operating mode etc. to the unitcontroller. Control of the compressors is based
on room temperature and the set point, as
standard. If unit control needs to be based
on duct temperature, please specify during
time of order.
Room unit display (Operator Controls)
ON/OFFButton for unit power on or unit
power off
Program
Button for Time scheduler, pressing
this button allows date/time setting,while holding it allows schedule
programming
Minus
Button for set-point adjustment,
each operation of the Minus (-)
button reduces the set point by
differential which is defined in
controllers setting
Plus
Button for set-point adjustment,
each operation of the Plus (+)
button increases the set point by
differential which is defined in
controllers setting
OK
Button for confirmation of date/time
and scheduler settings. Long pressof this button can toggle between
measurement units -oC and oF
FanButton for fan mode either
continuous mode or auto mode
Mode
Button for unit mode: Cool, heat,
ventilation and or cool-heat
auto changeover (*Cool-Heat
is available only if heat mode is
applicable)
Control or data communication
cables should not be routed alongwith power cables. Sufficient distance
is to be maintained while routing the cables
between Power and data communication cables
(If any).
Room Unit Installation
Installation must be carried with unit
power off.
Table 3
A brief description of each button in the room unit is shown in
table below:
-
7/24/2019 7.Installation,Operation & Maintenance(IOM)
12/65 12 |12 |
Figure 1
Figure 2
Step Two: Remove back cover
Open the back cover of the room unit as shown
using a screwdriver.
Step Three: Back plate Wiring
Install wiring into terminal blocks as indicated,
and push slack wire back into wall or junction box.
The communication cable between
room unit and microprocessor
controller should be 2 core, twisted pair,
unscreened with stranded conductors (As per
KNX Specification). Maximum distance between
room uni t and con troller can be 700 meters.
Step Four: Cover Installation
Install cover plate as shown. Cover plate may be removed using
a screwdriver as needed to access the terminals for wiring.
The room unit is not protected against
accidental connection to AC 230 V
The microprocessor controller & room
unit include electrical and electronic
components and must not be disposed
off as domestic waste. Current local laws on
disposal of electronic waste are to be observed.
INSTALLATION, OPERATION & MAINTENANCE
Step One: Location and Mounting
Select a mounting location with good air circulation away
from ventilation inlets, doors, windows, or other fresh air entry
points or near direct heat sources. For room installation, the
room unit should be mounted at least 4-1/2 feet above thefloor. Avoid direct sunlight and draught. Admissible ambient
conditions are to be observed.The room unit is designed for semi-flush surface mounting
with recessed conduit box. Cable entry is through the rear of
the unit. The unit comprises front housing and rear housing.
These can be locked together and released by snap
mechanism. Both the housings are plastic. Use the backplate as a template for locating holes for screws and wiring.
Mount the back plate using screws provided. Wall anchors
are recommended for drywall installations.
-
7/24/2019 7.Installation,Operation & Maintenance(IOM)
13/65 | 13
INSTALLATION,
Use all lift ing point s. Improper lifting can
cause severe personal injury and property
damage.
a. Support the unit well along the length of the base rail
b. Level the unit (no twists uneven ground surface)
c. Provide proper draining around the unit to prevent
flooding of the equipment
d. Provide adequate protection from vandalism,
mechanical contact, etc.
e. Securely close the doors
f. Cover the supply and return air openings an limits
without isolation dampers.
Rigging holes are provided on the sides of the unit.
Avoid twisting or uneven lifting of the unit
The cable length from bracket to the hook should always
be longer than the distance between the outer lifting points.
If the unit is stored at the construction site for an intermediateperiod, follow these additional precautions:
HandlingReceiving of Equipment
Responsibility should be assigned to a
dependable individual at the job site to
receive material. Eachshipment should be
carefully checked against the bill oflading. The shipping receipt should
not be signed until all items listed on
the bill of lading have been accounted
for.
When uncrating, care should
be taken to prevent damage.Heavy equipment should be
left on its shipping base until it has been
moved to the final location.
Check carefully for concealed damage. Any
shortage or damages should be reported to the
delivering carrier. Damaged material becomes thedelivering carrier s responsibility, and should not be
returned to the manufacturer unless prior approval is given
to do so.
The packing list included with each shipment
should be carefully checked to determine if
all parts and equipment have been received.Any accessories such as starters, contactors
or controls should be fastened to the basic unit to avoid
loss and prevent possible interchanging with other
units.
Make sure that wiring diagrams and
IOM manuals are available within theequipment control panel.
Rigging
Regardless of the packaging
used in transporting of the units, it
should preferably be lifted with a fork
lift truck or a crane and belts. The
units should be unpacked as close
as possible to its final installation position. The
unit should always be left standing upright.
Before positioning the unit, it is advisable tore-check the weights.
Remove the wooden pallet from underneath
the machine before installation
Use protectors to prevent sling or cable as
per Figure 3-4.
All protection/spreader bars shown in the
rigging illustration should be provided by the
customer on site.
WOODEN PIECE
HOOK
SLING
SHACKLE
WOODEN PIECE
SPREADER
SHACKLE
4No.EQUAL SLING
HOOK
Figure 3
Figure 4
-
7/24/2019 7.Installation,Operation & Maintenance(IOM)
14/65 14 |
INSTALLATION,
Storage Single Unit Installation
Table 4
Location and Space Requirements
When thePACV-Sunits need to be stored in a prolonged
period prior to installation, the following protective
measures are required: Units must be stored in a protected area and
safe from construction debris. Do not remove thewooden coil guard.
Check the pressure in high pressure side of
refrigerant circuit to confirm that the refrigerant
charge is intact in every three months. Take note
of the ambient while checking. Contact SKM After
Sales Office or SKM sales representative.
Keep the liquid line Shut Off valve closed.
When selecting a location for the unit, the following
points should be considered:
There should be enough space for air movement
beside the condenser coils which should beapproximately equal to the height of the coils.
The discharged air from the condenser fan should
not be obstructed by any roofing, ducting etc whichcould cause air short circuiting.
There should be sufficient area provided to enable
for the servicing of the unit.
The schematic shown in Figures 5-9 gives the
recommended clearance areas around the unit for
both maintenance and air flow.
A B C
51008-S 61009-S
51010-S 61012-S
51014-S 61018-S52015-S 62018-S
51017-S 61020-S
52017-S 62020-S
52020-S 62024-S
52023-S 62028-S 54
52026-S 62033-S
52030-S 62036-S
52032-S 62037-S
52038-S 62046-S
52045-S 62055-S
52050-S 62060-S
52055-S 62066-S 86
52065-S 62076-S 78
53070-S 63085-S53075-S 63090-S
53080-S 63095-S
53085-S 63100-S 108
53090-S 63105-S 114
53095-S 63110-S 121
54100-S 64120-S 124
54110-S 64130-S 128
54115-S 64136-S 134
54125-S 64145-S 142
ALL DIMENSIONS ARE IN INCHES
72
78
72
82
66
96
104
78108
PACV-S
50
52
-84
6066
SPACING FOR SERVICE
DUCT
A
B
A
PACV- 51008 S TO 52055 S
PACV- 61009 S TO 62066 S
Figure 5
SPACING FOR AIR FLOW
[1981]78
A
A
PACV- 62076 SPACV- 52065 S
DUCT
B
DUCT
Figure 6
[1165]46
A*
B
A
*
PACV- 63085 S TO 64145 S
PACV- 53070 S TO 54125 S
DUCT
DUCT
SPACING FOR BOTH AIR FLOW AND SERVICE*
Figure 7
Figure 8
DUCT
C
DUCT
B
SPACING FOR SERVICE SPACINGFOR AIR FLOW
PACV- 61009 S TO 62066S
PACV- 51008 S TO 52055S
Multiple Unit Installation
-
7/24/2019 7.Installation,Operation & Maintenance(IOM)
15/65 | 15
INSTALLATION,
Multiple Units Installation (Modular
Construction)
t.
Recommendations
It is a necessity that the units are installed with adequate
free space around them to ensure proper circulation ofair that is rejected by the condensers and to provide
adequate space for unit access for servicing and
maintenance. There is a possibility of recycling of air
if the rejected air from condenser encounters any
obstacles leading to an increase in the ambient air
temperature surrounding the units.
Air distribution across the entire heat exchange
area will be impaired if the air outlet is obstructed.
These conditions lead to a reduction in the
heat exchange capacity of the coils causing
an increase in discharge pressure of the
compressors. This leads to a loss of capacity &increase in compressor power input
Units should not be
completely shrouded
with higher uninterrupted
wind shield in order to prevent
reversing of airflow. In case, sucha confi guration cannot be avoided,
a properly designed exhaust duct
or hood that does not influence
any additional pressure a properly
designed exhaust duct or hood that
does not influence any additional
pressure on the fans and which of the
same hight as surrounding shield to be
installed.
PACV- 51008 S TO 52055S
PACV- 61009 S TO 62066S
DUCT
DUCT
B
If there are walls on one or two adjacent sides of the unit.
The walls may be of any height. If there are walls on more
than two adjacent sides of the unit. The walls should not behigher than the unit.
Do not locate outside air intakes near exhaust vents or
other sources of contaminated air.
If the unit is installed where windy conditions are common,
install wind screens around the unit.
Units surrounded byscreensor solid walls must have no
over head obstructions over any part of the unit.
The area above the condenser must be installed
unobstructed to allow vertical air discharge.
A flat concrete foundation or floor which can support the
weight of the equipment must provided as the unit must be
level for proper operation and functioning of controls.
Under certain critical conditions it is recommended thatvibration isolators of rubber-in-shear or spring type beinstalled under the base refer to loading points(Page 49).
Electrical
Pre-Installation Check-Up
IMPORTANT: When installi ng t he unit , always
disconnect the electric supply.
Make sure that the power supply is compliant with current
safety standards. Always install the air conditioner in
compliance with current local safety standards.
Verify that suitable grounding connection is available.
Verify that the voltage and frequency of the power supply
comply with the specifications and that the installed poweris sufficient to ensure the operation of any other domestic
appliance connected to the same electric lines.
Verify that the air conditioner is connected to the power
supply in accordance with the instructions provided in the
wiring diagram included in the manual.
Verify that electric connections (cable entry, section
of leads, protections....) are compliant with the electric
specification and with the instructions provided in the
wiring scheme. Verify that all connections comply with the
standards applicable to the installation of air conditioners.
Figure 9
Foundation
A flat level concrete foundation which can support the weight of
the equipment must be provided.
Where units are to be located, over steel trusses or on a steel
platform, careful analysis to ensure proper distribution of weight
onto the structural members should be ensured. The steel platform
should be strong enough to hold the operating weight.
-
7/24/2019 7.Installation,Operation & Maintenance(IOM)
16/65 16 |
OPERATION
Avoid installing the equipment in the
following:
In areas where it is exposed to
direct sunlight. Close to any heat
source.
In damp areas or locations where
it could come into contact with
water.
In areas where curtains and
furniture could affect the supply
and discharge of air.
In areas in which there is no
enough space around the unit.
(Must install as per the required/
recommended spacing, shown in
the lay out drawings).
On surfaces that are unable to
support the weight of the unit
without deforming, breaking or
causing vibrations when the unit
is running.
General
Do NOT install the equipment in a location
where it will come in contact with the
following elements :
Combustible gases
Saline air
Machine oil
Sulphide gas
Special environment conditions,
if you must install the unit in such
conditions, first consult SKM.
Carrying Out Installation
1. Unpack the unit carefully.
2. Unfasten or dismantle transport locks.
3. Packing material to be fully removed and disposed.
4. The unit base frame must be fixed without stresses to the
supporting structure.
5. AVM to be regularly placed around centre of gravity and
firmly fixed. Check whether AVM is balanced under load.
6. No forces or vibrations may be transferred from other plant
parts.
7. The flexible connections at intake and/or discharge should
be installed, well aligned and freely moving.
8. The AVM should be freely moving and under even load.
9. The impeller should be turning idly and should not touch
the intake cone.
10. The stability against collapse of the unit should be checked.
Preparation For Installation
When deciding on the location of the unit with the
owner, the following restrictions must be taken into
consideration:
The discharge air from the condenser fan
should not be obstructed by any roofing,
shelter, ducting etc. Any obstruction will
cause short circuiting of condenser fans leading
to reduction in capacity or nuisance tripping of
the PACV-Spackage unit from the high pressure
control and sometimes in motor burnout .
Condensate Draining
It is mandatory to install a properly sized drain trap in order toensure proper draining of condensate collected in the drain pan.
Below mentioned are recommendations for sizing a drain trap.
Measure the maximum negative static pressure upstream from
the fan. The height H1 shown in belowfigures must be greater
than or equal to the negative static pressure at design conditions.
Ensure that there is sufficient water in the trap before starting in
order to maintain the seal.
H1= 1 f or each 1 of negative static pressure + 1
H2= H1/2
H= H1 + H2+ Pipe Diameter + Insulation
Condensate traps serving the cooling coils should be of sufficient
height to be effective.
The unit should be located on a suitable base to provide adequate
height from the ground in order to accommodate the drain trap.
Figure 10
-
7/24/2019 7.Installation,Operation & Maintenance(IOM)
17/65 | 17
OPERATION
Pre-Startup Procedure
After the installation has been completed, the following points
should be covered before the system is placed in operation.
Precaution: Carry out a fan test run
Risk of injury from rotating impeller!
Never reach into t he impeller when the fan
is in operation.
a. Check electrical connections. Be sure they
are all tight.
b. Observe compressor oil level before start-up.
The oil level should be at or slightly above the
center of the sight glass. Use only oil approved
by compressor manufacturer.
c. Remove or loosen shipping retainers undermotor- compressors. Make sure hold down
nuts on spring mounted compressors are nottouching the compressor feet.
d. Check high and low pressure controls,pressure regulating valves and all other safety
controls, and adjust if necessary.
e. Check refrigerant used in the system.
f. Wiring diagrams, instruction bulletins, etc
attached to PACV-S units should be read
and filed for future reference.
g. Make the proper refrigerant connections
and charge the unit with the refrigerant to
be used. Weigh the refrigerant drum before
charging so an accurate record can be kept
of the weight of refrigerant put in the system.h. Observe system pressures during charging
and initial operation. Do not add oil while the
system is short of refrigerant, unless oil level
is dangerously low.
i. Continue charging until system has sufficient
refrigerant for proper operation. Do not over-
charge. Remember that bubbles in a sight
glass may be caused by a restriction as well
as a shortage of refrigerant.
j. Do not leave unit unattended until the system
has reached normal operating conditions and
Pre Startup Checklist
Make sure the power supply voltage and frequency
are as given in the unit name plate.
Make sure that unit has been installed in accordance
with the installation instruction and applicable codes.
Check all electrical connections in unit control panel;
tighten them as required.
Make sure the compressor oil level is within the
sight glass range.
Check the power supply phase sequence for proper
direction of rotation of motors.
Make sure all system hand valves are in fully open
position and system contains an operating charge
of refrigerant.
Switch on the power supply to the unit
Crank case heaters of all compressors to be
energized at least 24 hours prior to start up.
PACV-S unit is factory charged
Please make sure to open supply air
dampers fully (if any) before starting the
fan motor. Otherwise, blower fan can be
damaged due to back pressure and warranty
will be void.
Take measures to prevent centrifugal fan
from being switched on accidentally.
Clear the ducting system and fan of all foreign
bodies (tools, small parts, construction
waste, etc.).
Close all the inspection openings.
Switch on fan and check direction of rotation
of impeller by comparing it with the arrow on
the fan indicating the direction of rotation. If the direction of rotation is wrong, reverse
the polarity of the motor having due regard to
the safety instructions.
Once operating speed has been reached
measure the current consumption and
compare it with the nominal motor current on
the fan type plate or motor rating plate.
If there is continuous overload switch the
centrifugal fan off immediately.
Check that the fan runs smoothly and quietly.
Ensure that there are no unusual oscillations
or vibrations.
Check the motor for any abnormal noises.
Prior to starting up the unit, we
recommend checking if the following
steps have been carried out:
the oil charge has been properly adjusted to maintain the oil level
at the center of the sight glass.
If the state of the fan does not allow adapted
action for repair it has to be put out of
order immediately and to be replaced if
required.
-
7/24/2019 7.Installation,Operation & Maintenance(IOM)
18/65 18 |
OPERATION
Operational Check-Out
After the system has been charged and has operated for
at least two hours at normal operating conditions without
any indication of malfunction, it should be allowed to operate
over-night on automatic controls. Then a thorough recheckof the entire system operation should be made as follows:
a. Compressor manufacturer model and serial number.
b. Equipment manufacturer model and serial number.
c. Design operating temperatures.
d. Refrigerant and weight of charge.
e. Electrical service, volts, cycles, phase, wire size.
f. Control circuit, voltage, breaker size.
g. Contactor or starter, manufacturer, model, size, part
number.
h. Compressor motor protection(if available), type, size,
part number.
i. Data on relays or other electrical components.
j. Pressure control, type, size, model number, setting.
k. Data on miscellaneous components such as pressure
controls, crankcase heaters, solenoids, valves, etc.
l. Liquid line drier, manufacturer, size, model number,
connections.
m. Schematic diagram of refrigerant piping.
n. Final settings on all pressure, regulating and safety
controls.
o. Microprocessor details
a. Check compressor head and suctionpressures. If not within system design limits,
determine why and take corrective action.
b. Check liquid line sight glass and expansion
valve operation. If there are indications that
more refrigerant is required, leak test allconnections and system components and
repair any leaks before adding refrigerant.
c. When applicable, observe oil level in
compressor crankcase sight glass, and addoil as necessary to bring level to center of
the sight glass.
d. Thermostatic expansion valves must be
checked for proper superheat settings.Sensing bulbs must be in positive contact with
the suction line. Valves with high superheat
settings produce little refrigeration and poor
oil return. Too little superheat causes low
refrigeration capacity and promotes liquid
slugging and compressor bearing washout.
Liquid refrigerant must be prevented from
reaching the crankcase. If proper control
cannot be achieved with the system in normaloperation, a suction accumulator must be
installed in the suction line just a head of the
compressor to prevent liquid refrigerant from
reaching the compressor.
e. Using suitable instruments, carefullycheck line voltage and amperage at the
compressor terminals. If high or low voltage
indicated, notify the power company. The
current normally should not exceed 120%
of the nameplate rating. If amperage draw
is excessive, immediately determine the
cause and take corrective action. On three
phase motor-compressors, check to see that
a balanced load is drown by each phase.
f. All fan motors on air cooled condensers,
evaporators, etc should be checked for
proper rotation. Fan motor mounts should
be carefully checked for tightness and properalignment. If belt drives are used, check the
belt tension. All motors requiring lubrication
should be oiled or greased as necessary.
Service Record
A permanent data sheet should be prepared on each
installation, with a copy for the owner and the original for the
installing contractors files. If any other firms are to handle
service and maintenance, additional copies should be prepared
as necessary.The form of the data sheet may vary, but a complete record
of sizes and identification of all components used in theinstallation, together with any pertinent information should be
included. Following is suggested check-off list:
-
7/24/2019 7.Installation,Operation & Maintenance(IOM)
19/65 | 19
OPERATION
Unit Start Up
Sequence of OperationThe unit may be enabled or disabled through the Run/
Stop toggle switch in the unit mounted control panel or
from the room unit on/off button. Control is based on room
temperature sensed by room unit(for units with duct sensor
,control is based on duct temp). Evaporator fan motor
starts first. Compressors will be staged based on the set
point and actual room temperature. On an increase inroom temperature, cooling stages will be added and
on a decrease in room temperature, cooling stages
will be removed from the system. Sequence for the
compressors and motors are as given below:
Switch on the three phase power supply to the unit.
Switch on the control circuit breakers. Unit controller
will start up.
Check for any alarms in the controller. If there are
any alarms, correct the cause and clear them.
Turn on the Run/Stop toggle switch in the unit
control panel.
Press the power button in the room unit. Then
supply fan will start.
Make sure the refrigerant circuits are enabled in
the relevant circuit screen in the controller display.
Compressors will start based on the temperature setpoint set in the room unit and the indoor temperature.
Make sure that the unit is in cooling mode, which
can be selected from the room unit.
Condenser fans will start with compressors and will
cycle based on discharge pressure.
Supply FanSupply fan will be switched on if the belowconditions are satisfied.
Controller start up is finished.
Run/Stop switch in the unit controlpanel is ON.
Room unit power icon is ON.
Room unit schedule is ON (If schedule is
disabled, then unit will run continuously)
Communication between unit controller
and room unit is healthy.
Motor overload is healthy.
Voltage Monitor is healthy.
Supply fan has two modes; ON (continuouslyON) or AUTO (ON when there is cooling or
heating demand).
Compressor
Compressor will switch on if the below conditions
are satisfied.
Compressor minimum OFF time
completed.
Supply fan runs for 30 seconds.
Circuit enable (from controller display)
is enabled. Unit is in cool mode.
Demand for compressor is present.
Discharge pressure and motor protector
module (if available in compressor) are healthy.
If above are satisfied, solenoid valve will be opened
and when the low pressure switch closes, compressor
will be started.
A typical two compressor control is as shown below:
Condenser fans
Condenser fans will switch on with associated compressor(s)
and cycle based on discharge pressure.
For single compressor units or units with circuits having
independent condenser fans, condenser fans will be
switched on based on the discharge pressure of that
circuit. Each fan will switch on if pressure is above the
stage on value and will switch of if the pressure is below
stage off value.
For units with more than one compressor sharing the
condenser fans, the highest pressure among the circuits
will be taken to cycle the fans.
Unit Control ler Display and Keypad
The keypad/display of the controller consists of a 64 x 144 screen
resolution 5 line 22 character display screen,3 buttons and a push
& turn knob for navigation.
Buttons
Info button: This is used to enter the unit information screen
where the SKM Unit model & serial number can be viewed.Alarm but ton: This is used to enter directly the alarm screen for
viewing the alarm details & to reset them manually if required.
Esc button:This is a back button to move back to the previous
screen or to the home screen.
Push & Turn Knob
This is a navigation wheel that can be rotated as well as pushed.
Rotating the wheel navigates between the lines of the screenand also to change/edit the changeable values on the screen.
Clockwise rotation increases the values and anti-clockwise rotation
decreases the value. Pushing the wheel acts as an Enter button
to acknowledge the changed value.
-
7/24/2019 7.Installation,Operation & Maintenance(IOM)
20/65 20 |
OPERATION
If supply fan is not starting, navigate to these screens to find out
the reason. In order for the supply fan to start, the Run/Stop input
should be Run, Room Unit should be On, Schedule Status
should be On in case the schedule is enabled, Motor over load
should be healthy and Voltage monitor should be healthy.
Circuit ScreenEach circuit screen will show the status of all the inputs and
outputs related to that circuit.
These will show the status of supply fan motor (On or Off), Circuit
enable/disable selection, Unit mode (Cool, Heat, Auto or Vent),
Discharge pressure (Healthy or Trip), Suction pressure (Healthy
or Trip), compressor motor protectors if available (Healthy or
Trip), compressors (On or Off) and liquid line solenoid valve
(Open or Closed).
Note that circuit can be enabled or disabled from the controller
display itself. In order to do that, highlight the Circuit Enable line
and then press the navigation wheel. Then rotate the navigation
wheel in order to enable or disable the circuit and then press
the wheel.
Unit operating mode selection is from the Room unit.
Condenser fans
These screens will show the discharge pressures of each circuit
and status of the condenser fans.
Schedule
The schedule screen will allow setting the On time and Off time
for each day of the week. If the schedule is enabled, then unit
will work based on this schedule only.
Set poin ts
This screen will show the temperature set point and actual indoor
temperature (or duct temperature if optional duct sensor is used).
If factory password is entered, then set points screen will show
access to factory parameters as well.
The main displayscreen consists of a5 line display, with
the first linedisplayingthe page title and a numeric display
of the number ofalarms along with the symbol if any
alarmsare present. Second& third lines display the date &
time respectively. There arethreesubmenus inthe display
namely, SYSTEMOVERVIEW, PASSWORD &ALARMS.
Everypagecan consist of data fields, eitherchangeable or with
information only. As the cursormoves over each line, thetext
in thelineis highlighted with ablackbox around it and the text
turning white. As thenavigation wheel is rotated thesubsequent
lines get highlighted witha black box around them. When a line
consists of anarrow in the far rightof the page, it isreferred to as
amenu group. When the navigation wheel ispushed, the display
goesto a new page consisting of thesubmenus. Thetitleof the
menu group appears as the title of the new page.
Figure:Rotation of the navigation wheel
Figure: Pushing the navigation wheel
The system overview menu consists of information on
thesupply fan, circuits, condenserfans, andset points.
These submenus give more information on the unit
including safeties and status of compressors, motors
and setpoints. Different screensof thecontrollerare
as given below.
Main ScreenThis screen will show date & time,system over view,
password & alarms.
SystemOverviewSelecting thesystem overviewwill lead tobelow
screens
Fromthe abovetwo screens, further navigation
is possible to different screenswhich will giveinformation about supply fan,each refrigerant
circuit, condenser fans, schedule and set points.
Supply fan
Thebelow screens will give information about all
theinputs andoutputs relatedto supply fan.
Display and Keypad operation
.
-
7/24/2019 7.Installation,Operation & Maintenance(IOM)
21/65 | 21
OPERATION
Factory parameters will show Compressor Minimum offtime, Compressor Minimum On time, Low pressure alarm
delay, Cooling step, Cooling Differential, Condenser Stage1
On pressure, Condenser Stage1 Off pressure, Condenser
On Differential pressure, Condenser Off Differential pressure,
Schedule enable/disable, Clearing alarm history and software
BSP version of the controller.
Note that factory parameters should be changed only by SKM.
Unit InformationThis screen will provide the information about the unit model
name and SKM serial number.
Alarms
This screen will show alarm list and alarm history.
Pressing the alarm list will show all the active
alarms. All alarms will be with date & time and will
be in easily readable English language.
Note that some of the alarms (like high
discharge pressure) are manual reset. In orderto acknowledge the manual reset alarms, follow
below steps.
Below Screen will appear.
Rotate the Navigation wheel and then screen will show
Exe...
Press the navigation wheel and all the alarms which are
not active will get reset.
List of Alarms in the Unit Controller
Below are the various alarms configured in the Unit controller.
Supply Fan Motor: Trip
This alarm occurs when the overload of supply fan motor detects
an overload condition in the motor. When this alarm happens,
entire unit will be switched off. This alarm is auto reset as standard.
Voltage Monitor: Trip
This alarm occurs when the voltage monitor connected in the
main incomer detects an under voltage or over voltage or phase
reversal or phase imbalance or single phasing condition. Whenthis alarm happens, entire unit will be switched off. This alarm is
auto reset as standard.
Room Unit Communication: Lost
This alarm occurs when the unit controller looses communication
with the room unit. When this alarm happens, entire unit will be
switched off. This alarm is auto reset as standard.
Circuit-# Suction Pressure: Trip
This alarm occurs when the low pressure switch senses a low
suction pressure in the refrigerant circuit. This alarm will be
generated, if one refrigerant circuit is On for cooling demand
and the low pressure switch doesnt close for a specific time (low
pressure alarm delay set point). When this happens, corresponding
circuit will be switched off and alarm will be generated. This alarm
is automatic reset as standard.
Circuit-# Discharge Pressure: Trip
This alarm occurs when the high pressure switch senses a
high discharge pressure in the refrigerant circuit. This alarm
will be generated, if the high pressure switch remains open for
one second. When this happens, corresponding circuit will be
switched off and alarm will be generated. This alarm is manual
reset as standard.
Compressor-# Motor Protector: Trip
This alarm will be generated only for those compressors with a
built in electronic motor protector module. It occurs when the motor
Enter the user password 1234 (Refer
Passwords)
Go to alarm list screen and press
acknowledge
-
7/24/2019 7.Installation,Operation & Maintenance(IOM)
22/65 22 |
OPERATION
If the room unit address is not set correctly, it will display as
below (P- - blinking).
Passwords
In order to enter the password, use Password screen.Follow the below steps.
Go to the Password screen in the Main Menu.
Use the navigation wheel to enter password
(Rotate to change and Press to select.). If user
password is required, enter 1234.
Once the password is entered, a number
corresponding to the password level will
appear on left top of the screen. For user
password, it will be 4.
Operation of the Room Unit
The room unit displays indoor temperature (duct temperature if
optional duct sensor is used), temperature set point, unit on/off
status, unit operating mode, fan mode, day of the week, time of
the day and schedule. Room unit will let the user to make the
unit on/off, change the operating mode, change the fan mode,adjust the set point, change the temperature measurement unit,
change date & time and operating schedule.
Adjust the set point, change the temperature measurement unit,
change date & time and operating schedule.
Press power button, mode button, minus button and
plus button simultaneously as shown below.
Setting the address in Room Unit
Room unit will display the software version as below.
Press mode button; room unit will display parameter 001
as below, with 001 blinking
22 |
asswor s
In order to enter the password, use Password screen.Follow the below steps.
Go to the Password screen in the Main Menu.
wordUse the navi ation wheel to enter ass
(Rotate to change and Press to select.). If user
password is required, enter 1234.
Once the password is entered, a number
corresponding to the password level will
appear on left top of the screen. For user
password, it will be 4.
Power Button
Minus Button
Mode Button
Plus Button
protector module senses a high internal temperature
in the compressor. When this happens, corresponding
circuit will be switched off and alarm will be generated.
This alarm is automatic reset as standard.
-
7/24/2019 7.Installation,Operation & Maintenance(IOM)
23/65 | 23
OPERATION
Press plus button multiple times to reach
parameter 005. At this stage parameter 005
will be blinking. On pressing mode button;
parameter value will start blinking. Use plus
button or minus button to make it 005 as
shown below (if it is already 0005, no need
to do this step). Press mode button again,
then parameter 005 will start blinking.
Press plus button to reach parameter 006.
At this stage parameter 006 will be blinking.
Press mode button and then use plus
button or minus button to make the value
0002 (if it is already 0002, no need to do
this step). Press mode button again, then
parameter 006 will start blinking.
Press plus button to reach parameter 007. At
this stage parameter 007 will be blinking. Press
mode button and then use plus button or
minus button to make the value 0003 (if it is
already 0003, no need to do this step). Press
mode button again, then parameter 007 will
start blinking.
Press plus button multiple times to get back
to parameter 001. Then press power button,
the version screen will be displayed.
Press power button again, then room unit
will show normal display as below.
Switching on and switching off the unit
Press the button to make the unit on and off. When the unit is
on, will be shown on the display.
Changing the Unit operating mode
Operating mode of the unit can be changed by pressing button.There are two modes for cooling only units and four modes for
units with electric heater. The modes are cool ( ), heat ( ),
auto cool-heat ( ) and Vent ( ). Note that in vent mode,
compressors or heaters ( if available ) will not operate.
Changing the fan operating mode
Operating mode of the fan can be changed by pressing the button.
There are two modes for the fan which are Auto ( ) and On ( ).
Auto means the supply fan will run only when there is cooling or
heating demand. On means supply fan will run continuously. Inthe units where there is much changes in temperature, always
use On mode.
Changing the Set poin t in Room Unit
Press + and - buttons to adjust the temperature set point.
Changing the Temperature display un it
Long press the button to toggle the temperature display unitbetween oCelsius and oFahrenheit.
Alarm Indication
In case if there is any alarm present in the unit, will blink onthe room unit display. Once the alarms are cleared from the unit
controller, then the alarm symbol will disappear.
Time and Day of the week
Room unit will show the time in 12 hour format and the day of
the week. Day of the week will be 1 for Monday, 2 for Tuesday,
3 for Wednesday, 4 for Thursday, 5 for Friday, 6 for Saturday
and 7 for Sunday.
Time and Date Setting
By pressing the button, user will enter time and date setting.
Pressing + or -button can change the variables those are
blinking on the screen, while pressing button will confirm the
changes and the cursor will move to the next variable automatically.
The first view is time setting, user can change 3 items: hour,minute and time for-mat. The view is showed as follows:
Firstly the hour area will be blinking; pressing + or - canchange the number of hour, pressing will confirm the changes
and the cursor will move to the minute area automatically.
After the number of minute is confirmed, the whole time areawill blink. Pressing + or -button will switch time format
between 12-hour with AM/PM and 24-hour. It will shows as
)
-
7/24/2019 7.Installation,Operation & Maintenance(IOM)
24/65 24 |
OPERATION
After the year is confirmed, it will jump to the view of month
and day. The view is showed as follows:
After the month and day is confirmed, HMI-SG will return
to the view of time. Press button PROG or there is no any
operation for 1 minute, it will exit the setting.
follows in 24-hour time format:
After the time format is confirmed, HMI-SG will jumpto the view of year. It will show as follows:
ENTER PASSWORD
ENTRY ****
CIRCUIT-1SUPPLYFAN MOTOR : OFF
CIRCUIT1 ENABLE : ENABLE
UNIT MODE : VENT
DISCH.PRES.-1 : TRIP
SUCT.PRES-1 : HEALTHY
COMPRESSOR-1 : OFF
SOL.VALVE-1 : CLOSED
SUPPLY FAN
RUN/STOP INPUT : STOP
ROOM UNIT : ON
ON/OFF SCHEDULE : ENABLE
SCHEDULE STATUS : ON
FAN MODE : ON
MOTOR OVERLOAD : TRIP
VOLTAGE MONITOR : TRIP
SUPPLY FAN MOTOR : OFF
CIRCUIT-2
SUPPLYFAN MOTOR : OFF
CIRCUIT2 ENABLE : ENABLE
UNIT MODE : VENT
DISCH.PRES.-2 : TRIP
SUCT.PRES-2 : HEALTHY
COMPRESSOR-2 : OFF
SOL.VALVE-2 : CLOSED
CONDENSER FANS
DISCH.PRES.-1 : XX.X PSI
DISCH.PRES.-2 : XX.X PSI
_____________________________FAN-1 : OFF
FAN-2 : OFF
FAN-3 : OFF
FAN-4 : OFF
SCHEDULE
MONDAY:
SCHEDULE-1: HH: MM-HH:MM
TUESDAY:
SCHEDULE-1: HH: MM-HH:MM
WEDNESDAY:
SCHEDULE-1: HH: MM-HH:MM
THURSDAY:
SCHEDULE-1: HH: MM-HH:MM
FRIDAY:
SCHEDULE-1: HH: MM-HH:MM
SATURDAY:
SCHEDULE-1: HH: MM-HH:MM
SUNDAY:
SCHEDULE-1: HH: MM-HH:MM
MAIN MENU
DATE
TIME
SYSTEM OVERVIEW
PASSWORD
ALARMS
SYSTEM OVERVIEW
SUPPLY FAN
CIRCUIT-1
CIRCUIT-2
CONDENSER FANS
SCHEDULE
SETPOINTS
HMI PASSWORDENTER PASSWORD
CLOSE ACCOUNT
ALARMS
ALARMLIST
ALARMHISTORY
FACTORY SETTINGS
COMP.MIN.OFF TIME : XXX s
COMP.MIN.ON TIME : XXX s
LP ALARM DELAY : XXX s
COOLING STEP : XX.X C
COOLING DIFF. : XX.X C
COND.STG1 ON : XXX PSI
COND.STG1 OFF : XXX PSI
COND.DIFF.ON : XXX PSI
COND.DIFF.OFF : XXX PSI
ON/OFF SCHEDULE : Enable
SETPOINTS
TEMP.SETPOINT : XX.X C
: XX.X C
FACTORY SETTINGS
BSP VERSION
CLEAR ALM HIST
: X.XX: PASSIVE
INDOOR TEMP
An Overview Of Menu Structure
-
7/24/2019 7.Installation,Operation & Maintenance(IOM)
25/65 | 25
OPERATION
Table 5
-
7/24/2019 7.Installation,Operation & Maintenance(IOM)
26/65 26 |
MAINTENANCE
26 |
Periodic MaintenanceFollowing Checklist describes the suggested maintenance schedule to maintain proper operation of the unit. Detailed
procedures are mentioned in the corresponding pages.
The above mentioned schedule is typical and will vary largely based on si te conditions.
Table 6
Component Checkl ist Weekly Month ly Hal f Yearly Annual ly
EvaporatorFan/MotorSection
General Yes
Check for Corrosion andRepaint as Necessary
Yes
Check amperage draw onblower motor
Yes
Check condensate lineand clean if necessary
Yes
Check for correct voltageat unit
Yes
Motors General Check Yes
Check for unusual noisefrom the motor
Yes
Check all wiring for loose
connectionsYes
Filter SectionAir filter to be washed &cleaned
Yes
Evaporator CoilSection
Check for Debris /Blockage over fins & cleancoil if necessary
Yes
Check connecting lines,joints & coil for evidenceof oil leaks
Yes
Operation LevelMaintenance
Oil Level at Sight Glass Yes
Superheat at Compressor Yes
Crank Case HeaterOperation
Yes
Refrigerant Sub cooling inLiquid Line
Yes
Operating Pressures Yes
Control Panel
Dust & Debris on PowerTerminals/ Contactors/Loose Cable Lugs
Yes
Check for correct voltageat unit (Unit operating)
Yes
Check Unit Operation Yes
Check for alarms in UnitMicroprocessor
Yes
Condenser Fan& Motor
Check for Vibrations &Noise
Yes
Check unbalance of theFan
Yes
Motor Bearings to bechecked
Yes
Corrosion Yes
Fan Blades to be checked/Balancing
Yes
Condenser CoilSection
Check connecting lines ,joints & coil for evidenceof oil leaks
Yes
Clean & inspect outdoorcoil , wash with water ifnecessary
Yes
-
7/24/2019 7.Installation,Operation & Maintenance(IOM)
27/65 | 27
MAINTENANCE
Never use oxygen fo r pressurizing a
system; an explosion may occur if oil
is present in the system. Always use
a gauge equipped pressure regulator
on the high pressure back-up gas, and never
interconnect the refrigerant cylinder and the
inert gas cylinder through a gauge manifold.
Nitrogen and carbon dioxide cylinder pressures
can rupture a refrigerant cylinder.
6.Apply heat evenly over the length and circumference of thejoint to draw the brazing material into the joint by capillaryaction. Remove the brazing rod and flame from the joint assoon as a complete fillet is formed to avoid possible restriction
in the line.
7. Visually inspect the connection after brazing to locate anypin holes or crevices in the joint .
Never solder, braze or weld on
refrigerant lines or any unit
components with pressures that are
above atmospheric pressure or where
refrigerant may be present. Always remove
refrigerant by following the local guidelines.
Af ter ref rigerant removal, use dry ni trogen to
bring system back to atmospheric pressure
before opening system for repairs. Mixtures of
refrigerants and air under pressure may become
combustible in the presence of an ignition sourceleading to an explosion. Excessive heat from
soldering, brazing or welding with refrigerant
vapours present can form highly toxic gases
Failure to follow all proper safe refrigerant
handling practices could result in death or
serious injury!
Maintenance
The maintenance of this equipment shall be in accordance
with the regulation of authorities having jurisdiction and
all applicable codes. It is the responsibility of the installer
to determine and follow the applicable codes. Low head
pressure may lead to poor, erratic refrigerant feed control at
the thermostatic expansion valve. The units have automatic
control of the condenser fans which should provide adequate
head pressure control down to 50 F (10 C) provided the
unit is not exposed to windy conditions. The system design isresponsible for assuring the condensing section is not exposed
to excessive wind or air recirculation.
ProceduresIt is quite probable that a majority of operating failures can be
traced to careless or inadequate maintenance procedures. The
following instructions have been prepared to help the service
engineer systematically cover the many points which must
be considered to provide each installation with trouble freeperformance.
Take extreme care to keep refrigeration tubing clean and
dry prior to installation. The following procedures should be
followed:
Brazing Procedures
1. When copper is heated in the presence of air,Copper oxide forms. To prevent copper oxide fromforming inside the tubing during brazing, an inert gas
should be passed through the line at low pressure
to prevent scaling and oxidation inside the tubing.
Dry nitrogen is preferred. Nitrogen displaces air
in the tubing and prevents oxidation of the interior
surfaces. A pressure regulating valve is to be usedto control the flow.
2. Ensure that the tubing surfaces to be brazedare clean, reaming at the ends of tubes isto be done to remove any burrs and keep the
surface even.
3. Make sure the inner and outer tubesof the joint are symmetrical and have aclose clearance, providing an easy slip fit. If
the joint is too loose, the tensile strength of
the connection will be significantly reduced.
The overlap distance should be equal to the
diameter of the inner tube.
4. Wrap the body of each refrigerant linecomponent like expansion valve, solenoidvalve, Hot gas bypass with a wet cloth to keep
it cool during brazing. Move any tube entrance
grommets away for the brazing area.
5. Flux , when used is to be applied in smallquantities only. Excessive flux, when used,can enter the system and contaminate the
refrigerant system.
-
7/24/2019 7.Installation,Operation & M