Data Aire LCS User manual

LCS
Installation, Operation and Maintenance Manual
6, 8, 10 and 13 ton
Air, Water and Glycol Cooled DX and Chilled Water

Congratulations!
You have selected a Data Aire precision control system, one of the finest available in
the market today. Proper installation, operation and maintenance of this equipment
will ensure years of optimal performance.
This manual is intended to assist trained service personnel by providing
necessary guidelines for this particular equipment. Service to Data Aire units
should be done by qualified individuals with an adequate background in areas
such as HVAC, electrical, plumbing and electronics, as applicable.
Service performed by unauthorized or unqualified technicians may void
manufacturers’warranties and could result in property damage and/or personal
injury.
Special care should be given to those areas where these symbols appear.
Data Aire, Inc. reserves the right to make design changes for the purposes of
product improvement, or to withdraw any design without notice.

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Table of Contents
1.0 INSTALLATION ........................................................................................................6
1.1 Room Considerations ....................................................................................................6
1.2 Inspection .......................................................................................................................6
1.3 Locating the Unit.............................................................................................................6
1.3.1 Horizontal Airflow Units .............................................................................................7
1.3.2 Vertical Airflow Units..................................................................................................7
1.4 Paperwork.......................................................................................................................7
1.5 Storage...........................................................................................................................8
1.6 Model Identification.........................................................................................................8
2.0 PIPING ........................................................................................................................9
2.1 Split Air Cooled Unit Piping.............................................................................................9
2.1.1 Discharge Lines.........................................................................................................9
2.1.2 Liquid Lines...............................................................................................................9
2.1.3 Suction Lines.............................................................................................................9
2.1.4 Connection Sizes, Air Cooled Units.........................................................................10
2.1.5 Field Piping, Remote Condenser ............................................................................11
2.1.6 Field Piping, Remote Condensing Unit ...................................................................11
2.2 Water/Glycol Cooled Unit Piping ..................................................................................12
2.3 Auxiliary Chilled Water Coil Piping ...............................................................................13
2.4 Condensate Drain Piping..............................................................................................13
2.5 Humidifier Piping...........................................................................................................13
2.6 Dry Steam Humidifier....................................................................................................13
2.7 Leak Testing..................................................................................................................14
2.8 Evacuation....................................................................................................................14
3.0 ELECTRICAL CONNECTIONS ..........................................................................15
3.1 Electrical Service..........................................................................................................15
3.2 Nameplate Ratings.......................................................................................................15
3.3 Grounding.....................................................................................................................15
3.4 Voltage Tolerance.........................................................................................................15
3.5 Auxiliary Control Wiring ................................................................................................15
3.6 Remote Shutdown........................................................................................................16
3.7 Remote Alarm Contacts................................................................................................16
3.8 Remote Sensors...........................................................................................................16
3.9 Condensate Pumps......................................................................................................16
4.0 INSTALLATION OF REMOTE OUTDOOR HEAT EXCHANGER .............17
4.1 Rigging..........................................................................................................................17
4.2 Leg Assembly ...............................................................................................................17
4.3 Locating the Remote Heat Exchanger..........................................................................17
4.4 Electrical Service..........................................................................................................18

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Table of Contents, continued
4.0 INSTALLATION OF REMOTE OUTDOOR HEAT EXCHANGER - (continued)
4.5 Air Cooled Condensers - Model DARC .............................................................................18
4.5.1 Fan Speed Control.......................................................................................................18
4.5.2 Ambient Thermostats...................................................................................................18
4.6 Fluid Coolers - Model DAFC..............................................................................................19
4.6.1 Fluid-Sensing Thermostats ..........................................................................................19
4.6.2 Energy Saver Cooling ..................................................................................................19
5.0 CHARGING ...................................................................................................................20
5.1 Voltage Phase Check ..........................................................................................................20
5.1.1 Evaporator....................................................................................................................20
5.1.2 Secondary Heat Exchanger .........................................................................................20
5.2 Air Cooled Systems......................................................................................................20
5.2.1 Split Indoor Air Cooled Systems Charging...................................................................20
5.2.2 Fan Speed Control System Charging...........................................................................21
5.2.3 Flooded System Charging............................................................................................21
5.3 Water/Glycol Cooled Systems......................................................................................22
5.3.1 Water/Glycol Cooled Systems Charging......................................................................22
5.4 Refrigerant Handling ....................................................................................................23
5.5 Important Refrigeration Components...........................................................................23
5.5.1 Expansion Valve...........................................................................................................23
5.5.2 High Pressure Cutout Switch......................................................................................24
5.5.3 Low Pressure Cutout Switch........................................................................................24
6.0 GLYCOL SYSTEMS ...................................................................................................24
6.1 Glycol Concentration .........................................................................................................24
6.2 Internal (Fluid) Volume.......................................................................................................24
6.3 Fluid Cooler Internal Volume .............................................................................................24
6.4 Copper Piping Internal Volume..........................................................................................25
6.5 Freezing Point of Aqueous Solutions.................................................................................25
7.0 CONTROLS ..................................................................................................................25
7.1 Mini dap4 Controller...........................................................................................................25
7.2 Optional Expanded dap4 Controller...................................................................................25
7.3 Secondary Heat Exchangers.............................................................................................25
7.4 Wiring Diagrams................................................................................................................26

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Table of Contents, continued
8.0 REGULAR MAINTENANCE ITEMS (continued)
8.4 Humidifier Canisters .........................................................................................................27
8.5 Fuses................................................................................................................................28
8.6 Heating Elements .............................................................................................................28
8.7 Refrigerant Filter Drier......................................................................................................28
9.0 WARRANTY ................................................................................................................29
10.0 CONTACT DATA AIRE ...........................................................................................30
Line Sizing Chart .......................................................................................................................31
Monthly Maintenance Inspection Checklist ...............................................................................32
Quarterly Maintenance Inspection Checklist .............................................................................33
Superheat and Suction Pressure Troubleshooting Guide .........................................................34
Temperature Pressure Chart for R-407c and R-410a.................................................................35
INDEX ...............................................................................................................................36-37

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1.0 INSTALLATION
There is no intent on the part of Data Aire, Inc. to define local codes or statutes which
may supersede common trade practices. The manufacturer assumes no responsibility
for their interpretation. Consult local building codes and the National Electrical Code
for special installation requirements.
1.1 Room Considerations
Precision air conditioning equipment is designed to control spaces within close tolerances of
temperature and humidity. However, the room must be built with a proper vapor barrier. A film of
polyethylene is often used on walls and ceilings. Walls and floors must also be painted with a vapor-
seal paint. All doors to the controlled space should be equipped with weather seals to prevent the
infiltration of non-neutral conditioned air from external spaces. Failure to provide a vapor barrier can
compromise the ability to control space conditions.
Introduction of outside air into the space should be minimized. Outside air in excess of 5% of the
total circulated air volume can have a significant effect on the overall space conditions and result
in poor space control. All outside air that is introduced should be conditioned to the humidity and
temperature parameters of the computer room air conditioner (CRAC) unit set points to maintain
proper room conditions and to prevent the CRAC units from running excessively to maintain the
room’s conditions.
1.2 Inspection
This Data Aire unit has been factory run-tested and has gone through a comprehensive inspection
prior to its packaging and shipment to ensure that it arrives in excellent condition. However, shipping
damage can occur and a visual inspection of the outer crating immediately upon delivery should be
performed.
Note any external damage or other transportation damage on the freight carrier’s forms. Inspect the
unit itself for internal damage. A claim should be filed with the shipping company if the equipment
is damaged or incomplete.
Looseitems suchas remotecontrol panels,disconnectswitchhandles,sparebeltsandspare filters
are packed inside the unit. Refer to the manila shipping tag located on the unit panel for details.
Freight damage claims are the responsibility of the purchaser. Action to recover
losses should be filed immediately. Please notify factory personnel of any claims.
1.3 Locating the Unit
The unit is intended for above the ceiling installation and is typically suspended from structural
members in the building above the ceiling. Add at least a 50% safety factor to the weight of the unit
to determine the necessary strength of the supporting structural members or follow local code.
Appropriate service access above the ceiling is required around all service and electrical access
panels. There must be unobstructed clearance below the unit allowing ladder access to enable
routinemaintenance andservice. Consult localbuilding codesand NationalElectric Codefor special
installation requirements.

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Note: There are many available unit configurations for the LCS. Be sure to identify the
unittype andstylebefore installing. Forinstancethere maybesplit condenser/condensing
sections requiring separate or shared power.
Note to Installing Contractor: Condensation formation and frequent humidifier flush-
ing (when humidifier is installed) are normal functions of this equipment. Drain connec-
tions must be made to ensure proper water removal. Unit will require drain connections
for condensate removal and water connections possibly for humidifier (when installed)
makeupwater,condenserwater,chilledwater and/orhot water. Installationof unitsabove
equipment that could sustain water damage should be avoided.
1.3.1 Horizontal Airflow Units
All LCS units have horizontal airflow configuration with a 29.5” tall evaporator section. Duct collars
are factory provided for the supply and return air.
Four threaded support rods must be securely attached to the building structure. Two field provided
support channels connect to the pairs of threaded support rod. (See detail on drawing 536-900-100
shown on page 38.) Raise the evaporator section with an appropriate lifting device.Attach washers,
nuts and jam nuts to each threaded rod. Tighten the nuts so the weight is supported evenly by the
four rods and the unit is level.
1.3.2 Indoor Condensers and Condensing Units
Although most split air cooled systems have outdoor condensers or condensing units, indoor
condensersand condensingunits areoccasionally used. These29.5” tallsectionsare tobe mounted
in the same manner as the evaporator sections using four threaded rods. Air cooled condensers
or condensing units have factory provided duct collars on the supply and intake air openings as
appropriate.
Typical installations have the condenser or condensing section physically near the evaporator,
especially since most have some shared electrical line power. The mounting of these sections is
independentof theevaporatormounting. Thesameserviceandmaintenanceclearancerequirements
apply to these units as well.
1.4 Paperwork
Each Data Aire unit ships with a start-up sheet that must be completed during installation. Also
included in the paperwork is a warranty/information packet that provides important wiring diagrams,
specific component literature, warranty registration card and other valuable paperwork, including a
copy of this Installation/Operation and Maintenance manual.
Amanila(yellow) tagisattached totheoutsidepanelto indicatearticlesthat mayhavebeenpackaged
and shipped loose within the unit cabinet. Typically this would be a condensate pump and other
loose components that are not factory mounted.
It is the responsibility of the installing contractor to return the start-up sheet and warranty
registration card to Data Aire for proper activation of the unit warranty. Failure to do so
may cause delays in warranty related services and in some cases void the warranty.

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1.5 Storage
Your Data Aire equipment comes ready for immediate installation. In some instances it may be
necessary to store the equipment for a period of time. If you must store the equipment it should be
donein adry area,outoftheweather, innon-freezing temperatures,protected fromdamage byother
equipment in storage or transportation equipment, never stacked, and avoid frequent relocation.
CAUTION: Complete system drain-down cannot be assured for this product. Freezing
system fluid can rupture piping.
Ifequipment isstoredforlongerthan 30daysspecialprecautionsmust betakentoavoidcoildamage.
All coils should be charged and sealed with a low pressure (1-3 PSIG) inert gas, such as nitrogen.
This prevents contaminates from entering the coils; then when the seal is broken at installation, the
rushof escapinggas verifiesthecoil isstill leakfree. Ifcoils arenot chargedandsealedcondensation
mixes with air pollutants forming a weak acid and over time can cause pin hole leaks to develop in
the coil tubes.
Whenequipment isinstalledafterstoragecaution shouldbe takento inspectand replace,if required,
rubberhosesand belts. Allmovingparts,such asblowersandmotors,shouldbehandtestedto ensure
that they are free and clear prior to start-up. Finally, verify that all lubrication is fresh and full.
Itis theresponsibility oftheinstalling contractorto returnthestart-up sheetand warrantyregistration
card to DataAire for proper activation of the unit warranty. Failure to do so may cause delays and
in some cases void the warranty.
1.6 Model Identification
LCS UNITS
DAL A 06 3 2 -E -CO D
DATAAIRE LCS D – Dual compressor
UNIT S – Single compressor
A---------Air cooled
W---- Water cooled P – Package system
G----Glycol cooled
C ----Chilled water CO – Split system with
outdoor condenser (DARC)
Nominal tons
06, 08, 10 and 13 AO – Split system with
outdoor condensing unit
3 – Three phase (DRCU)
2 – 208 or 230 volt C – Auxiliary chilled water coil
4 – 460 volt E – Energy Saver
5 – 575 volt
LCS units are not available in air cooled packaged configuration.
CONDENSER – Condenser coil only, no compressor
CONDENSING UNIT – Condenser coil and compressor
The order write-up should have the condenser or condensing unit model number.
Refer to applicable condenser or condensing model number identification.
Example: DATAAIRE LCS unit, air cooled, 6 ton, 3Ø – 230 volt, split system
with outdoor condenser and dual compressors –
Evaporator model: DALA 0632 CO D Condenser model: DARC 0632

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2.0 PIPING
2.1 Split Air Cooled Unit Piping
Refer to the attached line sizing chart on page 31 for a guideline for sizing refrigerant lines. The
ultimate responsibility for line size selection is that of the installing contractor or project engineer.
DataAire does not assume this responsibility. The chart covers distances up to 200 equivalent feet.
For installations greater than this distance, consult ASHRAE or similar references.
Standardpipingpracticemustbeused toensureproperoilreturnandefficientoperation.
The interconnecting lines to the remote air cooled condenser or condensing unit must
be installed by a qualified refrigeration mechanic.
2.1.1 Discharge Lines
Discharge lines, also called hot gas lines, should be trapped at the top (inverted) and bottom, as well
as every 20 feet of vertical rise. Discharge line check valves are recommended on all installations,
especially those where there are long pipe runs or cold climate. Check valves should be installed no
less than six feet from the compressor. The discharge, suction and liquid lines need to be refrigerant
grade copper and in accordance with local code. All refrigeration piping should be installed with
high temperature brazed joints. When brazing, a supply of nitrogen gas needs to be fed through the
refrigerant lines. Be sure to open the other end of the refrigerant line to allow the nitrogen to bleed
off and not pressurize the piping. Prevailing good refrigeration practices should be employed for
pipingsupport, leaktesting,dehydration andchargingof therefrigerantcircuits. Duringtheinstallation
the lines should be capped off and filled with dry nitrogen at the end of each day’s work or until the
system is completed and sealed.
Data Aire recommends a silver/phosphorus/copper alloy with 5 to 15% silver be used to braze the
refrigerant line sets to the indoor and outdoor units. Nitrogen needs to be flowing through the lines to
eliminatecarbon depositbuildup onthe insideof thejoints. Carbon couldcontaminate therefrigerant
and restrict the metering device.
Pipingmust besupportedwithin 18”oftheinletand outletconnections. Theinlet connectionislocated
on the top header of all units. The discharge outlet is located at the bottom of the header.
Dischargelinepressuredropshouldnotexceed6PSIforR-407cand9PSIforR-410a. Recommended
gas velocity for proper oil return is 1,000 FPM. Slope horizontal lines downward in the direction of
refrigerant flow, 1/2” for every ten feet of line length. Discharge lines do not require insulation but
due to the high temperatures of the refrigerant inside the line, the pipes may be insulated to protect
against burns to individuals near or around the lines.
2.1.2 Liquid Lines
Liquid line size is determined by pressure drop and velocity. The liquid line pressure drop for R-407c
should not exceed 5 PSI or 9 PSI for R-410a. The recommended velocity should be between 200
and 300 FPM. To avoid excessive liquid line pressure drop, the air cooled condenser should be
located above or at the same level as the evaporator. Condenser installation more than ten feet
below the evaporator is not recommended. Insulation of liquid lines is not required but can be useful
in preventing condensation from forming and to avoid flashing on long pipe runs.
2.1.3 Suction Lines
Someapplications callforthe compressor(s)to bemountedas partofthecondenser,morecommonly
referred to as a condensing unit. Such cases require field piping of liquid and suction lines. Suction
lines are trapped similarly to discharge lines. Common practice for suction line selection and
installation should be followed. Suction lines should always be insulated.

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2.1.4 Connection Sizes
Air Cooled Units
Model Circuiting Hot Gas Liquid Suction
DALA 06 Single circuit 1/2” 1/2” 3/4”
DALA 08 Single circuit 3/4” 5/8” 1 1/8”
DALA 10 Single circuit 3/4” 5/8” 1 1/8”
DALA 13 Single circuit 3/4” 5/8” 1 1/8”
DALA 06 Dual circuit 1/2” 1/2” 3/4”
DALA 08 Dual circuit 1/2” 1/2” 3/4”
DALA 10 Dual circuit 1/2” 1/2” 3/4”
DALA 13 Dual circuit 1/2” 1/2” 3/4”
Field connections at the indoor evaporator and remote condenser or condensing unit
will not necessarily be the same as the field pipe size required. In some cases these
sizes will vary significantly.
Water/Glycol Cooled Units
Model Condenser Water In Condenser Water Out
DALW/G 06 1 5/8” 1 5/8”
DALW/G 08 1 5/8” 1 5/8”
DALW/G 10 1 5/8” 1 5/8”
DALW/G 13 1 5/8” 1 5/8”
Chilled Water Units with 3-Way Valves
Model Chilled Water In Valve CV
DALC 06 1” 14.0
DALC 08 1 1/4” 20.0
DALC 10 1 1/4” 20.0
DALC 13 1 1/4” 20.0
2-Way Chilled Water Units
Model Chilled Water In Valve CV
DALC 06 1” 14.0
DALC 08 1 1/4” 20.0
DALC 10 1 1/4” 20.0
DALC 13 1 1/4” 20.0
Fluid Coolers
Fluid Cooler Water IN and OUT Fluid Cooler Water IN and OUT
Model Connections, OD Model Connections, OD
DAFC 06 1 5/8” DAFC 17 2 5/8”
DAFC 07 1 5/8” DAFC 24 2 5/8”
DAFC 09 1 5/8” DAFC 28 2 5/8”
DAFC 11 2 1/8” DAFC 30 2 1/8”
DAFC 15 2 1/8”

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2.1.5 Field Piping, Remote Condenser
2.1.6 Field Piping, Remote Condensing Unit

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2.2 Water/Glycol Cooled Unit Piping
Therequired fieldinstalledcondenser waterpipe sizesmayor maynot bethesame asthe connection
sizes at the evaporator or fluid cooler. (Refer to 2.1.4 for connection sizing.) This will depend on the
length of pipe and the calculated pressure drop of peripheral components.
Water cooled units may also be connected to building water or tower water sources. Pipe size will
depend on length of run and the maximum water flow required.
Shutoff valves, field provided, should be installed within a few feet of the inlet and outlet connections
of the evaporator to allow the unit to be isolated for service. There should be a means of draining the
unit for service. Drain/fill valves should be located at the lowest point on the connected piping.
All water/glycol units are shipped with plate/fin heat exchangers as standard equipment. A strainer
is shipped loose and is to be field installed in the supply line with shut-off valves, field provided,
before and after the strainer. The strainers and water/glycol piping must be cleaned on a periodic
basis. If the unit is shipped with an optional shell and tube condenser, stainers are not required nor
shipped with the unit.
One of the most common problems in a water/glycol system is the presence of air in
the condenser water loop. Air vents must be installed in various locations in the piping
system to purge the air.
Glycol system piping may include a centrifugal pump (or pumps for redundancy). Pumps must be
primed before operating per the pump manufacturer’s guidelines.
(Field Provided)

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2.3 Auxiliary Chilled Water Coil Piping
Units with an Auxiliary Chilled Water cooling coil require a separate source of chilled water. These
chilled water connection sizes will be equal to the condenser water connection sizes on the chart in
Section2.1.4. Units withanEnergySavercooling coiltypicallyhave sharedpiping withthecondenser
supply and therefore do not require a separate water source.
All chilled water pipes have a cap installed on the end of the pipe for pressure testing the system.
These caps need to be removed before installing the water piping to the unit. Use a tube cutter for
smaller pipes and a reciprocating say with a metal cutting blade for larger pipes sizes or if there is a
clearance problem. All connections need to be cleaned before connections are brazed together.
2.4 Condensate Drain Piping
Theevaporator sectionisequipped witha3/4”FPTconnectiononthebottomfor condensateremoval.
A union is recommended at the field connection which will permit easy disconnection from the unit
for cleaning.
Atrap shouldbe builtinto thedrain lineto preventair frombacking upinto theunit. Drainlines should
be pitched downward not less than 1/4” for each ten feet of horizontal run. Do not reduce the size
of the drain line. Where local codes permit, PVC pipe may be used.
Some applications have no convenient means of allowing a gravity drain. In this case, a condensate
pump can be used. These come either factory mounted or shipped loose. Factory mounted
condensate pumps do not require a separate power source.
Condensate pumps shipped loose (or field provided) typically require a dedicated 110 volt power
source. Field pipe connections must be made to the pump discharge connection. A check valve
must be installed to prevent short cycling. See also condensate pump electrical requirements in
Section 3.9.
2.5 Humidifier Piping
The optional humidifier offered on LCSs is a steam generator type with a disposable cylinder. The
humidifier makeup water should be brought to the humidifier through the field connection opening
using 1/4” copper tubing. A compression fitting is provided at the humidifier. A shutoff valve should
be provided outside the unit to allow disconnection for service. An in-line water pressure regulator
and strainer should be installed. Water pressure should be set between 30 and 80 PSI.
The humidifier has a drain at the bottom which is factory piped to the main condensate drain line.
The dispersion tube also has a drain line. No additional field piping is required.
2.6 Dry Steam Humidifier
Units with optional dry steam type humidifiers require a strainer on the inlet steam line. An outlet
connection with field provided steam trap is also required. Steam pressure is typically 10-15 psi.

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2.7 Leak Testing
No installation is complete until the entire system has been thoroughly checked for leaks. This
includes checking refrigerant tubing, flare fittings, pressure controls, shrader fittings and compressor
rotolock service valves. Check both field and factory connections.
In addition to the refrigeration system, check all condenser water lines, humidifier makeup lines,
condensate lines, condensate pumps, chilled water lines, centrifugal pumps and fluid coolers as
applicable.
When handling and recovering refrigerant, it is not permissible to release refrigerant into the
atmosphere. Many leak-test methods recommended in the past are no longer possible. Current
standard practices must be used.
Pressurize system circuit to 150 PSIG (1034kPa) by using dry nitrogen with a trace of refrigerant.
Check the entire system for leaks with suitable leak finder, (per local code) including but not limited
to all braze joints, caps and fittings, and flare nuts on both field and factory furnished components.
After completion of leak testing, release test pressure and pull a vacuum on the system.
Tightening of fittings and valves is the responsibility of the installing contractor.
2.8 Evacuation
Evacuate the refrigerant lines, condenser coil, and evaporator coil to 250 microns or lower (a micron
gauge and 2-stage vacuum pump are required). Valve off and turn off the vacuum pump and wait for
at least 15 minutes to make sure the micron gauge reading does not go back up above 700 microns.
Ifit does,re-startthevacuumpump andevacuateuntil thesystem reaches250microns. If thesystem
still does not hold the pressure below 700 microns the system needs to be rechecked for leaks.
After the system has been satisfactorily evacuated the unit(s) can be charged with refrigerant.
Connect the pressure gauge manifold set to the high and low ports near the compressor, connect
the charging line to the refrigerant tank and set it for liquid feed. Open the refrigerant tank valve
and purge the line at the manifold, then open the high side valve on the manifold only, and allow
the refrigerant flow until the system pressure equalize, at this point the system will have 75 to 80%
of the total refrigerant charge. Start the blower and then the compressor checking the operating
pressure and temperatures.
Do not apply power to the compressor when in a vacuum.

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3.0 ELECTRICAL CONNECTIONS
Before proceeding with the electrical connections, make certain that the volts,
hertz and phase correspond to that specified on the unit electrical nameplate.
Use copper conductors only.
3.1 Electrical Service
Checkto besure theservice providedby theutility issufficienttohandletheadditionalloadimposed
by this equipment. Units with outdoor secondary heat exchangers will require a separate power
source and field-provided, interconnecting control wires as well. Indoor split units typically have a
singlepower sourcebutcanalsobe providedwithseparate sources. Field-provided,interconnecting
control wires are also required. See section 3.5 below.
Remote outdoor condensers and condensing units require one power source. Glycol systems
with fluid coolers and loose pump(s) typically require one power source for the fluid cooler and will
require one additional source for a single pump or two additional sources for dual pumps. Systems
where the pump(s) are mounted and piped integral to the fluid cooler will usually require a single
power source.
3.2 Nameplate Ratings
Refer to the unit electrical nameplate for equipment electrical requirements. Minimum Circuit
Ampacity (MCA), also known as wire sizing amps, will dictate the minimum required wire gauge.
Maximum Overcurrent Protection (MOP) Device amps will dictate the maximum circuit breaker or
fuse size.
3.3 Grounding
Theunit cabinetmusthave anuninterrupted trueearthground. An electricalgroundwireofadequate
size must be connected to the ground lug provided inside the main electrical box.
3.4 Voltage Tolerance
The supply voltage to the unit must be within tolerance; - 5% to +10% for 208-230 voltage; +10%
for 460 volts. Phase to phase imbalance must not exceed 3%. The local utility company should
be contacted for correction of improper line voltage. Deviation from ratings can cause premature
failures and possibly void unit warranty.
3.5 Auxiliary Control Wiring
For secondary heat exchangers (condensers and fluid coolers) connect two 18 gauge wires from the
electricalbox ofthe indoorevaporator tothe electricalbox ofthe remoteheat exchanger. Referto the
wiring diagrams located in the electrical box control panel of each unit. Follow the wiring diagrams
for each piece of equipment. On most remote heat exchangers the terminals will be #39 and #40.
All control wiring on Data Aire equipment is 24 VAC.
Condensing units (compressors mounted in condenser) typically require more wires. Refer to wiring
diagrams in the unit.
Check the wiring connections in the unit control panel to ensure they are tight.
Screw terminals may become loose in transit. Tightening of wiring connections is
the responsibility of the installing contractor.

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3.6 Remote Shutdown
Every Data Aire evaporator has remote shutdown contacts points available. This is intended for a
field supplied dry contact or switch to be wired across two terminals. When the contact or switch
opens, the control circuit power is interrupted and the unit shuts down, including the control panel.
The control circuit is 24 VAC and the field provided contact or switch should have a minimum rating
of 10 amps. A minimum wire size of 18 gauge wire is recommended. Check wiring diagram for
location of the terminals.
3.7 Remote Alarm Contacts
The Mini dap4 microprocessor control panel has, a remote alarm output contact that can be field
accessed on terminals #14, #15 and #16 of terminal block TB1. This is a Normally Open, Close on
Alarm, dry contact, intended to be used in a control circuit not exceeding 2 amps at 250 VAC. This
outputcontactwill reversepositionona failureandremainreversed untilthealarmis nolongerpresent.
3.8 Remote Sensors
The Mini dap4 panel comes with remote mounted sensors for field installation. The sensors are
attached to 35 feet of cable and come mounted in a remote sensor enclosure. The temperature and
humidity sensors require a total of four wires. This should be a twisted, shielded cable.
3.9 Condensate Pumps
Condensate pumps which ship loose normally require a separate source of 110 volt power. Always
check the pump power requirements before connecting power. Condensate pumps are available
in other voltages.
Condensate pumps may also come unit mounted and wired in the unit as a factory option. While no
outside power source is required, field piping is still a requirement.

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4.0 INSTALLATION OF REMOTE OUTDOOR HEAT EXCHANGER
Air cooled condensers and fluid coolers have individual Installation, Operation and Maintenance
manuals which should be referred to for more complete details.
4.1 Rigging
Thissection coversoutdoorcondensers/condensingunitsandfluidcoolers. Outdoor heatexchangers
should be moved to their (typically rooftop) mounting location using a crane or fork lift. Each fan
section has supports with lifting holes at the top.
Do not lift with a choke sling around the unit. Spreader bars are recommended for lifting multiple fan
units. Under no circumstances should the coil headers or piping be used for lifting the unit. Ideally,
the unit should be kept in its shipping crate until it is ready to be set in place.
4.2 Leg Assembly
The legs of remote heat exchanger are shipped with the unit and need to be lowered during the
riggingprocess. The legsmustbe unboltedfromtheir collapsedpositionandextendedprior toplacing
the unit on its pad. Each leg extends down 18 inches and reattached using the same bolts. The
bolts are placed through the lower set of holes on the bracket. Multiple fan units have leg supports
between each fan section.
Model number DARC-03 and DARC-05 do not have legs and are ready for installation.
Note: Failure to extend the legs will result in poor air distribution over the cooling coil
resulting in significant capacity reduction.
Concrete pads or a rail system are often used to provide support for the heat exchanger. Bolt holes
in the bottom of each leg can be used to anchor the unit.
4.3 Locating the Remote Heat Exchanger
The remote heat exchanger must be located in an area that will ensure free air flow into and out of
the heat exchanger plus adequate service access clearance. Short circuiting of the air flow or the
intake of warmer air from another unit will seriously degrade the performance of the air cooled heat
exchanger.
Donot locatethe heatexchanger ina locationthat isborderedbytallobstructions (i.e.,higher than10
feet)onnomorethantwo sides. Seefigureonnextpage forminimumclearancefromobstructionsand
between units. With proper clearance on all sides, two units can be placed side by side. Additional
units should be placed at least 48 inches apart.

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Noise factors should be also considered
when locating an air cooled heat
exchanger. Proximity to windows, walls,
and surrounding structures can cause
objectionsbythe occupants. Anacoustical
expert should be consulted when noise is
of a particular concern.
Air cooled heat exchangers should be
placed at a level that is higher than the
indoor evaporator. Mounting the remote
heatexchanger (condenserorcondensing
unit)morethan10feetbelowtheevaporator
isnot recommended. Excessiveliquidline
pressure drop can cause poor evaporator
performance.
Pipingmust besupported within18inches
of the inlet and outlet connections. The
inlet connection is located on the top
header on all remote heat exchangers and the outlet connection is located on the bottom header of
all units.
Air cooled condensers should be placed at a level that is above the level of the indoor evaporator.
Mountingacondenserorcondensingunitmorethantenfeetbelowtheevaporatorisnotrecommended.
Excessive liquid line pressure drop can cause poor evaporator performance.
4.4 Electrical Service
Refer to Sections 3.1 to 3.5 for information regarding line voltage and control voltage wiring
details.
4.5 Air Cooled Condensers - Model DARC
4.5.1 Fan Speed Control
Standard outdoor air cooled condensers have a fan speed controller on the first fan. On single-
fan condensers this is the only means of control. A variable speed controller modulates the motor
speed based on system head pressure. The fan speed controller will normally not require field
adjustment.
4.5.2 Ambient Thermostats
Additional motors (subsequent to the fan speed control operated motor) on multi-fan condensers
are cycled by ambient-sensing thermostats. These thermostats have a capillary tube with a remote
sensing bulb. They will function best if the sensing bulbs are mounted below the coil, away from
exposure to direct sunlight, with the bulb in a vertical position. An instruction set comes as part of a
mounting kit that includes a sheet metal bracket, mounting clamp(s) and TEK screws. This includes
directions for field mounting and adjusting the thermostat bulbs. Desired head pressure should be
maintained at approximately 250 psi.

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Typical settings for the ambient thermostats are as follows:
Number of fans Header fan Fan 2 Fan 3 Fan 4 Fan 5
2 FSC 65°
3 FSC 75° 65°
4 FSC 75° 85° 65°
5 FSC 65° 85° 75° 50°
4.6 Fluid Coolers - Model DAFC
4.6.1 Fluid-Sensing Thermostats
Fluid cooler fan motors are cycled on and off by individual water-sensing thermostats strapped to
the leaving water header. The first fan motor will only have a thermostat if the unit has an energy
saver coil. Without the optional energy saver coil, the first fan motor runs whenever there is a call
for cooling via an auxiliary signal sent by the indoor evaporator (see also Section 3.5).
The water-sensing thermostats have adjustable setpoints which are typically staggered to maintain
water temperature in the 85 to 105° F range. This is generally the desired range for glycol cooled
systems.
A surge tank is standard with all fluid coolers. This is sufficient for most applications. However,
an expansion tank should be installed at the highest point in the system and the point of least
pressure.
4.6.2 Energy Saver Cooling
In colder climates, the evaporator will often be equipped with an additional free cooling coil to take
advantage of the colder ambient temperatures. When incoming fluid falls below the setpoint of a
water-sensing thermostat in the evaporator (typically about 50° F), energy saver cooling becomes
available.
Systems with an energy saver coil should have at least one fluid-sensing thermostat on the fluid
cooler set lower to take advantage of colder ambient temperatures. The desired fluid temperature
for energy saver cooling is 45° F. Field adjustment of fluid-sensing thermostats is not unusual.
It is desirable to use the energy saver mode as much as possible. However, fluid temperature
that is too cold can cause excessive dehumidification and coil sweating. Fluid temperature that is
too high can also cause the indoor space temperature to rise. This could cause the evaporator’s
microprocessor control to lock out the energy saver mode for one hour while it reverts back to
compressor (mechanical) cooling. Adjust the setpoints of the thermostats to allow the maximum
free cooling time. Over cooling or under cooling the fluid should be avoided
Every application will have a different ambient temperature and indoor heat load/
air distribution profile. Therefore it is not possible to dictate the exact water-sensing
thermostat setpoints. Field adjustments are typical to allow fine-tuning to specific
conditions.

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5.0 CHARGING
5.1 Voltage Phase Check
5.1.1 Evaporator
Prior to charging, the correct voltage phasing should be checked on the indoor evaporator. Check
blower direction on the evaporator by momentarily energizing the fan motor. Reverse any two of the
three line voltage wires at the line voltage field connection point to change the blower rotation.
Although the scroll compressor is phase dependent, units shipped from the factory are run tested,
ensuringthecompressorrotationisconsistent withtheevaporator fanmotor. However, afieldchange-
out of the compressor may require checking proper phase. An out-of-phase compressor will draw
relatively low amps and both suction and discharge pressures will remain nearly equal.
5.1.2 Secondary Heat Exchanger
Thesecondary heatexchangermay beorderedas threephasebut theindividualfan motorsaresingle
phase and will only run in one direction. Check operation by placing a momentary jumper across
low voltage field terminals #39 and #40. (Disconnect pumps on glycol systems unless already filled
with water/glycol solution.) This will energize the control circuit. Fans may not run because: 1) the
thermostat setpoint is above the current ambient, or 2) the #1 fan on air cooled condensers with fan
speed control react to head pressure. The fan will not run until the head pressure is well over 200
psi.
5.2 Air Cooled Systems
5.2.1 Split Indoor Air Cooled Systems Charging
After the field refrigerant piping is properly completed, connect the refrigerant drum to the low side
and charge with vapor. Charge with approximately three lbs. per nominal ton.
For example, a model DALA 0834-COS is a nominal 8 ton single circuit unit. Charge with about 24
lbs. of refrigerant to begin. It is likely that more refrigerant will be required to complete the charging
procedure. Make sure all hoses are properly purged. Review the model number carefully because
LCS units are available with either single or dual compressors.
Before starting a compressor, the crankcase heater should be energized for a minimum
of 12 hours to reduce the possibility of liquid slugging on start-up. Failure to energize
the crankcase heater could result in compressor damage.
Start the evaporator fan and compressor. Check the liquid line sight glass to get a feel for the
approximate charge. Bubbles in the sight glass are not unusual at this point and can be caused by
flashing from liquid line pressure drop, low sub-cooling or low charge. It is likely that more refrigerant
will be required to complete the charging procedure.
Adjust the refrigerant charge until the sight glass clears or has only sparse bubbles. The unit should
be allowed to stabilize for several minutes before meaningful measurements can be taken.
A properly charged system operating at typical parameters will have a head pressure of 240 - 295
psi for R 407C and 340 - 415 psi for R 410A. Suction temperature should be 58 psi or greater for R
407C and 104 - 121 psi for R 410A. The superheat at the compressor suction line at least 6 inches
away from the compressor should be 8 - 15°.