DA Data Cool Series General instructions

Data Cool
Installation, Operation and Maintenance Manual
2 and 3 ton
Air, Water and Glycol Cooled DX and Chilled Water

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CONGRATULATIONSONTHESELECTIONOFADATAAIREPRECISIONENVIRONMENTAL
CONTROLSYSTEM. PROPERINSTALLATION,OPERATIONAND MAINTENANCE OFTHIS
EQUIPMENTWILLENSUREYEARS OF OPTIMALPERFORMANCE.
This manual is intended to assist trained service personnel by providing
necessary guidelines for this particular equipment. Installation and 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.

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Table of Contents
MODEL IDENTIFICATION ........................................................................5
1.0 INSTALLATION.......................................................................................... 6
1.1 RoomConsiderations ................................................................................................ 6
1.2 Inspection .................................................................................................................. 6
1.3 Locating theUnit ........................................................................................................ 6
1.3.1 IndoorCondensingUnit.............................................................................................. 7
1.4 LevelingLegs ............................................................................................................ 7
1.5 Paperwork ................................................................................................................. 7
1.6 Storage......................................................................................................................7
2.0 PIPING........................................................................................................ 8
2.1 SplitAir Cooled Unit Piping ........................................................................................8
2.1.1 Liquid Lines ...............................................................................................................8
2.1.2 SuctionLines .............................................................................................................8
2.1.3 ConnectionSizes,AirCooled Units............................................................................ 9
2.1.4 FieldPiping, RemoteCondensing Unit....................................................................... 9
2.2 Water/GlycolCooledUnit Piping .............................................................................. 10
2.2.1 Liquid Lines .............................................................................................................10
2.2.2 SuctionLines ........................................................................................................... 10
2.2.3 ConnectionSizes,Water/GlycolCooled Units .......................................................... 11
2.2.4 ConnectionSizes, FluidCoolers .............................................................................. 11
2.3 Chilled Water Piping ................................................................................................ 11
2.4 Condensate Drain Piping......................................................................................... 11
2.5 Humidifier Piping .....................................................................................................12
2.6 LeakTesting ............................................................................................................ 12
2.7 Evacuation............................................................................................................... 12
3.0 ELECTRICAL CONNECTIONS............................................................... 13
3.1 Electrical Service .....................................................................................................13
3.2 Nameplate Ratings ..................................................................................................13
3.3 Grounding ................................................................................................................13
3.4 VoltageTolerance ....................................................................................................13
3.5 AuxiliaryControlWiring ............................................................................................ 13
4.0 INSTALLATION OF REMOTE OUTDOOR HEAT EXCHANGER .......... 14
4.1 Rigging .................................................................................................................... 14
4.2 Locating theRemoteHeat Exchanger ......................................................................14
4.3 Electrical Service .....................................................................................................14
4.4 Air Cooled Condensers - Model DRCU.................................................................... 15
4.4.1 FanSpeedControl...................................................................................................15

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Table of Contents, continued
5.0 CHARGING..................................................................................................................... 15
5.1 Voltage Phase Check............................................................................................................ 15
5.1.1 Evaporator..................................................................................................................... 15
5.1.2 SecondaryHeatExchanger............................................................................................ 15
5.2 Air Cooled Systems....................................................................................................... 15
5.2.1 SplitIndoorAir Cooled Systems Charging...................................................................... 15
5.2.2 FanSpeed ControlSystem Charging ............................................................................. 16
5.3 Water/Glycol CooledSystems ........................................................................................ 17
5.3.1 Water/GlycolCooled SystemsCharging......................................................................... 17
5.4 RefrigerantHandling ...................................................................................................... 18
5.5 ImportantRefrigerationComponents.............................................................................. 18
5.5.1 ExpansionValve ............................................................................................................18
5.5.2 HighPressure Cutout Switch ......................................................................................... 18
5.5.3 LowPressureCutout Switch .......................................................................................... 18
6.0 CONTROLS ................................................................................................................... 18
6.1 StandardThermostat...................................................................................................... 18
6.2 OptionalProgrammableThermostat............................................................................... 19
6.3 OptionalMiniDAP II Microprocessor Control Panel........................................................ 19
6.4 Optional DAP IIMicroprocessor ControlPanel ............................................................... 19
6.5 Wiring Diagrams............................................................................................................ 19
7.0 REGULAR MAINTENANCE ITEMS..............................................................20
7.1 Air Filters ....................................................................................................................... 20
7.2 Bearings ........................................................................................................................ 20
7.3 HumidifierCanisters ...................................................................................................... 20
7.4 Fuses ............................................................................................................................ 20
7.5 HeatingElements........................................................................................................... 20
7.6 RefrigerantFilterDrier ................................................................................................... 21
8.0 WARRANTY...............................................................................................22
9.0 CONTACT DATA AIRE................................................................................................ 23
Line Sizing Chart......................................................................................................................... 24
Monthly Maintenance Inspection Checklist .............................................................................. 25
Quarterly Maintenance Inspection Checklist ............................................................................ 26
INDEX .................................................................................................................................. 28 - 29

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Model Identification

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1.0 INSTALLATION
Thereis no intenton thepartof DataAire,Inc. todefinelocal codesor statuteswhichmay
supercedecommontradepractices. Themanufacturer assumes noresponsibilityfortheir
interpretation. Consult local building codes and the National Electrical Code for special
installationrequirements.
1.1 Room Considerations
Precisionairconditioningequipmentisdesignedtocontrolspaceswithinclosetolerancesoftemperature
andhumidity. However,theroommustbebuiltwithapropervaporbarrier. Afilmofpolyethyleneisoften
usedon wallsand ceilings. Walls and floors mustalso bepaintedwith a vapor-seal paint. All doorsto
thedataroomshouldbeequippedwithweathersealstopreventtheinfiltrationofnon-neutralconditioned
airfromentering the dataroom. Failureto provide avaporbarrier cancompromisetheability tocontrol
spaceconditions.
Introductionof outsideair intothe spaceshould beminimized. Outside airin excessof 5%of thetotal
circulated air volume can have a significant effect on the overall space conditions and result in poor
spacecontrol. All outsideair thatisintroducedintothespaceshouldbeconditionedtothehumidityand
temperatureparametersofthecomputerroomairconditioning(CRAC)unitsetpointstomaintainproper
roomconditionsandtopreventtheCRACunitsfromrunningexcessivelytomaintaintheroomconditions.
1.2 Inspection
ThisDataAireunithas been factory run-testedandhasgonethroughacomprehensiveinspectionprior
toitspackagingandshipmenttoensurethatitarrivesinexcellentcondition. However,shippingdamage
canoccur and avisual inspectionofthe outercrating immediately upondelivery shouldbe performed.
Noteanyexternaldamageorothertransportationdamageonthefreightcarrier’sforms. Inspecttheunit
itselfforinternaldamage. Aclaimshouldbefiledwiththeshippingcompanyiftheequipmentisdamaged
orincomplete.
Looseitemssuch asthermostat or otheroptional controlpanelsare shippedwith the unit. Referto the
manilashipping taglocated on the unit panelfor details
Freight damage claims are the responsibility of the purchaser. Actionto recoverlosses
shouldbefiled immediately withthefreight company. Refer toyellowshipping taglocatedon
theunit doorfor details
Freightdamageclaimsare theresponsibilityofthe purchaser. Actiontorecoverlosses shouldbefiled
immediately. Pleasenotifyfactory personnel ofany claims.
1.3 Locating the Unit
When installing the unit, sufficient space must be allowed for airflow clearance, wiring, plumbing and
service access. It is recommended that each side and front have a clearance of at least 12" to allow
servicingoftheunit.
Some sides may not require as much service clearance. Refer to the unit component drawings for
assistance. Rearclearance isnot required.

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NotetoInstallingContractor: Condensationformationand frequenthumidifierflushing(when
humidifier is installed) are normal functions of this equipment. Drain connections must be
made to ensure proper water removal. Unit will require drain connections for condensate
removalandwaterconnectionspossiblyforhumidifier(wheninstalled)makeupwater,chilled
waterand/or hot water. Installation ofunitsaboveequipment that couldsustain water dam-
age should be avoided.
1.3.1 Indoor Condensing Units
These24” tallsection is to be mounted using four threadedrods. Air cooledcondensing unitshave
factoryprovided ductcollars onthe supplyand intakeair openingsas appropriate. Split water cooled
condensingsections do notrequire airflowconnections.
Typical installationshave thecondensingsection physically neartheevaporator,especially since
mosthaveshared electricalline power.
1.4 Leveling Legs
EachDataCool comesequipped with fourleveling legs. Whenmounting the uniton thefloor, to
ensurethe best possibleoperation theleveling legsshould be adjustedso thatthe unitis level.
1.5 Paperwork
EachDataAireunitshipswithastart-upsheetthatmustbecompletedduringinstallation,and startupof
the unit(s). Also included in the paperwork is a warranty/information packet that provides important
wiringdiagrams,specificcomponentliterature,warranty registrationcardandothervaluablepaperwork,
includingacopyofthis Installation/Operation andMaintenancemanual.
A manila tag is attached to the outside panel to indicate articles that may have been packaged and
shippedloosewithintheunitcabinet. Thiscouldbe the thermostatorotheroptionalcontroldevicesthat
arenotfactorymounted.
Itis theresponsibility ofthe installing contractor to return the start-upsheet andwarranty registration
card to Data Aire for proper activation of the unit warranty. Failure to do so may cause delays in
warrantyrelatedservices andin some casesvoid the warranty.
1.6 Storage
YourDataAireequipmentcomesreadyforimmediateinstallation. Insomeinstancesitmaybenecessary
to store the equipment for a period of time. If you must store the equipment it should be done in a dry
area,outoftheweather,protectedfromfreezingtemperatures,protectedfromdamagebyotherequipment
instorageor transportationequipment, never stacked,and avoidfrequentrelocation.
Ifequipment is storedfor longer than30 daysspecial precautions mustbe taken toavoid coildamage.
Allcoilsshouldbechargedandsealedwithalowpressure(lessthan25psig)inertgas,suchasnitrogen.
Thispreventscontaminatesfromenteringthecoils;thenwhentheseal is broken atinstallation,therush
ofescapinggasverifiesthecoil isstillleakfree. Ifcoilsare not chargedandsealedcondensationmixes
withair pollutantsforming aweak acidand cancause pin hole leaks to develop inthe coiltubes.
Whenequipment is installedafter storage cautionshould be takento inspect andreplace, if required,
rubberhoses. Allmovingparts,suchasblowersand motors, shouldbehandtested to ensurethatthey
arefreeand clearprior to start-up. Finally, verifythat alllubricationis freshandfull.
Itis the responsibilityof theinstalling contractor toreturn thestart-up sheet andwarranty registration
cardto DataAire for proper activation ofthe unitwarranty. Failureto do so may cause delays andin
somecasesvoid thewarranty.

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2.0 PIPING
2.1 Split Air Cooled Unit Piping
Refer to the attached Line Sizing chart on page 24 for a guideline for sizing refrigerant lines. The
ultimateresponsibilityfor linesize selection isthat oftheinstallingcontractor or projectengineer. Data
Aire does not assume this responsibility. The chart covers distances up to 200 equivalent feet. For
installationsbeyond thisdistance,consult ASHRAE or similarreferences.
Standard pipingpracticemust beused toensure proper oilreturn andefficientoperation.
Theinterconnectinglines tothe remote aircooled condensingunitmust beinstalledby a
qualifiedrefrigeration mechanic.
The discharge, suction and liquid lines need to be refrigerant grade copper and in accordance with
localcode. Allrefrigerationpipingshouldbeinstalledwithhightemperaturebrazedjoints. Whenbrazing,
asupply of nitrogengas needstobe fedthrough the refrigerantlines. Be sureto open theother endof
therefrigerant line allowingthe nitrogentobleed offand not causeexcess pressurebuildup.
DataAire recommendsa silver/phosphorus/copper alloy with between5% and15% silverbe usedto
brazerefrigerantlinesettotheindoorandoutdoorunits. Nitrogenneedstobeflowingthroughthelines
toeliminate carbondeposit buildup onthe insideof thejoints whichcould contaminate therefrigerant
andrestrict the meteringdevice.
2.1.1 Liquid Lines
Liquid line size is determined by pressure drop and velocity. The liquid line pressure drop should not
exceed5 PSI. Therecommended velocityshould bebetween 200and 300FPM. Toavoid excessive
liquidlinepressuredrop,theaircooled condensing unitshouldbelocatedaboveorat the samelevelas
theevaporator. Condensingunitinstallationmorethantenfeetbelowtheevaporatorshouldbeavoided.
2.1.2 Suction Lines
Thisunithas the compressorinthe condensingunitandrequires fieldpipingof liquid andsuctionlines.
Suctionlines are trappedsimilarly to dischargelines. Common practice forsuction line selectionand
installationshouldbefollowed.

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2.1.3
Connection Sizes, Air Cooled Units
Model Liquid Suction
DACU 02 1/2" 3/4" Note: Unitwill havea LiquidLine and
DACU 03 1/2" 3/4" SuctionLine
DACU 04 1/2" 3/4"
DACU 05 1/2" 3/4"
Fieldconnectionsattheindoorevaporatorandremotecondensingunitwillnotnecessarilybe
thesame asthe fieldpipe sizerequired. In somecases thesesizes willvary significantly.
2.1.4 Field Piping, Remote Condensing Unit

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2.2 Water/Glycol Cooled Unit Piping
Therequired field installedcondenser water pipesizes mayor may notbe the sameas theconnection
sizesattheevaporatororfluidcooler. Thiswilldependonthelengthofpipeandthecalculatedpressure
dropof peripheral components.
Remotewatercooledcondensingunitsmayalso be connected tobuildingwaterortowerwatersources.
Pipesizewill dependon length ofrun andthemaximum waterflow required.
Shutoffvalvesshouldbeinstalledwithin afewfeetoftheinletandoutletconnectionsoftheevaporatorto
allowtheunittobeisolatedforservice. Afill valve with ahosebibconnectionshouldalsobeusedonthe
supplylineor returnlineat theunitto allowtheunit tobedrained.
Water/glycol cooled units with plate-fin type condensers ship with a strainer. Strainer should be field
installedon the inlet water pipe. Strainers mustbe cleanedperiodically.
2.2.1 Liquid Lines
Liquid line size is determined by pressure drop and velocity. The liquid line pressure drop should not
exceed5 PSI. Therecommended velocityshould bebetween 200and 300FPM. Toavoid excessive
liquidlinepressuredrop,theaircooled condensing unitshouldbelocatedaboveorat the samelevelas
theevaporator. Condensingunitinstallationmorethantenfeetbelowtheevaporatorshouldbeavoided.
2.2.2 Suction Lines
This unit has the compressor in the condensing unit. These cases require field piping of liquid and
suctionlines. Suction linesare trappedsimilarly to discharge lines. Common practice for suctionline
selectionandinstallation should befollowed.
One of the most common problems in a water/glycol system is the presence of air in the
condenserwaterloop. Airventsmustbeinstalledinvariouslocationsinthepipingsystemto
purgetheair, including thehighest point inthe waterloop..
Data Cool

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2.2.3 Connection Sizes, Water/Glycol Cooled Units
Evaporator Water IN and OUT
Model Connections, OD
DACW/G 02 3/4”
DACW/G 03 3/4”
2.2.4 Connection Sizes, Fluid Coolers
Fluid Cooler Water IN and OUT
Model Connections, OD
DAFC 06 1-5/8"
DAFC 07 1-5/8"
DAFC 09 1-5/8"
DAFC 11 2-1/8"
DAFC 15 2-1/8"
DAFC 17 2-5/8"
2.3 Chilled Water Piping
Unitswith ChilledWatercoolingrequireaseparatesourceofchilledwater. Thesechilledwaterconnection
sizeswill be equalto thecondenser waterconnection sizeson the chartin Section2.2.3.
2.4 Condensate Drain Piping
Theevaporatorsection isequippedwith a 3/4"FPT connection onthebottom forcondensateremoval.
Aunion isrecommended at the field connectionwhich willpermit easy disconnection from theunit for
cleaning.
Atrapshouldbebuiltintothedrainlinetopreventair from backing upintotheunit. Drainlinesshouldbe
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
pumpcanbeused. Thesecomeeitherfactorymountedorshippedloose. Factorymountedcondensate
pumpsdo notrequire aseparate powersource andthe alarmswitch iswired tothe controlsystem.
Condensatepumpsthatarenotfactorymountedshiploose(orfieldprovided)typicallyrequireadedicated
110 volt power source. Always check the pump power requirements before connecting power. Field
pipeconnections must bemade tothepump dischargeconnection. Acheckvalve mustbe installedto
preventshortcycling.

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2.5 Humidifier Piping
Theoptionalhumidifier offeredon DataCool is asteam generatortypewith adisposablecylinder. The
humidifiermakeupwatershouldbebroughtto the humidifier throughthefieldconnectionopeningusing
1/4"coppertubing. Acompressionfittingisprovidedatthehumidifier. Ashutoffvalve shouldbeprovided
outside the air conditioner to allow disconnection for service. An in-line water pressure regulator and
strainershould beinstalled. Water pressureshould beset between30 and 50 PSI.
Thehumidifier hasa drainat thebottom whichis factorypiped to the main condensate drain line. The
dispersion tube also has a drain line. No additional field piping is required.
2.6 Leak Testing
Noinstallationiscompleteuntil the entiresystemhasbeenthoroughlychecked for leaks. Thisincludes
checking refrigerant tubing, flare fittings, pressure controls, shrader fittings and compressor rotolock
servicevalves.
Inadditiontotherefrigerationsystem,checkallcondensate lines,humidifier makeup lines,condensate
lines,condensate pumps, chilledwater lines,centrifugalpumps andfluid coolersasapplicable.
Whenhandlingandrecoveringrefrigerant,itisnotpermissibletoreleaserefrigerantintotheatmosphere.
Manyleak-test methods recommendedin thepast are nolonger possible. Currentstandard practices
mustbeused.
Oneacceptablemethodof leaktestingaircooled systems doesnotinvolvethe useofrefrigerant. Prior
tocharging,pressurize thesystemto 150psiwith drynitrogenwith allrefrigerantvalves open. Placea
gaugeon the lineand allowat leastfour hours beforeobserving ifthe pressurereading has changed.
Tightening of fittingsand valves istheresponsibility oftheinstallingcontractor.
2.7 Evacuation
Itisoftheutmostimportancethatpropersystemevacuationandleakdetectionproceduresbeemployed.
DataAire recommends a minimum evacuation to 500 microns. Good evacuation processes include
frequent vacuum pump oil changes and large diameter, short hose connections to both high and low
sides of the system preferably using copper tubing or bronze braided hose. If the compressor has
service valves, they should remain closed. Adeep vacuum gauge capable of registering pressure in
microns should be attached to the system for pressure readings. Ashut-off valve between the gauge
connection and vacuum pump should be provided to allow the system pressure to be checked after
evacuation.Donotturnoffvacuumpumpwhen connected to anevacuatedsystembeforeclosingshut-
offvalve.
Donot apply powerto thecompressor when ina vacuum.

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3.0 ELECTRICALCONNECTIONS
Beforeproceeding with the electrical connections, make certainthatthe volts, hertz
and phase correspond to that specified on the unit electrical nameplate. Units
damaged from incorrect power input will not be covered under warranty. Use
copper conductors only.
3.1 Electrical Service
Checkto besure theservice provided by the utilityis sufficientto handlethe additionalload imposed
by this equipment. Indoor unit has a single power source. Indoor split units typically have a single
powersourcebutcan also beprovidedwithseparatesources. Field-provided, interconnectingcontrol
wiresare also required. Unitswith outdoorsecondary heatexchangers will requirea separatepower
sourceand field-provided,interconnecting control wiresas well. Seesection 3.5below.
Remote outdoor 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
mountedand piped integralto thefluid cooler willusually requirea singlepowersource.
3.2 Nameplate Ratings
Refertotheunitelectricalnameplateforequipmentelectricalrequirements. MinimumCircuitAmpacity,
alsoknownasWireSizingAmps,willdictatetheminimumrequiredwiregauge. MaximumOvercurrent
ProtectionDevice ampswill dictatethe maximumcircuit breakeror fusesize.
3.3 Grounding
Theunitcabinet musthave an uninterruptedtrue earth ground. Anelectrical ground wireof adequate
sizemust beconnected to theground lugprovided insidethe mainelectrical box.
3.4 Voltage Tolerance
Thesupplyvoltagetotheunitmustbewithintoleranceof-5%+10%for208-230voltage,+/-10%for460
voltage. Thelocalutilitycompanyshouldbecontactedforcorrectionofimproperlinevoltage. Deviation
fromvoltage ratings cancause prematurefailuresand possiblyvoid unit warranties
Check the wiring connections in the unit control panel to ensure they are tight. Screw terminals may
comeloose in transit. Tightening ofwiring connections isthe responsibilityof the installingcontractor.
3.5 Auxiliary Control Wiring
Theoutdoorcondensingunit requiresitsown powersource andground source. Adisconnect(field
provided)is requiredto beinstalled to isolate the unit for maintenanceand service. Check
nameplatevoltage ratings toensure fieldpower(building power).
Afield supplied 3 or 4 wire control connection (24 VAC) is required between the evaporator and the
condensing unit. All control wiring must be installed in accordance with the National Electrical Code
(NEC)Class 1circuit. See the unit schematic forcontrol wiringdetails
Check the wiring connections in the unit control panel to ensure they are tight. Screw
terminalsmaybecomelooseintransit. Tighteningofwiringconnectionsistheresponsibility
oftheinstallingcontractor.

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4.0 INSTALLATION OFREMOTEOUTDOOR HEATEXCHANGER
4.1 Rigging
This section covers outdoor condensing units and fluid coolers. Outdoor heat exchangers should be
moved to their (typically rooftop) mounting location using a crane or fork lift. Each fan section has
supportswithlifting holesat the top.
Do not lift with a choke sling around the unit. Spreader bars are recommended for lifting multiple fan
units. Undernocircumstancesshould the coilheaders orpipingbe usedforliftingthe unit. Ideally, the
unit should be kept in its shipping crate until it is ready to be set in place.
Concretepadsorrailsareoftenusedtoprovidesupportfortheheatexchanger. Boltholesinthebottom
ofeach leg canbe usedto anchorthe unit.
4.2 Locating the Remote Heat Exchanger
Consultlocal codesor ordinances for restrictions regardinglocation ofunit.
Selectalocation fortheunit whereiceand snowwillnot fallfroman overhanganddamage theunittop
orfan blade. Caremust beexercised tomaintain theclearance requirements.
Aircooledcondensing unitsshould beplaced at alevel that isabove the levelof the indoorevaporator.
Mountinga condensing unitmore thanten feetbelow the evaporatoris notrecommended. Excessive
liquidline pressuredrop cancause poorevaporator performance.
Seedimensional drawings forthe following:
1. Locationof refrigerationand electricalconnections
2. Recommendedclearances
3. Directionof condenserairflow
4. Mountingbase dimensions
Placeunitonlevelbasestrongenoughtosupporttheweightoftheunitandresisteffectsoffrostheaving,
etc. Concretelintels canbe usedif spacedto adequatelysupport unit.
Allowairtocirculateunderunit. Channelsareprovidedforthispurposeorunitmaybesetinabituminous
mixturesuch as roofingtar toprevent base panfrom rusting. Donot plugdrainholes.
On rooftop applications, locate unit at least 6 inches above roof surface. Where possible, place unit
above load-bearing wall. Arrange supporting members to adequately support unit and minimize
transmissionofvibration tobuilding. Precast concrete lintels,concrete blocks, treatedtimbers orsteel
beams can be used. Consult local code governing rooftop applications. In cold climates locate unit
aboveexpectedsnow levels.
Avoidlocationswhereflowers,shrubs,etc.areinthepathwayofcondensingunit air discharge orwhere
thecondensing fan willdischarge against prevailingwind ora building structure.

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4.3 Electrical Service
Referto Sections3.1 to3.5 forinformation regarding line voltage and control voltagewiring details.
4.4 Air Cooled Condensing Unit - Model DRCU
4.4.1 Fan Speed Control
Standardoutdoorair cooled condensingunitshaveafanspeedcontrolleronthe first fan. Onsingle-fan
condensing unit this is the only means of control. A variable speed controller modulates the motor
speedbasedonsystemheadpressure. Thefanspeedcontrollerwillnormallynotrequirefieldadjustment.
5.0 CHARGING
5.1 Voltage Phase Check
5.1.1 Evaporator
Priorto charging, thecorrect voltagephasing shouldbe checkedon the indoorevaporator. Check
blower direction on the evaporator by momentarily energizing the fan motor. Reverse any two of the
threeline voltage wiresat thelinevoltage fieldconnection point tochange theblower rotation.
Althoughthe scrollcompressor isphase dependent,units shippedfrom the factory are run tested,
ensuringthecompressorrotationisconsistent with theevaporatorfanmotor. However, afieldchange-
outthecompressormayrequirecheckingproperphase. Anout-of-phasecompressorwilldrawrelatively
lowamps and bothsuction anddischargepressures willremain nearly equal.
5.1.2 Secondary Heat Exchanger
The secondary heat exchanger may be ordered as three phase but the individual fan motors are
singlephaseand willonlyrun inonedirection.
5.2 Air Cooled Systems
Beforestartingacompressor, thecrankcaseheater shouldbe energizedfora minimumof
12 hours to reduce the possibility of liquid slugging on start-up. Failure to energize the
crankcaseheater couldresult in compressordamage.
5.2.1 Split Indoor Air Cooled Systems Charging
Afterthefield refrigerantpiping is properlycompleted, connect therefrigerant drumtothe lowsideand
chargewithvapor. Chargewith approximatelythreelbs. pernominalton.
Forexample,amodel DACU0334-AOisa nominal3tonunit. Charge with about9lbs. of refrigerantto
begin. Itis likely thatmore refrigerantwill berequired to completethe chargingprocedure. Make sure
allhoses are properlypurged.
Beforestartingacompressor,thecrankcase heater shouldbeenergized for aminimumof
12 hours to reduce the possibility of liquid slugging on start-up. Failure to energize the
crankcaseheater couldresult in compressordamage.

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Starttheevaporatorfanandcompressor. Checktheliquidlinesightglasstogetafeelfortheapproximate
charge. Bubblesinthesightglassarenot unusual at thispointandcanbecausedbyflashingfromliquid
line pressure drop, low sub-cooling or low charge. It is likely that more refrigerant will be required to
completethecharging procedure.
Adjusttherefrigerantcharge untilthesightglass clearsorhasonly sparsebubbles. Theunitshould be
allowedtostabilize forseveralminutes beforemeaningful measurements canbe taken.
Aproperlycharged system operatingattypical parameters willhavea head pressureof225 to275psi.
Suctionpressure should be58 psior greater. The superheat atthe compressor suctionline at least6
inchesaway from thecompressor shouldbe 8-15°.
Note: Chargingtoafullliquidlinesightglassshouldneverbethesolemeansofdetermining
the correct refrigerant charge. Other parameters such as superheat, suction pressure,
headpressure, sub-coolingand ambient temperature are alsoimportantparameters. A
systemcharged toa clearsight glassis oftenovercharged.
5.2.2. Fan Speed Control System Charging
The standard outdoor air cooled condensing for DataAire equipment is a fan speed control system.
Afterthefieldrefrigerant piping isproperlycompleted,connect the refrigerantdrumtothe lowsideand
chargewithvapor. Chargewith approximatelythreelbs. pernominal ton plusthe line set.
Forexample, amodel DCAU0334-AO isa nominal3 tonunit. Charge withabout 9lbs. ofrefrigerant
to begin. It is likely that more refrigerant will be required to complete the charging procedure. Make
sureall hoses areproperly purged.
Beforestartinga compressor,if the systemhas a refrigerantholding charge, thecrankcase
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. If the system is charged and started from a vacuum, the preheating of the
compressoris notnecessary.
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
flashingfrom liquidline pressuredrop, lowsub-cooling or low charge. It is likely thatmore refrigerant
willbe requiredto complete the charging procedure.
Adjust the refrigerant charge until the subcooling is between 8° F and 10° F and the superheat is
between 8° F and 15° F. There may be flashing and/or bubbles in the sight glass when the system is
properly charged. The unit should be allowed to stabilize for several minutes before meaningful
measurementscanbe taken.
Afterthe system isallowed tostabilize, verificationof a fewkey measurementsshould benoted. The
discharge pressure should be between 225 to 275 psi and the sub-cooling should be 8-10 degrees,
dependingonambientconditions. Suctionpressureshould be 58psiorgreater. Thesuperheat atthe
compressorsuction lineat least6 inchesaway fromthe compressorshould be 8-15 degrees.
Note: Chargingtoafullliquidlinesightglassshouldneverbethesolemeansofdetermining
the correct refrigerant charge. Other parameters such as superheat, suction pressure,
head pressure, sub-cooling and ambient temperature are also important parameters. A
systemcharged toa clearsight glassis oftenovercharged.

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5.3 Water/Glycol Cooled Split Systems
5.3.1. Water/Glycol Cooled Split Systems Charging
Allwater/glycolData Cool unitsaresplitsystems requiring fieldcharge. Aftertherefrigerantpiping and
water line piping is properly completed, connect the refrigerant drum to the low side and charge with
vapor. Charge withapproximatelythree lbs. pernominal ton.
Forexample,amodel DACU0334-AOisa nominal3tonunit. Charge with about9lbs. of refrigerantto
begin. Itis likely thatmore refrigerantwill berequired to completethe chargingprocedure. Make sure
allhoses are properlypurged.
Beforestartingacompressor,thecrankcase heater shouldbeenergized for aminimumof
12 hours to reduce the possibility of liquid slugging on start-up. Failure to energize the
crankcaseheater couldresult in compressordamage.
Starttheevaporatorfanandcompressor. Checktheliquidlinesightglasstogetafeelfortheapproximate
charge. Bubblesinthesightglassarenot unusual at thispointandcanbecausedbyflashingfromliquid
line pressure drop, low sub-cooling or low charge. It is likely that more refrigerant will be required to
completethecharging procedure.
Adjusttherefrigerantcharge untilthesightglass clearsorhasonly sparsebubbles. Theunitshould be
allowedtostabilize forseveralminutes beforemeaningful measurements canbe taken.
Aproperlycharged system operatingattypical parameters willhavea head pressureof225 to275psi.
Suctionpressure should be58 psior greater. The superheat atthe compressor suctionline at least6
inchesaway from thecompressor shouldbe 8-15°.
Note: Chargingtoafullliquidlinesightglassshouldneverbethesolemeansofdetermining
thecorrectrefrigerantcharge. Otherparameterssuchassuperheat,suctionpressure,head
pressure,sub-cooling and ambienttemperature arealsoimportantparameters. Asystem
chargedto aclear sightglass isoften overcharged.
The water regulating valve should be adjusted to maintain 230 to 260 psi head pressure. Suction
pressure should be 58 psi or greater. The superheat at the compressor suction line at least 6 inches
awayfrom the compressorshould be8-15°.
Itisnecessarytomeasureandnoteproperunitoperationincludingsuperheat,headandsuctionpressure.
Someadjustment tocharge may berequired.
Adjust the refrigerant charge again until the sight glass clears or has only sparse bubbles. The unit
shouldbeallowed tostabilize for severalminutes before meaningfulmeasurements can betaken.
All water/glycol cooled units have a water regulating valve. A head pressure sensing transducer is
connected to a shrader fitting on the discharge line and water is regulated into the condenser coil.
Condensercoils maybe platefin orcoaxial type.

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5.4 Refrigerant Handling
Theuseofrecovery/recyclingunitsisrequiredbyU.S.EnvironmentalProtectionAgency(EPA)regulations.
Technicianswhoservice anddispose ofair conditioning andrefrigeration equipmentmust recoverthe
refrigerantinsteadof ventingtoatmosphere.
Except for extremely small releases of refrigerant such as what occurs when disconnecting service
hoses(diminutiverelease),atechnician who knowinglyreleasesorventsrefrigerant to theatmosphere
is in violation of these regulations. Freon purchasers must be certified technicians and have a valid
EPAcertification card.
5.5 Important Refrigeration Components
5.5.1 Expansion Valve
Eachrefrigerantcircuithasanadjustablethermo-expansionvalve (TXV). These are factoryadjustedto
theirnominalrating. Anyfieldadjustmentshouldbetofinetuneasystemthathasstabilizedand already
hasacceptable operatingparameters.
5.5.2 High Pressure Cutout Switch
Eachrefrigerant circuitis protectedby ahigh headpressure cutoutswitch witha manualreset button.
The cutout pressure rating for refrigerant R-22 is 400 psi. Physical location is near the compressor
whichmay be eitherin theevaporatoror thecondensing section.
5.5.3 Low Pressure Cutout Switch
Eachcircuitalsocontainsalowsuctionpressurecutoutswitchwithautomaticreset. Thecutoutpressure
rating for this switch is 30 psi. Physical location is near the compressor which can be either in the
evaporatororthe condensingsection.
6.0 CONTROLS
6.1 Thermostat
Each Data Cool unit is shipped with a cooling only digital thermostat designed to provide accurate
control,displaysroomtemperatureand cooling onmode. Thesixbuttonson thefrontofthethermostat
allowcompletecontrol of theequipment.
Setpoints- Raisingand loweringthe setpointsis accomplished by simply pushingthe “Up” or“Down”
buttons. Theunitwill display eitherFahrenheitor Celsius.
Cooling - Select the temperature by pressing the “Up” or “Down” button. The word “COOL” and the
temperaturesetting isDisplayed forfive seconds.
Fahrenheit/Celsius-Simultaneously pressthe“Up” and“Down”buttons toswitch between Fahrenheit
andCelsiustemperature setpoint.
Followthe providedwiring diagram.

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6.2 Programmable Digital Thermostat
Acooling only digitalthermostat designedto provide accuratecontrol, displaysroom temperature and
coolingonmode. The buttonsonthe front ofthethermostat allowcompletecontrol of theequipment.
Cooling - Select the temperature by pressing the “Up” or “Down” button. The word “COOL” and the
temperaturesetting isdisplayed forfive seconds.
Fahrenheit/Celsius-Simultaneously pressthe“Up” and“Down”buttons toswitch between Fahrenheit
andCelsius temperature setpoint.
In addition, the thermostat can be programmed for two or four events per day. The events will allow
programofaday andnightsetting. Foureventswillallow programmingofamorning, day, eveningand
nightsettings. See theenclosed booklet(Uni-Line 110-809C)for programming details.
Followthe providedwiring diagram.
6.3 Optional Mini DAP II Microprocessor Control Panel
The Mini DAP II microprocessor control panel is an optional control panel available as an upgrade to
thethermostat. Thereisaseparatemanualthatgoesintoextensive detail regarding functions, features,
programmingandtroubleshooting.
The Mini DAP II microprocessor control panel has an entire manual dedicated to its use
andoperation. This manualmust be referenced to complete a thoroughunit installation.
Start-up isnotcomplete untilthe MiniDAPIIcontrol panelsettings areestablished.
6.4 Optional DAP II Microprocessor Control Panel
TheDAPII microprocessorcontrolpanel isavailableas anupgradeto the MiniDAP II paneland offers
additional features including remote communications (with additional communication card options).
Thereisa separatemanualthat goesintoextensive detailregardingfunctions, features,programming
andtroubleshooting.
The DAP II microprocessor control panel has an entire manual dedicated to its use and
operation. Thismanualmustbereferencedtocompleteathoroughunitinstallation. Start-
upis not completeuntil theDAPII controlpanel settingsareestablished.
6.5 Wiring Diagrams
Every DataAire evaporator and condensing unit or fluid cooler comes with a wiring diagram. These
diagramsare‘ladder’-typeschematicsintendedforservicepersonnel. Theintentistoallowthetechnician
tounderstandthe wiringdetailsassociated with the electricalcomponentsand howtheyinterface with
thecontrolsas well asperipheralequipment, includingsecondaryheat exchangers.

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Thewiringdiagramintheevaporatorwillindicatefieldinterfaceterminalstothesecondaryheatexchanger.
The internal wiring of the heat exchanger is found on a separate diagram which can be found on the
insidecoveroftheheatexchangerelectricalbox. Bothdiagramtypesarealsoplacedinsidetheshipping/
warrantypacketthat isplaced insidethe evaporator.
Evaporatorwiringdiagramswillhaveadrawingnumberwhichstartsoutwiththethreeletterdesignation,
“DCX”. Thewiring diagramfor theData Cool is DCX-S-776. Wiring diagrams for thecondensing unit
start out with the three letter designation, “DRC”. An example of a typical diagram is DRC-S-001.
Wiring diagrams for fluid coolers start out with the three letter designation, “DFC”. An example of a
typical diagram is DFC-S-001.
7.0 REGULARMAINTENANCEITEMS
7.1 Air Filters
Airfilters should bechecked onaregular basisand changed whenthey becomedirty. Thiswill ensure
efficient operation of the unit. Spare air filters should be kept in stock as these tend to be a frequently
replaced maintenance item. Air filters may require changing as often as monthly. Note also that
constructiondustonnew installations willquicklyclognew filters.
Airfiltersthatrequirechanging canrestrictairflowandcreate problems suchascoilicing or
poorair distribution.
7.2 Bearings
Blowerbearings used onData Coolunits are permanentlylubricated anddo not requiremaintenance.
7.3 Humidifier Canisters
The optional steam generator type humidifier does not require maintenance other than to replace the
canister as required. This frequency will depend on usage and water type. A set of manufacturer’s
instructionsfor thehumidifier issent as part of thepaperwork placedinside theunit whenit ships.
7.4 Fuses
Fusesmayoccasionallyrequirechangingespeciallywithinstallationswherethevoltageisnotconsistent.
Drops in voltage can create brief periods of high amp draw, causing fuses to blow. Always replace
fuses with those of the equivalent rating with regard to: 1) amperage, 2) voltage, and 3) speed. For
instancecompressors andmotors are inductive loads which require timedelay fuses. Electricreheat
andhumidifiers areresistive loadsrequiring fastacting fuses.
7.5 Heating Elements
The optional heating elements do not normally require maintenance. However sometimes they may
accumulateafilmofdustordirtwhenunusedforextendedperiodsoftime. Whenenergized,theburning
debriscan create smoke or unpleasant odor. Tohelp avoid this, periodic cleaning isrecommended.