Trane QFNA-IOM-1 Fan User Manual


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Start-UpProcedures
Thefollowingitemsmustbe
checkedbeforeinitialstart-upof
thefan:
1. Checkallbolts,setscrews,and
lockingcollarsonthefan,
bearings,drive,motormount,and
accessoriesfortightness.See
Tables4,5,10,11and13.
2. Turnthefanwheelbyhandtobe
sureitdoesnotstrikeanyportion
ofthehousing.SeeTable3fortip
clearancefortipclearance.
3. Recheckbearingalignmentand
lubrication.
4. Operatethevariableinletvanes
tobesuretheymovefreelyand
positionproperly.
5. Repairanycoatingflawsinunits
withspecialprotectivecoatings.
6. Checkswitchesandwiringto
motor.
7. Checkfanandductfordirtand
debrisandcloseallaccessdoors.
Foreignmaterialintheinletcone
cancausewheelimbalance.
8. Checkbeltalignmentandtension
asfollows:
• Tightenthebeltsslightlyand
manuallyrotatethedriveseveral
times.
• Onmultiplebeltdrives,determine
thattheforceofdeflectionis
approximatelythesameby
pushingeachbeltinanequal
distanceatapointhalfwayfrom
eachsheave.Ifthisforceisnot
thesameforeachbelt,themotor
andfanshaftarenotparallel.
Realignasrequired.
• Afterrealignment,tightenthebelts
againtoareasonabletension.
• Operatetheunitafewminutesto
allowbeltstoseat.Beltsshould
notslipwhenrunning,butaslight
squealatstart-upisnormal.DO
NOTOVER-TENSIONBELTS.
• Belttensionshouldberechecked
after8hoursofoperationand
monthlythereafter.Whenthebelt
isinoperation,thetightsideof
thebeltshouldformastraightline
fromsheavewithonlyaslightbow
ontheslackside.
Atinitialstart-up,checkthefanwheel
forproperrotation.Whenfacingthe
inlet,thewheelmustrotate
clockwise.
Ifthefanhasinletvanes,theycanbe
partiallyclosedtolowerpower
requirementsatstart-up.Onfans
withmulti-speedmotors,runinitial
checkoutatlowspeed.
Payparticularattentiontoany
vibration,noiseoroverheatingofthe
fanbearingsandmotor(bearings
mayrunwarmduringbreakin).
Vibrationisthemostcommon
problemencounteredduringstart-up.
Ifthevibrationissignificant,itmust
becorrectedbeforeallowingthefan
tooperatecontinuously.SeeTable8.
The“TroubleShooting”sectionof
thismanualdetailsthecommon
causesforvibration.Iftheproblemis
diagnosedasfanwheelimbalance,
useavibrationanalyzertorebalance
thefan.Theadditionofanybalance
weightscanbemadeontheinlet
cone.SeeFigure11.
DeterminingFanRPM
QFansandSuperIIFanswith
factoryinstalledmotoranddriveare
shippedwiththecorrectFanRPM.
However,ifthemotoranddriveare
fieldinstalledandtheFanRPM
needstobesetorchecked,the
followingprocedurecanbeused:
FanRPMcanbestbedeterminedby
usingastrobe-typetachometer.If
suchaninstrumentisnotavailable,
approximateRPMcanbederivedas
follows:
1. Removebeltguardandmark
motorsheave.
2. Byhand,rotatethefanwheel10
timeswhilecountingrevolutions
ofmotorsheavetothenearest
quarterturn.
3. DividethenameplatemotorRPM
bythenumberofrevolutionsof
themotorsheaveandmultiplyby
10.ThisisFanRPM.
Example: Ifmotorsheaverevolves
8-1/4turns--Motornameplate
states1750RPM.
20 QFNA-IOM-1
Start-UpQFansandSuperQII
Table8-MaximumAllowableVibrationonTraneModelQFans
FanSize FanRPM Vert,Horiz,andAxial
Fans
16-44 AllSpeeds 5Mils
49-60 Upto1000 4Mils
49-60 1000&Up 3Mils
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