BAC 3358C User Manual

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Fan Control
Thefollowingarefancontrolmethodstoreducingicing:
• Variable Frequency Drives:Seepage 35forinformation.
• Multi-Speed Motors:Iftheunitisequippedwith2-speedmotorsorBALTIGUARD™/
BALTIGUARDPLUS™FanSystem,operationatalowerspeedmaybesufcientto
preventicing.Themotorstartershouldincludeaminimum15secondtimedelay
whenswitchingfromhightolowspeed.
• Fan Cycling:Setthecontrolstoallowamaximumofsixon-offcyclesperhour.Cycle
thefanoffforveminutesevery15to20minutesforeachcell.Ificecontinuesto
buildontheairintake,decreasetheon-time.Observetheairintakeoftheunitatleast
everyfourtoeighthours.
• Fan Reversal:Thisprocedureshouldbeusedonlyaftertheothermethodsoffan
controlfail.Ifutilized,thefansshouldberuninreversefornolongerthan20minutes
atnomorethan50%speed,andthecoolingtowershouldbeobservedduringthis
time.Beforereturningtonormaloperation,visuallyinspectthefanbladesforice
formation.
Basin Water and Internal Piping Freeze Protection
Cold Water Basin Protection
Itisimportanttoprotectthebasinandinternalpiping.Thebasinwatercouldfreezewhen
theunitisshut-downandexposedtosubfreezingambienttemperatures.
• Remote Sump:Theidealmethodofprotectionisaremotesumplocatedinaheated
indoorspace.Whenthecirculatingpumpstops,thewaterintheconnectingpiping
willdrainbygravitytothisindoorsump.
• Basin Heaters:Onapplicationswithoutaremotesump,heatmustbeprovidedtothe
coldwaterbasin.Electricalimmersionheatersorsteamcoilscanprovidetherequired
function.ContactyourlocalBACRepresentativefordetails.
• Electric Water Level Control:Anelectricwaterlevelcontrolwillmaintaintheproper
waterlevelregardlessofthethermalloadorvariationsinmake-upwatersupply
pressure.Thetwo-position,slowclosingsolenoidvalveprovidedwiththeBACelectric
waterlevelcontrolpackagealsominimizesvalvefreezingproblems(seepage 20).
• Heat Tracing:Heattraceandinsulateallexposedwaterpipingincludingpumppiping
belowtheoverowlevelandmake-upwaterlineswithelectricalheatertape.
NOTE: Modulating the water
flow rate to the unit is NOT a
recommended method of controlling
cooling capacity.
NOTE: For remote sump
applications, the water level in
the basin of the equipment is a
function of the design flow rate,
the quantity, size and location
of the remote sump connection
and the pipe design between the
cooling tower and the remote sump.
Units installed on remote sump
applications are supplied without a
make-up connection.
Cold Weather Operation
Inspection & Maintenance
Fan Section Icing Protection
Temperature Setting
Fan Control
Basin Water and Internal Piping
Freeze Protection
Cold Water Basin Protection

BAC 3358C Specifications

General

Brand	BAC
Model	3358C
Category	Air Conditioner
Language	English