Specifications

IM 1049-4 / Page 9 of 36
Figure 11: CCH, CCW sizes 007 thru 060 (factory wired)
Figure 12: CCH, CCW Sizes 042 thru 060 (Factory wired,
460 volt motor only)
Piping
1. Allunitsshouldbeconnectedtosupplyandreturnpiping
inatwo-pipereversereturnconguration.Areverse
returnsystemisinherentlyself-balancingandrequires
onlytrimbalancingwheremultiplequantitiesofunits
withdifferentowandpressuredropcharacteristics
existinthesameloop.Checkforproperwaterbalance
bymeasuringdifferentialtemperaturereadingacross
thewaterconnections.Toinsureproperwaterow,the
differentialowshouldbe10°Fto14°F(5°Cto8°C)for
units in cooling mode.
 Adirectreturnsystemmayalsoworkacceptably,but
properwaterowbalancingismoredifculttoachieve
and maintain.
2. Thepipingcanbesteel,copperorPVC.
3. Supplyandreturnrunoutsusuallyjointheunitviashort
lengthsofhighpressureexiblehosewhicharesound
attenuatorsforbothunitoperatingnoiseandhydraulic
pumping noise. One end of the hose should have a swivel
ttingtofacilitateremovalforservice.Hardpipingcan
alsobebroughtdirectlytotheunit.Thisoptionisnot
recommendedsincenovibrationornoiseattenuationcan
beaccomplished.Thehardpipingmusthaveunionsto
facilitate unit removal. See Figure 13 for typical piping
setup.
Electrical Data
General
1. Verifythecompatibilitybetweenthevoltageandphase
oftheavailablepowerandthatshownontheunitserial
plate. Line and low voltage wiring must comply with
local codes or the National Electrical Code, whichever
applies.
2. Applycorrectlinevoltagetotheunit.A7⁄8"(22mm)hole
and/ora1-1⁄8"(29mm)knockoutissuppliedontheside
of the unit. A disconnect switch near the unit is required
bycode.Powertotheunitmustbesizedcorrectlyand
have dual element (Class RK5) fuses or an HACR circuit
breakerforbranchcircuitovercurrentprotection.Seethe
nameplate for correct ratings.
3. Threephase50cycleunits,380/50-3,requireaneutral
wirefor230/50-1powertothefancircuit.
4. Connectthethermostat/subbasewiringwiththepower
“off”totheunit.
5. Field supplied relays installed on the input terminals
W1, W2, Y1, Y2 or G may introduce electrical noise.
Never install relay coils in series with the inputs.
230 Volt Operation
All208-230voltsingle-phaseandthree-phaseunitsarefacto-
ry wired for 208 volt operation. For 230 phase operation, the
linevoltagetaponthe24volttransformermustbechanged.
Disconnect and cap the red lead wire and interchange it with
the orange lead wire on the primary of the 24 volt transform-
er(sizes007-060).
Fan Assembly
Allfanmotorsaremulti-speedPSCoroptionalECM(sizes
015-070)typewithintegralmountingbracketsandther-
mal overload protection. The motor is isolated from the
fanhousingforminimumvibrationtransmission.PSCFan
motorshaveaterminalstriponthemotorbodyforsimple
motorspeedchangewithoutgoingbacktothecontrolbox.
Tochangefanmotorspeedtohighonsize015through048,
interchangetheredwirewiththeblackwire.Forlowspeed,
sizes012,024,030,036,042and060,interchangetheblack
wire with the red wire. To change the 460 volt motor from
hightolowspeed,interchangeBlackandRedwires,then
addjumperbetweenBlackandBluewires.Allthefan/motor
assemblieshavearemovableoriceringonthehousingto
accommodate motor and fan wheel removal without discon-
nectingtheductwork.Thefanhousingprotrudesthroughthe
cabinetallowingadequatematerialforconnectionofexible
duct. Each model unit is shipped from the factory for maxi-
mum performance and minimum sound requirements. Fan
soundlevelsandperformancecanbeaffectedbyexternal
static pressure.