Specifications

ManualsBrandsYork ManualsBlower480

Solenoid 3SOL m the Ilqud IIneISnow closed and the com-

pressor pumps most 01 the rclrlgcrant out of’the evdpor:itor to

the high side of the syftcm. The sys[cm srrctIon pressure drops

until the low pressure cu[off ( 1LP) opens. This WIIIshrrt down

the compressor and de-energizesthe 12TR relay which opens

12TR-2to put the opcratlon of’the compressor under the control

of the IR relay. Also prcwnt ISa 12TR-I contact which

M closed

when the system is off and provlcfesa bypass circuit to allow con-

tactols 1Mand 2M to be actwated In the event the low pressure

cutout has not reset. Without this pumpdown cucuit, it is possible

to have the 011pressure sw[tch(OP/PS) open on IIghtload and

short cycle of the comprcwor. Refrigerant floods back to the

compressor on each start-up, foams the oil in the compressor

crankcase and pumps the oil to the condensate cod. The

run

times are too short to

bring the oIl back [o the compressor so that

eventually [he 011pressure switch opens. This rcqulres re-setting

manually at the unit.

PRE-START CHECK

Before starting the unit, the followingcheck llst should be

completed.

‘-.

10.

Make sure the proper clearances were ccmsidcred.

Makesure all foreign matter has been rcmoved from the in-

terior of the unit (tools, constructwrr or shipping materials).

Rotate all fans und blower wheels m~nually to check for free

rotation.

Check belt tensions and allgnment.

Make sureall wiring connectwns are tight.

Makesure the avadable power supply and unit nameplate

data agree.

Make sure the fuse sizes and the power wire are properly sized.

Make sureall controls arc set at their proper set points.

Makesure condensate dra]n line IStrapped pcr InstructIonsas

indicated with Figure. 4.

For shipping, the compressor hold-down nuts are

tightened, drawing the mounting feet

down to the

shipping stops. After the unit is

in its final position,

the four hold-down nuts must be removed to insert

the rubber grommets found in the small parts bag.

Replace the hold-down nuts and tighten until they

start to compress the isolator springs and then give

them an additional half turn.

INITIAL START-UP

()

; ().

SUpply power to the unit through the d]sconncLt~w][ch~1

least 8 hrs. prior to start]ng the compressors,

Movethe syste]mswitch on the thermostat or the status panel

to the AUTOposition.

The proper supply air CFM should be established at thts tlmc

with an inclined manometer as outlincd m this Instructmn.

This ISan tmportant part of”the start-up prorxxlurcsince ]t

dtrectly affects nulsancc trip-outs on unit safety controls,

corrdensatc watcr blow-off from tbc evaporator coil, bcarmg

and shaft darna~c,nolsc and vibration.

Lower the room thermostat to cncrglzc comprcswr No. 1.

With an ammeter, check the compressor and the \upply atr

blower amps to make sure they agree with the unit data plate,

Lower the room thermostat to crlergl~ecompressor No. 2. or

ioa,J the comprmsor,

(’heck [he con]prc~suramp\ w]th Ihc unit dat~ plate.

.\/ ter approx[ma[ciy 15mlnutc~()!opcru~lon,check tllc IIquId

!Irlc’)I,ghlgl:isw’~i(Jra proper \IquId Ietr]gc>lant $c’JIIn c’ac’hof

[he retrlgcl

JI)[ ~lr~utl(i)

NCX1IIILIC;IWthe wttlng 01tbc room thcrmostu[ untd the

hc~tlngcol~td~!iarc cnergl/cd.

Retcr t{)[hc

prolwr l)catlng ]r)slalldt]un and opcrallorr )n-

>[ruc( ion ~(II thc LOIIcc1 hedtlng wqucncc of opcra( Ion,

\l tcr [hc unlf ha~ bcL,n ()~cratlnti I

or wvcriil mlnu tcs. dc-

Jnc; gvc lilc md]n lpuwcIdnd lr)~pcct all 1actor} wtnng

. ,n]~cc[mIl\ dnu hol tcd ~urfacc~ Ior t lfi!)l ncii.

POST-START CHECK LIST

A\ter tllc cntlrc control clrcutt has been cncrguccil check the

following

I Cooling jystcm start-up.

2. Rotation of blower wheels. Ad]ust Ihc wr systetn If ncccssary

per the prt)ccdurcsas outlincd m thts ]nstructlon.

NOTh”: If’the supply uir blower rvta[cs it~the wr(mgdirection, -

reverse two oj” the motor lcadbat blower motor cOt~-

tact(w 3M.

Operat]on of the outside and return alr dfimpcrsa$cxplalncd

under ‘‘DamperLinkageAdjustmcrrt m th]s ]nstructton.

After the un]t ISfunctioning properly, Instruct the owner and

operator on bow to oprate the unit. Replace ail panels bclorc

Ieav}ngthe job s}tc,

MAINTENANCE

FILTERS

DRAIN PAN

The dram pan should bc mspectcd regularly to assure proper

The filters must be replaced as often as necessary to assure good

dra]nagc.

au flow and filtering action.

Refer to Figure 1 for filter accessIocatIon.

LUBRICATION

The bcar~ngsfor the blower shaft tind the blower lno~{]r~rc per-

COILS

nxrnentlv luhricated findshould not reciuirc any addIIIonal 1uhrl-

Do not allow dut to accumulate on the evaporator and condenser

catlon.

coil or other parts of the evaporator and condenser clrcu]t. Clean

BELTS

asoften as necessary to assure good system performance. Use a

Maintain belt tension to extend belt life, Rcplacc when s]gnsof

brush, vacuum cleaner attachment or other suitable means.

fadurc begtn to appear.

REFRIGERANT CHARGE R-22

–DSC300

DSC360 D.SC480

oz.

40 lb&8 OZ.

29 Ibs.d OZ, eac

h SV~

i3YORK”

HeattngandAlr Gondltlonmg

—

P O Box 1592, York PennsytvamaUSA 17405-1592

Subject10change withoutrwtme. Pmrfedm U S.A

CPC 2M t093 t 32

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