Lennox 10ACC Series Installation and operation manual

Page 1 ã2002 LennoxIndustriesInc.
Litho U.S.A.
Corp.0201-L1
10ACC
Service Literature
10ACC SERIES UNITS
The 10ACC isaresidentialsplit-systemcondensing
unitavailableinsizesrangingfrom1-1/2to5tons.Con-
densing coil size,circuiting and airvolumeresultin a
minimumSEERrating of10.0.The seriesisdesigned
forusewith an expansion valve orRFCIVsysteminthe
indoorunit.
10ACC 1-1/2to3ton unitsare equipped withreciprocating
compressors.All compressorsare hermetically sealed for
long servicelife.The compressorisinstalled inthe uniton re-
silientrubbermountsto assure quiet, vibration-free operation.
Abuilt-in protection device assuresprotection fromexcessive
currentand temperatures.
10ACC3-1/2to5tonunitsareequippedwithscrollcom-
pressors.Thescrolloperateslikeastandardcompressorbut
itisunique inthe wayitcompressesrefrigerant.
WARNING
Refrigerantcan beharmful ifitisinhaled.Refriger-
antmustbeusedand recoveredresponsibly.
Failuretofollowthiswarning may resultin person-
al injuryordeath.
WARNING
Electric shock hazard.Cancause injury
ordeath.Before attempting to perform
any service ormaintenance,turnthe
electricalpowerto unitOFF atdiscon-
nectswitch(es).Unitmay have multiple
powersupplies.
Thismanual isdivided intosectionswhich discuss the
majorcomponents,refrigerantsystem,charging proce-
dure,maintenance and operation sequence.
All specificationsinthismanualaresubject tochange.
IMPORTANT
Improperinstallation,adjustment,alteration,ser-
vice ormaintenance cancause propertydamage,
personal injuryorloss oflife. Installation and ser-
vice mustbeperformed by a qualifiedinstalleror
service agency.

Page 2
ELECTRICALDATA
General
Data
ModelNo.10ACC-018
-230
10ACC-024
-230
10ACC-030
-230
10ACC-036
-230
10ACC-042
-230
10ACC-048
-230
10ACC-060
-230
Line voltage data-60hz208/230v-1ph 208/230v-1ph 208/230v-1ph 208/230v-1ph 208/230v-1ph 208/230v-1ph 208/230v-1ph
Rec.maxfusesize(amps)20 25 30 35 40 50 60
¡Minimumcircuitampacity11.6 14.3 17.3 20.4 23 31.2 35.5
CompressorRated load amps8.6 10.8 12.9 16.2 17.9 21.8 25
Locked rotoramps48.3 60 69.4 96 103 131 170
Powerfactor0.97 0.96 0.92 0.90 0.84 0.80 0.90
Condenser
F
a
n
M
o
t
o
r
Full load amps0.8 0.8 1.1 1.7 1.9 1.9 0.9
F
a
n
M
o
t
o
r
Locked rotoramps1.2 1.2 1.9 3.1 4.1 4.1 4.1
¡RefertoNationalorCanadian Electrical Code manualto determine wire, fuse and disconnectsizerequirements.
NOTE—Extremesofoperating range are plus10%and minus5%ofline voltage.
SPECIFICATIONS
General
D
a
t
a
ModelNo.10ACC-018 10ACC-024 10ACC-030 10ACC-036 10ACC-042 10ACC-048 10ACC-060
G
e
n
e
r
a
l
DataNominalTonnage (kW)1.5(5.3)2(7.0)2.5(8.8)3(10.6)3.5(12.3)4(14.1)5(17.6)
Connections
(
s
w
e
a
t
)
Liquidline (o.d.) - in.(mm)©3/8(9.5)©3/8(9.5)3/8(9.5)3/8(9.5)3/8(9.5)3/8(9.5)3/8(9.5)
C
o
n
n
e
c
t
i
o
n
s
(sweat) Suction line (o.d.) - in.(mm)5/8(15.9)5/8(15.9)3/4(19.1)3/4(19.1)7/8(22.2)7/8(22.2)1-1/8(28.6)
Refrigerant*HCFC-22 charge furnished 4 lbs.13 oz.
(2.18 kg)4lbs.13 oz. (2.18 kg)4lbs.1 oz. (1.8kg)4lbs.13 oz. (2.18 kg)5lbs.4 oz. (2.38 kg)6lbs.3 oz. (2.81 kg)8lbs.5 oz. (3.77 kg)
Condenser
C
o
i
l
Net face area -sq. ft. (m2)OuterCoil 9.24 (0.86)9.24 (0.86)10.46 (0.97)11.41 (1.06)13.31 (1.24)15.11 (1.40)20.83 (1.94)
C
o
n
d
e
n
s
e
r
Coil InnerCoil --- --- --- --- --- 5.4(0.50) - - -
Tube diameter - in.(mm)5/16 (7.9)5/16 (7.9)5/16 (7.9)5/16 (7.9)5/16 (7.9)5/16 (7.9)5/16 (7.9)
No.ofrows1 1 1 1 1 1.37 1
Finsperinch(m)22 (866)22 (866)18 (709)22 (866)22 (866)22 (866)22 (866)
Condenser
F
a
n
Diameter - in.(mm)16 (406)16 (406)18 (457)18 (457)18 (457)18 (457)22 (559)
C
o
n
d
e
n
s
e
r
FanNo.ofblades3 3 3 3 4 4 4
Motorhp (W)1/10 (75)1/10 (75)1/6(124)1/4(187)1/3(249)1/3(249)1/3(249)
Cfm(L/s)1730 (815)1730 (815)2170 (1025)2510 (1185)2800 (1320)2950 (1390)3900 (1840)
Rpm1070 1070 1100 1103 1116 1100 1100
Watts184 184 254 266 299 310 367
Shipping weight (1package)lbs.(kg)107 (49)107 (49)136 (62)140 (64)140 (64)196 (89)199 (90)
OPTIONALACCESSORIES-MUSTBEORDEREDEXTRA
Crankcase Heater68887 68887 68887 68887 90P12 90P12 90P12
Hail Guards 17L71 17L71 17L71 17L73 17L73 17L73 17L73
LowAmbientKit (forExpansion Valve systemsonly)24H77 24H77 24H77 24H77 24H77 24H77 24H77
Mounting
B
a
s
e
ModelNo.MB2-S(69J06)
M
o
u
n
t
i
n
g
Base NetWeight6lbs.(3kg)
B
a
s
e
Dimensions-in.(mm)22-1/4x22-1/4x3(565 x565x76)
Timed-Off ControlLB-61378A(47J35)
UnitStand-Off Kit94J45 94J45 94J45 94J45 94J45 94J45 94J45
UnitHard-StartKit - 64J09 66K92 64J09 81J69 81J69 81J69
CompressorMonitor(Canadaonly)T6-1469 (45F08)
*Refrigerantcharge sufficient for20 ft. (6.0m) length ofrefrigerantlines.
©3/8in.x5/16 in.(9.5mm x7.9mm) reducerbushing (not furnished)isrequired forliquidline connection.

Page 3
I-GENERAL
Make sure all powerisdisconnected before
beginning electricalservice procedures.
DANGER
10ACCcondensingunitsareavailablein 1 -1/2,2,2-1/2,3,3
-1/2,4and5ton capacities.
All majorcomponents(indoorblowerand coil)mustbe
matched according to Lennoxrecommendationsforthe com-
pressortobecovered underwarranty.Refertothe Engineer-
ing Handbookforapproved system matchups.Amisapplied
systemwill cause erraticoperation and can resultin early
compressorfailure.
II -UNITCOMPONENTS
Unitcomponentsareillustrated infigure 1.
COMPRESSOR
CONTROL
BOX
SUCTIONLINE
SERVICE VALVE
SUCTIONLINE
OUTDOOR
FAN/MOTOR
10ACC UNITCOMPONENTS
FIGURE1
LIQUIDLINE
SERVICE VALVE
DISCHARGE
LINE
FIGURE2
DUALCAPACITOR
(C12)
START
CAPACITOR(C7)
(option only)
POTENTIAL
RELAY(K31)
(option only)
COMPRESSOR
CONTACTOR
(K1)
10ACC UNITCONTROLBOX
RECIPROCATINGCOMPRESSOR
GROUNDING
LUG
FIGURE3
DUALCAPACITOR
(C12)
COMPRESSOR
CONTACTOR
(K1)
10ACC UNITCONTROLBOX
Scroll Compressor
GROUNDING
LUG

Page 4
A-ControlBox(Figures 2 &3)
Electricalopeningsareprovidedunderthecontrolboxcov-
er.Fieldthermostatwiring ismade tocolor-coded pigtail
connections.
1-CompressorContactorK1
Thecompressorisenergizedbyacontactorlocatedinthe
controlbox.Seefigure2.Single-polecontactorsareused
in 10ACC units.K1isenergized bythe indoorthermostat
terminalY1(24V)when thermostatdemand ispresent.
10ACC unitsare notequipped with a 24Vtransformer.All
24 VACcontrolsare powered bythe indoorunit. Referto
wiring diagram.
DANGER
Shock Hazard
10ACC unitsuse single-pole con-
tactors.Oneleg ofcompressor,
capacitorand condenserfanare
connectedtoline voltage atall
times.Potentialexistsforelectri-
calshock resulting ininjuryor
death.Remove all poweratdis-
connectbefore servicing.
Cancause personal injuryordeath.
2-DualCapacitorC12
Thecompressorandfanin10ACCseriesunitsuseper-
manentsplitcapacitormotors.The capacitorislocated
insidetheunitcontrolbox(seefigures2and 3).Asingle
“dual”capacitor(C12)isusedforboththefanmotorand
the compressor (seeunitwiringdiagram).The fan side
andthecompressorsideof thecapacitorhavedifferent
MFDratings.For ratings see side ofcapacitor.
3-StartCapacitorC7(option)
Startcapacitor (C7)iswired in parallelwiththe compres-
sorside of the dualcapacitor.The capacitorislocated in-
side the unitcontrolbox(see figure 2).C7is switched off
bypotentialrelay(K31)when the compressornearsfull
speed.Thestartcapacitorisratedat330VACandhasan
MFDrating of176-216.
4-Potential(Start) Relay K31 (option)
PotentialrelayK31islocatedinsidetheunitcontrolbox
(see figure 2).The relayisnormally closed when con-
tactorK1isde-energized.WhenK1energizes,thecom-
pressorimmediatelybegins start-up.K31 remains closed
during compressorstart-up and the startcapacitorC7re-
mainsinthe circuit. When the compressor reaches75%ofits
speed,K31isenergized.WhenK31energizes,thecontacts
open and the startcapacitorC7istaken outof the circuit.

Page 5
B-Compressor
10ACC-042,-048 and -060 unitsare equipped with a
scroll compressor.Forcompressorspecifications see
“ELECTRICALDATA”sectioninthismanualorthecom-
pressornameplate.
SCROLL COMPRESSOR
DISCHARGE
SUCTION
FIGURE4
1-Scroll Compressor
The scroll compressordesign is simple,efficientand re-
quiresfewmoving parts.Acutawaydiagramof the scroll
compressoris showninfigure 4.The scrollsarelocated in
thetopofthecompressorcanandthemotorislocatedjust
below.The oil level isimmediatelybelowthe motor.
The scroll isasimplecompression conceptcentered
aroundtheuniquespiralshapeofthescrollanditsinherent
properties.Figure5showsthebasicscrollform.Twoiden-
ticalscrollsaremated togetherforming concentric spiral
shapes(figure6).Onescroll remains stationary,whilethe
otherisallowed to“orbit” (figure 7).Notethat the orbiting
scrolldoesnotrotate orturnbutmerely“orbits”thestation-
ary scroll.
SCROLL FORM
FIGURE5
FIGURE6
STATIONARY SCROLL
ORBITINGSCROLL
DISCHARGE
SUCTION
CROSS-SECTIONOFSCROLLS
TIPS SEALED BY
DISCHARGE PRESSURE
DISCHARGE
PRESSURE
The counterclockwise orbiting scroll drawsgasintothe out-
ercrescentshaped gaspocketcreated bythe twoscrolls
(figure 7 -1).The centrifugalaction of the orbiting scroll
sealsofftheflanksofthescrolls(figure7-2).Astheorbiting
motion continues, the gasisforced towardthe centerof the
scroll and the gaspocketbecomes compressed (figure7-
3).When the compressed gasreachesthe center,itisdis-
charged verticallyintoachamberand discharge portinthe
top of the compressor (figure 6).The discharge pressure
forcing down on the top scroll helps sealoff the upperand
loweredges(tips)of the scrolls(figure6).Duringasingle
orbit,severalpocketsofgasarecompressedsimultaneous-
lyproviding smoothcontinuous compression.
The scroll compressoristolerant tothe effectsofliquidre-
turn. Ifliquidentersthescrolls,theorbitingscrollisallowed
toseparatefromthe stationary scroll.The liquidisworked
towardthe centerof the scroll and isdischarged. If the
compressorisreplaced,conventionalLennox cleanup
practicesmustbe used.
Due toitsefficiency, the scroll compressoris capable of
drawingamuch deepervacuumthan reciprocating com-
pressors.Deep vacuumoperation can causeinternalfu-
site arcing resulting in damaged internalpartsand will re-
sultincompressorfailure.Neveruse a scroll compressor
forevacuatingor“pumping-down”thesystem.Thistypeof
damagecan bedetectedand willresultindenialofwarran-
ty claims.
NOTE-During operation, the head ofascroll compressor
maybe hotsinceitisinconstantcontactwith discharge
gas.

Page 6
SCROLL
HOWASCROLL WORKS
SUCTIONSUCTION
SUCTION
MOVEMENTOFORBIT
STATIONARY SCROLL
ORBITING
CRESCENT
SHAPEDGAS
POCKET
HIGH
PRESSURE
GAS DISCHARGE
POCKET
FLANKS
SEALEDBY
CENTRIFUGAL
FORCE
12
34
SUCTION
INTERMEDIATE
PRESSURE
GAS
SUCTION
POCKET
FIGURE7
C-CondenserFanMotor
Allunitsusesingle-phasePSCfanmotorswhichrequirea run
capacitor. In all units, the condenserfan is controlled bythe
compressorcontactor.
ELECTRICALDATAtablesinthismanualshowspecifi-
cationsforcondenserfansused in 10ACCs.
Accesstothe condenserfanmotoronallunitsisgained
byremoving the seven screws securing the fanassem-
bly.See figure 8.The condenserfan motorisremoved
fromthe fan guard byremoving the fournutsfound on
the top panel.See figure 9 ifcondenserfan motor re-
placementisnecessary.
FAN
CONDENSERFAN MOTOR
AND COMPRESSOR ACCESS
Remove (7)screws
REMOVE (7)SCREWS
SECURINGFAN GUARD.
REMOVE FAN GUARD/FAN
ASSEMBLY.
MOTOR
FAN GUARD
WIRING
FIGURE8
RACEWAY
Remove (4)nuts
ALIGNFAN HUBFLUSHWITHEND OFSHAFT
F
I
G
U
R
E
9

Page 7
III -REFRIGERANTSYSTEM
A-Plumbing
Fieldrefrigerantpiping consistsofliquid and suction lines
fromthecondensingunit(sweatconnections)totheindoor
evaporatorcoil (flare orsweatconnections).Use Lennox
L10 (flare)orL15 (sweat, non-flare)seriesline setsas
shownintable 1 orusefield-fabricated refrigerantlines.
Separate discharge and suction service portsare pro-
videdoutside theunit forconnectionofgauge manifold
during charging procedure.
TABLE1
ModelLiquid
Line
Suction
Line
L15
LineSets
10ACC-018
10ACC-024 5/16 in* (8mm)5/8in (16 mm)
L15-21
20 ft.-50 ft.
(6m-15m)
10ACC-030
10ACC-036 3/8in (10 mm)3/4in. (19 mm)
L15-41
20 ft.-50 ft.
(6m-15m)
10ACC-042
10ACC-048 3/8in (10 mm)7/8in. (22 mm)
L15-65
30 ft.-50 ft.
(9m-15m)
10ACC-060 3/8in
(10 mm)1-1/8in. (29 mm)Field Fabricated
*Fieldfabricate.See Corp.9351-L9 RefrigerantPiping Nabual
B-Service Valves
The liquid and suction line servicevalves(figures10 and 11)
and gauge portsare accessiblefromoutside the unit.
The valveisequipped with a service port. The service ports
are used forleaktesting,evacuating,charging and checking
charge.Aschradervalveisfactoryinstalled.Aserviceportcap
is supplied to protect the schradervalvefromcontamination
and serve asthe primaryleak seal.
NOTE-Always keep valvestemcaps clean.
To Access SchraderPort:
1-Removeservice portcap with an adjustablewrench.
2-Connectgauge tothe service port.
3-When testing is completed,replaceservice portcap.
Tighten fingertight, then an additional1/6turn.
To Open Liquid orSuction LineService Valve:
1-Removestemcap with an adjustablewrench.
2-Using servicewrench and hexhead extension (3/16 for
liquidline and 5/16 forsuction line)back the stemout
counterclockwise until the valvestemjust touchesthe
retaining ring.
3-Replacestemcap tightenfirmly.Tightenfingertight,then
tighten an additional1/6turn.
Do notattempt to backseat this valve.Attemptsto
backseat this valve will cause snapring toexplode
fromvalve bodyunderpressureofrefrigerant.
Personal injury and unitdamagewill result.
DANGER
To Close Liquid orSuction LineService Valve:
1-Removestemcap with an adjustablewrench.
2-Using servicewrench and hexhead extension (3/16 for
liquidline and 5/16 forsuction line), turnstemclockwise
toseat the valve.Tighten firmly.
3-Replacestemcap.Tighten fingertight, then tighten an
additional1/6turn.
FIGURE10
LIQUIDLINE SERVICE VALVE (VALVE OPEN)
SCHRADER
VALVE
SER-
VICE
PORT
SERVICE
PORT
CAP
INSERTHEX
WRENCH HERE
INLET(TO
INDOOR COIL)
OUTLET(TO
COMPRESSOR)
STEMCAP
SCHRADERVALVE OPEN
TOLINE SETWHENVALVE
ISCLOSED(FRONT
SEATED)
SERVICE
PORT
SERVICE
PORTCAP
RETAININGRINGSTEMCAP
OUTLET(TO
COMPRESSOR)
INSERTHEX
WRENCH HERE
LIQUIDLINE SERVICE VALVE (VALVE CLOSED)
(VALVE FRONT
SEATED)
INLET
(TOINDOOR COIL)

Page 8
FIGURE11
SUCTIONLINE SERVICE VALVE (VALVE OPEN)
SCHRADER
VALVE
SERVICE PORT
SERVICE PORT
CAP
INSERTHEX
WRENCH HERE
INLET(TO
INDOOR COIL)
OUTLET(TO
COMPRESSOR)
STEMCAP
SCHRADERVALVE OPEN
TOLINE SETWHENVALVE IS
CLOSED(FRONTSEATED)
SERVICE
PORT
SERVICE PORT
CAP
RETAININGRINGSTEMCAP
INSERTHEX
WRENCH HERE
SUCTIONLINE SERVICE VALVE (VALVE CLOSED)
(VALVE FRONT
SEATED)
INLET(TO
INDOOR COIL)
OUTLET(TO
COMPRESSOR)
Suction Line(Ball Type)Service Valve(5Ton Only)
Aball-type full servicevalveisused on 10ACC 5ton
units.Thesesuction line servicevalvesfunction the
sameway,differencesareinconstruction.Valvesare
notrebuildable.Ifavalve hasfailed itmustbe replaced.Aball
valveisillustrated infigure 12.
The ball valveisequipped with a service port. Aschrader
valveisfactoryinstalled.Aservice portcap is supplied to pro-
tect the schradervalvefromcontamination and assure a
leakfree seal.
SUCTIONLINE(BALL TYPE)SERVICE VALVE
(VALVE OPEN)
FIGURE12
SCHRADER CORE
SERVICE PORT
SERVICE
PORT
CAP
STEMCAP
INLET
(FROMINDOOR COIL)
OUTLET
(TO
COMPRESSOR)
STEM
USE ADJUSTABLEWRENCH
ROTATE STEMCLOCKWISE 90_TOCLOSE
ROTATE STEMCOUNTER-CLOCKWISE 90_TO OPEN
BALL
(SHOWNOPEN)
IV-CHARGING
A-Pumping DownSystem
CAUTION
Deepvacuumoperation (operating compressorat0
psig orlower)cancause internalfusite arcing
resulting inadamaged orfailedcompressor.This
typeofdamagewill resultin denialofwarranty claim.
Thesystem maybepumpeddownwhen leak checkingthe
line setand indoorcoil ormaking repairstothe line setor
indoorcoil.
1-Attach gauge manifold.
2-Frontseat(close)liquidline valve.
3-Startoutdoorunit.
4-Monitorsuction gauge.Stop unitwhen 0 psigisreached.
5-Frontseat(close)suction line valve.
B-Leak Testing (To BeDone
BeforeEvacuating)
1-Attachgaugemanifoldandconnectadrumofdrynitro-
gen tocenterportofgauge manifold.
2-Open high pressurevalve on gauge manifold and
pressurizelinesetandindoorcoilto150psig(1034
kPa).
3-Check linesand connectionsforleaks.
NOTE-If electronicleakorHalide detectorisused,add a
small amountofR-22 (3to5psig[20kPato 34kPa])then
pressurizewith nitrogen to 150 psig.
4-Release nitrogen pressurefromthe system,correctany
leaks and recheck.

Page 9
CAUTION
When using drynitrogen,apressurereducing reg-
ulatormustbeusedto preventexcessive pres-
surein gaugemanifold,connecting hoses,and
withinthe system.Regulatorsetting mustnotex-
ceed150 psig(1034 kpa).Failureto use a regulator
cancause equipment failureresulting ininjury.
C-Evacuating theSystem
1-Attachgaugemanifold.Connectvacuumpump(withvac-
uumgauge)tocenterportofgauge manifold.With both
manifoldservicevalvesopen,startpump and evacuate
indoorcoil and refrigerantlines.
IMPORTANT
Atemperature vacuumgauge,mercury vacuum
(U-tube),orthermocouplegauge should beused.
TheusualBourdon tubegauges arenotaccurate
enough inthe vacuumrange.
IMPORTANT
The compressorshould neverbeusedtoevacu-
atearefrigeration orairconditioning system.
2-Evacuatethe systemto 29 inches(737mm)vacuum.
During the early stagesofevacuation,itisdesirableto
stopthevacuumpumpatleastoncetodetermineifthere
isarapidloss ofvacuum.Arapidloss ofvacuumwould
indicatealeakinthe systemand a repeatof the leak
testing section would be necessary.
3-Aftersystemhasbeen evacuated to 29 inches
(737mm),close gauge manifoldvalvestocenterport,
stop vacuumpump and disconnect fromgauge man-
ifold.Attach an uprightnitrogen drumtocenterportof
gaugemanifold andopendrumvalveslightlytopurge
line atmanifold.Break vacuuminsystemwith nitro-
gen pressure byopening manifold high pressure
valve.Closemanifold high pressurevalvetocenter
port.
4-Close nitrogen drumvalve and disconnect from
gaugemanifoldcenterport.Releasenitrogenpres-
surefromsystem.
5-Connectvacuumpumpto gauge manifoldcenter
port. Evacuatesystemthrough manifoldservice
valvesuntil vacuuminsystemdoesnotrise above
.5mm ofmercuryabsolute pressure or500 microns
within a 20-minute period afterstopping vacuumpump.
6-Afterevacuation is complete,closemanifoldcenterport,
and connectrefrigerantdrum.Pressurizesystem
slightlywithrefrigerant to break vacuum.
D-Charging
Unitsarefactory charged withthe amountofHCFC-22 re-
frigerantindicated on the unitnameplate.This charge is
basedonamatching indoorcoil and outdoorcoil with a 20
ft. (6.1m)line set. Forvarying lengthsofline set, referto
table 2 for refrigerantcharge adjustment. Ablank spaceis
provided on the nameplatetolist the actualfieldcharge.
TABLE2
Liquid Line
SetDiameter
Oz.per5ft.(g per1.5m)adjust
from20 ft.(6.1m)line set*
5/16 in.(8mm)2 ounce per5ft. (57g per1.5m)
3/8in.(10 mm)3 ounce per5ft. (85g per1.5m)
*If line lengthisgreaterthan 20 ft. (6.1m),add thisamount.
If line lengthisless than 20 ft. (6.1m),subtract thisamount.
The condensing unitshouldbecharged during warm
weather.However,applicationsariseinwhichcharging
mustoccurinthecoldermonths.The method ofcharging is
determined bythe unit’srefrigerantmetering device and
the outdoorambient temperature.
Measurethe liquidline temperature and the outdoorambi-
ent temperature asoutlined below:
1.-Connect the manifold gauge set tothe servicevalves:
lowpressure gauge tosuction valveservice port; high
pressure gauge toliquidvalveservice port. Connect
the centermanifold hoseto an uprightcylinderof
HCFC-22.Closemanifold gauge setvalves.
2.-Settheroomthermostattocallforheat.Thiswillcreate
thenecessaryloadforproperlychargingthe systemin
the cooling cycle.
3.-Useadigitalthermometertorecordthe outdoorambi-
ent temperature.
4.-When the heating demand hasbeen satisfied,switch
thethermostat tocoolingmodewithasetpointof68_F
(20_C).When pressureshavestabilized,use a digital
thermometertorecordthe liquidline temperature.
5.-The outdoortemperaturewill determine whichcharg-
ing method to use.Proceed withthe appropriate
charging procedure.

Page 10
Weighing intheChargeFixedOrifice or
TXV Systems–OutdoorTemp<60_F(16_C)
Ifthe systemis voidofrefrigerant,orif the outdoorambient
temperatureis cool, the refrigerantcharge should be
weighed intothe unitaccording tothe totalamountshown
on the unitnameplate.Thismaybe done afteranyleaks
have been repaired.Ifweighing facilitiesare notavailable
orifunitisbeing charged during warmweather, followone
of the otherproceduresoutlined below.
1-Recoverthe refrigerant fromthe unit.
2-Conductaleak check, then evacuate aspreviously
outlined.
3-Weigh inthe factory charge according tothe amount
recorded on the outdoorunitnameplate.
Charging Using theSubcooling Method
FixedOrifice Systems–OutdoorTemp.
>65_F(18_C)
Ifyouchargeafixedorificesystemwhentheoutdoorambi-
entis65_F(18_C)orabove,usethesubcooling method to
charge the unit.
1-Withthe manifold gauge hosestill onthe liquidservice
portand the unitoperating stably,use a digitalther-
mometertorecordthe liquidline temperature.
2-Atthesametime,recordthe liquidlinepressurereading.
3-Useatemperature/pressurechart forHCFC-22 to de-
termine the saturation temperatureforthe liquidline
pressurereading.
4-Subtracttheliquidlinetemperaturefromthesaturation
temperature(accordingtothe chart)todeterminesub-
cooling.(Saturation temperature-Liquidlinetem-
perature=Subcooling)
5-Comparethe subcooling value withthoseintable 3. If
subcooling isgreaterthan shown,somerefrigerant
mustbe recovered. If subcooling isless than shown,
somerefrigerantmustbe added.
Table 3
10ACC Subcooling Values
(FixedOrifice SystemsOnly)
OUTDOOR
T
E
M
P
.
LIQUIDSUBCOOLING[+1_F(.6_C)]
T
E
M
P
.
_F(_C)18 24 30 36 42 48 60
65
(18)13 (7)14 (8)14 (8)17 (9.5)17 (9.5)15 (8.3)14 (8)
70
(21)13 (7)14 (8)14 (8)17 (9.5)17 (9.5)14 (8)15 (8.3)
75
(24)13 (7)13 (7)13 (7)16 (9)16 (9)13 (7)15 (8.3)
80
(27)12 (6.7)13 (7)13 (7)15 (8.3)15 (8.3)13 (7)14 (8)
85
(29)12 (6.7)12 (6.7)13 (7.8)14 (8)14 (8)12 (6.7)14 (8)
90
(32)11 (6)12 (6.7)12 (6.7)14 (8)14 (8)12 (6.7)13 (7)
95
(35)10 (5.6)11 (6)11 (6)12 (6.7)14 (8)12 (6.7)13 (7)
100
(38)9 (5)9 (5)10 (5.6)11 (6)13 (7)11 (6)12 (6.7)
105
(41)8 (4.5)8 (4.5)9 (5)10 (5.6)12 (6.7)10 (5.6)12 (6.7)
110
(43)7 (4)7 (4)7 (4)9 (5)11 (6)9 (5)11 (6)
115
(45)7 (4)6 (3.3)6 (3.3)8 (4.5)11 (6)8 (4.5)10 (5.6)
Charging Using theApproachMethod
TXV Systems-- OutdoorTemp.>60_F(16_C)
When an expansion valvesystemisbeing charged when
theoutdoorambienttemperatureis60_F(16_C)orabove,
itisbest tocharge the unitusing the approachmethod.
Subtract the outdoorambient temperaturefromthe liquid
line temperatureto determine the Approachtemperature.
(Liquid Line_F(_C)-OutdoorAmbient_F(_C)=Ap-
proach Temperature.)The resulting difference(Ap-
proachtemperature)should agree withthe valuesgivenin
table 4.Ifnot, add refrigerant tolowerthe approachtem-
peratureor recoverrefrigerantfromthesystemtoincrease
the approachtemperature.
Table 4
ApproachMethod
ModelNo.Approach Temperature
Liquid Line-OutdoorAmbient_F(_C)
10ACC-018 7 (4)
10ACC-024 9 (5)
10ACC-030 12 (6.7)
10ACC-036 11 (6)
10ACC-042 13 (7)
10ACC-048 8 (4.5)
10ACC-060 13 (7)
NOTE-Forbestresults,usethe same digitalthermometertocheck both
outdoorambientand liquidtemperatures.

Page 11
Table 5
NormalOperating Pressures In psig(liquidand suction +/-2psig)*
Unit/
M
e
t
e
r
i
n
g
Out.Coil
E
n
t
e
r
i
n
g
-018 -024 -030 -036 -042 -048 -060
M
e
t
e
r
i
n
g
Device
E
n
t
e
r
i
n
g
AirTemp.
°°
F(
°°
C)LIQ. SUC.LIQ. SUC.LIQ. SUC.LIQ. SUC.LIQ. SUC.LIQ. SUC.LIQ. SUC.
65 (18.3)154 62 165 68 170 76 168 67 178 67 163 68 189 72
75 (23.9)181 68 190 73 199 78 195 71 202 70 190 71 203 74
1
0
A
C
C
/
85 (29.4)210 73 219 77 231 80 224 75 235 71 220 74 233 77
10ACC /
f
i
x
e
d
o
r
i
f
i
c
e
95 (35.0)237 77 250 80 264 81 255 78 270 74 251 77 265 79
f
i
x
e
d
o
r
i
f
i
c
e
105 (40.6)272 82 282 83 300 82 289 82 308 78 288 79 301 82
110 (43)288 83 301 84 321 83 305 83 326 79 307 80 319 83
115 (45)306 85 317 85 339 84 324 84 347 80 325 82 339 84
65 (18.3)156 68 162 73 170 76 162 70 173 73 159 71 170 74
75 (23.9)180 70 189 74 199 78 187 74 201 74 188 72 201 76
1
0
A
C
C
/
85 (29.4)208 72 218 75 231 80 219 75 234 74 220 73 234 77
10ACC /
T
X
V
95 (35.0)237 73 249 77 264 81 253 77 269 75 251 76 270 79
T
X
V
105 (40.6)268 75 285 78 300 82 291 79 307 76 290 77 309 79
110 (43)284 76 301 79 321 83 310 80 326 77 309 78 331 80
115 (45)302 77 321 81 339 84 329 81 346 78 328 79 351 81
*These aretypicalpressures only. Indoorevaporatormatch up, indoorairquality,and evaporatorloadwill cause thepressures tovary.
IMPORTANT
Use table 5 to perform maintenance checks.Table 5
isnotaprocedureforcharging the system.Minor
variationsinthese pressures may bedueto differ-
ences ininstallations.Significantdeviations could
meanthat the systemisnotproperly charged orthat
aproblemexistswithsome componentinthe sys-
tem.See table 5.
E- Maintenance
WARNING
Electric shock hazard.Cancause inju-
ryordeath.Before attempting to per-
formany service ormaintenance,turn
the electricalpowerto unitOFF atdis-
connectswitch(es).Unitmay have
multiplepowersupplies.
Maintenanceand servicemustbeperformedbyaqualified
installerorservice agency.At the beginning ofeachcool-
ing season, the systemshouldbechecked asfollows:
1-Clean and inspect the condensercoil.Thecoil maybe
flushed with a waterhose.Makesure powerisoff be-
forecleaning.
2-Visuallyinspectconnecting linesand coilsforevi-
dence ofoil leaks.
3-Check wiring forlooseconnections.
4-Check forcorrectvoltage atunit(unitoperating).
5-Checkthe compressorand condenserfan motoramp-
draw.
NOTE-If the ownercomplainsofinsufficientcooling,
the unitshould be gauged and the refrigerantcharge
shouldbechecked.Refertothe charging section in
thisinstruction.
EvaporatorCoil
1-Clean coil,ifnecessary.
2-Check connecting linesand coilsforevidence ofoil
leaks.
3-Check the condensate pan line and clean itifneces-
sary.
IndoorUnit
1-Clean orchange filters.
2-Adjustblowerspeed forcooling.Thepressure drop over
the coil should be measured to determine the correct
blowerCFM.Refertothe unitinformation servicemanu-
alforpressure drop tablesand procedure.
3-BeltDriveBlowers-Check belt forwearand proper
tension.
4-Check all wiring forlooseconnections
5-Check forcorrectvoltage atunit(bloweroperating).
6-Check amp-drawon blowermotor.

Page 12
V-WIRINGDIAGRAMSAND SEQUENCEOFOPERATION
10ACC OPERATINGSEQUENCE
7
1
2
4
6
3
5
NOTE-The thermostatused maybe electromechanicalorelectronic.
NOTE-Transformerinindoorunitsuppliespower (24 VAC)tothe thermostatand outdoorunitcontrols.
COOLING:
1-Cooling demand initiatesatY1inthe thermostat.
2-24VACenergizes compressorcontactorK1.
3-K1-1N.O.closes,energizing compressor (B1)and outdoorfan motor (B4).
4-Compressor (B1)and outdoorfan motor (B4)beginimmediate operation.
END OFCOOLINGDEMAND:
5-Cooling demand is satisfied.TerminalY1isde-energized.
6-CompressorcontactorK1isde-energized.
7-K1-1 opensand compressor (B1)and outdoorfan motor (B4)are de-energized and stop immediately.