Duke RUF 48 User manual

Service Manual
This manual is Copyright © 2005 Duke Manufacturing Company. All rights reserved.
Reproduction without written permission is prohibited. Duke is a registered
trademark of the Duke Manufacturing Company.
Duke Manufacturing Company
2305 N. Broadway
St. Louis, MO 63102
Phone: [phone]
Toll Free: 1-800-735-3853
Fax: [phone]
www.dukemfg.com
P/N 219205A
Please read this manual completely before attempting to
install, operate or service this equipment
REFRIGERATED BACK BAR
MODEL
RUF 48

Service Manual for Refrigerated Back Bar Model RUF 48
2
IMPORTANT WARNING AND SAFETY INFORMATION
WARNING
READ THIS MANUAL THOROUGHLY BEFORE OPERATING, INSTALLING, OR PERFORM-
ING MAINTENANCE ON THE EQUIPMENT.
WARNING
FAILURE TO FOLLOW INSTRUCTIONS IN THIS MANUAL CAN CAUSE PROPERTY
DAMAGE, INJURY OR DEATH.
WARNING
DO NOT STORE OR USE GASOLINE OR OTHER FLAMMABLE VAPORS OR LIQUIDS
IN THE VICINITY OF THIS OR ANY OTHER APPLIANCE.
WARNING
UNLESS ALL COVER AND ACCESS PANELS ARE IN PLACE AND PROPERLY SE-
CURED, DO NOT OPERATE THIS EQUIPMENT.
CAUTION
Observe the following:
• Minimumclearancesmustbemaintainedfromallwallsandcombustiblematerials.
• Keeptheequipmentareafreeandclearofcombustiblematerial.
• Adequateclearanceforairopenings.
• Operateequipmentonlyonthetypeofelectricityindicatedonthespecicationplate.
• Retainthismanualforfuturereference.

3
Service Manual for Refrigerated Back Bar Model RUF 48
CONTENTS
SPECIFICATIONS...............................................................................................................................4
INSTALLATION...................................................................................................................................4
Location.......................................................................................................................................4
Inside Unit....................................................................................................................................4
Outside Unit.................................................................................................................................4
Leveling.......................................................................................................................................4
Stabilizing....................................................................................................................................4
Electrical Connection...................................................................................................................4
MAINTENANCE..................................................................................................................................5
Stainless Steel Care and Cleaning..............................................................................................5
PREVENTIVE MAINTENANCE...........................................................................................................6
Cleaning the Condenser Coil.......................................................................................................6
Door Gasket Maintenance...........................................................................................................6
Drain Maintenance – Base..........................................................................................................7
PARTS REPLACEMENT.....................................................................................................................7
 ThermostatReplacement............................................................................................................7
 EvaporatorFanReplacement......................................................................................................8
 RefrigerationSystemReplacement.............................................................................................8
 DoorReplacementandAdjustment.............................................................................................9
 DoorGasketReplacement..........................................................................................................9
 RechargingRefrigerationSystem................................................................................................9
Tools............................................................................................................................................9
Charging Procedure....................................................................................................................9
TROUBLESHOOTING......................................................................................................................11

Service Manual for Refrigerated Back Bar Model RUF 48
4
SPECIFICATIONS
MODEL DESCRIPTION VOLTAGE AMPS PH.
RUF48 48”Refrigerated 120VAC(60Hz) 6.4 1
 BackBar 220VAC(50Hz) 3.2 1
MODEL DESCRIPTION HEIGHT WIDTH LENGTH
RUF48 48”Refrigerated 36.00In. 29.50In. 48.00In.
Back Bar
INSTALLATION
Location
Theunitrepresentedinthismanualisintended
forindooruseonly.Besurethechosenlocation
hasaoororcounterstrongenoughtosupport
the total weight of the unit. Reinforce the oor
orcounterifnecessarytoprovideformaximum
loading.Forthemostefcientoperation,besure
toprovidegoodaircirculationinsideandout.
The outline dimensional drawing for the unit is
shownbelowinFigures1.
Figure 1
48” Refrigerated Back Bar (RUF 48)
Inside Unit
Provideadequatespacealongthefront,backand
sidestakingcaretonotblockairowtothefans.
Outside Unit
Be sure that the unit has access to ample air;
avoid hot corners and locations near stoves and
ovens.
Leveling
Be sure that the unit is placed on a rm, at
surface/oor.Checkforcracksinooringortile
andavoidtheseareasifpossible.Ifnecessary
placesupportpads,properlyratedfortheweight
oftheunit,to“bridge”unevenorcrackedooring.
Levelunitaccordingly.
Stabilizing
Usethelegadjustmentstoinsurethattheunitis
solidtotheoorsurfaceatallfourcontactpoints.
Insurethattheunitdoesnot“rock”whenpressure
isappliedtothetopcorners.
Electrical Connection
TheRUF48isavailableasa120VAC,60Hzor
as a 220VAC, 50 Hz dependent on model.All
electricalconnectionsshouldbeperformedbya
certiedelectricianandshouldcomplywithlocal
electricalcodesforyourmunicipality.
WARNING
REFER TO THE AMPERAGE DATA
LIST IN THE SPECIFICATIONS OR
THE SERIAL TAG DATA AND YOUR
LOCAL CODE OR THE NATIONAL
ELECTRICAL CODE TO BE SURE UNIT
IS CONNECTED TO THE PROPER
POWER SOURCE. A PROTECTED
CIRCUIT OF THE CORRECT VOLTAGE
AND AMPERAGE MUST BE RUN FOR
CONNECTION OF THE SUPPLY CORD
OR PERMANENT CONNECTION TO THE
UNIT. THE POWER MUST BE TURNED
OFF AND DISCONNECTED WHENEVER
PERFORMING MAINTENANCE OR RE-
PAIR FUNCTIONS.

5
Service Manual for Refrigerated Back Bar Model RUF 48
MAINTENANCE
Stainless Steel Care and Cleaning
Stainlesssteelcontains70-80%iron,whichwill
rust. It also contains 12-30% chromium, which
forms an invisible passive lm over the steel
surfaceandactsasashieldagainstcorrosion.
As long as the protective lm remains intact,
the metal will not corrode. However, if the lm
is broken or contaminated, outside elements
can begin to breakdown the steel and begin to
form rust or discoloration. To prevent rust and
discolorationonstainlesssteel,severalimportant
stepsneedtobetaken.
CAUTION: Never use steel wool pads or
wire brushes or scrapers. Avoid
cleaning solutions that contain
alkaline or chloride.
Use alkaline based or non-chloride cleaning
solutions. Anything containing chloride will
damage the protective lm on stainless steel.
Chlorides are found in household and industrial
cleaners and also in hard water and salts. If a
chlorideoralkalinecleanerhasbeenused,rinse
repeatedlyanddrythoroughly.
Always use only soft cloths or plastic scouring
pads.Forroutinecleaning,usewarmsoapywater.
Forstubbornstainsuseanon-abrasivecleanser.
For heavy grease use a degreaser. For best
results,rubwiththegrainofthesteel.
Pittingandcrackingareearlysignsofstainless
steelbreakdown.Specialstainlesssteelcleaners
can restore and preserve the protective lm. If
signsofbreakdownappear,thoroughlycleanand
dryallsurfaces.Beginregularapplicationofa
highqualitystainlesssteelcleaneraccordingto
themanufacturer’sinstructions.Again,alwaysrub
withthegrainofthesteelforbestresults.
CAUTION: Never use an acid-based cleanser!
Be sure to clean all food products
from any stainless surface. Many
food products contain acid, which
can deteriorate the nish. Common
foods include tomatoes, peppers
and other vegetables.
WARNING
THE POWER MUST BE TURNED OFF
AND DISCONNECTED AT ALL TIMES
DURING MAINTENANCE OR REPAIR
FUNCTIONS.

Service Manual for Refrigerated Back Bar Model RUF 48
6
PREVENTIVE MAINTENANCE
Cleaning the Condenser Coil
Failure to maintain a clean condenser coil can
initiallycausehightemperaturesandexcessive
run times. Continuous operation with dirty or
cloggedcondensercoilscanresultincompres-
sor failure. Neglecting the condenser coil
cleaningprocedureswillvoidallwarrantiesand
repairorreplacementcostsassociatedwiththe
compressor.
CAUTION: To clean the condenser, never use
a high-pressure water wash, which
candamageelectricalcomponents
located at or near the condenser
coil.
Figure 2
Location of Condensing Coil
and Air Filter
The condenser coil is located and accessed at
therearoftheunit(seeFigure2).Thecondenser
coilrequiresregularcleaningandshouldbedone
every 60 days. However, if large amounts of
dust and grease accumulate sooner, clean the
condensercoilevery30days.
For light dust, use a soft, non-wire brush.
For heavier dust, use a vacuum or blow with
compressedair.
Forheavygrease,useadegreasingagentmade
specically for condenser coils on refrigeration
units. Spray the degreasing agent on the coil
andthenblowwithcompressedair.Neverwash
with high-pressure water, which can damage
theelectricalcomponentslocatedatornearthe
condensercoil.
Door Gasket Maintenance
Doorgasketsrequireregularcleaningtoprevent
mold and mildew build up and to maintain
elasticity for proper seal function. Warm soapy
waterisadequateforcleaningthegasket.Avoid
usingfullstrengthcleaningproducts,whichcan
causethegaskettobecomebrittleandresultin
impropersealfunction.Neverscrapeorcleanthe
gasketwithsharptoolsorknives.

7
Service Manual for Refrigerated Back Bar Model RUF 48
Drain Maintenance – Base
Locatedattherearofeachunitisadrainhose,
which removes the condensation from the
evaporatorcoilanddeposits itintoadrainpan
forevaporation(seeFigure3).
Figure 3
Location of Drain Hose and Drain Pan
If excessive water accumulates inside the unit,
check to see that the drain hose is connected
fromtheevaporatorhousingtothedrainpan.If
water accumulates underneath the unit, check
to see that the drain hose is located above the
drainpan.
Alevelunitisessentialforproperdrainage.Be
sure to provide a level surface below the unit,
especiallyiftheoorisnotlevel.Keepthedrain
panfreefromdirt,dustanddebristopreventwater
frombackingupandoverowingfromthedrain
panontotheoor.
PARTS REPLACEMENT
Thermostat Replacement
General
The thermostat is located inside the cooling
compartment and is accessible through the
doors.
1. Disconnectunitfrompowersource.
2. Removeshelves.
3. Removeshelfsupport.
4. Removesheetmetalpanel.
5. Removethermostatfrombackpanel.
6. Remove thermostat probe from evaporator
coil.
7. Taganddisconnectthermostatwiring.
8. Removethermostatfromunit.
9. Installreplacementthermostat.
NOTE:Donotkinkthermostatprobe.
NOTE:Toensureproperoperation,place8”of
thermostatprobeintoevaporatorcoil.
10.Installthermostatprobeinevaporatorcoil.
11.Usingtags,connectthermostatwiring.
12.Installsheetmetalpanel.
13.Installshelfsupport.
14.Installshelves.
15.Connectunittopowersourceandtest.

Service Manual for Refrigerated Back Bar Model RUF 48
8
Evaporator Fan Replacement
General
Theevaporatorfanislocatedandaccessedinside
thecoolingcompartmentandisremovedasan
assemblyfromthebackpanel.
1. Disconnectunitfrompowersource.
2. Removeshelves.
3. Removeshelfsupport.
4. Removesheetmetalpanel.
5. Taganddisconnectevaporatorfanwiring.
6. Removeevaporatorfanmountinghardware.
7. Removeevaporatorfan.
8. Installreplacementevaporatorfan.
9. Installevaporatorfanmountinghardware.
10.Usingtags,connectevaporatorfanwiring.
11.Installsheetmetalpanel.
12.Installshelfsupport.
13.Installshelves.
14.Connectunittopowersourceandtest.
Refrigeration System Replacement
General
Therefrigerationsystemassemblyislocatedin
therearoftheunit.
1. Disconnectunitfrompowersource.
2. Usingarefrigeration-chargingunit,evacuate
refrigerantfromthesystemaccordingtoDuke
ManufacturingServiceBulletinNumber26.
3. Remove expansion valve from refrigeration
assembly.
4. Removeevaporatortubingfromrefrigeration
assembly.
5. Remove refrigeration assembly mounting
hardware.
6. Taganddisconnectwiringatjunctionbox.
7. Removewiringharnessclamps.
8. Remove mounting nut from condenser coil
tubingindrainpan.
9. Installreplacementrefrigerationassemblyonto
framemounts.
10.Installmountingnuttocondensercoil.
11.Installwiringharnessclamps.
12.Usingtags,connectwiringatjunctionbox.
13.Install refrigeration assembly mounting
hardware.
14.Install evaporator tubing to refrigeration
assembly.
15.Install expansion valve to refrigeration
assembly.
16.ChargesystemaccordingtoDukeManufacturing
ServiceBulletinNumber26.
17.Connectunittopowersourceandtestunit.

9
Service Manual for Refrigerated Back Bar Model RUF 48
Door Replacement and Adjustment
General
Doorsmaybecomemisalignedduringshipment
butareeasilyadjusted.
1. Foralowhangingdoor,usea3/8”openwrench
totighten,butdonotovertighten,bothtopand
bottomhingescrews.
2. Placeaatscrewdriveragainstoutersideof
bottomhingeandlightlytapwithahammer
untildoorisproperlyaligned.
3. If necessary, place at screwdriver against
inner side of top hinge and tap lightly with
hammeruntildoorisproperlyaligned.
4. Afterproperlyaligningdoors,tightenallhinge
screwssecurely.
Door Gasket Replacement
General
Thedoorgaskethasaretainingpanel.
1. Remove gasket door panel and mounting
screws.
2. Removegasketanddoorpanel.
3. Positionnewgasketandpanelondoor.
4. Securewithmountingscrews.Tightenscrews
evenlyarounddoorpanel.
Recharging Refrigeration System
General
To analyze the performance of a refrigeration
system,temperaturereadingsarerecordedand
convertedtopressurereadingsusingastandard
pressure/temperaturechart.
Whenitisnecessarytoserviceafactory-sealed
refrigerationsystemandreturnittoitsproperly
sealedcondition,strictlyadheretothefollowing
approvedprocedure.
Tools
• Standardhandandrefrigerationtools
• RefrigerantType:R-134A,Refertodatatag
foramount
Charging Procedure
NOTE:Priortorefrigerationsystemservice,special
caremustbetakenduringtheevacuationprocessto
removeair,moistureandothernon-condensables
fromthesystem.DukeManufacturingrecommends
thefollowingtripleevacuationmethod.Failureto
followthisproceduremayresultinpoorrefrigeration
systemperformance.
1. Evacuatesystemto1500microns.
2. Breakvacuumto2psigwithdrynitrogen.If
drynitrogenisunavailable,usesametypeof
refrigerantasusedinsystem.
3. Evacuatesystemto500microns.
Thesystemisnowreadytoreceiverefrigerant
chargeaccordingtoinformationondataplate.
CAUTION: Never use oxygen or acetylene in
place of dry nitrogen or refrigerant
forleaktesting.Aviolentexplosion
mayresult,causingpropertydamage,
personalinjuryordeath.Whenusing
nitrogentopressuretest,alwaysuse
apressureregulator.Failuretodoso
willresultinextremelyhighpressure
ofthecompressororothersystem
components and result in property
damage,personalinjuryanddeath.
NOTE: Prior to repair, ensure there is enough
process hose (approximately 12”) present to
completetherepairusingtheaboveprocedure.
Ifnot,installa newprocesshosebeforerepair
sequence.

Service Manual for Refrigerated Back Bar Model RUF 48
10
1. Installatemporaryaccessvalveonthehigh
and low side of process hoses as close to
factorycrimpsaspossible.
2. Usetemporaryvalvestoperformrepair.Duke
Manufacturingwillnotreimbursethecostof
permanentlyinstalledvalves.
3. Aftercompletingrepair,evacuatesystemusing
thetripleevacuationmethoddescribedinDuke
ManufacturingServiceBulletinNumber26.
4. Aftercompletingproperevacuationmethod,
recharge system, using proper refrigerant
accordingtoinformationondataplate.
5. Continue crimping process hose just below
temporaryvalveandagain2”belowcrimp.
6. Withcrimptoolinplace,remove temporary
valve.
7. Brazeshutendofprocesshose.
8. Allowtocoolforabout5minutes.
9. Removecrimptool.
10.Checkbrazedendforleaks.

11
Service Manual for Refrigerated Back Bar Model RUF 48
TROUBLESHOOTING
CAUSE
Unitnotpluggedin
Thermostatsettoowarm
Thermostatswitchstuck
openincoldestposition
Doors not sealing
Tornordamageddoor
gaskets
Evaporatorfannotrunning
Condenserfanmotornot
running
Dirtycondensercoilorlter
Refrigerant leak
Thermostatsettoocold
Thermostatswitchisstuck
intheclosedposition
Drainhoseplugged
Drain hose loose or
disconnectedfromdrain
pan
REMEDY
Plug unit in
Setthermostattoahighernumberfor
acoldertemperature
Replacethermostat
Adjustdoors
Replacegaskets
Checkandrepairorreplacemotor
Checkandrepairorreplacemotor
Cleancoilorlter
Findleak,repairandrecharge
Setthermostattoalowernumberfora
warmertemperature
Replacethermostat
Clear drain hose
Tighten or connect drain hose
SYMPTOM
Cabinettoowarm
Cabinet too cold
Waterinbottomofunit

Duke Manufacturing Company
2305 N. Broadway
St. Louis, MO 63102
Phone: [phone]
Toll Free: 1-800-735-3853
Fax: [phone]
www.dukemfg.com
P/N 219205A