Dometic B3351.531 Manual

1
INSTALLATION AND OPERATING INSTRUCTIONS
INSTALLATION & OPERATING
INSTRUCTIONS TYPE
B3351.531
B3300Series
Roof Top Air Conditioner
Used With
Mechanical Air Distribution Box Kit
3309278.004
This manual must be read and un-
derstood before installation, ad-
justment, service, or maintenance
is performed. This unit must be in-
stalled by a qualified service tech-
nician.Modificationofthisproduct
can be extremely hazardous and
could result in personal injury or
property damage.
REVISION:
Form No. 3308925.019 7/05
(Replaces 3308925.001)
©2005DometicCorporation
LaGrange,IN46761
Important:Theseinstructionsmuststaywith
unit. Owner read carefully.
RECORDTHISUNITINFORMATIONFOR
FUTUREREFERENCE:
Model Number
Serial Number
Date Purchased

2
INSTALLATION AND OPERATING INSTRUCTIONS
SAFETY INSTRUCTIONS
This manual has safety information and instruc-
tionsto helpusers eliminateor reducethe riskof
accidentsand injuries.
RECOGNIZE SAFETY INFORMATION
Thisisthesafety-alertsymbol.Whenyousee this
symbolinthis manual,bealert to thepotentialfor
personalinjury.
Follow recommended precautions and safe op-
eratinginstructions.
UNDERSTAND SIGNAL WORDS
Asignal word ,WARNING ORCAUTION isused
withthesafety-alertsymbol.Theygivethelevelof
riskforpotentialinjury.
indicates a potentiallyhazard-
oussituation which, ifnotavoided, couldresultin
deathorseriousinjury.
indicates a potentially hazard-
ous situation which, if not avoided may result in
minorormoderateinjury.
used without the safety alert
symbol indicates, a potentially hazardous situa-
tion which, if not avoided may result in property
damage.
Readandfollowallsafetyinformationandinstruc-
tions.
!
WARNING
!
CAUTION
CAUTION
!

3
INSTALLATION AND OPERATING INSTRUCTIONS
GENERAL INFORMATION
A. Thisairconditionerisdesignedfor:
1. Installationonarecreationalvehicleduringorafter
thetimethe vehicleismanufactured.
2. Mountingontheroofofarecreationalvehicle.
3. Roofconstructionwithrafters/joistsonminimumof
400mmcenters.
4. Minimum of 25mm and maximum of 100mm dis-
tancebetweenrooftoceilingofrecreationalvehicle.
Alternate installation methods will allow for roofs
more than 100mm thick.
B. Theabilityoftheairconditionertomaintainthedesired
insidetemperaturedependsontheheatgainoftheRV.
Somepreventativemeasurestakenbytheoccupantsof
the RV can reduce the heat gain and improve the
performance of the air conditioner. During extremely
highoutdoortemperatures,theheatgainofthevehicle
may be reduced by:
1. Parking the RV in a shaded area
2. Usingwindowshades(blindsand/orcur tains)
3. Keeping windows and doors shut or minimizing
usage
4. Avoidingtheuseofheatproducingappli ances.
5. OperationonHighFan/Coolingmodewillgiveopti-
mumormaximumefficiencyinhighhumidityorhigh
outsidetemperature.
6. Startingtheairconditionerearlyinthemorningand
SPECIFICATIONS
TYPE NOMINAL ELECTRICAL COMPRESSOR COMPRESSOR FAN MOTOR FAN MOTOR REFRIGERANT HEATERAMPS
NO. CAPACITY RATING RATED LOAD LOCKED RATEDLOAD LOCKED R-22 AT
WATTS KW ROTOR KW ROTOR GRAMS/OZ 220/240VAC
COOLING KW KW
B3351.531 3,245 1.1/ 1.2 4.5/ 5.0 0.21 0.46 510/18.0 1.64
220/ 240VAC,
50HZ.,1PH.
givingita"headstart"ontheexpectedhighoutdoor
ambient will greatly improve its ability to maintain
thedesiredindoortemperature.
7. Foramorepermanentsolutiontoahighheatgain,
accessorieslikeoutdoorpatioandwindowawnings
will reduce heat gain by removing the direct expo-
suretothe sun.Theyalsoadd aniceareato enjoy
companyduringthecooloftheevening.
C. Condensation
Note:Themanufacturer of thisair conditionerwill notbe
responsiblefordamagecausedbycondensedmoistureon
ceilings or other surfaces. Air contains moisture and this
moisture tends to condense on cold surfaces. When air
enters the RV, condensed moisture may appear on the
ceiling, windows, metal parts, etc. The air conditioner
removesthismoisturefromtheairduringnormaloperation.
Keepingdoorsandwindowsclosedwhenthisairconditioner
is in operation will minimize condensed moisture on cold
surfaces.

4
INSTALLATION AND OPERATING INSTRUCTIONS
PRECAUTIONS
INSTALLATIONINSTRUCTIONS
Improper installation may damage equip-
ment, could endanger life, cause serious
injury and/or property damage.
WARNING
!
A. Read installation and operating instructions carefully
before attempting to start your air conditioner installa-
tion.
B. DometicCorporationwillnotbeliableforanydamages
orinjuryincurredduetofailureinfollowingtheseinstruc-
tions.
C. Installation must comply with the National Electrical
CodeandanyRegionorLocalCodesorregulations.
D. DO NOT add any devices or accessories to this air
conditioner except those specifically authorized by
Dometic.
E. Thisequipmentmustbeservicedbyqualifiedpersonnel
andsomeregionsrequire thesepeopleto belicensed.
CHOOSING LOCATION FOR THE
AIR CONDITIONER
Thisairconditionerisspecificallydesignedforinstallationon
theroofofarecreationalvehicle(RV).
It is the responsibility of the installer of this
air conditioner/heat pump system to ensure
structural integrity of the RV roof. Never cre-
ate a low spot on the roof where water will
collect. Water standing around the air con-
ditioner/heat pump may leak into the interior
causing damage to the product and the RV.
CAUTION
A. NORMALLOCATIONS:
Theairconditionerisdesignedtofitoveranexistingroof
vent opening. When the vent is removed, it normally
creates a 360mm x 360mm opening.
B. OTHERLOCATIONS:
When no roof vent is available or another location is
desired,thefollowingisrecommended:
1. Foroneunitinstallation: Theairconditionershould
bemountedslightlyforwardofcenter(fronttoback)
and centered from side to side. See FIG. 1.
FIG. 2
L
2/3L
1/3L
It is preferred that this air conditioner be installed in a
relativelyflatandlevelroofsectionmeasuredwiththeRV
parked on a level surface; however, up to 15oslant to
either side, or front-to-back, is acceptable.
C. AFTERLOCATIONSELECTION:
1. Checkforobstructionsintheareawhereaircondi-
tioner will be installed. See FIG. 4.
2. Theroofmustbedesignedtosupport60Kg.when
the RV is in motion. Normally a 90 Kg. static load
designwill meetthis requirement.
c. Check inside the RV for air box obstructions. (i.e.
door openings, room dividers, curtains, ceiling fix-
tures, etc.) See FIG. 3.
871mm
325mm
750mm
510mm
570mm
60mm
FIG. 3
FIG. 1 1/2L L
2. Fortwounitinstallations:Installoneairconditioners
1/3andoneairconditioner2/3'sfromfrontofRVand
centered from side to side. See FIG. 2.

5
INSTALLATION AND OPERATING INSTRUCTIONS
ROOF PREPARATION
A. ROOFVENTREMOVAL:
1. Unscrewandremovetheroofvent.
2. Removeallcaulkingcompoundaroundopening.
3. Seal all screw holes and seams where the roof
gasket will be located. Use a good grade of all
weathersealer.
B. NEWOPENING:
(Installations Other Than Vent Openings)
FIG. 4
Rear
of
Unit
194mm
360mm x 360mm
Opening
460
mm
75mm
75mm
285
mm
285
mm
510mm
194mm
133
mm 378
mm
Front
of
Unit
1. A360mmx360mmopeningmustbecutthroughthe
roof and ceiling of the RV. It is recommended this
openingbelocatedbetweenroofreinforcingmem-
bers.
2. Mark a 360mm x 360mm square on the roof and
carefullycutthe opening.
3. Usingtheroofopeningasaguide,cutthematching
hole in the ceiling. See FIG. 4. 5. Route a copper 1.5mm2 with ground, supply line
from the fuse or circuit breaker box to the roof
opening.
a. The power supply must be on a appropriately
fused circuit.
360
mm
FIG. 5
20mm
Min. Frame
Opening Provide
Hole For
Wiring
90mm 90mm
90mm
90mm
360x 360mm
Cut Out
FIG. 6
There may be electrical wiring between the
roof and the ceiling. Disconnect 220-240volt
AC power cord and the positive (+) 12 volt
DC terminal at the supply battery. Failure to
follow this instruction may create a shock
hazard causing death or severe personal in-
jury.
WARNING
!
C. OPENINGPREPARATION:
1. Iftheopening exceeds365mmx 365mm,it willbe
necessary to install spacers.
2. Iftheopeningislessthan355mmx355mm,itmust
beenlarged.
3. The opening must be framed to provide adequate
supportandprevent airfrom beingdrawn fromthe
roofcavity. Lumber 20mm thickor moreand long
enough to bridge the opening must be used. Re-
memberto provideanentrance holefor thepower
supply wire. See FIG. 5.
4. In addition to the frame, the opening must be
reinforced with (10 mm or more thick) strips of
plywoodatleast 90mmwidearoundall4sidesofthe
cutouthole.Thiswillhelpprovidestrengthtoaccept
thewoodscrewsneededtosecuretheairbox.The
strips must be glued in place onto the ceiling
material. See FIG. 6.
Itistheresponsibilityoftheinstallerofthisair
conditioner system to ensure structural in-
tegrityoftheRVroof.Nevercreatealowspot
on the roof where water will collect. Water
standingaroundtheairconditionermayleak
intotheinteriorcausingdamagetotheprod-
uct and the RV.
CAUTION

6
INSTALLATION AND OPERATING INSTRUCTIONS
b. Wiring must comply with all National, Region
andLocalwiring codes.
c. Makesureatleast255mmofwireextendsinto
the roof opening. This insures easy air condi-
tionerattachment.
d. Ifventfanwasremoved,theexistingwiremaybe
usedprovided itisof propersizeand correctly
fused.
PLACING THE AIR CONDITIONER ON
THE ROOF
Thiscompletestheoutsidework. Minoradjustmentscanbe
donefromtheinsideifrequired.
DISCHARGE DUCT AND CEILING
TEMPLATE INSTALLATION
A. Removeairboxandmountinghardwarefromcarton. The
upperductisshippedinsidethelowerductwhichispart
of the ceiling template.
1. Removeupperductfromceilingtemplateandlocate
itoverblowerdischarge.
2. Usetwo(2) #10x10mm screws(C)toholdductto
basepan.Holesareprovidedinbottomofbasepan
forthese screws.
Note:EdgeswithoutflangesinstalltowardREARandSIDE
ofopening. SeeFIG.9.
B. Place the air conditioner on the roof. B. Measure(SeeFIGS.9&10)theceilingtoroofthickness:
1. Ifdistanceis25-50mm,removeperforatedtabsfrom
bothupperandlowerducts.
2. Ifdistanceis50-75mm,removeperforatedtabsfrom
bottom duct only.
3. Ifdistance is75-100mm, installducts asreceived.
C. Check for correct alignment and adjust the unit as
necessary(RoofGasketcentersover360mmx360mm
opening).
D. Reachupintoreturnairopeningoftheairconditionerand
pull the unit electrical cord down for later connection.
See FIG. 10.
This unit weighs approximately 45 Kg. To
prevent back injury, use a mechanical hoist
to place air conditioner on roof.
CAUTION
FIG. 7
Recycle All
Cardboard
Lift And Place
Do Not Slide
FIG. 8
Front
A. RemovetheAirConditionerfromthecartonanddiscard
the carton. See FIG. 7.
D. PlacetheAirBox Kitinside theRV. This boxcontains
mounting hardware for the air conditioner and will be
used inside the RV. See FIG. 7.
Do not slide the unit. This may damage the
neoprenegasketattachedtothebottomand
create a leaky installation.
CAUTION
C. Liftandplacetheunitoverthepreparedopeningusing
thegasketasaguide.Sealunderthegasketwithsilicon
sealant.Thecondensercoilgoestoward
the rear of the RV. See FIG. 8.
FIG. 9
GASKET
CENTER A /C
FROM BEL OW
M
EASURE
C
EILING
T
HICKNESS PULL DOW N
ELECTRICAL CORD
FIG. 10

7
INSTALLATION AND OPERATING INSTRUCTIONS
E. Installceilingtemplatebyslidinglowerductoverupper
duct.
F. Starteachmountingboltbyhandbeforetighteningany
ofthem.Thefour(4)threadedinsertsinthebasepancan
be seen to aid in starting the bolts.
G. Useabatterydrill andrun all4 boltsup until theytouch
the template but are not tight.
H. With the ceiling template flat against the ceiling install
the 6 wood screws at an angle, so as to stretch and
flattenthetemplate.Threeacrossthefrontand3across
the back of the template. See FIG.. 11.
WIRING OF SYSTEM
Note: All wiring must comply with the National Electrical
CodeandanyRegionorLocalCodesorregulations.
(Steps A. - F refer to FIG. 13- FIG.14.)
WARNING
!
Disconnect 220-240 volt AC. Failure to fol-
low these instructions could create a shock
hazard causing death or severe personal
injury.
FIG. 11
Wood
Screws
Knobs
I. EVENLYTIGHTENTHE4MOUNTINGBOLTSTOA
TORQUE OF 4.5 to 5.7 Nm.
This will compress the roof gasket to approximately
10mm. Theboltsareselflockingsoovertighteningis
not necessary. See FIG. 12.
If bolts are left loose there may not be an
adequateroofseal orifovertightened,dam-
agemayoccurtotheairconditionerbase or
ceiling template. Tighten to torque specifi-
cations listed in this manual.
CAUTION
FIG. 12 Evenly Tighten
The 4 Mounting
Bolts To 4.5 - 5.7
Nm
WARNING
!
This product is equipped with a 3-wire
(grounded) system for protection against
shock hazard. Make sure that the appliance
is wired into a properly grounded AC circuit
and the polarity is correct. Failure to do so
couldresult in death, personal injury or dam-
age to the equipment.
A. Route supply line into junction box through provided
Connector. 150mmleadsaresufficientforconnection
to unit wires and ground screws.
B. Connect RED wire in junction box to RED wire from
supply line.
C. Connect BLACK wire in junction box to BLACK wire
fromsupply line.
D. Connectsupplygroundwiretoidentifiedgroundscrew
in junction box.

8
INSTALLATION AND OPERATING INSTRUCTIONS
E. Installjunctionboxcoverwithtwo(2)#10x10mmblunt
point screws. See FIG. 14.
F. Plug air conditioners electrical cord into the mating
connectoron control box.
INSTALL AIR BOX
A. Removereturnairgrillefromairboxbypullinginonhalf-
roundfingercatches.
B. Holdairboxuptoceiling templateandinstallthree (3)
#10 x10mmscrewsatairboxmountingpoint.SeeFIG.
15.
C. Snapholeplugintoplaceatrearofairbox.SeeFIG.16.
FIG. 15
Install 3 Screws In to
Metal Template
E. In the event that the wood screws used to hold the
plastic air box to the ceiling do not grip or strip in the
ceilingmaterial,fourceilinghollowwallanchorscanbe
used.
F. Removetheplasticairboxanddrill8mmdiameterholes
in the location of the 4 screws. Install the hollow wall
anchors(notsuppliedandfollowmanufacturershollow
wall anchor installation instructions). See FIG. 18.
FIG. 16
Wood
Screw
HolePlug
Wood
Screw
D. Installfour(4)#8x16mm woodscrewsthatholdairbox
tighttoceiling.Handtightentopreventstrippingofthe
of the screw in the ceiling. Do Not Use a power screw
driver.See FIG.16 &17.
FIG. 17
Do Not Use Power Screw Driver To
Tighten Wood Screws
FIG. 18 Hollow Wall
Anchor
Ramset
HWD5M4
Hollow Wall Anchor
Compressed
G. Reinstall the plastic air box.
H. Place2 wireson topof thefoam filterpad fromcorner
to corner before placing the grill assembly into the air
box.Reinstallreturnairgrilleandfilterintoairbox.See
FIG.19.
I. Theairconditionerinstallationisnowcomplete. Turnon
power to the unit for operational check. Please read
UnitOperatingInstructionsbeforeproceeding.
FIG. 19 Place 2 Wires
From Corner To
Corner
Filter Grill

9
INSTALLATION AND OPERATING INSTRUCTIONS
OPERATINGINSTRUCTIONS
OFF
FAN
COOL
HEAT
COOLER
WARMER
LOW
MED
HIGH
HIGH
HIGH
MED
MED
LOW
LOW
®
CONTROLS
A. TheSelectorSwitchhas10 positionsincluding"OFF".
This controls fan speed, heating mode, and cooling
modes. See FIG. 20.
B. TheThermostatcontrolsthetemperaturerangefrom18°
Conthecoldestsideto32°Conthewarmestside.Inthe
cooling mode, the compressor ON/OFF controlled by
the thermostat setting.
COOLINGOPERATION
A. Setthe thermostatat thedesiredtemperature level.
B. Select the fan speed that best satisfies your needs:
1. HIGHCOOL: Selectedwhenmaximumcoolingand
dehumidificationrequired.
2. MED. COOL: Selected when normal or average
coolingrequired.
3. LOW COOL: Selected when room at desired
comfortlevelandneedstobemaintained. Normally
this speed used for night time operation.
Note: The blower runs continuously to circulate air and
maintainaneventemperature. Thecompressorwillcomeon
ascoolingisrequiredtomaintaintheselectedtemperature
level.
FIG. 20
HEATING OPERATION
Note: This electric heater will not replace a furnace for
heatingyourRVincoldweather. Theintentistoremovethe
chill on cool days or mornings.
A. Turnthethermostatto thedesiredtemperaturesetting.
B. Select the fan speed that best satisfies your needs:
1. HIGHHEAT:Selectedwhenmaximumheating
isrequired,
2. MEDIUMHEAT:Selectedwhennormaloraverage
heatingisrequired
3. LOWHEAT: Selectedwhenroomatdesiredcom-
fortlevelandneedstobemaintained.
FAN OPERATION
A. This will circulate the air in your RV without cooling or
heating. There are three positions: HIGH FAN, MED.
FAN or LOW FAN to select from, depending upon
personalchoice.
"OFF" POSITION
A. This is to turn Unit off.
MAINTENANCE
1. AIRFILTER:
Periodicallyremovethereturnairfilterlocatedabovethe
removablegrilleintheairbox. Washthefilterwithsoap
and warm water, let dry and then reinstall.
Note:Neverruntheairconditionerwithoutreturnairfilterin
place.Thismayplugtheunitevaporatorcoilwithdirtandmay
substantiallyaffecttheperformance ofthe unit.
2. AIRBOXHOUSING:
Cleanairboxhousingandcontrolpanelwithasoftcloth
dampenedwith a milddetergent. Never usefurniture
polishorscouringpowders.
3. FANMOTOR:
Factorylubricatedandrequiresnoserviceundernormal
use.
4. FROSTFORMATIONONCOOLINGCOIL:
Undercertainconditions,frostmayformontheevapo-
rator coil. If this should occur, inspect the filter and
cleanifdirty. Makesureairlouversarenotobstructed.
Airconditionershaveagreatertendencytofrostwhen
theoutsidetemperatureisrelativelylow. Thismaybe
preventedbyadjustingthethermostatcontrolknobtoa
warmer setting (counter clockwise). Should frosting
continue,operateonLOW,MED.orHIGHFANsetting
until the cooling coil is free of frost.

10
INSTALLATION AND OPERATING INSTRUCTIONS
SERVICE - Unit Does Not Operate
Ifyourunitfailstooperateoroperatedimproperly,check
thefollowingbeforecallingyourservicecenter.
1. If RV connected to motor generator, check to be sure
motorgeneratorisrunningandproducingpower.
2. IfRV connectedto powersupply bya landline, check
to be sure line is sized properly to run air conditioner
load and it is plugged into power supply.
3. Check your fuse or circuit breaker to see if it is open.
4. Aftertheabovechecks,callyourlocalservicecenterfor
furtherhelp. Thisunitmustservicedbyqualifiedservice
personnelonly.
Whencallingforservice,alwaysgivetheairconditioner
ModelNumberandSerialNumber. Thisinformationcan
be found on unit rating plate located on the base pan
near the return air opening. Return air grille must be
removedfromairboxtoview.

11
INSTALLATION AND OPERATING INSTRUCTIONS
3309270.001
MOTOR
GRN/YEL
5
6
2
3
4
1
7
2
3
GRN/YEL
BLK
YEL
RED
CAP
FAN
BRN
WHT
BRN
WHT
BLU
GRN/YEL
WHT
PTCR
START
CAP CAP
RUN
COMPRESSOR
C
RS
O.L.
WHT WHT
RED RED
ELECTRICAL BOX
HEATING ELEMENT
HEATING ELEMENT
9 PIN
9 PIN
3 PIN
3 PIN
1BLK BLK
LIMIT SWITCH
FAN
CONN
ELEC
1
2
3
4
5
6
1
2
3HEAT
TO ELEC
TO ELEC
LINE SPLICE
LINE SPLICE
FACTORY WIRING
FIELD WIRING
FIELD WIRING
220/240 VAC
220/240 VAC
50 HZ 1 PH
50 HZ 1PH
USE COPPER
USE COPPER
CONDUCTORS
ONLY
RED
3309275.000
3309275.000
ACTIVE(P)
NEUTRAL(P)
EARTH
3
1
2
THERMOSTAT
JUNCTION
BOX
GRY
L1
ROTARY
SWITCH
C H 4
2
1
7
ORN
YEL
RED
BLU
BLU
WHT
BRN
GRN/YEL
BLK
BLK
GRY
GRN/YEL
A/C
TO
9PIN
9PIN
3PIN
3PIN
AIRCONDITIONINGUNIT
A. (4) 180mm mountingbolts
B. (10) #8 x 16mm long sharp point wood screws
C. (7) #10 x 10mm blunt point tapping screws
D. (1) Connector
E. (1) Hole Plug
MOUNTINGPARTS
DischargeAir
Opening
Threaded Hole
InBottom
Framing Stock
ReturnAir
Opening
MountingBolt
UpperDischarge
Duct
DischargeAir
Duct
MountingBolt
Power Supply
Line
AIR BOX - CONTROLS
WIRINGDIAGRAM AIR CONDITIONER - WIRING DIAGRAM
FIG. 21 FIG. 22