Dometic 39626.501 User manual

1
INSTALLATION INSTRUCTIONS
APPLICATION MANUAL
AND
INSTALLATION INSTRUCTIONS
THIS UNIT IS DESIGNED FOR OEM INSTALLATION
ALL INITIAL INSTALLATIONS MUST BE APPROVED BY THE SALES DEPT.
ROTARYCOMPRESSOR
SYSTEM MODELS
Air Conditioners
39626.501&39626.506
Heat Pumps
39726.501&39726.506
SYSTEM
MODELS
SELF-CONTAINED
AIRCONDITIONER&HEATPUMP
FOR
RECREATIONALVEHICLES
REVISION:
FormNo.3308463.011 5/06
(Replaces3308463.003
(French3308477.011)
©2003DometicCorporation
LaGrange,IN 46761
WARNING
!
This manual must be read and un-
derstood before installation, adjust-
ment, service, or maintenance is
performed. This unit must be in-
stalled by a qualified service techni-
cian. Modification of this product
can be extremely hazardous and
could result in personal injury or
property damage
39626.501
39626.506 39726.501 39726.506
US
Important:Instructionsmuststaywithunit.
Owner read carefully
RECORDTHISINFORMATIONFORFUTUREREFERENCE
BEFOREINSTALLINGTHEUNIT:
ModelNumber
SerialNumber
Date Purchased
Place of Purchase
Lire et comprendre ce manuel avant de
procéderàl'installation,à desréglages,
de l'entretien ou des réparations.
L'installation de cet appareil doit être
effectuée par un réparateur qualifié.
Toute modification de cet appareil peut
être extrêmement dangereuse et
entraîner des blessures ou dommages
matériels.
AVERTISSEMENT
!
USA
SERVICEOFFICE
DometicCorporation
2320 Industrial Parkway
Elkhart,IN46516
574-294-2511
CANADA
DometicCorporation
46 Zatonski, Unit 3
Brantford, ON N3T 5L8
CANADA
519-720-9578
For Service Center
Assistance Call:
800-544-4881

INSTALLATION INSTRUCTIONS
2
TABLE OF CONTENTS:
1.0 SAFETY INSTRUCTIONS ...........................................................................PAGE 3
2.0 APPLICATION MANUAL .............................................................................PAGE 4
2.1 AIR DISTRIBUTION...........................................................................PAGE 4
2.2 HOW ROOM AIR IS RELATED TO OUTLET PERFORMANCE .....PAGE 7
2.3 SPECIFICATION AND REQUIREMENTS.........................................PAGE 7
2.4 HIGH-POT REQUIREMENTS............................................................PAGE 8
2.5 MOUNTING IN COACH......................................................................PAGE 9
2.6 WIRING DIAGRAM 39726.501 & 39726.506 .....................................PAGE 10
2.7 SPECIFICATIONS-HEAT PUMP .......................................................PAGE 10
2.8 WIRING DIAGRAM 39626.501 & 39626.506 .....................................PAGE 11
2.9 SPECIFICATIONS - AIR CONDITIONER .........................................PAGE 11
3.0 INSTALLATION MANUAL ...........................................................................PAGE 12
3.1 GENERAL INSTRUCTIONS..............................................................PAGE 12
3.2 PROCEDURE ....................................................................................PAGE 12
3.3 ELECTRICAL WIRING ......................................................................PAGE 14
3.4 CONTROL SYSTEM WIRING ............................................................PAGE 14
3.5 SYSTEM CONFIGURATION AND CHECK OUT ..............................PAGE 16

3
INSTALLATION INSTRUCTIONS
1.0 SAFETY INSTRUCTIONS
This manual has safety information and instruc-
tionstohelpuserseliminate or reduce the risk of
accidentsandinjuries.
RECOGNIZE SAFETY INFORMATION
Thisisthesafety-alertsymbol.Whenyouseethis
symbolin this manual,be alert tothe potential for
personalinjury.
Follow recommended precautions and safe op-
eratinginstructions.
UNDERSTAND, SIGNAL WORDS
Asignalword, WARNING OR CAUTIONis used
withthesafety-alertsymbol.They givethelevelof
riskfor potentialinjury.
indicatesa potentiallyhazard-
oussituationwhich, ifnotavoided, couldresultin
deathor seriousinjury.
indicates a potentially hazard-
ous situation which, if not avoided may result in
minoror moderateinjury.
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
!

INSTALLATION INSTRUCTIONS
4
2.1 AIR DISTRIBUTION
2.1.1 GENERALINFORMATION
The purpose of an air conditioning system is to provide
environmental conditions in a space to keep its occupants
comfortable.
Thebasicelementsofasimpleforcedcirculationairsystem
consistsofacoolingunit,acentrifugalblower,atemperature
sensingdevicecontrollingoperationofthecompressorand
blower, suitable air filters, and a duct system.
Airisfiltered,cooled,anddistributedtovariousareasofthe
vehicle. Duct work should deliver this conditioned air as
directly, quietly, and economically as possible. If the
distributionisnotproperlysizedandbalanced,flowofairwill
notbeascalculatedandthesystemwillnotfunctionproperly
orefficiently.
2.1.2 THEBASICAIRCONDITIONING
CYCLE
Thecomponentswhicharebasictoairconditioningsystems
areillustratedbyFigure2.1. Airistreatedattheconditioning
unit,transferredtotheconditionedspacethroughthesupply
ductsystemandreturnedtotheconditioningunitthroughthe
returnsystem. Theductsystemsarealsoreferredtoasthe
distribution system.
2.1.3 FUNCTIONOFADUCTSYSTEM
Aductisatube,orpipe,thatcarriesairbetweentwopoints.
Strictlyspeaking,inairconditioningterms,aductsystemis
the arrangement of ducts between air conditioning equip-
ment and rooms to be cooled, not including such items as
filters,coolingcoils,etc. However,weshallincludeinouruse
of the term “duct system”, every item in the air-passage
networkthatoffersresistancetoairflow.Fromthestandpoint
ofthebloweritmakesnodifferencewhetheraresistanceis
causedbyfilters or by theuseof a small duct;effect will be
thesame. Resistancetendstorestrictflowofairthroughthe
entire system.
A forced air system is only as good as its air delivery
system. Comfort levels are affected by the quantity and
velocity of air movement within the space and the proper
mixingofthesupplyairwiththeroomair. Supplyairshould
befurnishedinamannerthatwilldirecttheairtothesources
ofthegreatestheatlossand/orheatgain.Theeffectsofthe
gain or loss can then be offset by the supply air. It is
importantthattheselectionofthediffusersandgrillsforthe
supplyandreturnsystemsreceivecarefulattentiontoenable
them to accomplish their purpose.
Considerationmustbegiventoallaspectsofthesupplyair
distribution patterns: throw, spread, drop, etc. Also, the
outletandreturngrillevelocitiesmustbeheldwithinreason-
able limits. Any noise generated at the grille is equal to or
greaterin importance thanduct noise.
Awindowairconditioner(Figure2.2)isessentiallyadevice
withaminimumductsystem,sincetheonlyitemsthatoffer
resistance to air flow are built into the cabinet.
2.1.4 FACTORSAFFECTINGRESISTANCETOAIR
FLOW
Common observations of daily events tell us something
aboutfactors affecting resistanceto air flow. Weknow,for
example,thatmorepressureisrequiredtoforceagivenrate
ofairflowthroughasmallductthanthroughalargeduct. We
alsoknowthatstreamliningofductsmeanslessresistance
toairflow, and thatsharpangled turns must beavoided.
Asairpassesthroughducts,coolingcoils,grilles,diffusers,
anddampers,the staticpressureis reducedbyfrictionand
turbulencelosses.Goodductdesignminimizestheneedto
balance the duct system by sizing the ducts such that the
designedpressuredropallowsthedesiredairflowratetobe
deliveredtoeachroom.Animproperlysizedductsystemwill
require extensive balancing. Balancing is a procedure by
whichtheairflowallotmentisadjustedtosupplythecorrect
quantity of conditioned air to each room.
2.0.0 APPLICATION MANUAL
Block diagram of comfort air conditioning cycle.
Arrows indicate direction of air flow.
FIG.2.1
EVAP
AND
FAN
COMPRESSOR,
CONDENSER
ANDFAN OUTDOORS
WARMROOMAIR
TOBECOOLED
OUTDOORAIRTO
CONDENSER
FIG. 2.2
The Window Air Conditioner represents a minimum duct sys-
tem, since air to and from the cooler is handled without external
ducts.
HEATEDAIRFROM
CONDENSERDISCHARGED
OUTDOORS
COOLAIRDISCHARGE
INTOROOM
ROOM
CONDITIONING
UNIT
SUPPLY DUCT
SYSTEM
RETURN DUCT
SYSTEM
CONDITIONED
SPACE

5
INSTALLATION INSTRUCTIONS
2.1.5 AIRFLOWANDFRICTION
Airflowsin a ductsystemfrom a region ofhigh pressure to
aregionoflowerpressure. Theblowercreatesthepressure
differential which causes the air flow through the duct
system. Thepointofhighestpressureinthesystemisatthe
outlet of the blower. The point of lowest pressure in the
systemisatthereturnopeningoftheblower.Theairpressure
constantly decreases as the air flows through the system.
The pressure ultimately diminishes to zero as it passes
through the register and is diffused into the conditioned
space. Asairmovesthroughaduct,apressuredropoccurs
dueto thefriction betweenthe airand thewalls ofthe duct.
Anotherfactor inpressure dropis theturbulence withinthe
airstream itself. Airmovingwithinaduct doesnot flowin a
placidstream. Ratheritmovesinachurningandmixingpath,
or“turbulent flow.”Thecumulative effectof rubbingfriction
andturbulencefrictionisfrictionloss. Airturbulenceinaduct
systembecomessubstantialwheneverthereisachangein
thedirection ofair flow.
2.1.6 ECONOMICSOFDUCTDESIGN
Inordertomatchtothesystemairdeliverycapacity,elbows
forturningtheairmustbekeptaslargeasallowedbytheunit
construction. Duct depth for Dometic air conditioners
may vary with each model series. Confirm the system
to be installed and refer to Figure 3.4, for specific duct
configurationsrequired.Highlosselbowsmusthavetheir
resistance lowered by the use of splitters or turning vanes.
RefertoFigure2.3through2.7.
Another factor in duct losses is air leakage. Although
leakage is not considered in duct design it should be an
installationconsideration.Coldairleakingintothesurround-
ing cavity will cause condensation to form under high
humidity conditions. Sealing all joints will assure moisture
free cavities and maximum distribution of air to the outlets.
In most cases of high resistance encountered in duct
systems, one or more of the following points have been
overlookedbytheinstaller:
A. Small Diameter
Pressure losses increase as diameter of a duct is
reduced. Gooddesignpracticeisthatwhichenablesthe
installer to put in the smallest size duct that will do the
job of delivering required airflow rate with pressure
available. Nosinglesizeofductwillprovetobeidealfor
all jobs.
B. Length of Duct
Pressure loss increases as duct length is increased.
Thisisalmostobvious;aductwhichis6ft.longhastwice
the pressure loss of one that is 3 ft. long, provided that
bothducts arethe samesize andbotharecarryingthe
sameairflowrate.
C. Changes in Direction (Figure 2.7)
Pressure losses increase when direction of air flow is
changed. Whenairisforcedtomakea90°turninaduct
system,pressurelossismuchgreaterthanforastraight
runofthe samelength.(Refer to FIG.2.7)
Item1. Thissharp-angledbendcausesalargepressure
loss. Asimpleway ofvisualizingsuch pressurelossis
toimaginethatthesediagramsrepresenthighwayson
whichyouaredrivingacar. Asyouapproachabendyou
areforcedtoslowthecarspeedto15mph. Insodoing,
aconsiderablepartofenergyofthefast-movingcarhas
hadtobeabsorbedbythebrakes. Theanalogyholdsfor
airparticlesflowingaroundasharpbend.
Item 2. This sharp-angled bend on the inside corner
causesgreatpressureloss. Theroundedcorneronthe
outsidedoesnothelpasmuchasmightbeanticipated.
Item 3. This is a common form of 90° bend that has
relativelylowresistance.
Item 4. Ifminimumresistanceisdesired,thisextreme
example of a smooth, streamlined fitting can be used,
althoughspacerequirementswillbeprohibitiveinmany
installations.
Item5. Occasionally,abeamorrafterpreventstheuse
ofasmooth bend and arightangle bend is necessary.
Insuchcasestheuseofturningvanes(splitters)willbe
effectiveinreducingresistance.
Item 6. Anotherwaytoreduceresistance istochange
item (3) to a modified version of item (4) by inserting
splitters in the sharper bend.
D. Sudden Contraction
When air is suddenly contracted from a large duct to a
small duct, a pressure loss occurs See Figure 2.8.
E. SuddenExpansions
Thepressurelossresultingfromthesuddenexpansion
ofair fromasmall ductto alarge duct,aremuch larger
thanlossesduetosuddencontraction. Aswithsudden
contraction,muchcanbedonebymakingairexpansion
gradual,ratherthanabrupt.SeeFigure2.9.
TosummarizeSection2.1.6,thefollowingitemscontrib-
ute to higher pressure losses in a duct system:
1. Smaller diameter ducts
2. Longer duct lengths
3. Changes in direction of air flow

INSTALLATION INSTRUCTIONS
6
ITEM 1
Sharp Angle ITEM 4 Long Radius Bend
ITEM 2
Rounded
Outer
Corner
ITEM 5
Splitters, or turning vanes
installed in sharp angle
bend
ITEM 3
Rounded
Corners
ITEM 6
Splitters in rounded
corner bend
EDDIES
EDDIES
ABRUPT EXPAN-
SION
SMALL
DUCT
EDDY
LOSSES
LARGE
DUCT
FIG. 2.9
Abruptexpansionresults in excessivepressure losses.
R
W
D
R
W
RR =
Radius Ratio (RR)
or RR = 1.5
FIG. 2.4
PREFERRED
(Standard) FAIR
POOR NOT ACCEPTABLE
Various Elbows Showing Radius Ratios
FIG. 2.3
Rb
Ra
D
WCR = Ra
Rb
CurveRation(CR)
Optimum Reading CR = .05
FIG. 2.5
Ra
R
Rb
Rb Ra
1
R
R2
1
CR =
R1 = 2 Ra
CR = .25
CR =
R1 = 2 Ra
R2 =
CR = .15
Ra
Rb
Ra
Rb
(Rb - R1)
2+ Ra
FIG. 2.6Using Splitters to reduce resistance.
FIG. 2.7
Different ways of making a 90 degree bend. Some
involve greater pressure losses than others.
FIG. 2.8
Pressure losses occur with abrupt reducing fittings.
ABRUPT
CONTRACTION
SMALL
DUCT
LARGE DUCT
EDDY
LOSSES

7
INSTALLATION INSTRUCTIONS
4. Sudden contractions in air stream
5. Sudden expansions in air stream
2.1.7 REGISTERS,DIFFUSERS, AND GRILLESELEC-
TION
One of the most important considerations in designing a
conditioningsystem istheselection ofthe registers,diffus-
ers and grills. Even though a system delivers the required
amount of conditioned air to the room, discomfort results if
the air is not satisfactorily distributed. Achieving good air
distribution is as much an art as it is a science. Careful
considerationmustbegiventothedesignoftheairdistribu-
tion system. A forced air system is only as efficient as its
airdeliverycomponents.
Whenever a jet of conditioned air is admitted into a room it
affectsalltheairwithinthatroom.Movementofthesupplyair
inducesadjacentroomairtomovealongwithit. Thisprocess
of thesupplyairdraggingalongtheroomairandsettingitin
motionis called“entrainment”oftheroom air. Asthe room
air mixes with the supply air, the temperature difference
between them is reduced. This effect is even more pro-
nouncedwithaspreadingjetthanwithanon—spreadingjet
becauseofthegreatersurfacearea.
2.1.8 ROOMAIRDISTRIBUTION
Thefinalevaluationofairdistributioninaspaceisdetermined
by the occupants’ comfort level. In general, a person is
thermallycomfortablewhentheirbodyheatlossjustequals
theirheatproduction.
Duringcooling,currentscarrywarmairupthewalltoceiling
level, and stratification forms from the ceiling down. The
solutionistoprojectcoolairintothisregionneartheceiling.
Performanceofanysupplyoutletisrelatedtoinitialvelocity
andarea. Asitleavestheoutlet,anairjetbecomesamixture
of supply and room air, expanding due to the induction of
roomair.
Thebuoyantforceswithnon-isothermaljetscausethejetto
rise during heating and drop during cooling. If the jet is
projectedparalleltoandwithinafewinchesofasurface,the
jetperformancewillbeaffectedbythesurface,whichlimits
theinductiononthesurfacesideofthejet.Thiscreatesalow
pressureregionbetweenthejetandthesurface,whichdraws
thejettowardthesurface. Infact,thiseffectwillprevailifthe
angleofdischargebetweenthe jetandsurfaceisless than
40°. Thesurfaceeffectwilldrawthejetfromaceilingoutlet
totheceiling.Surfaceeffectincreasesthethrowforalltypes
ofoutletsanddecreasesthedropforhorizontallyprojected
air streams.
Theairstreamfromtheoutlettendsto“hug”thesurface.As
a matter of fact, this characteristic is almost essential for
goodcomfortairconditioning.Therefore,ratherthantryingto
direct the air away from surfaces, the surfaces should be
used intentionally. Note that where the surfaces are used
mosteffectively,the highvelocityportionsoftheairstream
havelesstendencytoentertheoccupiedzoneofthespace.
2.2 HOWROOM AIRMOTIONIS RELATEDTO
OUTLETPERFORMANCE
Theroomair near thesupply air stream isentrained by the
air stream and, in turn, is replaced by other room air. The
room air always moves toward the supply air. The only
general statement that can be made regarding room air
motion and the number of air changes is that 8 to 10 air
changesperhourarerequiredtopreventformationofstag-
nantregions.
For most applications, a better approach is to supply air in
such a way that the high velocity air stream from the outlet
doesnotentertheoccupiedzone. Itispracticaltoconsider
the region within 12 inches of the walls as outside the
occupiedzoneaswellastheregionabovetheheadsofthe
occupants.
Supplyairshouldbespreadinathinlayeroverthesurfaces,
tosurroundtheoccupiedzonewithconditionedair. Airwithin
theoccupiedzonewillthenmovetowardthetotalairstream,
themixtureofprimaryandroomair.Theroomaircarriesthe
load with it into the air stream and room conditions are
maintained by constant mixing of room and supply air.
Improperinstallationmaydamageequipment,
couldendangerlife,causeseriousinjuryand/
or property damage.
WARNING
!
It is the responsibility of the R.V. manufac-
turertoassurethatstructuralintegrityismain-
tained throughout the coach.
CAUTION
2.3 SPECIFICATIONS&REQUIREMENTS
Since it is necessary to install all or part of the duct work in
theceiling,sidewall or floor.
Themanufacturershouldrevieweachfloorplantodetermine
properductdesignand registerlocation.
The Dometic Product Engineering and Application depart-
mentsareavailableforrecommendationsandsuggestions.
If the conditioned air is to be discharged from the
ceiling area, the minimum roof cavity thickness for
proper installation measured between the roof and
ceiling structure is 4 inches. This does not include
space required for insulation of the ductwork.
Theairconditionerwasdesignedtoallowflexibilityforlayout
ofductworkandthetypesofregistersemployed.Toensure
airconditionermaximumperformance,certainparameters
mustbeadheredto.RefertoFigures3.4forductsizingand
grillplacement

INSTALLATION INSTRUCTIONS
8
It is the responsibility of the installer to en-
sure the duct work will not collapse or bend
during and after installation. Dometic Corpo-
rationwillnot beliableforany structural dam-
age due to improperly insulated, sealed or
collapsed duct work.
CAUTION
Dometic Corporation will not be held liable
for roof structural or ceiling damage if the
duct work is not adequately wrapped in an
insulation blanket.
CAUTION
2.3.1 COOLINGREQUIREMENTS
Whendeterminingthecoolingrequirementsofeachvehicle,
thefollowingshouldbeconsidered:
A. Thesizeofthevehiclewilldeterminethenumberof
airconditioningunitsthatarerequired,ortheneed
topre-wireforadditionalairconditionersdepending
onthegeographicallocationof use.
B. Amount of insulation in walls, floor and roof of the
vehicle.
C. Identifypossibleheatsourcesandplanaccordingly:
1. Skylights-locationshouldnotbewithin4feetof
the air conditioner return system.
2. Skylights - should be tinted and double pane.
3. Roofvents shouldbe atinted type,andquan-
tity kept to minimum.
4. Increaseduseofslide-outsand/orglasssquare
footagewillrequiretintingwith additional
insulation in wall and ceiling cavities.
5. Calculationofheatproducingappliances.
2.3.2 AIRDISTRIBUTIONSYSTEMSIZING
Basement systems are designed exclusively with external
ductworkforthe coldairdischarge. Therearenotprovi-
sions for an electric heater to be installed as part of the
unit. The central furnace will supply heating of the
vehicle,ifinstalled.
Thecondensersectionmustbeinstalledsoastohavedirect
access to the outside ambient. Removal of the heated
condenserairiscriticalforproperoperation.
The installer of this air conditioner must design the air
distributionsystemforhisparticularapplicationbyfollowing
the guidelines specified within this application manual and
unitinstallationinstructions.Several specificrequirements
MUST BE met for the air conditioner to operate correctly:
1. Unit Total Static Pressure See Figure 2.10.
2. DuctAreaRequirement.SeeFigure2.10.
3. Returnairtothesystemmustbefilteredtoprevent
dirtaccumulationontheevaporatorcoolingsurface.
4. Returnairopeningmustbewithinminimumsspeci-
fied in the system installation instructions. This
figure must include the filter material selected.
5. Since duct work is located within a cavity, it is
necessarythatallductworkmustbewrappedwith
a minimum R7 insulating blanket with a vapor
barrier. This will help prevent heat gain within the
ductandpossiblecondensation.
2.3.3 AIR DISTRIBUTIONDUCTPREPARATION
Dependingonthedistributionconfiguration,ensurethatthe
airentrypointshavetheminimumsquareinchesrequiredfor
theseriesofsysteminstalled.SeeFigure3.4forpermissible
ductlayout.Ductelbowsand/orrestrictionsmustbekeptto
a minimum. The duct must be pre-built within the structure
and sealed along its entire length. If joints or bends leak
conditionedair withinthe cavity,condensationwillform.
Whentheductisinstalledwithinthestructure,care mustbe
takentoinsurethatthe ductwillnotcollapseorbendduring
or after installation of the system to the vehicle.
2.3.4 LOCATIONOFDISTRIBUTIONDUCT
Thevehicleitselfandtheplacementofinteriorcomponents
willdictatethelocationoftheduct.Onemustbesurethatthe
registerswillnotfallnearthethermostatorthereturnfilters.
Theplacementmustbesuchthattheairdistributionfromthe
registerswillprovidethebestpossiblemovementwithinthe
livingarea.Calculationsshouldbemadeastothestrength
of the cavity, to insure structural integrity if notched for
location of the duct runs.
2.3.5 RETURNREQUIREMENTS
Thereturnairsystemmustbeconsideredwhenlayoutofthe
ductsystemisinprocess.Thisshouldbelocatedasnearto
thesystemaspossibletoinsureadequatereturnbacktothe
evaporatorcoil.
2.4 HI-POTREQUIREMENTS
EachsystemthatisbuiltbyDometiciscompletelychecked
electrically and hi-pot tested on our production line. Addi-
tional hi-pot testing of the system must not be done.
Disconnect the system from the power circuit prior to any
vehiclehighpotentialtestoperations.
System Duct Condenser Evap. Static
P/N Size Inlet Req. Inlet Req. Press
39626 3x15" 648in2135in20.40 - 1.20
39726 min.
5x16"
max.
FIG. 2.10

9
INSTALLATION INSTRUCTIONS
2.5.0 MOUNTINGINCOACH
The dual basement air conditioner and heat pump are
designed for under the floor installation. It is the vehicle
manufacturer'sresponsibilitytoprovideaninstallationspace
whichwillallowforcutoutsandmountingoftheunitwithout
cutting vital frame structures. The frame and structural
sectionsintheinstallationspacewillnotcauserestrictionof
airmovementrequiredbythedualbasementairconditioner
or heat pump. See Figures 2.11, 2.12 and 2.13.
2"
ImportantNotice
Allinformation containedwithinisfortheinstallationof DometicDuctedAirConditioners.
Theseguidelinesgiveminimumrequirementsforductsizing,ductarrangementandreg-
isterlocation sothatyou receivemaximumperformance fromthesystem.
These instructions DO NOT cover or warrant the
final installation of the duct work that carries
conditioned air within the ceiling cavity.
The installer is responsible for the integrity of the insulated duct within the structure to
insure that moisture laden air does not condense on duct surfaces. If proper practices
are not adhered to, condensation will collect during high ambient conditions. Damage
causedbycondensation will notbecovered by DometicCorporationwarranties.
FIG. 2.11
18"
2.75"
9.5"
9.5"
11.75"
9.31"
46"
18"
22 "
4.56"
Evaporator
Coil Evaporator
Drain Tube
Condenser
Discharge
Condenser
Coil Drain
4Holes
FIG. 2.12
18"
6.5"
5.5"
7.5"
5.75"
36"
7.5"
Electrical Box
WiringAccess
39626.501
39726.501
Top
Discharge
39626.506
39726.506
Side
Discharge
Condenser
Coil
6.5"
Suggested Placement
OfSupports
FIG. 2.13

INSTALLATION INSTRUCTIONS
10
System Model 39726.501 & 39726.506*
NominalBTUCapacity 26,000
Volts/Phase/Hertz (each circuit) 115 AC / 1 / 60
Run Amps Comp (Circuit 1 =10.0) (Circuit 2 = 9.8)
LRA Compressor (Circuit 1 = 59.0) (Circuit 2 = 59.0)
Total Blwr/Fan Motor Run Amps 8.5 (Circuit 1)
Total Blwr/Fan Motor LRA Amps 18.0 (Circuit 1)
Duct Static - Min. ( In. Water Column) 0.40
Duct Static - Max. ( In. Water Column) 1.20
Generator Size Per/Unit - Min. *** 7.5K
Wire Size (Up to 24 ft.)** (Circuit 1) No. 10 AWG Copper Conductors)
(Suggested) (Circuit 2) No. 12 AWG Copper Conductors)
Circuit Protection (Circuit 1) 25Amp
Time Delay Fuse or (Circuit 2) 15Amp
HACR Circuit Breaker
Control Voltage 12V DC
Refrigerant R-22
System Refrigerant Charge (Circuit 1 = 46.5) (Circuit 2 = 38.5)
Size (In Inches) Width Height Depth
46 18 22
Installed 205 Pounds
Weight
2.7 SPECIFICATIONS - HEAT PUMP
**
Models ending with .506 suffix and manufactured with "SIDE AIR DISCHARGE".
For wire lengths over 24 ft. consult the National Electric Code for proper sizing.
The Manufacturer gives only general guidelines for generator requirements. These generator
requirements come from experiences consumers have with our equipment in field applications.
When sizing the generator, the total electrical power must be taken into consideration. Keep in
mind that generators lose power because of altitude increases above sea level , high outdoor
temperatures and lack of maintenance.
*
***
2.6 WIRING DIAGRAM 39726.501 & 39726.506
VIO
BLK
VIO
BLK
RUN
CAP
CAP
START
COMP
STARTER
STARTER
CAP
START
COMP
HERM
C
USE COPPER CONDUCTORS
USE COPPER CONDUCTORS
WHT
G-Y
BLK
ONLY
115 VAC 60 Hz 1O
115 VAC 60 Hz 1O
CIR.#2
GRY
G-Y
ORN
BLKHD
GRY
WHT
GRY
ON
3 AMP FUSE
NATIONAL ELECTRIC CODE
NATIONAL ELECTRIC CODE
F1
USE COPPER CONDUCTORS
USE COPPER CONDUCTORS
BLK
ONLY
COMPLY WITH THE
COMPLY WITH THE
FIELD WIRING MUST
FIELD WIRING MUST
115 VAC 60 Hz 1O
115 VAC 60 Hz 1O
CIR.#1
P3
SENSOR
AMB.
P2
P1
G-Y
WHT
NC
NO
ORN
WHT
BOX
ELEC.
YEL
YEL
BLU
BLU
RED
BLK
P6
ORN
COM
WHT
BLK
MOTOR
CAP
BLK
ELEC.
BLKHD
BOX
BLK
NC
NO
FREEZE
CONTROL
P5P4
6
DIP SWITCHES
2
15
4
3
K1
8
7
COM
ORN T3
K6
T2
BOARD
CIRCUIT
T4
G-Y
G-Y
WHT
RED
T1
FAN
WHT
COND. BLOWER
COND. BLOWER
MOTOR
RED
BRN
CAP
RUN
HERM
BRN
WHT
BLK
= WIRE NUT
=WIRE NUT
FACTORY WIRING
FIELD WIRING
FIELD WIRING
BRN
COMPRESSOR
3108345.095
3108345.095
S
C
R
OL
COMPRESSOR
WHT
BRN
BRN
BRN
WHT
BLK
GRY
EVAP. COIL
EVAP. COIL
VIO
BLK
BLK
WHT
CWHT
RED
WHT
RED
RED
WHT
BRN
VIO
BLK
BRN
BLK
MOTOR
EVAP. BLOWER
EVAP. BLOWER
WHT
WHT
ORN
ASM
VALVE
REV.
REV.
ASM
OL
C
BLK
VALVE
REV.
RED
S
R
DIELECTRIC
PASSED

11
INSTALLATION INSTRUCTIONS
C
HERM
HERM
C
3108345.061
FIELD WIRINGFIELD WIRING
FACTORY WIRINGFACTORY WIRING
P4P3 P5
NC
P6
COM
K6
COM
NO
K1
F1
P1
P2
NO
T3
NC
T1
3 AMP FUSE3AMP FUSE
CIRCUITCIRCUIT
MOTOR
COND. BLOWERCOND. BLOWER
EVAP. BLOWEREVAP. BLOWER
MOTOR
COMPRESSOR
R
C
S
OL
COMPRESSOR
S
COL
R
= WIRE NUT=WIRE NUT
ELEC.
BOX
BLKHD
SENSORSENSOR
AMB.
COMP
RED
WHT
START
CAP
STARTERSTARTER
STARTER
COMP
START
CAP
RUN
CAP
CAP
RUN
T2
DIP SWITCHESDIP SWITCHES
12345678
ON
BOARD
GRY
GRY
BRN
BLK
ORN
G-Y
GRY
ORN
YEL
YEL
BLU
BLU
BLK
ORN
WHT
G-Y
BLK
RED
BLK
BLK
BLK
WHT
WHT
RED
WHT
BLK
BLK
WHT
REDRED
WHT
GRY
WHT
BRN
ORN
BLK
CONTROL
FREEZE
EVAP. COILEVAP. COIL
WHT
FAN
BRN
CAP
MOTOR
BRN
BRN
BRN
BRN
WHT
BRN
RED
RED
WHT
WHT
ORN
RED
USE COPPER CONDUCTORSUSE COPPER CONDUCTORS
WHT
G-Y
BLK
ONLY
CIR.#2
115 VAC 60 Hz 1 PHASE115 VAC 60 Hz 1PHASE
NATIONAL ELECTRIC CODENATIONAL ELECTRIC CODE
USE COPPER CONDUCTORSUSE COPPER CONDUCTORS
ONLY
FIELD WIRING MUSTFIELD WIRING MUST
COMPLY WITH THECOMPLY WITH THE
CIR.#1
115 VAC 60 Hz 1 PHASE115 VAC 60 Hz 1PHASE
BLK
G-Y
WHT
DIELECTRIC
PASSED
System Model 39626.501 & 39626.506*
NominalBTUCapacity 26,000
Volts/Phase/Hertz (each circuit) 115 AC / 1 / 60
Run Amps Comp (Circuit 1 = 10.1) (Circuit 2 = 9.8)
LRA Compressor (Circuit 1 = 59.0) (Circuit 2 = 59.0)
Total Blwr/Fan Motor Run Amps 8.5 (Circuit 1)
Total Blwr/Fan Motor LRA Amps 18.0 (Circuit 1)
Duct Static - Min. ( In. Water Column) 0.40
Duct Static - Max. ( In. Water Column) 1.20
Generator Size Per/Unit - Min. *** 7.5K
Wire Size (Up to 24 ft.) ** (Circuit 1) No. 10 AWG Copper Conductors)
(Suggested) (Circuit 2) No. 12 AWG Copper Conductors)
Circuit Protection (Circuit 1) 25Amp
Time Delay Fuse or (Circuit 2) 15Amp
HACR Circuit Breaker
Control Voltage 12V DC
Refrigerant R-22
System Refrigerant Charge (Circuit 1 = 46.5) (Circuit 2 = 38.5)
Size (In Inches) Width Height Depth
46 18 22
Installed 205 Pounds
Weight
2.9 SPECIFICATIONS - AIR CONDITIONER
2. 8 WIRING DIAGRAM 39626.501 & 39626.506
**
Models ending with .506 suffix and manufactured with "SIDE AIR DISCHARGE".
For wire lengths over 24 ft. consult the National Electric Code for proper sizing.
The Manufacturer gives only general guidelines for generator requirements. These generator
requirements come from experiences consumers have with our equipment in field applications.
When sizing the generator, the total electrical power must be taken into consideration. Keep in
mind that generators lose power because of altitude increases above sea level , high outdoor
temperatures and lack of maintenance.
*
***

INSTALLATION INSTRUCTIONS
12
3.1 GENERAL INFORMATION
3.1.1 THISUNITISDESIGNEDFOR:
A. Installationinarecreationalvehicleatthetimethe
vehicleismanufactured.
B. Heatingoperationin aMILD GEOGRAPHICAL
AREA where the heat loss is minimal.
C. Turning "OFF" the heat pump and switching to
furnace (aux. heat) when the outside tempera-
tureisbelow30degreesFahrenheit.
D. Returning to heat pump when the temperature
returnsto38degreesFahrenheit.
3.1.2 HEATGAIN/LOSS
Theabilityoftheheatpump/airconditionertomaintain
the desired inside temperature depends on the heat
gain/loss of the RV. Some preventative measures
takenbytheoccupantsoftheRVcanreducetheheat
gainandimprovetheperformanceoftheunit.During
extremelyhighoutdoortemperatures,theheatgainof
thevehiclemay be reduced by:
A. Parking the RV in a shaded area.
B. Usingwindowshade(blindsand/orcurtains)
C. Keepingwindowsanddoorsshutorminimizingus-
age.
C. Avoidingtheuseofheatproducingappliances.
Startingtheunitearlyinthemorningandgivingita
"headstart"ontheexpectedhighoutdoorambient
will greatly improve its ability to maintain the de-
siredindoortemperature.
3.1.3 CONDENSATION:
DometicCorporationwillnotberesponsiblefordam-
agecausedbycondensedmoistureonceilings,walls
or other surfaces. Air contains moisture and this
moisture tends to condense on cold surfaces. When
airenterstheRV,condensedmoisturemayappearon
the ceiling, windows, metal parts, etc.. The unit re-
movesthismoisturefromtheairduringnormalopera-
tion.Keepingdoorsandwindowsclosedwhentheunit
is in operation will minimize condensed moisture on
coldsurfaces.
3.1.4 PRECAUTIONS:
A. Read Installation Instructions carefully before
attempting to start your unit installation.
B. Dometic Corporation will not be liable for any
damagesor injuryincurreddue tofailure inthe
followingoftheseinstructions.
C. Installation must comply with the National Elec-
tric Code ANSI/NFPA-70 and CSA Standard
C22.1 (latest edition) and any State or Local
Codesorregulations.
D. DO NOT add any devices or accessories to the
unit except those specifically authorized by
DometicCorporation.
E. This equipment must be serviced by qualified
personnel andsomestatesrequirethesepeople
to be licensed.
3.0.0 INSTALLATION INSTRUCTIONS
3.2.0 PROCEDURE
3.2.1 LOCATION
Thissystemisintendedforinstallationinarecreationalvehicle
wheretheinteriorisessentiallyoneundividedspace.(SeeFIG.
3.1)
FIG. 3.1
POSSIBLELOCATIONS
A. Theunit is tobeinstalled belowthefloor withDIRECT
access to outside air for the outside coil.
B. Thethermostatcablemaximumlengthistwenty-five(25)
feet.Total lengthofcableused(includingthermostat)
for the control system is seventy-five (75) feet maxi-
mum.
C. Theunitshouldbeprotectedasmuchaspossiblefrom
the elements. Do not locate unit where road spray,
rocks, etc. will hit the unit.
Note:Thefinsoftheoutsidecoilshouldfacetheexterior
ofthevehicle.
3.2.2 OUTSIDECOIL
A. Supply Air
Theinletoftheoutsidecoilshouldbepositionedsothat
itdrawsairfromoutsidethevehicle.Specialcaremust
betaken to preventthedischargeair from recircu-
lating to the inlet of the outside coil. If unit is
installed in a compartment, the discharge air must
be open to the outside. The recirculation of con-
denser air within the compartment will cause high
internaloperationpressuresandtrippingofbreak-
ers will occur. Compartment cannot be sealed.
Shieldsshouldbeaddedtoensurefreshairsupply.See
FIG.3.2
FIG. 3.2
Shields Installed To Prevent
Recirculation Of Outside Air.

13
INSTALLATION INSTRUCTIONS
Wherethereturnairmustbeprovidedthroughlouvers
ormeshscreen,theFREEAREApercentageofthe
materialusedshallbetakenintoconsiderationwhen
making this determination. An example of how to
determineFREEAREAisincludedin"3.2.2.Outside
Coil".
B. Grills (See FIG. 3.4)
Note:Thereturnairgrillmusthavethesamesquare
surface as the return air duct.
1. For each system, there must be a return grill to
bringvehicleairbackintotheunit.Theremustalso
be at least four discharge grills per unit.
2. Returngrillsmustbemountedinfrontoftheinside
coil. If this is not possible, make sure there is
nothing blocking the air flow from the grill to the
inside coil.
3. Theunitmusthaveareturnfilterbetweenthegrill
and the unit. This filter must be accessible for
periodiccleaning.
C. Discharge Air (See FIG. 3.4)
The air diffusion system, supplied by the installer,
must be sized to maintain a static pressure at the
bloweroutletbetween0.40(minimum)and1.20(maxi-
mum)inches watercolumn.
Theinstallerhastheoptionsofsidedischargeortop
discharge and side return. The unit can be ordered
originallywiththeinsideblowermountedtodischarge
theairasrequired.Iftheinstallerneedstochangethe
directionofthedischargeitisnecessarytorotatethe
insideblowerhousing90degrees.
All air handling ducts must be properly insulated to
preventcondensationformingontheirsurfaceduring
operation.Avaporbarriermustalsobesuppliedonthe
outersurfaceoftheinsulationtopreventmoisturefrom
travelingthroughtheinsulationandcondensingonthe
cold duct work.
D. Condensate Drain
A condensate drain tube is located on bottom of the
basepan,underthereturnairopening.
1. Theinstallerneedstoinstallthecondensatedrain
into the base pan and ensure a snug fit.
2. A3"diameterholemustbeprovidedforinstallation
ofthetube and clearance.See Figure 2.11.
Note: Condensate will not drain properly if drain
tube is not installed or missing.
The outside coil is a "draw-through" type. When the
faceofthecoilispositionedbehindalouveredorother
type of restrictive opening, the FREE AREA of the
opening must be at least 648 square inches.
FIG. 3.38
82
2
2
1/2
1/2
1/2
1/2
36
64
EXAMPLE OF HOW TO DETERMINE FREE
AREA OR % OPEN AREA:
TOTALAREA =8 X 8 = 64
FREEAREA = 2 X 2 X 9 openings
=36
%OPENAREA = = 56%
B. Free Area
Free area is the opening that remains in a grill or
louveredpanelaftertherestrictionsaretakenaway.
For example, an opening of 10 x 20 inches has 200
square inches. When this opening is covered with a
grill that is 56 percent open the FREE AREA is (200
x .56), 112 square inches. See FIG. 3.3.
Expandedandperforatedmetalgrillsingeneralvary
from 30 percent to 60 percent open. Be certain that
648squareinchesofFREEAREAisavailabletothe
face of the outside coil.
Note:Serviceaccessmustalwaysbesuppliedeither
as clearance or as a defined access panel.
Donotinstalltheunitwherethefanwilldraw
air from the exhaust of the vehicle, a motor
generator set, transmission, road heat or
any other heat producing source.
CAUTION
3.2.3 MOUNTING
TheModel39626Airconditionerand39726HeatPumpunits
designareforinstallationbelowthefloor.Thisunitshouldbe
mounted in an angle-iron frame, designed and built for the
Model39626and39726.Framerailsshouldnotrestrictthe
condenserairdischargeopening.
Important: Do not mount the Units in a sealed com-
partment.Recirculationofhotcondenserdischargeair
will cause high system pressure and trip breakers.
3.2.4 CLEARANCES
A. Theunitclearancesdependon:
1. Inlet air access used;
2. Dischargeairductarrangement;
3. Returnairduct;
Allowaminimumofeight(8)inchesforthereturnair
duct. Access to the electrical connections must be
providedwhenmakingtheinstallation.
3.2.5 INSIDECOILSECTION
A. Return Air
The inside coil must have free access to room air. A
minimumof135squareinchesofFREEAREA
openingisrequired.
It is the responsibility of the installer to en-
sure that the drain tube is installed properly
and that it will not leak. Dometic Corporation
will not be liable for any structural damage
due to improperly installed, sealed or re-
stricted drain tube.
CAUTION

INSTALLATION INSTRUCTIONS
14
3.3 ELECTRICAL WIRING E. Circuit #2 should be wired through the on-board
generator or a separate power cord dedicated to
Circuit#2.
Note:Astandard30amphookupwillnotpowerboth
Circuit 1 and Circuit 2 and the coach's other major
appliances.
3.3.2 SUPPLYWIRECONNECTION
A. Connect main power supply Cir. #1 to unit electrical
boxwithapprovedRomexconnectors.
B. Using wirenuts attachthemainpowersupplyblack
"Hot" to the units black wire, and white to the white
wire.Attachthemainpowersupplygroundwiretothe
Greenw/yellowwire.
C. Connect the secondary power supply Cir. #2 to unit
electricalboxwithapprovedRomexconnectors.Use
wirenutstoattachblack"Hot"toorangewireofcircuit
#2. and power supply white to the gray wire. Attach
thegroundwireofcircuit#2tothegreenw/yellowwire.
3.4.0 CONTROL SYSTEM WIRING
3.4.1 CONNECTIONOFLOWVOLTAGEWIRES
A. RouteRemoteTemperatureSensorCable,(required
foradditionalunitsorifused),throughthelowvoltage
portontheelectricalboxandattachitthe"white(P4)"
plugonmainboard.
REGISTERREQUIREMENTS
REQ.SIZE MIN.QTY.
4 X 6 8
4 X 8 6
4 X 10 5
4 X 12 4
Condenser air inlet.
Electric box access required.
Circuit #1 - 25 Amp
Circuit #2 - 15Amp
ADDITIONALREQUIREMENTS:
Damper required in furnace.
Vibration isolators should be
used at each mounting point.
12 VDC required for thermostat
operation.
INSULATED DUCT
Minimum Maximum
45IN.280 IN.2
(3 " depth Min.)
FIG. 3.4
Supply Duct must be insulated.
Supply Duct from air conditioner
must be equal to or greater
in IN.2as the floor ductwork.
Use 45 degree angle on inlets
& outlets
Condenser air outlet
(bottom)
Must be isolated from
condenser inlet air.
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 1volt AC
circuit and the polarity is correct. Failure to
do so could result in death, personal injury
or damage to the equipment.
WARNING
!
3.3.1 SUPPLYWIREINSTALLATION
A. Locatetheunitelectricalbox.Removethecoverfrom
the electrical box.
B. Eachelectricalcircuitaregroupedtogetherwithawire
tie. CIR. #1: Black, White and Green w/yellow
CIR.#2:Orange,GrayandGreenw/yellow
C. Route two independent supply circuits of properly
sizedcopperconductorstotheairconditionerelectri-
cal box.
1. Circuit #1 should carry a 25 Amp load.
2. Circuit #2 a 15 Amp load.
D. Circuit #1 should be wired directly from the coach's
mainbreakerpanel.
RETURNSYSTEM
Return to be 6 ft. minimun from floor.
Use wall structure for delivery to basement area.
Return grille must be filtered.
Minimun return required per duct sizing for unit to perform
within Engineer specifications. See Chart below.
MINIMUM MAXIMUM
SIDERETURN 135IN.2291IN.2

15
INSTALLATION INSTRUCTIONS
B. RouteadedicatedDCsupplyline(18-22AWGcopper
conductors) from the Converter or Battery to the
unit's electrical box. Connect with wire nuts positive
(+) DC to the red wire; Negative (-) DC to the black
wire.
C. Routethermostatwiresfromthefurnace(ifapplicable)
to the electrical box and attached them to the blue
wiresextendingfromthemainboard.Thepolarityof
these connections does not matter.
D. Route the Energy Management System 2 wires (if
applicable)totheelectricalboxandconnectthemto
theyellowwiresextendingfromthemainboard.The
polarity of these wires does not matter.
Note:Ifyellowwiresarenotusedandacircuitismade
between them, the unit will fail to operate.
3.4.2 CONTROLCABLEINSTALLATION
A. A 4-conductor flat control cable, must be routed be-
tweentheComfortControlCenter(CCC)andtheelec-
trical box. The maximum length of all control
cables is seventy-five (75) feet.
B. Select the shortest direct route between Comfort
Control Center TM andthe electricalboxfor the sys-
tem.
C. A3/8"diameterholewill beneededtoroutethe con-
trolcablethrough the wall.
D. Leave6" of cableextending throughthewall.
E. The cable that must be used is a 4-conductor flat
control cable.
F. The cable must be terminated with two RJ-11 tele-
phoneconnectors. Referto thecrimp toolmanufac-
turer for crimping instructions. Be sure the cable
is installed correctly into the connector before it is
crimped. Polarity is important and a standard
pre-made telephone cable will not work.
Note: RJ-11 connectors must be wired identically
on both ends. See FIG. 3.5.
4. Avoid locations close to doors that lead outside,
windowsor adjoiningoutsidewalls;
5. Avoid locations close to supply registers and the
airfrom them;
6. Never locate CCC in a room that is warmer or
cooler than the rest of the coach - such as the
kitchen;
7. Themajor livingarea isnormallya goodlocation.
Note: If the system is to be used with a Remote
Temperature Sensor,the ComfortControl Center
may be mounted anywhere that is convenient in
the coach.
8. Tryto avoid hard to reachorhard to see areas.
9. Refertotheinstructionsprovidedwith theRemote
Temperature Sensorfor detailsof installation.
B. Comfort Control Center™ Installation
1. Carefully remove the base plate from the Com-
fortControlCenter™.Thismaybeaccomplished
byinserting a smallscrewdriverunderthetab on
thebottom edgeof thefront coverand gentlypry-
ing. See FIG. 3.6.
G. Plug the communications cable(s) into one of the
telephone jack(s)onthe circuitboard inthe electri-
cal box. (It does not matter which one.)
3.4.3 COMFORTCONTROLCENTER MOUNTING
A. Location
The proper location of the Comfort Control Center
(CCC)isveryimportantto ensurethatitwillprovide a
comfortableRV temperature. Observethefollowing
generalrules when selectingalocation.
1. Locatethe CCCabout54" abovethe floor;
2. InstallCCC on apartition, not onan outside wall;
3. Directheat fromlamps, sunor otherheat produc-
ing items will cause erratic operation and tem-
peratures;
FIG. 3.6
Insert Screwdriver
under Tab
Insert Screwdriver
under Tab
MODE
MODE
FAN FAN
UP UP
DOWN
DOWN
OFFON
OFF ON
ZONE
ZONE
TEMP
TEMP
2. Insert the control cable through the hole in the
base plate and mount the plate to the wall with
thetwo screws provided.Check thealignmentto
ensurelevel installation.
3. Install the control cable RJ-11 connector into the
backof theComfort Control Center™andgen-
tly press onto the base plate.
4. If a Remote Temperature Sensor is to be used,
the connector end must be routed to the electri
calcontrol boxand connectedto thecolor match-
ingplugon the relay board.
5. If a furnace is to be controlled by the system, the
two furnace thermostat leads must be routed to
theelectrical controlof theair conditionerthat will
control it. Make sure at least 15" of the furnace
thermostat wires extend into the electrical con-
trol box.
FIG. 3.5

INSTALLATION INSTRUCTIONS
16
6. If an Energy Management System - EMS (load
shed) is to be used with the control, two wires
must be routed to the electrical control box. The
signalrequiredforthisfunction isa normallyopen
relay contact. When the EMS calls for the com-
pressor to shut off, the relay contacts should
close. Make sure that at least 15" of the EMS
wires extend into the electrical box.
7. In the event that other units are to be installed
(additionalzones),anadditional4-conductorcom-
munications cable must be routed to the other
locations Make sure that at least 15" of the wire
extends into each of the electrical control boxes.
3.5 SYSTEM CONFIGURATION & CHECK
OUT
Now that the system is installed, it is necessary to config-
ure the electronics, and then check all operations. If the
installationis a singlezone, (Without aFurnace) no adjust-
mentto thedip switchesare necessary:however, thestage
dip switch is preset to the "ON" position.
3.5.1 ELECTRONICCONTROLCONFIGURATION
A. If there is more than one zone, the dip switch for
each successive zone must be set to "ON". To gain
access to the dip switches the cover on the unit's
electricalboxmust beremoved.
B. Turn "ON" the "ZONE" dip switch on the electronic
control board to set its zone. See figure 3.7.
NOTE:TheControlBoardshould havetheStageDip
Switch preset to "ON". All other dip switches are
shipped from the factory in the "OFF" position.
C. Turning "ON" of zone 2 dip switch identifies this as
zone 2: likewise zone 3 and 4.
D. Stage dip switch is to be in the "ON" position. This
willcontrolthe operationofthe second compressor,
providedACpower isavailabletoCircuit #2.Thetem-
peraturedifferentialbetweenthefirstandsecondstage
is preset and cannot be changed.
E. Turn "ON" the furnace dip switch when a furnace is
connectedtothe blue wiresoff the control board.
F. Differential dip switch is the difference between the
"ON/OFF" cycle of the thermostat. The normal dif-
ferential is preset in the circuit board with the dip
switchsettothe"OFF" positions.Insomesituations,
it maybenecessary to decreasethe Differential.
The location of the Comfort Control CenterTM may
create a condition where the normal differential will
notmaintain thetemperatureatyourcomfort level.If
thisoccurs,theDifferentialcan beshortenedby plac-
ing the Differential dip switch to the "ON" position.
G. The "GEN START" dip switch - leave in the "OFF"
position.
3.5.2 SYSTEMRESET
Onnewinstallation theCOMFORT CONTROL CENTERTM,
and/or any changes made to the dip switches requires the
electronic control kit to be reset.
A. Turn "ON/OFF" switchtothe "OFF" position.
B. Simultaneously depress and hold the "MODE" and
"ZONE" push-buttons while turning the "ON/ OFF"
switchto "ON".TheLCD Displayshould show "FF"
until the "MODE" and "ZONE" push-buttons are re-
leased.
3.5.3 SystemCheckout
A. Verify that all features of the installed system work.
Check fan speeds, cooling mode, furnace (if con-
nected) and heat pump. If the features do not work,
check all wiring and confirm that the correct options
havebeenselected on theElectronic Control Box.
3.5.4 Service And Disposal Of Unit
A. TheClean Air Act of 1990 setguidelines inregards
to recapturing or disposition of refrigerants. Service
agentsworking withreclamation ofrefrigerants must
becertified by theEnvironmental ProtectionAgency
(EPA).CheckwiththeEPAauthoritiesfor properhan-
dlingor evacuationofrefrigerants.
FIG. 3.7
12 345
HEAT STRIP
ZONE 2
ZONE 3
ZONE 4
FURNACE
ON
678
DIFFERENTIAL
STAGE
GEN START