Nordyne B6BM Series User manual

AIR HANDLER
Please read all information in this manual thoroughly and become familiar with the capabilities
anduseofyourappliancebeforeattemptingtooperateormaintainthisunit.Theseinstructions
are primarily intended to assist qualified individuals experienced in the proper installation of
this appliance. Some local codes require licensed installation/service personnel for this type
ofequipment.Improperinstallation,service,adjustment,ormaintenancemaycauseexplosion,
fire, electrical shock or other hazardous conditions which may result in personal injury or
property damage.
Unless otherwise noted in these instructions, only factory authorized kits or accessories may
be used with this product.Keep this manual where you have easy access to it in the future.If a
problemoccurs,checktheinstructionsandfollowrecommendationsgiven.Ifthesesuggestions
don’t eliminate your problem, call your servicing contractor.
DO NOT DESTROY. PLEASE READ CAREFULLY AND
KEEP IN A SAFE PLACE FOR FUTURE REFERENCE.
IMPORTANT
B6BM, B6EM, & B6VM Series
INSTALLATION INSTRUCTIONS

2
Important Safety Information ....................................3
Requirements & Codes..............................................3
General Information ...................................................4
BeforeYou Install this Unit.........................................4
Locating the Air Handler............................................4
Minimum Clearances.................................................4
Operation of Air Handler During Construction...........4
Installation in a Garage .............................................5
Plenums & Air Ducts .................................................5
Unconditioned Spaces...........................................5
Air Filters................................................................5
Acoustical Duct Work.............................................5
Air Handler Installation..............................................6
Packaging Removal...................................................6
Mounting Applications...............................................6
Upflow Installations ...................................................6
Downflow Installations...............................................6
Horizontal Installations..............................................7
Horizontal Left Installations....................................7
Horizontal Right Installations .................................7
Refrigerant Line Connections....................................8
Orifice removal & Installation .................................8
Connecting the Linsets ..........................................9
Condensate Drainage ............................................10
Electrical Connections.............................................11
Pre-Electrical Checklist ...........................................11
Line Voltage.............................................................11
Grounding................................................................11
Thermostat Connections.........................................11
Control Board..........................................................12
Twinning...............................................................12
Heater Kits...............................................................13
Electronic Air Cleaner..............................................13
Humidifier................................................................13
Optional Humidistat.................................................13
Startup & Adjustments ............................................13
BeforeYou Start the Unit.........................................13
Refrigerant Charging...............................................14
Air Circulation..........................................................14
Running the Blower Continuously........................14
Selecting Continuous Low Spd Fan Operation ....14
Turning the Blower Off..........................................14
System Cooling....................................................14
System Heating....................................................14
Selecting minimum Electric Heat Airflow..............14
Blower Configurations.............................................14
Determining Nominal System Capacity ...............14
3-Speed Units......................................................14
High Efficiency Units (Var. & Fixed Speed)..........15
Selecting Basic Heating Airflow...........................15
Selecting Basic Cooling / Heat Pump Airflow.......15
Dehumidification Options ........................................15
Unit Maintenance......................................................16
Troubleshooting........................................................16
Figures &Tables .......................................................17
Figure 11. B6BM Physical Dimensions................17
Figure 12. Air Handler Components.....................18
Airflow Data.............................................................19
Table 5. B6BM Air Handlers.................................19
Table 6. B6EM Air Handlers.................................20
Table 7. B6EM Air Handlers (Heat Only Airflow)..21
Table 8. B6VM Air Handlers (Cool Only Airflow)..21
Table 9. B6VM Airflow Settings............................22
Electrical Diagrams & Data .....................................23
Figure 13. Single Stage Control Board ................23
Figure 14.Two-Stage Control Board....................23
Figure 15. Fixed Speed Control Board.................24
Figure 16.Variable Speed Control Board.............24
Figure 17. B6BM Wiring Diagram.........................25
Figure 18. B6EM Wiring Diagram.........................26
Figure 19. B6VM Wiring Diagram.........................27
Table 10.B6BM MCA & MOP Data......................28
Table 11.B6(E,V)M & B6BV MCA & MOP Data ..29
Table 12.Control Board Operation.......................30
Installation / Performance Checklist.......................32
TABLE OF CONTENTS

3
IMPORTANT SAFETY INFORMATION
INSTALLER:Pleaseread allinstructionsbeforeservicing
this equipment. Pay attention to all safety warnings and
any other special notes highlighted in the manual.Safety
markings are used frequently throughout this manual to
designateadegreeorlevelofseriousnessandshouldnot
be ignored.WARNING indicates a potentially hazardous
situationthatifnotavoided, couldresultinpersonalinjury
or death. CAUTION indicates a potentially hazardous
situationthatifnotavoided,mayresultinminorormoderate
injury or property damage.
WARNING:
B6 series air handlers leave the factory with
a nitrogen holding charge. Use caution when
preparing coils for field connections.If repairs
makeitnecessaryforevacuationandcharging,
it should only be attempted by qualified,
trained personnel thoroughly familiar with this
equipment.Some local codes require licensed
installation service personnel to service this
type of equipment. Under no circumstances
should the equipment owner attempt to install
and/orservicethisequipment.Failuretocomply
with this warning could result in equipment
damage, personal injury, or death.
NITROGEN
HEALTH
FLAMMABILITY
REACTIVITY
0 Minimal Hazard 1 Slight Hazard
1
0
0
WARNING:
ELECTRICAL SHOCK, FIRE OR EXPLOSION
HAZARD
Failure to follow safety warnings exactly could
result in serious injury or property damage.
Improper servicing could result in dangerous
operation, serious injury, death or property
damage.
• Beforeservicing,disconnectallelectricalpower
to air handler.
• Whenservicingcontrols,labelallwiresprior
to disconnecting. Reconnect wires correctly.
• Verifyproperoperationafterservicing.
REQUIREMENTS & CODES
WARNING:
This unit must be installed in accordance with
instructions outlined in this manual during
the installation, service, and operation of
this unit. Unqualified individuals should not
attempt to interpret these instructions or
install this equipment. Failure to follow safety
recommendations could result in possible
damage to the equipment, serious personal
injury or death.
• The installer must comply with all local codes and
regulations which govern the installation of this type
of equipment. Local codes and regulations take
precedence over any recommendations contained in
these instructions. Consult local building codes for
special installation requirements.
• Thisequipmentcontainsnitrogen gas.Installationor
servicingshould only be performed by qualified trained
personnel thoroughly familiar with this type equipment.
• Allelectricalwiringmustbecompletedinaccordance
with local, state and national codes and regulations
and with the National Electric Code (ANSI/NFPA 70)
or in Canada the Canadian Electric Code Part 1 CSA
C.22.1.
• Installationofequipmentmayrequirebrazingoperations.
Installer must comply with safety codes and wear
appropriate safety equipment (safety glasses, work
gloves,fireextinguisher,etc.) when performing brazing
operations.
• Installthisunitonlyinalocationandpositionasspecied
on pages 4 & 5. This unit is designed only for Indoor
installations and should be located with consideration
of minimizing the length of the supply and return ducts.
SeeTables 5 - 9 (pages 19 - 22) and the rating plate for
proper circulating airflow data.
• Follow all precautions in the literature, on tags, and
on labels provided with the equipment. Read and
thoroughly understand the instructions provided with
the equipment prior to performing the installation and
operational checkout of the equipment.
• This air handler may be used for temporary heating
of buildings or structures under construction. See the
guidelines listed on page 4.
• Airhandlerinstallationsinaresidentialgaragemustbe
installed as specified on page 5.
WARNING:
PROPOSITION 65 WARNING: This product
contains chemicals known to the state of
California to cause cancer, birth defects or
other reproductive harm.

4
GENERAL INFORMATION
Thisappliancehasbeentestedforcapacityandefficiency
in accordance with AHRI Standards and will provide
many years of safe and dependable comfort, providing
it is properly installed and maintained. Abuse, improper
use, and/or improper maintenance can shorten the life
of the appliance and create unsafe hazards.Please read
all instructions before installing the unit.
BeforeYou Install this Unit
√This equipment is securely packaged at the time of
shipmentanduponarrivalshouldbecarefullyinspected
for damage prior to installing the equipment at the job
site.Claimsfordamage(apparentorconcealed)should
be filed immediately with the carrier.
√it is recommended that the cooling load of the area to
be conditioned should be calculated and a system of
the proper capacity selected.
√Checktheelectricalsupplyand verifythe powersupply
isadequateforunitoperation.Thesystemmustbewired
and provided with circuit protection in accordance with
localbuildingcodes.Ifthereisanyquestionconcerning
the power supply, contact the local power company.
√Verify the duct system is appropriate for the air handler
being installed. Please note that when replacing an
existing system with lower air-flow, the duct system
may require modification.
Locating the Air Handler
• Surveythejobsitetodeterminethebestlocationfor
mounting the unit. Consideration should be given to
availabilityofelectricpower,serviceaccess,andnoise.
• Thedimensionsof the room oralcove mustbeable
to accommodate the overall size of the unit and the
installation clearances listed in Table 1. Physical
dimensionsforthisairhandler arealsoshowninFigure
11 (page 17).
• Theairhandlershouldbesetintopositionbeforerouting
the refrigerant tubing.
Minimum Clearances
• This appliance must be installed in accordance with
clearances listed in Table 1. The air handler must be
installed with ample clearance for easy access to the
air filter, blower assembly, heater assembly, controls,
and vent connections. Applicable building codes may
require additional clearance to equipment. Refer to
applicable building codes for details.
• Staticpressuredrop through louveredopeningsand
through return air plenums should be considered in
the overall duct design in the determination of the total
external static pressure.
Table 1. Minimum Unit Clearances
INSTALLATION CLEARANCES
Left Side......... 0 Inches Right Side...... 0 Inches
Back...............0 Inches Front........... †See Notes
†
NOTES:
Alcove Installations - Allow 24 in. minimum clearance
fromfrontofunittonearestwallorpartitionforservicing.
Recommended clearance is 36 in.
REAR
RIGHT
SIDE
LEFT
SIDE
FRONT
Operation of Air Handler During Construction
CAUTION:
Failuretofollowtheseinstructionswillvoidthe
factory warranty and may significantly reduce
the life or the performance of the air handler,
and/or result in other unsafe conditions. It is
the responsibility of the installing contractor
to insure these provisions are met.
Operating an air handler in a construction environment
can cause the appliance a variety of problems. Proper
use of commercial portable space heating equipment
during construction is recommended. This air handler
may be used during construction if it is not in violation of
any applicable codes and the following criteria are met:
• The installation must meet all applicable codes and
be permanently installed according to the instructions
supplied with the air handler including electrical supply
and duct work.
• Theairhandlermustbecontrolledbyaproperlyinstalled
thermostat that complies with the current provisions
of the NEC (ANSI/NFPA 70) and all applicable codes
having jurisdiction. Thermostat connections must be
made in accordance with instructions supplied with the
air handler and thermostat. See pages 11 - 12.
• Theinstallationmustincludeaproperlyinstalledlterin
thereturn air system with no by-passair.Thefilter must
be inspected frequently and replaced when necessary.
• Returnairmustbesuppliedunrestrictedandlocated
such that dust and gases from construction activity are
not introduced into the circulating air system.
• Before occupying the structure: The lter must be
replaced or cleaned, the duct work must be inspected

5
and cleaned of any construction debris, and the air
handler must be cleaned and/or repaired if found to
be dirty, damaged, or malfunctioning in any way by
a qualified HVAC technician. The air handler shall be
inspected and approved by applicable local authority
even if this requires redundant inspections.
• The serial number for the air handler used during
construction must be submitted in writing (fax and
email also acceptable).This information will be used to
track the long-term affects of air handler usage during
construction.Proofofthissubmittalshallbeavailablefor
thefinalinspectionoftheairhandlerpriortooccupancy.
Installation in a Garage
WARNING:
Donotplacecombustiblematerialsonoragainst
the cabinet. Do not place flammable materials,
(gasoline, paint thinners, etc.) or any other
flammable vapors and liquids, in the vicinity
of the air handler.
TheB6Seriesairhandlermaybeinstalledinaresidential
garage with the provision that the unit must be located or
protected to prevent physical damage by vehicles.
as the opening provided on the air handler.The ducts
should be appropriately sized to the capacity of the air
handler to ensure its proper airflow rating.
• Use transition ttings if the supply and/or return air
openings of the unit do not match the duct openings.
Thesetransitionsshouldbedimensionedinaccordance
with standard practice as specified in the ASHRAE
recommendations for duct transitions.
• Flexible connectors may be used between the unit
and the ductwork to prevent transmission of vibration
from the unit to the structure. If electric heater kits are
installed, heat resistant material must be used for the
flexible connector at the supply air end of the unit.
• It is good practice to seal all connections and joints
with industrial grade sealing tape or liquid sealant.
Requirements for sealing ducts vary from region to
region.Consultwithlocalcodesforrequirementsspecific
to your area.
Unconditioned Spaces
All duct work passing through unconditioned space must
beproperlyinsulatedtominimizeductlossesandprevent
condensation.Use insulation with an outer vapor barrier.
Refer to local codes for insulation material requirements.
Air Filters
B6 Series Air Handlers are not supplied with an air filter
whenshippedfromthefactory.Theinstaller must provide
ahighvelocityfilterthatisappropriatelysizedtothereturn
air duct opening or filter rack located in the bottom of the
unit. Accessing the filter does not require tools and can
beremovedfromthefrontoftheunitbyremovingthefilter
door.See Unit Maintenance (page 16) for filter sizes and
installation information.
WARNING:
Never operate the air handler without a filter
or with doors removed. Dust and lint can build
up on internal components,resulting in loss of
efficiency,equipmentdamage,andpossiblefire.
Acoustical Duct Work
• Certain installations may require the use of acoustical
lininginsidethesupply duct work.Acousticalinsulation
must be in accordance with the current revision of the
Sheet Metal and Air Conditioning Contractors National
Association (SMACNA) application standard for duct
liners.DuctliningmustbeULclassifiedbattsorblankets
with a fire hazard classification of FHC-25/50 or less.
• Fiberductworkmaybeusedinplaceofinternalduct
liners if the fiber duct work is in accordance with the
current revision of the SMACNA construction standard
on fibrous glass ducts. Fibrous duct work and internal
acoustical lining must be NFPA Class 1 air ducts when
tested per UL Standard 181 for Class 1 ducts.
• Damping ducts, flexible vibration isolators, or pleated
media-style filters on the return air inlet of the air
Plenums & Air Ducts
• Plenums and air ducts should be installed in
accordance with the standards of the National Fire
Protection Association Standard for Installation of
Air Conditioning Systems (NFPA 90A), Standard for
Installation of Residence Type Warm Air Heating
and Air Conditioning Systems (NFPA 90B), and all
applicablelocalcodes.NFPApublicationsare available
by writing to: National Fire Protection Association,
Batterymarch Park, Quincy, ME 02269 or visit
www.NFPA.org online.
WARNING:
All return ducts must be secured to the air
handler using appropriate methods. All return
ducts must be adequately sealed.When return
air is provided through the bottom of the unit,
the joint between the air handler and the return
air plenum must be air tight.
Returnairand circulatingairducts mustnotbe
connected to any other heat producing device
such as a fireplace insert, stove, etc.This may
result in fire, explosion, carbon monoxide
poisoning,personalinjury,orpropertydamage.
• Designtheductworkaccordingtomethodsdescribed
bytheAirConditioningContractorsofAmerica(ACCA).
• Thisunitisdesignedonlyforusewithareturnandsupply
duct.The return air duct must have the same free area

6
AIR HANDLER INSTALLATION
The B6 Series Air Handler is shipped ready for vertical
upflow installation and is approved for attic, basement,
alcove/closetorcrawlspaceinstallationwithzeroclearance
to combustibles. See Table 1 (page 4) for required
installationclearances.Thisapplianceisapprovedonly
for indoor use.
• Theunitmustbeleveledatinstallationandattachedto
a properly installed duct system.
• Thesurfacethattheairhandlerismountedonmust
provide sound physical support of the unit.
• Theairhandlermustbeinstalledsothatallelectrical
components are protected from water.
• Ifalouvereddoorisinstalledacrossthefrontofthis
unit, the appliance must be mounted flush or behind
front edge of finished wall.
• Always reinstall the doors on the air handler after
servicingorcleaning/changingthefilters.Donotoperate
theairhandlerwithoutalldoorsandcoversinplace.
Packaging Removal
Remove the shipping crate and User’s Manual from the
equipment.When removing the crate, use extra care so
tubing connectios are not damaged. Do not pull on the
coils upper tubes.
Mounting Applications
Vertical only air handlers are factory ready for upflow
applications. These units may be applied in downflow
applications when applied with the appropriate field kit.
Factory ready horizontal air handlers may be applied in
upfloworhorizontal-leftand-rightdischargeapplications.
These units may also be applied in downflow discharge
when applied with the appropriate field kit as specified in
the units Technical Specifications.
Through-the-floor installations require a 1/4” thick
noncombustible resilient gaskettobe used whenever the
supplyorreturnairductspassthroughthefloor.Thegasket
should be positioned between the duct, unit, and floor.
Upflow Installations
All air handlers are factory shipped, ready for upflow
installation. The horizontal drain pan may be removed
from the air handler when installing the unit in an upflow
configuration.All return air must enter from the bottom of
the unit. A typical upflow unit is shown in Figure 1.
Downflow Installations
Thedownflowaccessorykit(SeeTechnicalSpecifications)
is required for downflow applications. Instructions for
installingthedownflowaccessorykitareincludedwiththe
kit.Itisrecommendedthattheaccessorybeinstalledprior
toinstallingtheunit.Allreturnairindownflowapplications
mustenterthroughthetopoftheunit.Atypicalinstallation
of the unit in a downflow application is shown in Figure 2.
Figure 1. Upflow Installation
Horizontal
Drain Pan
Return
Air
Figure 2. Downflow Installation
Tube
Close-off
Plate
Coil
Cabinet
Adaptor Kit
handler may be used to reduce the transmission of
equipment noise eminating from the air handler.These
treatmentscanproduceaquieterinstallation,particularly
in the heated space. However, they can increase the
pressure drop in the duct system. Care must be taken
to maintain the proper maximum pressure rise across
the air handler, temperature rise and flow rate. This
maymeanincreasingthe duct sizeand/orreducingthe
blower speed.These treatments must be constructed
and installed in accordance with NFPA and SMACNA
construction standards. Consult with local codes for
special requirements.For best sound performance, be
sure to install all the needed gaskets and grommets
around penetrations into the air handler, such as for
electrical wiring.

7
Figure 4. Unit Horizontally Suspended
Threaded
Rod
Lag
Bolt
Nuts (x2)
Washer
and
Lockwasher
Nuts (x2)
Horizontal Installations
The B6 Series air handler can be installed horizontally in
an attic, basement, crawl space or alcove. It can also be
suspended from a ceiling in a basement or utility room in
either a right to left airflow or left to right airflow as shown
in Figure 3.Air handlers may or may not be shipped from
the factory with all the parts required for horizontal left
applications and horizontal right applications.If your unit
does not have parts for a horizontal application, a kit may
be available.
NOTE: In all horizontal applications in which the unit is
installed above a finished ceiling and/or living space, a
secondarydrainpanmustbeinstalledundertheentireunit
to avoid damage to the ceiling in the event of condensate
overflow.Additionally,itisrecommendedthatanapproved
water level indicator or float switch device be used to
shut down the unit in the event water is detected in the
auxiliary drain pan.
If suspending the air handler from the ceiling, assemble
asupport frame (Figure 4) using slottediron channel and
full threaded rod. Fasten the frame together with nuts,
washers, and lockwashers. Secure the support frame
to the rafters with lag bolts.The air handler can also be
suspended using steel straps around each end of the
unit.Thestraps should be attachedtotheairhandlerwith
sheet metal screws and to the rafters with bolts.
Horizontal Left Installations:
1.Remove the coil access door.
2.Remove the plug from one of the threaded holes in the
horizontal drain pan. Completely remove the webbing
located in the threaded holes of the horizontal drain
pan. IMPORTANT: If the webbing is not removed, the
condensate will not drain properly and ceiling damage
may occur.
3.Insertthe plug(fromhorizontaldrainpan) intotheopen
and unused drain hole in the drain pan at the bottom
of the unit to block bypass air.
4.Remove the corresponding drain line knockout from
the coil access door to allow access to the horizontal
drain.
5.Replace the door and attach the drain line.
Horizontal Right Installations:
1.Removethecoilaccessdoor.Unscrewtheline-settube
close-off plate from the front left cabinet rail.
2.Slide the coil and drain pan assembly out of the unit.
3.Remove the sheet metal hairpin covers (if supplied)
from the back of the coil and discard.
4.Place the horizontal drain pan on the opposite side of
the coil.On units with 2 sets of knockouts, remove the
other set of knockouts in the coil spacing plates and
insert support rod.
5.Slide the coil and the horizontal drain pan assembly
back into the unit.Re-attach the tube close off plate.
NOTE: For A-size cabinet applications, it may be
preferrable to remove the blower assembly prior
to installing the coil & drainpan. In this case follow
instructions 1-4 as listed above but also remove the
blower access door and blower assembly. The blower
assembly is secured with two screws on either side
nearthefront.Withtheseremovedtheblowerassembly
can slide out of the front of the unit.Install the coil and
drain pan as described in step 5 and then replace the
blower assembly.Take care to ensure that the flanges
on the sides of the blower assembly are captured by
the pockets in the blower deck.It may be necessary to
lift the blower assembly during insertion to allow the
lower blower leg to clear the side of the drain pan.The
blower will stop against the back of the blower deck.
Replace the two screws and the blower access door
and procede with steps 6-9.
6.Remove the plug from one of the threaded holes
in the horizontal drain pan. Completely remove the
webbing located in the threaded holes of the drain
pan. IMPORTANT: If the webbing is not removed,
the condensate will not drain properly and ceiling
damage may occur.
Figure 3. Horizontal Configurations
HORIZONTAL RIGHT
HORIZONTAL LEFT
RETURN
AIR
RETURN
AIR

8
Orifice Removal & Installation
The orifice installed in the air handler has been sized for
use with the most popularly matched outdoor units.The
orifice size as shipped from the factory is listed on the air
handler rating plate. Perform steps 1 - 9 to confirm that
the orifice size meets the requirements outlined in the
outdoor unit installation manual.
1.Remove the cap from the end of the liquid line.
2.Verifypressurization bydepressing the Schrader valve
ontheendoftheliquidline.Listenforanyescapinggas.
If there is no pressure, test the coil for leakage.
• Ifleakageisfound,clearlymarkthelocationoftheleak
and return the coil to the distributor for processing.
• Ifnoleaksarefound,thecoilmaybeinstalled.
3.Depress the valve to relieve all pressure from the coil.
4.Remove and discard the valve core.
CAUTION:
To prevent damage to the unit or internal
components, it is recommended that two
wrenchesbeusedwhenlooseningortightening
nuts. Do not over tighten!
5.Usingtwowrenches,loosenthenutanddistributorbody
as shown in Figure 5.Turn the assembly nut counter-
clock-wise until the orifice body halves are seperated.
Refrigerant Line Connections
WARNING:
Thecoilintheairhandlerisfactoryshippedwith
a nitrogen charge. Avoid direct face exposure
or contact with valve when gas is escaping.
Always ensure adequate ventilation is present
during the depressurization process.Address
any uncertainties before proceeding. Failure
to comply with this warning could result in
equipment damage, personal injury, or death.
NITROGEN
HEALTH
FLAMMABILITY
REACTIVITY
0 Minimal Hazard 1 Slight Hazard
1
0
0
• Theinstaller shouldmakeevery effortto ensurethe
field installed refrigerant containing components of the
system have been installed in accordance with these
instructions andsoundinstallation practicesforreliable
system operation and longevity.
• Theairhandlercoildoesnotcontainarefrigerantcharge.
Refer to the installation instructions supplied with the
outdoor unit for refrigerant charge information.
• Alwaysrefertotheinstallationinstructionssuppliedwith
the outdoor unit for piping requirements. The suction
and liquid lines must be sized in accordance with the
condensing unit specifications. See Figure 11 (page
17) for liquid and suction line locations.
• When connecting refrigerant linesets together, it is
recommended that dry nitrogen be flowing through the
jointsduringbrazing.Thiswillpreventinternaloxidation
and scaling from occurring.
• Refrigeranttubingshouldberoutedinamannerthat
minimizesthelengthoftubingandthenumberofbends
in the tubing. It should be supported in a manner that
prevents it from vibrating or abrading during system
operation.Tubingshouldbekeptcleanofforeigndebris
during installation.
• Ifpreciseformingofrefrigerantlinesisrequired,acopper
tubingbenderisrecommended.Avoidsharpbendsand
contact of the refrigerant lines with metal surfaces.
Figure 5. Loosening of Nut & Distributor Body
6.Insert a light-gauge wire hook between the distributor
body and the restrictor orifice while being careful not
to scratch either part. Carefully remove the restrictor
orifice from the distributor body.See Figure 6 (page 9).
7.Check the actual size of the new orifice. NOTE: The
size is stamped on its side. Do not use pin gauges to
measure the orifice diameter.
8.Insert the new orifice into the distributor body, rounded
end down.See Figure 7 (page 9).
NOTE: It is recommended that the suction line be
insulated up to the coil inside of the cabinet.
7.Inserttheplug(fromhorizontaldrainpan)intotheopen
and unused drain hole in the drain pan at the bottom
of the unit to block bypass air.
8.Remove the corresponding drain line knockout from
the coil access door to allow access to the horizontal
drain.
9.Replace the door and attach the drain line
• Refrigerant lines should be wrapped with pressure
sensitive neoprene or other suitable material where
they pass against sharp sheet metal edges.
• B6 Series air handlers are charged through service
valves on the end of the liquid tube for each circuit.
These must be removed before brazing the line sets.

9
Connecting the Linesets
IMPORTANT NOTES FOR HORIZONTAL OR
DOWNFLOW INSTALLATIONS WITHTXVVALVE:
• The sensing bulb must be located flush against the
suction line for optimum heat transfer.
• Avoidattachingthesensingbulbtothelowestpartof
thesuctionlinewherecondensatemayaccumulate.
• Do not locate the sensing bulb on vertical sections
of the lineset.
• For horizontal lines,the bulb should not be located
at 12 or 6 o’clock position of the suction line.The
best location is at 4 or 8 o’clock.
• For additional information on proper sensing bulb
locations, please refer to the valve manufacturer’s
instructions.
IMPORTANT:ThestepsintheOrificeRemoval&Installation
section (page 8) must be performed before the linesets
are connected.
1.Remove grommets from line set holes.
CAUTION:
It is recommended that a wet rag be wrapped
around the suction line in front of the close
off plate or the sensing bulb (if TXV is
installed) before applying heat. Failure to keep
components cool during brazing may result
in structural damage, premature equipment
failure, or possible personal injury.
2.Unbraze and remove the cap on the suction line.
3.Route and cut both lineset tubes to proper length in
accordance with the outdoor unit specifications.Verify
the ends are round, clean, and free of any burrs.
4.Positiongrommetonlinesetwithsufficientdistanceaway
frombrazingarea.Brazingprocessescanpermanently
damage grommets.
5.Connect the suction and liquid lineset tubes.
CAUTION:
It is recommended that a wet rag be wrapped
around the suction line in front of the close
off plate or the sensing bulb (if TXV is
installed) before applying heat. Failure to keep
components cool during brazing may result
in structural damage, premature equipment
failure, or possible personal injury.
6.Braze the individual connections with dry nitrogen
flowing through the joints. NOTE: This will prevent
internal oxidation and scaling from occurring.
Figure 7. Restrictor Insertion into Distributor Body
Figure 6. Removal of Orifice
CAUTION:
To prevent damage to the unit or internal
components, it is recommended that two
wrenchesbeusedwhenlooseningortightening
nuts. Do not over tighten!
9.Realign the assembly nut on the distributor body and
hand tighten both components. Mark a line on both
bodiesandthentightenanadditional1/4turnusingtwo
wrenches.Themovementofthetwolineswillshowhow
much the nut is tightened. If a torque wrench is used,
tighten to 10-12 ft. lbs. or 14-16 Nm.

10
• Iftheairhandlerislocatedinorabovealivingspace
where damage may result from condensate overflow,
an auxiliary drain pan shall be installed under the unit.
A separate drain line should extend from the pan to a
conspicuous point and serve as an alarm indicating
that the primary drain is restricted.As an alternative to
a separate drain line, an approved water level indicator
or float switch device may be used to shut down the
unit in the event water is detected in the auxiliary pan.
• Installasingle5inchtrapinthecondensatedrainline
as close to the coil as possible. Make sure that the
top of the trap is below the bottom of the drain pan to
preventthecondensatefromoverflowingthedrainpan.
NOTE: There must be only one trap in the drain line.
Using more than one trap may prevent drainage.
• Primethetrapwithwater.Insulatethedrainifitislocated
inanunconditionedspace,andtestthecondensateline
for leaks.Consult local codes for additional restrictions
or precautions.
• During system checkout, inspect the drain line and
connections to verify proper condensate drainage.
7.Wrap the refrigerant lines with pressure sensitive
neoprene or other suitable material especially where
the lines enter the opening in the sheet metal.
8.Evacuatethesystemofmoistureandnon-condensables
to prevent low efficiency operation or damage to the
unit. The suggested range of evacuation is 350 - 500
microns.
9.Charge the system with refrigerant. Refer to the
outdoor unit installation manual for additional charging
instructions.
10.Check the system for leaks, including the lineset and
the brazed joints.
11.Replace all grommets and properly dispose of all
removed parts.
Condensate Drainage
CAUTION:
The air handler must be level to ensure proper
condensate drainage. An unlevel installation
may result in structural damage, premature
equipment failure, or possible personal injury.
• Methodsfordisposingofcondensatevaryaccording
to local codes.Refer to local codes or authority having
jurisidiction for restrictions and proper condensate
disposal requirements.
• The drain pan that is supplied with this air handler
contains a primary and secondary drain fitting. The
condensate is drained from the unit through two 3/4”
female pipe fittings located on the front side of the unit
as shown in Figure 8.
• Thedrainpanmustbedrainedwitheldsuppliedtubing
or pvc pipe and adequately trapped. Both drain tubes
must have a minimum diameter of 3/4”and be trapped
separately.
IMPORTANT: Failure to install a trap may result in
condensation overflowing the drain pan, resulting in
substantial water damage to surrounding area.
• Routebothlinestoasuitabledrain,avoidingsharpbends
and pinching of the lines.The drain should maintain a
minimum horizontal slope in the direction of discharge
of not less than 1” vertical for every 10 ft of horizontal
run.
3/4” Adapter w/
3/4” dia. hose barb
3/4” minimum dia.
PVC or flexible tubing
HORIZONTAL
UPFLOW
DOWNFLOW
NOTES:
1.The drain lines must maintain a downward slope to ensure proper
condensate drainage.
2. Each condensate drain must be trapped separately using a J-Trap or
field supplied loop.
Figure 8. Condensate Drainage Example

11
ELECTRICAL CONNECTIONS
WARNING:
ELECTRICAL SHOCK, FIRE OR EXPLOSION
HAZARD
Failure to follow safety warnings exactly could
result in serious injury or property damage.
Improper servicing could result in dangerous
operation, serious injury, death or property
damage.
• Beforeservicing,disconnectallelectricalpower
to the air handler.
• Whenservicingcontrols,labelallwiresprior
to disconnecting. Reconnect wires correctly.
• Verifyproperoperationafterservicing.
• Electrical connections must be in compliance with
all applicable local codes and ordinances, and with
the current revision of the National Electric Code
(ANSI/NFPA 70).
• ForCanadianinstallations,theelectricalconnections
and grounding shall comply with the current Canadian
Electrical Code (CSA C22.1 and/or local codes).
Pre-Electrical Checklist:
√Verify the voltage, frequency, and phase of the supply
sourcematchthespecificationsontheunitratingplate.
√Verifythat the serviceprovidedbytheutilityissufficient
tohandletheadditionalloadimposedbythisequipment.
Seethe unitwiring labelorTables9 -10(pages28 -29)
for proper high and low voltage wiring.
√Verifyfactorywiringisinaccordancewiththeunitwiring
diagram(Figures17-19,pages24-26).Makesure the
connectionsdidn’tloosenduringshippingorinstallation.
LineVoltage
• Anelectricaldisconnectmustbelocatedwithinsight
ofandreadilyaccessibletotheunit.Thisswitchshall
becapableofelectricallyde-energizingtheoutdoorunit.
Seeunit data labelforproperincoming field wiring.Any
other wiring methods must be acceptable to authority
having jurisdiction.
• Itisrecommendedthatthelinevoltagetotheunitbe
supplied from a dedicated branch circuit containing the
correct fuse or circuit breaker for the unit.
• Overcurrentprotectionmustbeprovidedatthebranch
circuitdistributionpanel and sizedas shownonthe unit
ratinglabelandaccordingtoapplicablelocalcodes.See
the unit rating plate andTables 7 - 8 (pages 27 - 28) for
maximum circuit ampacity and maximum overcurrent
protection limits.
• The installer should become familiar with the wiring
diagram/schematic before making any electrical
connections to the unit. See the unit wiring label or
Figures 9 & 17 - 19 (pages 12 & 24 - 26).
• Useonlycopperwireforthelinevoltagepowersupply
to this unit.Use proper code agency listed conduit and
a conduit connector for connecting the supply wires to
the unit.Aluminum supply wire may be used if a heater
kit is installed.
• Ifreplacinganyoftheoriginalwiressuppliedwiththe
unit,thereplacementwiremustbecopperwireconsisting
of the same gauge and temperature rating.
• Providepowersupplyfortheunitinaccordancewiththe
unit wiring diagram, and the unit rating plate. Use UL
listedconduitandconduitconnectorsforconnectingthe
supply wires to the unit and for proper grounding.Field
supplied bushings for the power supply cables must be
added to support and protect the power supply cables.
• All208/230Voltunitsareshippedfromthefactorywired
for 240 volt operation.For 208V operation, remove the
lead from the transformer terminal marked 240V and
connect it to the terminal marked 208V.
Grounding
WARNING:
The unit cabinet must have an uninterrupted
or unbroken electrical ground to minimize
personalinjuryifanelectricalfaultshouldoccur.
Do not use gas piping as an electrical ground!
This unit must be electrically grounded in accordance
with local codes or, in the absence of local codes, with
the National Electrical Code (ANSI/NFPA 70) or the CSA
C22.1 Electrical Code.Use the grounding lug provided in
the control box for grounding the unit.
Thermostat Connections
• Thermostatconnectionsshall bein accordance with
the instructions supplied with the thermostat. The
thermostat used with this equipment must operate in
conjunction with any installed accessories.Typical AC
and air handler hookups are shown in Figure 9 (page
12).
CAUTION:
Isolation must be maintained from the external
Class 2 output of any transformer in a cooling
circuit.Useathermostatwithisolatingcontacts
to prevent inter-connection of Class 2 outputs.
• Wherelocalcodesrequirethatthethermostatwiring
must be routed through a conduit or raceway, splices
can be made inside the unit; however, all wiring must
be NEC Class 1 and separated from incoming power
leads.
• Thethermostatshouldbemountedabout5feetabove
theflooronaninsidewall.DONOTinstallthethermostat
on an outside wall or any other location where its
operationmaybeadverselyaffectedbyradiantheatfrom

12
fireplaces, sunlight, or lighting fixtures, and convective
heat from warm air registers or electrical appliances.
Refertothethermostatmanufacturer’sinstructionsheet
for detailed mounting and installation information.
• Installthegrommet,whichispackedwiththeunit,in
the hole for low-voltage wires. Properly connect the
low-voltage wiring between the thermostat, outdoor
unit, and control board. NOTE: When the low voltage
wires are positioned in this grommet, the grommet will
preventchafingand/orshortingofthelowvoltageleads.
Control Board
The control board in the air handler controls the timing
sequenceoftheelements.Theboardisequippedwitha3
secondbloweron delayand a 15 second bloweroffdelay
in heating and a 40 second blower off delay in cooling.
See Figures 13 or 14 (page23) and Table 12 (pages 29-
30) for control board modes and actions.
Twinning
B6BMairhandlersarenotsuppliedwithabuiltintwinning
capability. To connect two air handlers to a common
singlestageACcondensingunitorheatpump,atwinning
kit is available for field installation. Please follow the
instructions supplied with the kit.
Figure 9.TypicalThermostat Connections
GRCW/EO Y
Thermostat
GR
W
Thermostat
Y
C
Y
GR
W
Thermostat
Y
C
Air
Handler
Air
Conditioner
Y
Typical Air Conditioner with
Standard Air Handler
GRCE
OY
Thermostat
Typical Heat Pump with
Standard Air Handler
Typical Air Conditioner with
Variable Speed Air Handler
Typical Heat Pump with
Variable Speed Air Handler
GR
W2 C
O
Y1
Thermostat
O
Y1
R
C
GR
W/E
Thermostat
Y1
C
Y1
W2
Typical 2-Stage Air Conditioner
withVariable Speed Air Handler
Typical 2-Stage Heat Pump with
Variable Speed Air Handler
Y2
Y2
Y2
Y2 OUT
W/E
R
Air
Conditioner
Air
Handler
Air
Conditioner
Air
Handler
Heat Pump
Air
Handler
Heat Pump
O
R
C
Y
Air
Handler
Heat Pump
NOTE: Jumper between
W2 & E is required when
no OD T-Stat is used.
W1
Y
G
R
C
NOTE: Jumper W1 & W2
together if not using W2
on thermostat
Y1
W2
W1
O
Y/Y2
G
R
C
Y1
W2
W1
O
Y/Y2
G
R
C
W2
Air
Handler
W1
Y
G
R
C
R
C
Y
W2
O
Y1
W2
W1
O
Y/Y2
G
R
C
Y1
W2
W1
O
Y/Y2
G
R
C
W2
W2
W2
NOTE: Jumper W1 & W2
together if not using W2
on thermostat

13
NOTE: Variable speed air handlers cannot be twinned.
Heater Kits
When electric heat packages with circuit breakers are
field-installed, the circuit breaker may be used as a
disconnecting means in most applications. Reference
the NEC and local codes for disconnect requirements.
If a heater kit is installed:
The B6BM air handler is shipped from the factory without
an electric heater kit installed. If Electric heat is desired,
the H6HK heater kit may be purchased separately and
fieldinstalled.Determinethecorrectsizeheaterkitforyour
unit by referring to the list below or the units rating label.
A Cabinet.......................................................15Kw max
B Cabinet.......................................................20Kw max
C Cabinet.......................................................30Kw max
1.Connect the 2 wire plug of the air handler to the mating
2 wire plug of the heater kit.
2.Connect the line voltage leads to the circuit breaker or
terminal block provided.
3.Connect the heater kit plug with the mating receptacle
on the air handler control board.
If a heater kit is not installed:
1.Removethe2wire plug of the air handler bycutting the
wires and discarding the plug.
2.Strip the ends of the 2 air handler wires and connect
to the line-voltage leads with the 2 wire nuts provided.
Electronic Air Cleaner (EAC)
The unit has an output to power an electronic air cleaner
when the blower is running. This output is rated to 1.0
amp at 208/240V.
Humidifier
The unit has an output to power a humidifier when the
blower is running. This output is rated to 1.0 amp at
208/240V.
Optional Humidistat
(B6EM or B6VM Models Only)
The optional humidistat may be installed in the return air
duct to provide excellent humidity control when needed
andmaximumsystemcapacityandenergyefficiencywhen
humidity levels are normal.The humidistat senses when
humidity in the return air stream is above a preset level
(fieldadjustable)andsendsasignaltothemotortoreduce
theairflowsothatmoremoisturemayberemoveduntilthe
humidity level drops.The air handler is pre-programmed
for humidistat operation.
Install the humidistat in the return air duct as directed in
the installation instructions included with the kit.Wire the
humidistat through the low-voltage wire entrance in the
airhandler to thecontrolboard terminalmarkedDEHUM.
Wirethehumidistattoopenonriseinhumidity.SeeFigures
15 & 16 (page 23).
STARTUP & ADJUSTMENTS
WARNING:
Theevaporatorcoilis shipped fromthefactory
with a nitrogen charge. Use caution when
preparing coils for field connections.If repairs
makeitnecessaryforevacuationandcharging,
it should only be attempted by qualified,
trained personnel thoroughly familiar with this
equipment.Some local codes require licensed
installation service personnel to service this
type of equipment. Under no circumstances
should the equipment owner attempt to install
and/orservicethisequipment.Failuretocomply
with this warning could result in equipment
damage, personal injury, or death.
NITROGEN
HEALTH
FLAMMABILITY
REACTIVITY
0 Minimal Hazard 1 Slight Hazard
1
0
0
BeforeYou Start the Unit
Prior to start-up, complete the following inspections:
√Verifytheunitislevelandproperlylocatedwithadequate
clearances for servicing the unit.SeeTable 1 (page 4).
√Check condensate drain line(s) for proper drainage.
√Verify the surrounding area and top of the unit is free
from obstructions and debris.
√Check all duct connections. Make sure the duct work
is adequately sealed to prevent air leakage.
√Check all coil connections for leaks.
√Verify that the line voltage power leads are securely
connectedandtheunitisproperlygrounded.Makesure
alldoorsare installed beforerestoring powerto the unit
√Verify the thermostat is wired correctly. Make sure all
low voltage wires are securely connected.
√Verify the power supply branch circuit overcurrent
protection is sized properly.
√Verify filter is properly and securely installed.
IMPORTANT: Before starting the unit, install the initial
charge on units that are factory shipped with a nitrogen
holding charge:
1.Read all installation instructions first.
2.Purge the nitrogen holding charge.
3.Evacuate the unit to 350 - 500 microns.
4.Allow the unit to remain under vacuum for at least 30
minutes.

14
Blower Configurations
Determining Nominal System Capacity
To select the appropriate airflows for the air handler, the
nominal system capacity must be known. The nominal
system capacity is always the nominal capacity of the
outdoor unit. However, in some situations the nominal
system capacity may not be the same as the nominal
capacity of the air handler. Always refer to the nominal
capacity of the outdoor unit to determine the nominal
system capacity.
NOTE: The CFM values listed in Table 9 (page 22) are
not dependent on duct static pressure.The VSHE motor
automatically compensates for changes in duct static
pressure (within the limits of the motor).
3-Speed Units
The blower speed is preset at the factory for operation
at the same speed for heating and cooling, by using the
jumping terminal on the blower motor and connecting it
to the desired speed with both the red and black wires
connected to the jumping terminal. NOTE: The control
board is programmed with a 40 second off delay in the
cooling mode for optimum system performance and
efficiency.
CAUTION:
To avoid personal injury or property damage,
make sure the motor leads do not come into
contactwithanyuninsulatedmetalcomponents
of the unit.
For optimum system performance and comfort, it may be
necessary to change the factory set speed. See Table 5
(page 19) for airflow data.To change the blower speed:
1.Disconnect all electrical power to the unit and remove
the upper door.
2.Remove the black and red wires from the blower motor
jumping terminal. Discard the blower motor jumping
terminal.
3.Connect the heating speed wire (red) and the cooling
speedwire(black) tothedesiredblowerspeed marked
on the terminal block of the blower motor.
5.Weigh in the proper amount of new (or reclaimed)
refrigerant. Refer to the air conditioner or heat pump
installation manual for the proper type and quantity of
refrigerant.
Refrigerant Charging
The system refrigerant charge can be checked and
adjusted through the service ports provided at the front
paneloftheoutdoorunit.Useonlygaugelineswhichhave
aSchraderdepressiondevicepresenttoactuatethevalve.
Air Circulation
Running the Blower Continuously
Set the thermostat’s system mode to OFF and the
thermostat’s fan mode to ON. The blower motor should
run continuously.Check for air delivery at the register(s).
Ensure that there are no obstructions at the registers or
in the ducts.
Selecting continuous low speed fan operation
(Standard Blower)
The air handler is equipped with an option of continuous
low speed fan operation.When Gis energized without Y/
Y2, the air handler will operate using the cooling speed.
With G& Y/Y2 or Y/Y2 energized, the air handler will
operate in the selected cooling speed (including 40 sec
blower-off delay).
Turning the Blower Off
Set thermostat’s fan mode to AUTO, the blower will shut
down immediately.
System Cooling
1. Set the thermostat’s system mode to COOL and fan
mode to AUTO. Lower the thermostat’s temperature
mode below room temperature and observe that the
blower energizes. Check the air being discharged at
the register is cooler than room temperature. Verify
unit refrigerant pressures are in order. Blower should
be turning in direction indicated by arrow.
NOTE: DONOTalterunitwiring.Listenforanyunusual
noises.Locate the source and correct as needed.
2. Allow the unit to run for several minutes and then set
thethermostat’stemperatureaboveroomtemperature.
Verify the blower cycles off with the thermostat.
System Heating
1.Setthethermostat’ssystemmode toHEAT andthefan
mode to AUTO.Increase the thermostat’s temperature
above room temperature and observe that the blower
energizes.Checktheairbeingdischargedattheregister
is warmer than room temperature.
2. Allow the unit to run for several minutes and then set
thethermostat’stemperaturebelowroomtemperature.
Verify the blower cycles off with the thermostat.
Selecting Minimum Electric Heat Airflow
The minimum electric heat airflow setting controls the
minimum air flow that will be produced whenever electric
heater kits are used. When the electric heater kit is
energizedalongwithaheatpump,theairflowmaybehigher
dependingonthebasiccooling/heat-pumpairflowsetting.
The minimum electric heat airflow is selected by the red
blower wire on 3-speed models or setting switches 1,2,3
&4onB6EMmodels.B6VMmodelsautomaticallysetthe
heatingspeedbasedontheamountofinstalledheat.The
A/B switch must be set appropriately for the unit cabinet
size. For C-sized cabinets, the A/B switch can be set in
either position.The remaining 3 HEAT switches have no
function.SwitchsettingsarelistedinTables6or9(pages
20& 22).NOTE: ForB6EM Models,the minimumelectric
heat airflow setting may be set higher, but must never be
set lower than the setting shown in Table 7 (page 21).

15
• Terminal4=Hispeed
• Terminal5=Medspeed
• Terminal6=Lowspeed
4.Replace the upper door and secure it to the unit.
5.Restore power to the unit.
High Efficiency Units (Variable & Fixed Speed)
IMPORTANT! This air handler has been designed to
give the installer maximum flexibility to optimize system
performance, efficiency, and comfort. Because there
are so many different ways to set up the air handler it is
important to read and follow these directions carefully.
B6EM&B6VMairhandlersusehighefficiencycirculating
air motors that come in two variations and both are
controlleddifferently.Thefixedspeedmotorcontrolboard
(Figure 15, page 23) controls the torque and the variable
speedmotorcontrolboard(Figure16)controlstheairflowat
aconstantCFM.Bothboardsusethesamecontrolboard.
Before operation, the air handler must be configured to
matchtheunitwiththesystem,systemoptions,andclimatic
conditions. When configured, the air handler responds
directly to the thermostat inputs, as well as the optional
humidistat (see page 13). During normal operation, the
motor will gradually change speeds during start-up, shut
down,whenthermostatinputschange,andwhentheduct
static pressure changes (vents closed or opened, filter
clogging, etc.). The air handler is configured by setting
the selector switches and removing jumper connectors.
Selecting Basic Heating Airflow
Fixed & variable speed motor control boards (Figures
15 & 16) contain a set of dip switches for setting the
blower speed.For B6EM models, pins 1-4 set the speed
for heating. For B6VM models, the A/B switch must be
set for the appropriate cabinet size (either setting can be
used for C-size cabinets).The airflow is set automatically
based on the amount of installed heat.For both B6EM &
B6VMmodels,thecoolingspeed isselectedviaswitches
5,6,7,&8.Todeterminetheappropriateswitchsettingsfor
your installation, seeTables 6, 7, 8, or 9 (pages 20 - 22).
Selecting Basic Cooling / Heat Pump Airflow
Thebasiccooling/heat-pumpairflowiscontrolledbysetting
switches5-8onthemotorcontrolboard(mountedonthe
blower).All airflows for other modes of operation (except
electric heat) are determined by this basic setting. FAN
ONLY would deliver 50% of the selected cooling airflow.
Table 8 (page 20) lists the basic airflow values versus the
airflowselectorswitchsettingsandrangesofbasicairflow
settingsrecommendedforeachnominalsystemcapacity.
• When operating in the heat pump mode, a higher
basic airflow setting will increase the energy efficiency
and capacity but will also decrease the supply air
temperature.
• Formaximumcapacityandenergyefficiency,selectan
airflow at or near the top of the range for that nominal
capacity. See Table 8 (page 21).
• Formaximumdehumidication,selectanairownearthe
middle or bottom of the range for that nominal capacity.
Additionalinformationonhumiditycontrolcanbefound
in the Humidistat and Delay Setting sections.
• Forthermostatswithadehumidieroutput,useaeld
supplied wire to connect the thermostat’s dehumidifier
output to the terminal marked DHUM.The thermostat
should be set so that the DHUM output should be high
(energized)whendehumidification isneeded.See also
Dehumidification Options section.
IMPORTANT! If coil icing is observed, the basic cooling/
heat-pump airflow selected may be too low. Verify the
setting selected is within the range shown inTable 8 and
thatthethesystemisproperlycharged.Pleaserefertothe
instructionssuppliedwiththeoutdoorunit.Ificingcontinues
to occur, raise the selected airflow one or two steps.
NOTE: Variable speed air handlers with SEER ratings
higherthan15arematchedwitha2-stagecoolingoutdoor
unit. They are programmed to operate at 75% of the
selected airflow while the system is in the lo-cool mode
and 100% of the selected airflow while in hi-cool mode.
Dehumidification Options
(B6EM or B6VM Models Only)
Both motor control boards (Figures 15 & 16, page 23)
have a DHUM connection that allows the system to
increase the amount of humidity that is removed from
the circulating air. This is accomplished by reducing the
CFM and allowing the cooling coil to become colder.This
will only occur when there is a call for cooling.There are
many ways that this can be electrically wired.
1.If the room thermostat incorporates a humidity sensor
andDHUMoutput,connecttheDHUMonthethermostat
to the DHUM terminal on the motor control board.
2.If using a separate humidistat, connect the DHUM & R
terminals on the humidistattotheDHUM & Rterminals
on the motor control board of the air handler. In this
option, the DHUM output of the humidistat must be set
to be normally open and closed when there is a call for
humidification. See Figure 10.
3.Ifahumidistatisnotavailable,itisanacceptableoption
to connect the R& DHUM terminals on the motor
control board together with a field supplied wire.This
option causes the blower to run at a reduced CFM for
10 minutes after a call for cooling. NOTE: If outdoor
unit is a heat pump, connect the Oterminal to DHUM.
DHUM
RR
DHUM
HUMIDISTAT
MOTOR
CONTROL BOARD
Figure 10. DHUM Wiring Configuration

16
TROUBLESHOOTING
If the air handler fails to operate, check the following:
• Istheelectricturnedon?
• Isthethermostatoperatingproperly?
• Aretheblowercompartmentdoor(s)inplace?
• Istheairhandlerdisconnectclosed?
• Hasthecircuitbreakertrippedorthecontrolboardfuse
burnedopen?
• Areanymanualresetswitchesopen?
• Isthelterdirtyorplugged?
• IstheLEDonbothcontrolboardsconstantlyON?If
not, refer to Tables 3 or 4 to determine fault condition.
RED LED (AN2) DIAGNOSTIC
OFF Control Fault (No Power)
Flash Blower Fault
ON Normal Operation
Table 3. Air handler Control Board Fault Conditions
CABINET SIZE FILTER SIZE
A 12 x 20 x 1
B 18 x 20 x 1
C 20 x 20 x 1
Table 2. Filter Sizes
UNIT MAINTENANCE
Propermaintenanceismostimportanttoachievethebest
performancefroma airhandler.Someofthecomponents
and their locations are shown in Figure 12 (page 18). If
any component of the air handler must be replaced, use
onlyfactoryauthorizedreplacementpartsspecifiedinthe
Replacement Parts List provided online.
WARNING:
ELECTRICAL SHOCK, FIRE OR EXPLOSION
HAZARD
Failure to follow safety warnings exactly could
result in serious injury or property damage.
Improper servicing could result in dangerous
operation, serious injury, death or property
damage.
•Beforeservicing,disconnectallelectricalpower
to air handler.
•Whenservicingcontrols,labelallwiresprior
to disconnecting. Reconnect wires correctly.
•Verifyproperoperationafterservicing.
• Thesemaintenanceinstructionsareprimarilyintended
toassistqualifiedtechniciansexperiencedintheproper
maintenance and operation of this appliance.
• Always reinstall the doors on the air handler after
servicingorcleaning/changingthefilters.Donotoperate
theairhandlerwithoutalldoorsandcoversinplace.
• Verifythatthethermostatisproperlyinstalledandis
notbeing affectedbydraftsor heat from lamps orother
appliances.
• To achieve the best performance and minimize
equipment failure, it is recommended that a yearly
maintenance checkup be performed. At a minimum,
this check should include the following items:
Air Filter(s)
B6 Series Air Handlers are not supplied with a single air
filter when shipped from the factory. It is recommended
that the filter be cleaned or replaced monthly.Newly built
or recently renovated homes may require more frequent
changinguntilthe constructiondusthasminimized.Filter
sizesshowninTable2areavailableatmostlocalretailers.
WARNING:
Never operate the air handler without a filter in
place. Dust and lint in the return air can build
upon internalcomponents,resulting in loss of
efficiency,equipmentdamage,andpossiblefire.
Filters designed to remove smaller particles such as
pollen, may require additional maintenance.
Blower Compartment
Dirt and lint can create excessive loads on the motor
resulting in higher than normal operating temperatures
and shortened service life. It is recommended that the
blower compartment be cleaned of dirt or lint that may
have accumulated in the compartment or on the blower
and motor as part of the annual inspection.
Blower FanWheel
Inspect the blower wheel blades for accumulations of dirt
andcleanifnecessary.Inspectmountingnutfortightness
when done.
Blower Motor & Assembly
Inspect the blower assembly and motor mounting
bracketsfortightnessandcorrosion.Correctdeficiencies
if necessary.The blower motor contains sealed bearings
and under normal operating conditions, no maintenance
is necessary for the life of the equipment.
Table 4. Motor Control Board Fault Conditions
DIAGNOSTIC GREEN
LED RED LED
Fixed
Speed
Furnaces
Control Fault (No Power) Off Off
Normal Operation On On
Motor Fault On Flash
Twin Fault (no motor fault) Flash On
Communications Fault Flash Flash
Variable
Speed
Furnaces
Control Fault (No Power) Off Off
Normal Operation On On
Motor Fault On Flash
Communications Fault Flash Flash

17
FIGURES &TABLES
Figure 11. B6 Series Physical Dimensions
3/4”
3/4”
3/4”
13”
1 7/8" K.O.
11/8”K.O.
(typ.)
11/4”15/8”
17/8” 11/4”
3 1/4”
2 5/8” 11/8”K.O.
(typ.)
13/4”K.O.
(typ.)
1 7/8”
3 5/8”
5 5/8”
DETAIL “D”
3 1/4”
2 1/4”
15 1/4”13”
SUCTION
LIQUID
“W”
1 1/8”
1 7/8”
7/8" K.O.
“H”
22"
“A”
Cabinet Size H W A Detail D
A 43-5/16 14-3/16 12-3/4 No
B 43-5/16 19-11/16 18-1/4 No
Tall B 49-5/16 19-11/16 18-1/4 No
C 55-15/16 22-7/16 21 Yes

18
Horizontal
Drain PanVertical
Drain Pan
Coil
Assembly
Motor
Mount Kit
Blower
Motor
Transformer
Capacitor
Circuit
Breaker (60A) Heating Element
Assembly
Filter
Tracks
Blower
Wheel
Blower
Housing
Motor Control
Board
Control
Board
Filter
Door
Upper Door
Assembly
Lo
wer Door
Assembly
Figure 12. Air Handler Components

19
AIRFLOW DATA
Dry Coil ESP 0.10 0.20 0.30 0.40 0.50 0.60 0.70 0.80
*24K
A-Cabinet
Low 683 647 607 563 515 463 406 345
Corrected ESP10.00 0.07 0.19 0.30 0.42 0.53 0.65 0.76
Medium 861 823 781 734 682 625 564 498
Corrected ESP10.00 0.00 0.11 0.23 0.36 0.48 0.60 0.72
High 1072 1026 975 920 860 797 730 659
Corrected ESP10.00 0.00 0.00 0.14 0.27 0.40 0.53 0.67
*30K
A-Cabinet
Low 849 825 793 753 704 647 581 508
Corrected ESP10.00 0.04 0.15 0.27 0.38 0.50 0.62 0.74
Medium 1118 1087 1046 997 940 874 799 717
Corrected ESP10.00 0.00 0.04 0.17 0.29 0.42 0.55 0.68
High 1277 1233 1184 1130 1070 1005 935 860
Corrected ESP10.00 0.00 0.00 0.10 0.23 0.36 0.49 0.63
*24K
B-Cabinet
Low 708 690 664 628 584 532 471 401
Corrected ESP10.08 0.19 0.30 0.41 0.53 0.64 0.76
Medium 909 904 886 854 810 753 683 600
Corrected ESP10.10 0.22 0.33 0.46 0.58 0.71
High 1118 1132 1126 1101 1056 992 908 805
Corrected ESP10.09 0.22 0.35 0.49 0.64
*30/*36K
B-Cabinet
Low 953 915 871 821 764 701 631 555
Corrected ESP10.00 0.04 0.16 0.27 0.39 0.51 0.62 0.74
Medium 1265 1232 1188 1133 1067 991 903 805
Corrected ESP10.00 0.00 0.03 0.15 0.28 0.41 0.54 0.68
High 1427 1385 1333 1270 1196 1113 1018 913
Corrected ESP10.00 0.00 0.00 0.09 0.23 0.36 0.50 0.64
*42/48K
B-Cabinet
Low 1324 1302 1271 1233 1187 1134 1072 1003
Corrected ESP10.00 0.06 0.17 0.27 0.38 0.49 0.61 0.72
Medium 1485 1455 1418 1373 1320 1260 1193 1118
Corrected ESP10.00 0.00 0.13 0.24 0.36 0.47 0.58 0.70
High 1637 1601 1558 1506 1447 1380 1305 1223
Corrected ESP10.00 0.00 0.00 0.21 0.33 0.44 0.56 0.68
*48K
C-Cabinet
Low 1605 1606 1592 1565 1524 1468 1399 1316
Corrected ESP10 0.11 0.21 0.31 0.42 0.52 0.63 0.74
Medium 1977 1939 1890 1830 1758 1675 1580 1474
Corrected ESP10 0 0.18 0.28 0.39 0.50 0.61 0.72
High 2264 2182 2095 2003 1906 1805 1698 1586
Corrected ESP10 0 0 0.26 0.37 0.49 0.60 0.71
*60K
C-Cabinet Use B6EM C-Cabinet airflow data.See Table 5 (page 20).
Notes:
1) Airflow is shown in cfm, +/- 5%.
2) External static pressure (ESP) is shown in inches w.c.
3) See unit nameplate or installation instructions for maximum recommended external static pressure.
Table 5. Airflow Data for B6BM Air Handlers

20
B6EM
A-cabinet
Switch Settings
0 = OFF, 1 = ON Cooling or Heating Airflow (CFM)
Dry Coil ESP
1/5 2/6 3/7 4/8 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8
0 0 0 0 585 550 520 460 420 405
1 0 0 0 710 670 650 610 560 530 475 440
0 1 0 0 845 790 765 715 680 655 625 580
1 1 0 0 890 865 840 785 760 710 680 655
0 0 1 0 955 925 900 850 825 790 770 720
1 0 1 0 1030 995 975 940 910 870 840 815
0 1 1 0 1115 1085 1060 1020 995 965 925 905
1 1 1 0 1155 1130 1095 1070 1040 1010 985 950
0 0 0 1 1200 1175 1145 1110 1085 1060 1025 1000
1 0 0 1 1240 1215 1195 1170 1140 1110 1080 1060
0 1 0 1 1320 1290 1265 1240 1215 1185 1160 1130
1 1 0 1 1355 1330 1305 1280 1255 1220 1200 1175
0 0 1 1 1405 1375 1345 1325 1295 1275 1250 1210
1 0 1 1 1440 1415 1385 1355 1325 1290 1255 1215
0 1 1 1 1465 1425 1390 1355 1320 1290 1260 1215
1 1 1 1 1465 1425 1390 1355 1320 1290 1260 1215
B6EM
B-cabinet
Switch Settings
0 = OFF, 1 = ON Cooling or Heating Airflow (CFM)
Dry Coil ESP
1/5 2/6 3/7 4/8 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8
0 0 0 0 600 550 430 390
1 0 0 0 660 610 540 460 425
0 1 0 0 830 750 695 640 580 520
1 1 0 0 860 825 765 690 630 600 525 485
0 0 1 0 935 895 835 790 710 655 620 585
1 0 1 0 1045 975 920 875 830 795 720 685
0 1 1 0 1095 1040 995 950 900 850 805 750
1 1 1 0 1155 1105 1060 1010 965 920 870 825
0 0 0 1 1230 1185 1140 1090 1045 1010 965 920
1 0 0 1 1285 1260 1210 1165 1125 1080 1040 1010
0 1 0 1 1330 1290 1245 1205 1170 1125 1085 1045
1 1 0 1 1395 1365 1315 1275 1235 1205 1160 1130
0 0 1 1 1450 1405 1375 1335 1295 1260 1220 1180
1 0 1 1 1490 1450 1410 1385 1340 1300 1270 1230
0 1 1 1 1530 1485 1460 1425 1380 1350 1310 1280
1 1 1 1 1530 1490 1465 1425 1390 1350 1310 1285
B6EM
C-cabinet
Switch Settings
0 = OFF, 1 = ON Cooling or Heating Airflow (CFM)
Dry Coil ESP
1/5 2/6 3/7 4/8 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8
0 0 0 0 710 580 395
1 0 0 0 830 690 675 530 505
0 1 0 0 930 875 710 665 560 530
1 1 0 0 1065 1015 900 840 800 705 665 635
0 0 1 0 1185 1115 1010 960 925 875 830 745
1 0 1 0 1275 1220 1175 1120 1060 970 930 890
0 1 1 0 1365 1350 1255 1200 1150 1105 1060 1025
1 1 1 0 1480 1430 1370 1325 1265 1225 1185 1140
0 0 0 1 1560 1535 1485 1430 1375 1335 1285 1240
1 0 0 1 1650 1600 1545 1500 1450 1405 1360 1305
0 1 0 1 1730 1685 1660 1610 1570 1520 1470 1420
1 1 0 1 1785 1740 1695 1645 1615 1545 1510 1470
0 0 1 1 1865 1820 1785 1750 1695 1655 1605 1560
1 0 1 1 1920 1890 1850 1805 1765 1715 1675 1640
0 1 1 1 2010 1965 1960 1900 1850 1810 1775 1730
1 1 1 1 2065 2020 1985 1955 1915 1880 1840 1810
NOTE: When matched with two-stage outdoor units, the airflow on low (Y1 or W1) input will be 70% of the values shown in this table.
Table 6. Airflow Data for B6EM (FSHE) Air Handlers