
4
PRODUCT DESIGN Notes:
1. InstallermustsupplyoneortwoPVC pipes:oneforcom-
bustionair(optional)andonefortheflueoutlet(required).
Ventpipemustbeeither2”or3” in diameter, depending
uponfurnaceinput,numberofelbows,lengthofrunand
installation (1 or 2 pipes). The optional Combustion Air
Pipeisdependentoninstallation/coderequirements and
must be 2” or 3” diameter PVC.
2. Linevoltagewiringcanenterthroughtherightor leftside
ofthefurnace.Lowvoltage wiring can enter through the
rightor left side offurnace.
3. Conversionkits for propanegasoperationare available.
4. Installer must supply the following gas line fittings, de-
pendingon which entrance isused:
Left -- Two 90º Elbows, one close nipple and one 2.5"
nipple,straight pipe.
Right --Straightpipe to reach gasvalve.
Accessibility Clearances (Minimum)
POSITION* FRONT SIDES REAR TOP FLUE FLOOR
Upflow30010 C
Horizontal Alcove 6 0 4 0 C
*= All positioning is determined as installed unit isviewed from the front.
C= If placed on combustible floor, floor MUST be wood only.
POSITION* FRONT SIDES REAR TOP FLUE FLOOR
Upflow10010NC
Horizontal Alcove 6 0 4 0 C
*= All positioning is determined as installed unit isviewed from the front.
C= If placed on combustible floor, floor MUST be wood only.
*MVM96* MINIMUM CLEARANCES TO COMBUSTIBLE MATERIALS
(INCHES)
NC= For instalaltion on non-combustible floors only. A combustible
subbase must be used for installations on combustible flooring.
*CVM96 MINIMUM CLEARANCES TO COMBUSTIBLE MATERIALS
(INCHES)
NC= For instalaltion on non-combustible floors only. A combustible
subbase must be used for installations on combustible flooring.
AlcoveIllustration
REAR
SIDE
SIDE
LCOVE
24"atfront is required forservicing orcleaning.
Note: Inall cases accessibility clearanceshalltake prece-
denceover clearancesfromtheenclosure where accessibil-
ityclearancesaregreater. Alldimensionsaregivenininches.
GeneralOperation
Models covered by this manual come with a new 4-wire
communicating PCB. When paired with a compatible
communicatingindoorunitanda CTK0*AA communicating
thermostat,thesemodelscansupport4-wirecommunication
protocolandprovidemoretroubleshootinginformation.These
models are also backward compatible with the non-
communicatingthermostat wiring.
The *CVM96 and *MVM96 furnaces are equipped with an
electronic ignition device used to light the burners and an
induceddraft blower to exhaust combustionproducts.
Aninterlockswitchprevents furnace operation if theblower
door is not in place. Keep the blower access door in place
exceptforinspection and maintenance.
This furnace is also equipped with a self-diagnosing elec-
tronic control module. In the event a furnace component is
notoperating properly, the controlmoduleLED will flashon
and off in a factory-programmed sequence, depending on
theproblemencountered. This light canbe viewedthrough
theobservationwindowin the blower access door.Refer to
theTroubleshootingChartforfurther explanation oftheLED
codesandAbnormal Operation - Integrated Ignition Control
section in the Service Instructions for an explanation of the
possibleproblem.
Theratedheatingcapacityof the furnace should be greater
thanor equal to thetotalheat loss ofthe areatobe heated.
The total heat loss should be calculated by an approved
methodorinaccordance with “ASHRAE Guide” or “Manual
J-LoadCalculations” published by theAirConditioningCon-
tractors of America.
*Obtain from: American National Standards Institute 1430
BroadwayNewYork,NY10018
LocationConsiderations
• The furnace should be as centralized as is practical
with respect to the air distribution system.
• Donotinstallthefurnacedirectly on carpeting, tile, or
combustiblematerialotherthanwood flooring.
• When suspending the furnace from rafters or joists,
use 3/8" threaded rod and 2” x 2” x 3/8” angle as
shownintheInstallationand ServiceInstructions.The
length of the rod will depend on the application and
clearancenecessary.
• When installed in a residential garage, the furnace
mustbe positioned so theburnersandignitionsource
are located not less than 18 inches (457 mm) above
the floor and protected from physical damage by ve-
hicles.