
PRODUCT DESIGN
4
4. Installer must supply the following gas line fittings, de-
pendingonwhich entrance is used:
Left --Two 90° Elbows, one close nipple, straight pipe
Right --Straightpipe to reach gas valve.
Accessibility Clearances (Minimum)
POSITION* FRONT SIDES REAR TOP FLUE FLOOR
Upflow30010C
Horizontal 3 6 0 6 0 C
*= All positioning is determined as installed unit is viewed from the front.
C= If placed on combustible floor, floor MUST be wood only.
GMV95 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.
36"atfrontisrequiredforservicingorcleaning.
Note: In all cases accessibility clearance shall take
precedence over clearances from the enclosure where
accessibility clearances are greater. All dimensions are
givenininches.
High Altitude Derate
Whenthisfurnaceisinstalledathighaltitude,theappropriate
High Altitude orifice kit must be installed. This is required
due to the natural reduction in the density of both the gas
fuel and combustion air as altitude increases. The kit will
provide the proper design certified input rate within the
specifiedaltituderange.
Natural Propane Natural Propane Natural Propane
GMV950453BX*
GMV950704CX* No
Change LPM-05*
#55 Orifice No
Change
HANG13
#44
Orifice
HALP11
#56 Orifice HAPS28 HANG14
#45
Orifice
HALP11
#56
Orifice HAPS28
GMV950905DX*
GMV951155DX* No
Change LPM-05*
#55 Orifice No
Change
HANG13
#44
Orifice
HALP11
#56
Orifice HAPS29 HANG14
#45
Orifice
HALP11
#56
Orifice HAPS29
9,001 - 11,000 Feet
"STANDARD" and "HIGH ALTITUDE" KITS
Furnace ID Blwr
Pressure
Switch
Gas Orifices
0 - 7,000 Feet
(Standard Altitude) 7,001 - 9,000 Feet
Gas Orifices
ID Blwr
Pressure
Switch
ID Blwr
Pressure
Switch
Gas Orifices
Highaltitudekitsarepurchasedaccordingtotheinstallation
altitudeandusageofeithernaturalorpropanegas.Referto
the chart above for a tabular listing of appropriate altitude
rangesandcorrespondingmanufacturer’shighaltitudeNatural
GasandPropaneGaskits.Foratabularlistingofappropriate
altituderangesandcorrespondingmanufacturer'sHighAltitude
PressureSwitchkits,refertoeitherthePressureSwitchTrip
Points&UsageChartinthismanualortheAccessoryCharts
inServiceInstructions.
GeneralOperation
TheGMV95furnacesareequippedwithanelectronic ignition
device to light the burners and an induced draft blower to
exhaustcombustion products.
An interlock switch prevents furnace operation if the blower
door is not in place. Keep the blower access doors in place
exceptforinspectionand maintenance.
Thisfurnaceisalsoequippedwithaself-diagnosingelectronic
control module. In the event a furnace component is not
operatingproperly,the control module LED willflashon and
off in a factory-programmed sequence, depending on the
problem encountered. This light can be viewed through the
observation window in the blower access door. Refer to the
TroubleshootingChartforfurtherexplanationoftheLEDcodes
andAbnormal Operation - IntegratedIgnitionControlsection
intheService Instructions for an explanation ofthe possible
problem.
The rated heating capacity of the furnace should be greater
than or equal to the total heat loss of the area to be heated.
The total heat loss should be calculated by an approved
method or in accordance with “ASHRAE Guide” or “Manual
J-Load Calculations” published by the Air Conditioning
ContractorsofAmerica.
*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.
• Do not install the furnace directly on carpeting, tile, or
combustiblematerialotherthanwoodflooring.
• When suspending the furnace from rafters or joists,
use3/8"threadedrod and2”x 2”x1/8”angleasshown
intheInstallationandServiceInstructions.Thelength
ofthe rod willdependonthe application andclearance
necessary.
• Wheninstalledinaresidentialgarage,thefurnacemust
be positioned so the burners and ignition source are
located not less than 18 inches (457 mm) above the
floorand protected from physical damage byvehicles.
Notes:
1. Installermust supply one or two PVC pipes:oneforcom-
bustionair (optional)andone fortheflue outlet(required).
Vent pipe must be either 2” or 3” in diameter, depending
uponfurnaceinput, number of elbows, lengthof run and
installation (1 or 2 pipes). The optional Combustion Air
Pipeisdependent on installation/code requirements and
must be 2” or 3” diameter PVC.
2. Linevoltagewiringcan enter through the right or left side
of the furnace. Low voltage wiring can enter through the
rightor left side of furnace.
3. Conversionkitsfor propane gas and high altitude natural
and propane gas operation are available. See HighAlti-
tudeDeratechart for details.