Lennox G61MPV Series User manual

EJwvox )
®
_ 2006 Lennox Industries Inc.
Dallas, Texas, USA
INSTALLATION
INSTRUCTIONS
G61MPV SERIES UNITS
GAS UNITS Technical
505,240M J LJ _.Publications
07/2007 ......
Supersedes 10/2006 Lithe U.S.A.
RETAIN THESE INSTRUCTIONS
FOR FUTURE REFERENCE
Unit Dimensions ............................... 2
G61MPV Parts Arrangement ..................... 3
Shipping and Packing List ....................... 4
Safety Information .............................. 4
General ....................................... 6
Combustion, Dilution & Ventilation Air ............. 6
Installation - Setting Equipment .................. 9
Filters ........................................ 16
Duct System .................................. 17
Pipe & Fittings Specifications ................... 17
Vent Piping Guidelines ......................... 19
Joint Cementing Procedure ..................... 20
Venting Practices ............................. 21
Gas Piping ................................... 32
Electrical ..................................... 34
Integrated Control Board ....................... 41
Unit Start-Up ................................. 51
Gas Pressure Adjustment ...................... 52
High Altitude Information ....................... 53
Other Unit Adjustments ........................ 55
Service ...................................... 56
Ignition Control Board Diagnostic Codes ......... 57
Troubleshooting ............................... 58
Repair Parts List .............................. 66
Vent Pipe Sizing Worksheet .................... 66
Start-Up & Performance Check List .............. 67
AWARNING
Do not store or use gasoline or other
flammable vapors and liquids in the
vicinity of this or any other ap-
pliance.
Installation and service must be
performed by a qualified installer,
service agency or the gas supplier.
WHAT TO DO IF YOU SMELL GAS:
•Do not try to light any appliance.
•Do not touch any electrical switch; do not
use any phone in your building.
•Leave the building immediately.
•Immediately call your gas supplier from a
neighbor's phone. Follow the gas supplier's
instructions.
•If you cannot reach your gas supplier, call
the fire department.
07/07
IIIH]ININIIIIIIIIIIIIII]IIII]IIIIIIII Page 1 505,240M IIHIIIII]IIIIIIIIIIIII]III]IIIIIIIIIIIIIIIIII

"60C and 60D size units installed in upflow applications
that require air volumes over 1800 cfm (850 L/s) must have
one of the following:
1.Single side return air with transition, to accommodate
20 x 25 x 1 in. (508 x 635 x 25 mm) air filter.
Required to maintain proper air velocity.
2. Single side return air with optional RAB Return Air Base
3. Bottom return air.
4. Return air from both sides.
5. Bottom and one side return air.
Refer to Engineering Handbook for additional information.
**Consider sizing requirements for optional IAQ equip-
ment before cutting side return opening.
1Optional External Side Return Air Filter Kit is not for use
with the optional RAB Return Air Base.
,,_ A-_
B-_ _-9/16(14)
t
AIR FLOW
_OPTIONAL
EXTERNAL
SIDE RETURN
AIR FILTER KIT
(Either Side)
SUPPLY AIR
OPENING
t6-1/2
11-5/8(1 5)
(295) Right
23-3/4 (603)
i_-_ 25 (635)
TOP VIEW
28-1/2
I_ (724)
5-1/2 _ _.,91._ 19-7/16 ._1_
$r_ COMBUSTION AIR INTAKE
.... _ _ (Either Side)
( ly \ /EXHAUST AIR OUTLET
9- _/_ /_ (Either Side)
GASP,P,NG,NLET
_11_/_f\ (Either Side)
\.r_ CONDENSATE
L_TRAPCONNECTION
°Oo_ (Either Side)
_ ELECTRICAL INLET
, ,Ei, er i ei
164) ....
I23
1OPTIONAL
EXTERNAL
SIDE RETURN
AIR FILTER KIT
(Either Side) ,o
(1016)
'_' 5/8 (16)
--J_l- 3/4 (19)
9-3/4 (248) 4-1/8 6-3/4
Left (103) (171)
4-7/8 (124) Right
2-1/4 (57) Left -I_
18-3/4 (476) -I_ { 1_2_1_A (584) I
I*OPTIONAL 14"*
I RETURN CUTOUT
I(Either Side)
L1-15/16 (49)
Jl---c ---1-
3/4 (19) *Bottom Return 4-1/4 *Bottom Return
Air Opening (108) Air Opening
FRONT VIEW SIDE VIEW
9/16
91-(14)
A B C
Model No. in. mm in. mm in. mm
G61MPV-36B-045
G61MPV-36B-070 17-1/2 446 16-3/8 416 16 406
G61MPV-36B-071
G61MPV-36C-090
G61MPV-60C-090
G61MPV-60C-091 21 533 19-7/8 454 19-1/2 495
G61MPV-60C-110
G61MPV-60C-111
G61MPV-60D-135 24-1/2 622 23-3/8 546 23 584
Page 2

BURNER BOXASSEMBLY
*G61MPV-36B-045
units are equipped
with two switches.
GAS VALVE
AND MANIFOLD
FLUE
COLLAR
DuralokPlus TM
HEATEXCHANGER
ASSEMBLY
CABINET
COMBUSTION
AIR PRESSURE
PROVE SWITCHES* WARM HEADER
(COLLECTOR)
BOX
INDUCER
BURNER
ACCESS
PANEL
BLOWER
I ACCESS
SIGHT
GLASS
CIRCUIT
BREAKER
TRANSFORMER
\
Two-Stage, Variable Speed
Integrated Control Board
CONDENSER COIL
PRIMARY LIMIT
\
SECONDARY
LIMITS (2)
POWER CHOKE
(5 Ton Only)
DOOR
INTERLOCK
SWITCH
BLOWER MOTOR
FIGURE 1
Page 3

TheG61MPVgasfurnaceisequippedwithatwo-stage,
variablespeedintegratedcontrol.Thiscontrolensures
compatibilitywithLennox'HarmonyIIIzonecontrolsys-
tem,aswellasathermostatwhichprovideshumiditycon-
trol.EachG61MPVisshippedreadyforinstallationinthe
upfiow,downflow,horizontalleftairdischargeorhorizontal
rightairdischargeposition.Thefurnaceisshippedwiththe
bottompanelinplace.Thebottompanelmustberemoved
iftheunitistobeinstalledinupflowapplicationswithbot-
tomreturnair.Thebottompanelmustalsoberemovedand
discardedinalldownfioworhorizontalapplications.
Thefurnaceisequippedforinstallationinnaturalgasap-
plications.Aconversionkit(orderedseparately)isrequired
foruseinpropane/LPgasapplications.
The G61MPV can be installed as either a Direct Vent or
a Non-Direct Vent gas central furnace.
NOTE -In Direct Vent installations, combustion air is taken
from outdoors and flue gases are discharged outdoors. In
Non-Direct Vent installations, combustion air is taken from
indoors and flue gases are discharged outdoors. See fig-
ure 2 for appfications involving roof termination.
DIRECT VENT INSTALLATION
COMBUSTION EXHAUST
AIR INTAKE OUTLET
OUTSIDE OF
HOUSE _
CONDENSATE
DRAIN"_
I
FIGURE 2
NON-DIRECT VENT
INSTALLATION
EXHAUST
OUTLET
COMBUSTION
AIR INTAKE INSIDE
OF HOUSE
CONDENSATE
DRAIN
Package 1 of 1 contains
1 - Assembled G61MPV unit
1 - Bag assembly containing the following:
3 - Screws
3 -Wire nuts
1 - Snap bushing
1 - Snap plug
1 - Wire tie
1 - Condensate trap
1 - Condensate trap cap
2 -2" diameter vent /intake plugs
1 -3" diameter cabinet plug (intake)
1 - 2" diameter debris screen
1 -Logo sticker (for use in downfiow applications)
NOTE -G61MPV-60C-110 and-111 units also include a 2"
diameter ABS street elbow, which is shipped on the blower
deck in the heating compartment. G61MPV-60D-135 units
are shipped with a 3" to 2" ABS reducing elbow.
The following items may also be ordered separately:
1- Thermostat
1 - Propane/LP changeover kit
Check equipment for shipping damage. If you find any
damage, immediately contact the last carrier.
&WARNING
a,CAUTION
Use only the type of gas approved for use with this furnace.
Refer to unit nameplate.
G61MPV units are CSA International certified to ANSI
Z21.47 and CSA 2.3 standards.
In the USA, installation of gas furnaces must conform with
local building codes. In the absence of local codes, units
must be installed according to the current National Fuel
Gas Code (ANSI-Z223.1/NFPA 54). The National Fuel
Gas Code is available from the following address:
American National Standards Institute, Inc.
11 West 42nd Street
New York, NY 10036
In Canada, installation must conform with current National
Standard of Canada CSA-B149 Natural Gas and Propane
Installation Codes, local plumbing or waste water codes
and other applicable local codes.
In order to ensure proper unit operation in non-direct vent
applications, combustion and ventilation air supply must be
provided according to the current National Fuel Gas Code
or CSA-B149 standard.
This furnace is CSA International certified for installation
clearances to combustible material as listed on the unit
nameplate and in the tables in figures 7, 12 and 16. Acces-
sibility and service clearances must take precedence over
fire protection clearances.
NOTE- For installation on combustible floors, the furnace
shall not be installed directly on carpeting, tile, or other
combustible material other than wood flooring.
Page 4

Forinstallationinaresidentialgarage,thefurnacemustbe
installedsothattheburner(s)andtheignitionsourceare
locatednolessthan18inches(457mm)abovethefloor.
Thefurnacemustbelocatedorprotectedtoavoidphysical
damagebyvehicles.Whenafurnaceisinstalledinapublic
garage,hangar,orotherbuildingthathasahazardousat-
mosphere,thefurnacemustbeinstalledaccordingtorec-
ommendedgoodpracticerequirementsandcurrentNa-
tionalFuelGasCodeorCSAB149standard.
NOTE -Furnace must be adjusted to obtain a temperature
rise within the range specified on the unit nameplate. Fail-
ure to do so may cause erratic limit operation.
This G61MPV furnace may be used as a high-static unit
heater. The G61MPV may also be installed in an aircraft
hangar in accordance with the Standard for Aircraft Han-
gars (ANSl/NFPA No. 408-1990).
Installation in parking structures must be in accordance
with the Standard for Parking Structures (ANSI/NFPA No.
88A-1991 ). Installation in repair garages must be in accor-
dance with the Standard for Repair Garages (ANSI/NFPA
No. 88B-1991 ).
This G61MPV furnace must be installed so that its electri-
cal components are protected from water.
When this furnace is used with cooling units, it shall be
installed in parallel with, or on the upstream side of, cooling
units to avoid condensation in the heating compartment.
With a parallel flow arrangement, a damper (or other
means to control the flow of air) must adequately prevent
chilled air from entering the furnace. If the damper is manu-
ally operated, it must be equipped to prevent operation of
either the heating or the cooling unit, unless it is in the full
HEAT or COOL setting.
When installed, this furnace must be electrically grounded
according to local codes. In addition, in the United States,
installation must conform with the current National Electric
Code, ANSI/NFPA No. 70. The National Electric Code
(ANSI/NFPA No. 70) is available from the following ad-
dress:
National Fire Protection Association
1 Battery March Park
Quincy, MA 02269
In Canada, all electrical wiring and grounding for the unit
must be installed according to the current regulations of the
Canadian Electrical Code Part I (CSA Standard C22.1)
and/or local codes.
NOTE -This furnace is designed for a minimum continuous
return air temperature of 60°F (16°C) or an intermittent op-
eration down to 55°F (13°C) dry bulb for cases where a
night setback thermostat is used. Return air temperature
must not exceed 85°F (29 °C) dry bulb.
The G61MPV furnace may be installed in alcoves, closets,
attics, basements, garages, and utility rooms.
This furnace design has not been CSA certified for installa-
tion in mobile homes, recreational vehicles, or outdoors.
Never use an open flame to test for gas leaks. Check all
connections using a commercially available soap solution
made specifically for leak detection.
Lennox does not recommend the use of G61MPV units as
a construction heater during any phase of construction.
Very low return air temperatures, harmful vapors and op-
eration of the unit with clogged or misplaced filters will dam-
age the unit.
G61MPV units may be used for heating of buildings or
structures under construction, if the following conditions
are met:
•The vent system must be permanently installed per
these installation instructions.
• A room thermostat must control the furnace. The use of
fixed jumpers that will provide continuous heating is not
allowed.
• The return air duct must be provided and sealed to the
furnace.
• Return air temperature range between 60°F (16°C) and
80°F (27°C) must be maintained.
• Air filters must be installed in the system and must be
maintained during construction.
• Air filters must be replaced upon construction comple-
tion.
• The input rate and temperature rise must be set per the
furnace rating plate.
• One hundred percent (100%) outdoor air must be pro-
vided for combustion air requirements during construc-
tion. Temporary ducting may supply outdoor air to the
furnace. Do not connect duct directly to the furnace.
Size the temporary duct following these instructions in
section for Combustion, Dilution and Ventilation Air in a
confined space with air from outside.
• The furnace heat exchanger, components, duct sys-
tem, air filters and evaporator coils must be thoroughly
cleaned following final construction clean-up.
• All furnace operating conditions (including ignition, in-
put rate, temperature rise and venting) must be verified
according to these installation instructions.
NOTE -The Commonwealth of Massachusetts stipu-
lates these additional requirements:
• Gas furnaces shall be installed by a licensedplumb-
er or gas fitter only.
• The gas cock must be "T handle" type.
• When a furnace is installed in an attic, the passage-
way to and service area surrounding the equipment
shall be floored.
Page 5

Theseinstructionsareintendedasageneralguideanddo
notsupersedelocalcodesinanyway Consultauthorities
havingjurisdictionbeforeinstallation
Inadditiontotherequirementsoutlinedpreviously,thefol-
lowinggeneralrecommendationsmustbe considered
wheninstallingaG61MPVfurnace:
• Placethefurnaceasclosetothecenteroftheairdis-
tributionsystemaspossibleThefurnaceshouldalsobe
locatedclosetothechimneyorventterminationpoint
• Whenthefurnaceisinstalledinnon-directventapplica-
tions,donotinstallthefurnacewheredraftsmightblow
directlyintoit Thiscouldcauseimpropercombustion
andunsafeoperation
• Whenthefurnaceisinstalledinnon-directventapplica-
tions,donotblockthefurnacecombustionairopening
withclothing,boxes,doors,etcAirisneededforproper
combustionandsafeunitoperation
• Whenthefurnaceisinstalledinanatticor otherinsu-
latedspace,keepinsulationawayfromthefurnace
• Whenthefurnaceis installedin an unconditioned
space,considerprovisionsrequiredtopreventfreezing
ofcondensatedrainsystem
,CAUTION
WARNING
If the G61MPV is installed as a Non-Direct Vent Fur-
nace, follow the guidelines in this section.
NOTE- In Non-Direct Vent installations, combustion air is
taken from indoors and flue gases are discharged out-
doors.
WARNING
In the past, there was no problem in bringing in sufficient
outdoor air for combustion. Infiltration provided all the air
that was needed. In today's homes, tight construction prac-
tices make it necessary to bring in air from outside for com-
bustion, Take into account that exhaust fans, appliance
vents, chimneys, and fireplaces force additional air that
could be used for combustion out of the house, Unless out-
side air is brought into the house for combustion, negative
pressure (outside pressure is greater than inside pressure)
will build to the point that a downdraft can occur in the fur-
nace vent pipe or chimney, As a result, combustion gases
enter the living space creating a potentially dangerous situ-
ation.
In the absence of local codes concerning air for combus-
tion and ventilation, use the guidelines and procedures in
this section to install G61MPV furnaces to ensure efficient
and safe operation You must consider combustion air
needs and requirements for exhaust vents and gas piping
A portion of this information has been reprinted with per-
mission from the National Fuel Gas Code (ANSI-
Z223 1/NFPA 54) This reprinted material is not the com-
plete and official position of the ANSI on the referenced
subject, which is represented only by the standard in its en-
tirety
In Canada, refer to the standard CSA B149 installation
codes
Page 6

ACAUTION
All gas-fired appliances require air for the combustion pro-
cess. If sufficient combustion air is not available, the fur-
nace or other appliance will operate inefficiently and un-
safely. Enough air must be provided to meet the needs of
all fuel-burning appliances and appliances such as ex-
haust fans which force air out of the house. When fire-
places, exhaust fans, or clothes dryers are used at the
same time as the furnace, much more air is required to en-
sure proper combustion and to prevent a downdraft. Insuf-
ficient air causes incomplete combustion which can result
in carbon monoxide.
In addition to providing combustion air, fresh outdoor air di-
lutes contaminants in the indoor air. These contaminants
may include bleaches, adhesives, detergents, solvents
and other contaminants which can corrode furnace compo-
nents.
The requirements for providing air for combustion and ven-
tilation depend largely on whether the furnace is installed in
an unconfined or a confined space.
Unconfined Space
An unconfined space is an area such as a basement or
large equipment room with a volume greater than 50 cubic
feet (1.42 m3) per 1,000 Btu (.29 kW) per hour of the com-
bined input rating of all appliances installed in that space.
This space also includes adjacent rooms which are not
separated by a door. Though an area may appear to be un-
confined, it might be necessary to bring in outdoor air for
combustion if the structure does not provide enough air by
infiltration. If the furnace is located in a building of tight
construction with weather stripping and caulking around
the windows and doors, follow the procedures in the air
from outside section.
Confined Space
A confined space is an area with a volume less than 50 cu-
bic feet (1.42 m3) per 1,000 Btu (.29 kW) per hour of the
com-bined input rating of all appliances installed in that
space. This definition includes furnace closets or small
equipment rooms.
When the furnace is installed so that supply ducts carry air
circulated by the furnace to areas outside the space con-
taining the furnace, the return air must be handled by ducts
which are sealed to the furnace casing and which terminate
outside the space containing the furnace. This is especially
important when the furnace is mounted on a platform in a
confined space such as a closet or small equipment room.
Even a small leak around the base of the unit at the platform
or at the return air duct connection can cause a potentially
dangerous negative pressure condition. Air for combustion
and ventilation can be brought into the confined space ei-
ther from inside the building or from outside.
Air from Inside
If the confined space that houses the furnace adjoins a
space categorized as unconfined, air can be brought in by
providing two permanent openings between the two
spaces. Each opening must have a minimum free area of 1
square inch (645 mm2) per 1,000 Btu (.29 kW) per hour of
total input rating of all gas-fired equipment in the confined
space. Each opening must be at least 100 square inches
(64516 mm2). One opening shall be within 12 inches (305
mm) of the top of the enclosure and one opening within 12
inches (305 mm) of the bottom. See figure 3.
EQUIPMENT IN CONFINED SPACE -ALL AIR FROM INSIDE
ROOF TERMINA] ED_lr
EXHAUST PIPE
'-, _ OPENINGS
•-- (To Adjacent
SIDE WALL _1 Unconfined
ERMINATED EX=
UST PIPE (ALTER- -- __pace)
ATE LOCATION) 361MPV /(
III
I I I I I I I I I I I I I I I I I I
' h ¢"l ¢'
NOTE -Each opening shall havo a free area of at least ono square
inch per 1,000 Btu (645mm 2per .29kW) per hour of the total input
rating of all equipment in the enclosure, but not less than 100 square
inches (64516mm. 2).
FIGURE 3
Air from Outside
If air from outside is brought in for combustion and ventila-
tion, the confined space shall be provided with two perma-
nent openings. One opening shall be within 12"(305mm) of
the top of the enclosure and one within 12" (305mm) dthe
bottom. These openings must communicate directly or by
ducts with the outdoors or spaces (crawl or attic) that freely
communicate with the outdoors or indirectly through verti-
cal ducts. Each opening shall have a minimum free area of
1 square inch per 4,000 Btu (645mm 2 per 1.17kW) per hour
of total input rating of all equipment in the enclosure. When
communicating with the outdoors through horizontal ducts,
each opening shall have a minimum free area of 1 square
inch per 2,000 Btu (645mm 2 per .59kW) per total input rat-
ing of all equipment in the enclosure (See figure 4).
Page 7

EQUIPMENT IN CONFINED SPACE - ALL AIR FROM OUTSIDE
(Inlet Air from Crawl Space and Outlet Air to Ventilated Attic)
ROOF TERMINATED
EXHAUST PIPE
VENTILATION LOUVERS
(Each end of attic)
\ II I
OUTLET
AIR
IINATED
JST PIPE VENTIL
LOU_.
(":RNATE _6I MP_ INLET (For un
ATION) AIR %IL." crawl .'pace)
/
I_1 I" rrrm
NOTE-The inlet and outlet air openings shall each have a free area
of at least one square inch per 4,000 Btu (645mm2per 1.17kW) per
hour of the total input rating of all equipment in the enclosure.
FIGURE 4
If air from outside is brought in for combustion and ventila-
tion, the confined space must have two permanent open-
ings, One opening shall be within 12 inches (305 mm) of the
top of the enclosure and one opening within 12 inches (305
mm) of the bottom. These openings must communicate di-
rectly or by ducts with the outdoors or spaces (crawl or at-
tic) that freely communicate with the outdoors or indirectly
through vertical ducts, Each opening shall have a minimum
free area of 1 square inch (645 mm 2) per 4,000 Btu (1.17
kW) per hour of total input rating of all equipment in the en-
closure, See figures 4 and 5. When communicating with
the outdoors through horizontal ducts, each opening shall
have aminimum free area of 1 square inch (645 mm2) per
2,000 Btu (.56 kW) per total input rating of all equipment in
the enclosure, See figure 6,
When ducts are used, they shall be of the same cross-sec-
tional area as the free area of the openings to which they
connect. The minimum dimension of rectangular air ducts
shall be no less than 3 inches (75 mm). In calculating free
area, the blocking effect of louvers, grilles, or screens must
be considered. If the design and free area of protective cov-
ering is not known for calculating the size opening required,
it may be assumed that wood louvers will have 20 to 25 per-
cent free area and metal louvers and grilles will have 60 to
75 percent free area, Louvers and grilles must be fixed in
the open position or interlocked with the equipment so that
they are opened automatically during equipment opera-
tion,
EQUIPMENT IN CONFINED SPACE - ALL AIR FROM OUTSIDE
(All Air Through Ventilated Attic)
7
ROOF TERMINATED VENTILATION LOUVERS
EXHAUST PIPE (Each end of attic)
TERMINATED
EXHAUSTPIPE
(ALTERNATE
LOCATION)
INLET AIR
(Ends 12"above
bottom)
NOTE-The inlet and outlet air openings shall each have a free area of
at least one square inch per 4,000 Btu (645mm2per 1.17kW) per hour
of the total input rating of all equipment in the enclosure.
FIGURE 5
EQUIPMENT IN CONFINED SPACE -
ALL AIR FROM OUTSIDE
ROOF TERMINATED
EXHAUST PIPE
SIDE WALL
TERMINATED
EXHAUSTPtPE
(ALTERNATE
LOCATION)
NO TE-Each air duct opening shaft have a free area of at least one
square inch per 2,000 Btu (645mm2per. 59kW) per hour of the total
input rating of all equipment in the enclosure, ff the equipment room
is located against an outside wall and the air openings communi-
cate directly with the outdoors, each opening shaft have a free area
of at least 1 square inch per 4,000 Btu (645mm 2per 1.17kW) per
hour of the total input rating of aft other equipment in the enclosure.
FIGURE 6
Page 8

&WARNING
Select a location that allows for the required clearances
that are listed on the unit nameplate. Also consider gas
supply connections, electrical supply, vent connection,
condensate trap and drain connections, and installation
and service clearances [24 inches (610 mm) at unit front].
The unit must be level from front to back and side to side.
NOTE -G61MPV-36B and -36C units with 1/2 hp blower
motors are equipped with three flexible legs and one rigid
leg. The rigid leg is equipped with a shipping bolt and a flat
white plastic washer (rather than the rubber mounting
grommet used with a flexible mounting leg). The bolt and
washer must be removed before the furnace is placed
into operation. After the bolt and washer have been re-
moved, the rigid leg will not touch the blower housing.
NQ TE -G61MPV-60D-135 units are equipped with a ship-
ping pad under the blower housing. Remove the shipping
pad prior to operation.
Allow for clearances to combustible materials as indicated
on the unit nameplate. Minimum clearances for closet or al-
cove installations are shown in figures 7, 12 and 16.
WARNING
WARN ING
Upflow Applications
The G61MPV gas furnace can be installed as shipped in
the upflow position. Refer to figure 7 for clearances.
Installation Clearances
Top
Left Side Right Side
;q
Bottom (Floor)
............................................... T...............................................
Top/Plenum i 1 in. (25 ram)
*Front IO
."................... ..................................................................
Sides i 01-
t
Vent i O
............................................... _................................................
Floor i O:_
| ............................................... _............................................... ._
*Front clearance in alcove installation must be 24 in. (610 ram).
Maintain a minimum of 24 in. (610 ram) for front service access.
TAllow proper clearances to accommodate condensate trap and
vent pipe installation.
| :_For installations on a combustible floor, do not install the fur-
inace directly on carpeting, tile or other combustible materials oth-
ier than wood flooring.
=================================================================================================
FIGURE 7
Return Air -- Upflow Units
Return air can be brought in through the bottom or either
side of the furnace installed in an upfiow application. If the
furnace is installed on a platform with bottom return, make
an airtight seal between the bottom of the furnace and the
platform to ensure that the furnace operates properly and
safely. The furnace is equipped with a removable bottom
panel to facilitate installation.
Markings are provided on both sides of the furnace cabinet
for installations that require side return air. Cut the furnace
cabinet at the maximum dimensions shown on page 2.
NOTE -When air volumes over 1800 cfm (850 L/s) are
required with 60C or 60D models in an upflow applica-
tion, the following return air options are available:
1-Return air from single side with transfion which will
accommodate 20 x25 x I in. (508 x635 x25 mm) air filter.
(Required to maintain proper air velocity.) See figure 8.
2 - Return air from single side with optional RAB Return
Air Base. See figure 10.
3-Return air from bottom.
4-Return air from both sides.
5-Return air from bottom and one side.
Refer to Engineering Handbook for additional information.
Page 9

G61MPV applications which include side return air and
a condensate trap installed on the same side of the
cabinet require either a return air base or field-fabri-
cated transition to accommodate an optional IAQ ac-
cessory taller than 14.5".
Side Return Air
(with transition and filter)
20" X25"X 1"
(508mm X635mm X 25mm)
Air Filter
/
Retu rn Air
Plenum
Transition
FIGURE 8
Removing the Bottom Panel
Remove the two screws that secure the bottom cap to the
furnace. Pivot the bottom cap down to release the bottom
panel, Once the bottom panel has been removed, reinstall
the bottom cap. See figure 9.
Removing the Bottom Panel
Screw
\/
Bottom
Bottom Cap
FIGURE 9
Page 10