Page 6
EQUIPMENT IN CONFINED SPACE
ALL AIR FROM OUTSIDE
(All Air Through Ventilated Attic)
NOTE-The inlet and outlet air openings shall each have a free area
of at least 5.5cm
2
per 1 kW (1 square inch per 4000 Btuh) of the total
input rating of all equipment in the enclosure.
CHIMNEY
OR GAS
VENT
WATER
FURNACE
OUTLET
AIR
VENTILATION LOUVERS
(Each end of attic)
INLET AIR
[Ends 305mm
(12") above botĆ
tom]
G24MCE
FURNACE
FIGURE 3
EQUIPMENT IN CONFINED SPACE
ALL AIR FROM OUTSIDE
OUTLET AIR
INLET AIR
WATER
FURNACE
CHIMNEY
OR GAS
VENT
NOTE-Each air duct opening shall have a free area of at least 3cm
2
per 1 kW
(1 square inch per 2000 Btuh) of the total input rating of all equipment in the
enclosure. If the equipment room is located against an outside wall and the
air openings communicate directly with the outdoors, each opening shall
have a free area of at least 5.5cm
2
per 1 kW (1 square inch per 4000 Btuh) of
the total input rating of all other equipment in the enclosure.
G24MCE
FURNACE
FIGURE 4
Setting Equipment
The Lennox G24MCE multi-position gas furnace can be
installed as shipped in upflow position or in horizontal
position with right-hand or left-hand discharge. The furĆ
nace can easily be converted for downflow applications.
Select unit location that will allow for required clearances
listed on the unit rating plate. Also consider gas supply
connections, electrical supply, vent connection and
installation and service clearances [610mm (24 in.)] at
unit front.
NOTE - 1/3 and 1/2 hp fan motors are equipped with eiĆ
ther four flexible mounting legs or 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).
This shipping bolt and flat washer must be removed beĆ
fore the furnace is put into operation. Once the shipping
bolt and washer are removed, the rigid leg will not touch
the fan housing.
UPFLOW APPLICATIONS
The Lennox G24MCE furnace is shipped in a standard
upflow position. Level the furnace using shims or leveling
bolts. Knockouts are provided in unit base to install field-
provided leveling bolts. Allow for clearances to combusĆ
tible materials as indicated on the unit rating plate. MiniĆ
mum clearances for cupboard or alcove installations are
shown in figure 5.
In upflow applications, return air can be brought in
through the bottom or either side of the furnace. If a furĆ
nace with bottom return air is installed on a platform,
make an airtight seal between the bottom of the furnace
and the platform to ensure proper and safe operation.
Knockouts are provided on both sides of the furnace cabiĆ
net for installations with side return air. When side return
air is used, seal the bottom of the furnace using the panel
provided.
An upflow filter rack is provided. The adjustable rack can
be installed beneath the furnace (flush with cabinet
edges) for bottom return air applications or on the side of
the furnace for side return air.
NOTE - A sheet metal filter puller is provided along with
filter kit. In bottom return air applications, filter puller must
be installed between frame and filter to hold filter in place.
152mm (6 in.)
25mm (1 in.)
UPFLOW APPLICATION
INSTALLATION CLEARANCES
VENT
CONNECTOR
TYPE
SINGLE WALL
TWIN WALL
TOP
*FRONT
51mm (2 in.)
BACK
SIDES
FLUE
25mm (1 in.)
RIGHT
SIDE
LEFT
SIDE
TOP
BOTTOM
*Front clearance in alcove installation must be a miniĆ
mum of 610mm (24 in.) for service access.
**On combustible floor with non-combustible protecĆ
tion. NC - Non-Combustible
**NC
BOTTOM
**NC
51mm (2 in.)
25mm (1 in.)
25mm (1 in.)
25mm (1 in.)
25mm (1 in.)
25mm (1 in.)
FIGURE 5
