Setting Equipment

EQUIPMENT IN CONFINED SPACE

ALL AIR FROM OUTSIDE

(All Air Through Ventilated Attic)

CHIMNEY OR GAS

VENT

VENTILATION LOUVERS (Each end of attic)

OUTLET

AIR

G24−200	INLET AIR
FURNACE	INLET AIR
	(Ends 12 in.
	above bottom)

NOTE−The inlet and outlet air openings shall each have a free area of at least one square inch (645 mm2) per 4,000 Btu (1.17 kW) per hour of the total input rating of all equip- ment in the enclosure.

FIGURE 3

EQUIPMENT IN CONFINED SPACE

(ALL AIR FROM OUTSIDE)

WARNING

Do not install the furnace on its front or its back. Do- ing so will adversely affect the operation of the safety control devices, which could result in personal inju- ry or death.

The Lennox G24−200 upflow gas furnace can be installed with rear or bottom return air. If unit is installed on a platform with bottom return air, furnace/filter box must be sealed airtight at the platform to ensure proper and safe operation.

Select a location that allows for required clearances listed on unit rating plate. Also consider gas supply connections, electrical supply, vent connection, installation and service clearances [24 inches (610mm) at unit front] and filter ac- cessibility.

The furnace must be leveled using shims or leveling bolts (field provided). The corner gussets provided in the furnace base will accept leveling bolts.

Return Air Plenum / Filter Box Installation

Return air openings are provided at rear and in bottom of unit. A return air closure panel is shipped secured to the rear opening.

A − Bottom Return Air (Refer to figure 5)

1 − Determine the location of the furnace/filter box.

CHIMNEY

OR GAS

VENT

G24−200

FURNACE

OUTLET AIR

INLET AIR

2 − Cut 50-5/8 x 26-1/8 (128.6cm x 66.4cm) opening in the return air platform.

3 − Fabricate the return air plenum with right angle flanges and insert into the floor opening.

4 − Remove filter box access door and filters.

5 − Apply adhesive-backed foam tape to the bottom of the filter box all around the opening. Position the filter box over the return air plenum. Fasten as required using self-tapping screws provided.

NOTE−Each air duct opening shall have a free area of at least one square inch (645 mm2) per 2,000 Btu (.59 kW) per hour 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 open- ing shall have a free area of at least one square inch (645 mm2) per 4,000 Btu (1.17 kW) per hour of the total input rating of all other equipment in the enclosure.

FIGURE 4

Make sure there is an air tight seal between the platform/return air plenum and filter box.

6 − Apply adhesive-backed foam to the top of the filter box all around the opening. Place furnace over the filter box with sides and rear of furnace and filter box flush. Fas- ten as required.

Make sure there is an air tight seal between the fur- nace and the filter box.

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