b. Remove 2 screws from bottom front panel.
c. Rotate front panel downward to remove.
d. Remove bottom closure panel and set aside for possible use as roll-out protection.
e. Reinstall bottom front panel.
f. Stand furnaces upright.
4. For all horizontal applications:
Return air can only be connected to bottom opening of furnace.
5. Apply 2 factory-supplied foam strips to mating side of each furnace. Locate strips equal distance from top and bottom as shown in Fig. 5.
6. Remove 7/8-in. diameter accessory hole knockouts in blower compartment from mating sides of furnaces. (See Fig. 3.)
7. Insert a plastic snap bushing through the 7/8
″
K.O. from the outside of the casing.
8. Position furnaces on top of each other on platform or suspended supports. Adjust and shim each furnace to align 7/8-in. diameter holes in
both furnaces.
9. Drill two 1/8-in. holes, approximately 1 in. below discharge flange, from inside top of discharge opening and through both furnaces. (See
Fig. 6.) Drill two 1/8-in. holes, approximately 1 in. above return air opening flange, from inside blower compartment and through both
furnaces. (See Fig. 7.)
10. Drive 1 factory-supplied screw through each hole and tighten until furnaces are secure and foam strips have sealed gap between furnaces.
11. Connect return- and supply-air ducts to furnaces. Seal duct connections to prevent air leakage.
12. Move 115-v junction box JB in RH furnace (as viewed from the upflow position) from left-hand side to right-hand side. Refer to furnace
installation instructions for complete details.
13. Go to PROCEDURE 2A for Single Stage Furnaces or PROCEDURE 2B for Two Stage Furnaces.
PROCEDURE 2—CONNECT ELECTRICAL COMPONENTS—HEATING
2A. All Single-Stage Models: 58STA, 58STX, 58DLA, 58DLX, 310AAV, 310JAV, 311AAV, 311JAV, PG8MAA, AND PG8JAA Multipoise
Single-Speed Non-Condensing HSI Furnaces
WARNING: FIRE HAZARD
Failure to follow this warning can cause a fire, personal injury, or death.
Make no connections between the R 24-vac connector in 1 furnace and the R 24-vac connector in other furnace.
See electrostatic discharge precaution on page 2.
Fig. 9a—Attic Installation of Horizontal Furnace Stacked Together
A02242
30˝ Work Platform
Two 2˝ x 4˝
or one 4˝ x 4˝
Sheet Metal
22˝
12
3
/
4
˝
5
3
/
4
˝
17
3
/
4
˝ over all 4
3
/
4
˝ under door
1˝ under furnace
Extend out 12˝ from face
of door
17
3
/
4
˝
—11—
