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 10.
Removing the Bottom Panel |
Screw |
Bottom Cap |
Bottom Panel |
FIGURE 10
Horizontal Application
Installation Clearances
Top
Left |
| FLOW | Right |
| AIR | ||
|
|
| |
End |
|
| End |
| Bottom |
|
|
Vent Connector | Type C |
| Type B1 |
Type |
| ||
|
|
| |
Top | 0 |
| 0 |
*Front | 2−1/4 in. (57 mm)** | 2−14 in. (57 mm) |
|
|
|
Back | 0 | 0 |
|
|
|
Ends | 2 in. (51 mm) | 2 in. (51 mm) |
|
|
|
Vent | 6 in. (152 mm) | 1 in. (25 mm) |
|
|
|
Floor | 0‡ | 0‡ |
*Front clearance in alcove installation must be 24 in. (610 mm). Maintain a minimum of 24 in. (610 mm) for front service access. ** 3−1/4 in. if single wall vent pipe is used.
‡For installations on a combustible floor, do not install the furnace directly on carpeting, tile or other combustible materials other than wood flooring.
FIGURE 11
Horizontal Applications
The SL280UHV furnace can be installed in horizontal ap- plications. Order kit number 51W10 (or use equivalent) from Lennox.
Allow for clearances to combustible materials as indicated on the unit nameplate. Minimum clearances for closet or al- cove installations are shown in figure 11.
This furnace may be installed in either an attic or a crawl- space. Either suspend the furnace from roof rafters or floor joists, as shown in figure 12, or install the furnace on a platform, as shown in figure 13.
Typical Horizontal Application |
Unit Suspended in Attic or Crawlspace |
Bracket |
Metal Strap |
Bottom Cap |
3/16 inch |
Air Flow |
FIGURE 12
NOTE − Heavy−gauge perforated sheet metal straps may be used to suspend the unit from roof rafters or ceiling joists. When straps are used to suspend the unit in this way, support must be provided for both the ends. The straps must not interfere with the plenum or exhaust pip- ing installation. Cooling coils and supply and return air plenums must be supported separately.
NOTE − When the furnace is installed on a platform in a crawlspace, it must be elevated enough to avoid water damage and to allow the evaporator coil to drain.
Return Air −− Horizontal Applications
Return air must be brought in through the end of a furnace installed in a horizontal application. The furnace is equipped with a removable bottom panel to facilitate installation. See figure 10.
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