CRITICAL COIL PROJECTION
The coil assembly must be located in the duct such that a minimum dis- tance is maintained between the top of the coil and the top of the duct. Refer to Table 2.
COIL / FURNACE ASSEMBLY - HC SERIES COILS
These coils are supplied ready to be installed in a right hand position or a left hand position. When used in conjunction with a horizontal furnace (blow through) application, the coil should be oriented with the opening of the “A” coil closest to the furnace. See Figure 7.
NOTICE
Each coil is shipped with an external tie plate that should be used to secure the coil to the furnace. It should be installed on the back side of the coil using the dimpled pilot holes. See Figure 7.
Use tie plate |
supplied with coil |
Gas Furnace |
FIGURE 7: Horizontal Left or Right application (Right Shown)
DOWNFLOW DUCT CONNECTORS
All downflow installations must use a suitable duct connector approved by the furnace manufacturer for use with this furnace. The duct connec- tors are designed to be connected to the rectangular duct under the floor and sealed. Refer to the instructions supplied with the duct con- nector for proper installation. Refer to the separate accessory parts list at the end of these instructions for the approved accessory duct con- nectors.
FURNACE
WARM AIR PLENUM
WITH 1” FLANGES
RESIDENTIAL AND MODULAR HOME UPFLOW RETURN PLENUM CONNECTION
Return air may enter the furnace through the side(s) or bottom depend- ing on the type of application. Return air may not be connected into the rear panel of the unit.
SIDE RETURN APPLICATION
Side return applications pull return air through an opening cut in the side of the furnace casing. This furnace is supplied with a bottom block- off panel that should be left in place if a side return is to be used. If the furnace is to be installed on a flat, solid surface, this bottom panel will provide an adequate seal to prevent air leakage through the unused bottom opening. However, if the furnace is to be installed on a surface that is uneven, or if it is to be installed on blocks or otherwise raised off the floor, it will be necessary to seal the edges of the bottom panel to the casing using tape or other appropriate gasket material to prevent air leakage.
BOTTOM RETURN AND ATTIC INSTALLATIONS
Bottom return applications normally pull return air through a base plat- form or return air plenum. Be sure the return platform structure or return air plenum is suitable to support the weight of the furnace.
The internal bottom panel must be removed for this application.
Attic installations must meet all minimum clearances to combustibles and have floor support with required service accessibility.
DOWNFLOW APPLICATION
For downflow applications, the furnace must be turned
HORIZONTAL APPLICATION
FIGURE 9: Horizontal Application
This furnace may be installed in a horizontal position on either side as shown above. It must not be installed on its back.
ATTIC INSTALLATION
FIBERGLASS
INSULATION
FIBERGLASS TAPE
UNDER FLANGE
COMBUSTIBLE FLOOR
BASE ACCESSORY
FIGURE 8: Combustible Floor Base Accessory
Line contact only permissible between lines formed by the intersection of furnace top and two sides and building joists, studs or framing
Filter rack |
|
must be a minimum |
|
distance | Gas Piping |
of 18” (45.7 cm) |
|
from the |
|
furnace |
|
Supply
Air
Vent (Maintain required clearances to combustibles)
| Sheet metal in |
| front of furnace |
| combustion air |
12” | Openings is |
| |
| Recommended |
12” 
30” MIN. Work Area
Return
AirSediment
Trap
FIGURE 10: Typical Attic Installation
Johnson Controls Unitary Products | 7 |
