6
18-CD31D1-5
Installer’s Guide
FURNACE
FRONT
A (width)
B (depth)
C
D
3
UPFLO
W
FURNA
CE
CASED
COIL
SCREWS
(BOTH SIDES)
STANDOFFS
(BOTH SIDES)
STANDOFFS (4)
DRILL SCREWS (4)
FOR VERTICAL
INSTALLATIONS:
1
2
7. A furnace shall be installed so electrical components
are protected from water.
8. If the furnace is installed in a
residential garage
, it
must be installed so that the burners, and the ignition
source are located not less than 18 inches above the
floor and the furnace must be located or protected to
avoid physical damage from vehicles.
UPFLOW INSTALLATION
Standoffs and screws (See Figure 1, page 6) are included
with the cased coils for attachment to the furnace. There
are clearance alignment holes near the bottom of the coil
wrapper. Drill screws are used to engage the furnace top
flanges. The standoff is inserted into the cabinet alignment
hole. The drill screws are inserted through the standoffs
then screwed into the furnace flange. The coil is always
placed downstream of the furnace airflow. The above
instructions apply only if the coil is on top of an upflow
furnace.
DOWNFLOW INSTALLATION
▲
WARNING
!
Do not install the furnace directly on carpeting, tile or
other combustible material other than wood flooring. For
vertical downflow application, subbase (BAYBASE205)
must be used between the furnace and combustible floor-
ing. When the downflow furnace is installed vertically
with a cased coil, a subbase is not required.
REQUIRED FLOOR OPENING: (DOWNFLOW)
See Figure 3 and Table 1
TABLE 1
CABINET
WIDTH
RETURN
DUCT WIDTH
FLOOR OPENING PLENUM OPENING
"A"
"B"
"C"
"D"
17-1/2"
16-1/4"
16-5/8"
20-1/8"
15-5/8"
19-3/8"
21"
19-3/4"
20-1/8"
20-1/8"
19-1/8"
19-3/8"
24-1/2"
23-1/4"
23-5/8"
20-1/8"
22-5/8"
19-3/8"
HORIZONTAL INSTALLATION
The coil and furnace must be fully supported when used in
the horizontal.
Three brackets (with screws) are included with downflow
furnaces for installation to stabilize and secure the furnace
and TXC cased coil in the
horizontal position
. See Fig-
ure 4.
IMPORTANT:
The 2/4TXC cased coil must be placed downstream of the
furnace. In horizontal installations, the apex of the coil
may point either toward or away from the furnace. See the
2/4TXC coil Installer's Guide for more details.
The cased coil is secured to the furnace and both the fur-
nace
and
the cased coil must be properly supported. The
brackets mount using the rear screws on the coil case and
use the screws provided to secure the bracket to the fur-
nace. The remaining bracket is placed as close to center as
possible (horizontally) between the coil case front and the
furnace bottom channel (for downflow/horizontal furnace).
Use four of the screws provided to secure the bracket.
This furnace may be installed in an attic or crawl space in
the horizontal position by placing the furnace on the left or
right side (as viewed from the front in the upright posi-
tion). The horizontal furnace installation in an attic should
be on a service platform large enough to allow for proper
clearances on all sides and service access to the front of
the furnace (See Clearance Table on Outline Drawings and
Figure 5).
If the furnace is suspended using perforated steel strap
(plumber’s strap), it must be supported at all four corners
and in the middle at the front of the furnace. The forward
most screw on the side of the furnace may be used to con-
nect the strapping (See Figure 5). Line contact is only per-
missible between lines formed by the intersection of the top
and two sides of the furnace casing and the building joists,
studs, or framing.
CASED COIL CONNECTION
BRACKET FOR DOWNFLOW FUR-
NACE IN HORIZONTAL
4
5
Typical Upflow/Horizontal Attic Installation
