18-CD33D1-4
7
Installer’s Guide
UPFLOW INSTALLATION
Standoffs and screws (See Figure 1) 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 align-
ment hole. The drill screws are inserted through the
standoffs then screwed into the furnace flange.
The coil is always placed downstream of the furnace air-
flow.
DOWNFLOW INSTALLATIONS
▲
WARNING
!
FIRE HAZARD
Do NOT install the furnace directly on carpeting, tile
or other combustible material other than wood floor-
ing. For vertical downflow application, subbase (BAY-
BASE205) must be used between the furnace and
combustible flooring. When the downflow furnace is
installed vertically with a cased coil, a subbase is not
required.
Required floor opening:
HORIZONTAL INSTALLATION
The coil and furnace must be fully supported when used
in the horizontal position. It is always recommended that
an auxiliary drain pan be installed under a horizontally
installed evaporator coil or 90% gas furnace. Connect
the auxiliary drain line to a separate drain line (no trap is
needed in this line).
Three brackets (with screws) are included with downflow
furnaces for installation to stabilize and secure the fur-
nace and TXC cased coil in the
horizontal position
. See
Figure 3.
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
furnace. The remaining bracket is placed as close to cen-
ter as possible (horizontally) between the coil case front
and the furnace bottom channel (for downflow/horizon-
tal furnace). Use four of the screws provided to secure
the bracket. The upflow furnace, converted to horizontal,
aligns and attaches the TXC coil as in Figure 1. However,
the coil requires additional support.
The furnace may be installed in an attic or crawl space
in the horizontal position by placing the furnace
on the
left side
(as viewed from the front in the vertical position).
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 Figure 4 & Clearance Table). Line con-
tact is only permissible between lines formed by intersec-
tions of the top and two sides of the furnace casing and
building joists, studs, or framing.
UPFLO
W
FURNA
CE
CASED
COIL
SCREWS
(BOTH SIDES)
STANDOFFS
(BOTH SIDES)
STANDOFFS (4)
DRILL SCREWS (4)
FOR VERTICAL
INSTALLATIONS:
1
SUBBASE CROSS SECTION
FURNACE
FRONT
A (width)
B (depth)
C
D
2
CASED COIL CONNECTION
BRACKET FOR DOWNFLOW FUR-
NACE IN HORIZONTAL
DOWNFLOW ONLY
3
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"
