Install Instructions
20
C
ONDENSATE
D
RAIN
L
INES
& D
RAIN
T
RAP
A condensing gas furnace achieves its high level of efficiency by
extracting heat from the products of combustion to the point
where condensation takes place. The condensate must be col-
lected in the furnace drain trap and routed to an appropriate
drain location in compliance with local and national codes.
Follow the bullets listed below when installing the drain system.
Refer to the following sections for specific details concerning
furnace drain trap installation and drain hose hook ups.
• The drain trap supplied with the furnace must be
used.
• The drain trap must be primed at time of
installation.
• The drain line between furnace and drain location
must meet local and nation codes.
• The drain line between furnace and drain location
must maintain a 1/4 inch per foot downward slope
toward the drain.
• Do not trap the drain line in any other location than at
the drain trap supplied with the furnace.
• If the drain line is routed through an area which may
see temperatures near or below freezing, precautions
must be taken to prevent condensate from freezing
within the drain line.
• If an air conditioning coil is installed with the furnace,
a common drain may be used. An open tee must be
installed in the drain line, near the cooling coil, to
relieve positive air pressure from the coil’s plenum.
This is necessary to prohibit any interference with the
function of the furnace’s drain trap.
NOTE: In vertical installations, air conditioning coil conden-
sate may drain into the furnace trap as long as there is a
trap between the coil and the furnace trap and the drain pipe
is not terminating below the water level of the furnace trap.
GENERAL DRAIN INFORMATION
All furnace models come with a factory installed drain trap.
For vertical installations, the trap will remain in the factory
position except for a counterflow when the installer desires
the drain to exit the right side. All furnace models installed
horizontally require the trap to be relocated. Many drain hoses
have a built–in grommet which will provide a cabinet seal
when installed. See instructions below for your model and
installation position.
NOTE: Both sides of the drain trap must be primed prior
to initial furnace start up
FIELD SUPPLIED DRAIN
Drain the furnace and air conditioning coil if applicable, in
compliance with code requirements. In horizontal or coun-
terflow installations, a field installed rubber coupling will
allow the drain trap to be removed for cleaning. The drain
trap must be primed before initial furnace start up. When
an air conditioning coil drain is connected to the field sup-
plied furnace drain, it must be vented, with an open tee
installed at a height no higher than the bottom of the furnace
collector box to prevent air conditioning condensate from
backing up into the furnace if the common drain was blocked.
UPFLOW MODEL INSTALLED VERTICALLY
The trap and factory installed hoses remain as shipped. The
furnace drain may exit either the right or left side of the
furnace cabinet. Both sides of the cabinet have two .875”
diameter holes which can be used interchangeably for drain
and low voltage wiring purposes. If a higher drain exit is
needed, a .875” diameter hole may be added in the area
shown in Figure 22. Any unused cabinet opening must be
sealed. Do not allow drain hose to sag or trap wa-
ter.
DRAIN EXITING RIGHT SIDE
1. Locate and Install the 45º pipe / hose drain coupling
from the outside of the cabinet (barbed end goes in
the cabinet) through hole in the right side of the cabinet
and secure with two field supplied #8 self-tapping
screws (see Figure 23).
2. Locate the long drain hose #3 and cut at line “A” .
3. Install large end of hose #3 to trap outlet and secure
with 1.25" clamp.
4. Install smaller end of hose #3 on 45º elbow and secure
with 1" clamp.
5. Refer to Field Supplied Drain section for instructions
on field supplied / installed drain on outlet of furnace
trap.
Side Cut-Out
12”
3”
Right side shown.
Acceptable
area for
drain hole.
Figure 23