18-CD19D8-18
25
Installer’s Guide
HORIZONTAL APPLICATIONS
Upflow and Downflow furnaces -
All horizontal applica-
tions are left side only. It is always recommended that the
auxiliary drain pan be installed under a horizontally in-
stalled evaporator and/or 90% gas furnace. Connect the
auxiliary drain pan to a separate drain line (no trap is needed
in this line).
The trap must be repositioned to the exterior of the cabinet.
Remove the trap from its present location and reposition the
trap outside of the unit, through the long circular hole, next to
the secondary recuperative cell. Remove the larger drain line
(from the secondary cell) and trim to fit between the second-
ary cell and the new trap location. On upflow units, plug the
hole in the blower deck where the tube went through.
Remove the hose from the induced blower and reposition into
the other drain tap of the inducer, which is located 90°
clockwise around the inducer. Move the cap from that drain
tap to the unused drain tap. On upflow units, plug the hole in
the blower deck where the tube went through. This tube on
downflow units will need to be cut to fit between the inducer
and the trap. On upflow units, this tube may need to be
extended, using the tubing shipped with the furnace.
Connections must be made to an
OPEN/VENTED DRAIN
.
Outdoor draining of the furnace and coil condensate is
permissible if allowed by local codes. Caution should be taken
to prevent drains from freezing or causing slippery conditions
that could lead to personal injury. Excessive draining of
condensate may cause saturated ground conditions that may
result in damage to plants.
NOTE:
Use 1/2" or larger PVC or CPVC pipe and fittings as required
for drain connections (fittings, pipe and solvent cement not
provided).
NOTE:
A corrosion resistant condensate pump must be used if a
pump is required for a specific drain system.
IMPORTANT:
The condensate drain should be installed with provisions to
prevent winter freeze-up of the condensate drain line. Frozen
condensate will block drains, resulting in furnace shutdown. If
the drain line cannot be installed in a conditioned space, then
UL listed heat tape should be applied as required to prevent
freezing (per manufacturer’s instructions). The heat tape should
be rated at 5 or 6 watts per foot at 120 volts. Self-regulating
(preferred) or thermostatically controlled heat tape is required.
Evaporator and furnace condensate drain piping may be
manifolded together. A primary drain vent stack must be
installed and terminated below the outlet of the secondary
heat exchanger drain connection to prevent water from
damaging furnace controls if the primary drain outlet plugs
up. Where the furnace is installed above a finished ceiling,
the primary drain vent stack must be installed such that
overflow from the vent stack opening will flow into an axillary
drain pan in order to prevent water damage to the finished
ceiling below.
Cut off curved end of
Inducer drain hose
DOWNFLOW (HORIZONTAL)
DOWNFLOW (VERTICAL)
Left
side
Use CPVC tubing from Trap outlet,
over burner box to cabinet exit
DOWNFLOW (VERTICAL)
Right
side
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