18-CD37D1-2-EN
29
Installer’s Guide
Upflow and Downflow furnaces -
All horizontal applications
are left side only. It is always recommended that the auxiliary
drain pan be installed under a horizontally installed 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
VERTICAL APPLICATIONS
Upflow furnace -
The connection tubing for left and right side
drainage is shipped in the blower compartment. Install the con-
nection tubing from the trap to the side of the unit and trim all
excess tubing to avoid kinks.
Downflow furnace -
Use RTV silicon sealant to connect the
fitting to the trap for ease of removal when cleaning the trap.
For left side drain a 1/2" slip PVC fitting is needed. See Figure
51.
To change to a right side drain, remove the drain lines from the
trap, rotate the trap 180° so it exits to the right, then reconnect
the lines. Start with a 1/2" 90° CPVC street elbow connected
to the trap using RTV silicon sealant. Run 1/2" CPVC pipe to a
CPVC elbow. Run 1/2" CPVC pipe from the elbow out through
the right side knock-out. See Figure 52.
HORIZONTAL APPLICATIONS
Figure 49. UPFLOW (VERTICAL)
Left side
Use
extension
hose here
Figure 50. UPFLOW HORIZONTAL 21" & 24" UNITS
(Left side only)
Figure 48. UPFLOW HORIZONTAL
17" UNITS (Left side only)
Use Inducer Drain
hose without
extension
Right side
Figure 47. UPFLOW (VERTICAL)
