Lennox MERIT Series Installation Instructions Manual page 28

Condensate Piping
This unit is designed for either right- or left-side exit of
condensate piping. Refer to FIGURE 43 and FIGURE 45
for condensate trap locations.
CONDENSATE TRAP AND PLUG LOCATIONS
Trap
(same on
right side)
1-1/2 in.
FIGURE 43
1 - Determine which side condensate piping will exit
the unit, location of trap, field-provided fittings and
length of PVC pipe required to reach available drain.
NOTE - Do not remove the rubber grommet used to
seal the cabinet on the side not used when installing
the condensate trap.
2 - Use a large flat head screw driver or a 1/2" drive
3 - Install the cap over the clean out opening at the base
4 - Install drain trap using appropriate PVC fittings, glue
5 - FIGURE 46 shows the furnace and evaporator coil
Plug
(same on left
side)
Rubber
Grommet
Page 28
socket extension and remove plug (figure 43) from the
cold end header box at the appropriate location on the
side of the unit. Install provided 3/4 NPT street elbow
fitting into cold end header box. Use Teflon tape or
appropriate pipe dope.
NOTE - Cold end header box drain plugs are facto-
ry installed. Check the unused plug for tightness to
prevent leakage.
of the trap. Secure with clamp. See FIGURE 49.
all joints. Glue the provided drain trap as shown in
FIGURE 49. Route the condensate line to an open
drain.
using a separate drain. If necessary, the condensate
line from the furnace and evaporator coil can drain
together. See FIGURE 47 and FIGURE 48. The field
provided vent must be a minimum 1" to a maximum 2"
length above the condensate drain outlet connection.
NOTE - If necessary the condensate trap may be
installed up to 5 feet away from the furnace. Piping
from furnace must slope down a minimum of 1/4"
per ft. toward trap.
NOTE - Appropriately sized tubing and barbed fit-
ting may be used for condensate drain. Attach to the
drain on the trap using a hose clamp. See FIGURE
44.
Field Provided Drain Components
Elbow
Tubing
FIGURE 44
Barbed Fitting
Hose Clamp