Lennox MERIT ML195UH Installation Instructions Manual page 31

3 - Install the cap over the clean out opening at the
base of the trap. Secure with clamp. See figure 53.
CONDENSATE TRAP AND PLUG LOCATIONS
(Unit shown in upflow position)
Trap
(same on
right side)
1-1/2 in.
NOTE - In upflow applications where side return
sate trap, filter rack must be installed beyond
condensate trap or trap must be re-located to
avoid interference.
FIGURE 45
4 - Install drain trap using appropriate PVC fittings,
glue all joints. Glue the provided drain trap as
shown in figure 53. Route the condensate line to an
open drain. Condensate line must maintain a 1/4"
downward slope from the furnace to the drain.
5 - Figures 49 and 50 show the furnace and evaporator
coil using a separate drain. If necessary the
condensate line from the furnace and evaporator
coil can drain together. See figures 48, 51 and
52. Upflow furnace (figure 49) - In upflow furnace
applications the field provided vent must be a
minimum 1" to a maximum 2" length above the
condensate drain outlet connection. Any length
above 2" may result in a flooded heat exchanger
if the combined primary drain line were to become
restricted. Horizontal furnace (figure 52) - In
horizontal furnace applications the field provided
vent must be a minimum 4" to a maximum 5" length
above the condensate drain outlet connection.
Any length above 5" may result in a flooded heat
exchanger if the combined primary drain line were
to become restricted.
Rubber
Grommet
Plug
(same on left side)
Page 31
6 - If unit will be started immediately upon completion
of installation, prime trap per procedure outlined in
Unit Start-Up section.
CONDENSATE TRAP LOCATIONS
(Unit shown in upflow position with remote trap)
Field ProvidedVent
Min. 1" Above Condensate
Drain Connection
1" Min.
2" Max.
*5' max.
PV C PipeOnly
Trap Can Be Installed a
Maximum 5' From Furnace
*Piping from furnace must slope down a
minimum 1/4" per ft. toward trap
FIGURE 46
Field Provided Drain Components
Elbow
Tubing
FIGURE 47
T o Drai n
Barbed Fitting
Hose Clamp