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2 - For furnaces with a 1/2” drain connection use a 3/8
allen wrench and remove plug (figure 35) from the cold
end header box at the appropriate location on the side
of the unit. Install field-provided 1/2 NPT male fitting
into cold end header box. For furnaces with a 3/4”
drain connection use a large flat head screw driver or a
1/2” drive socket extension and remove plug. Install
provided 3/4 NPT street elbow fitting into cold end
header box. Use Teflon tape or appropriate pipe dope.
3 - Install the cap over the clean out opening at the base
of the trap. Secure with clamp. See figure 43.
4 - Install drain trap using appropriate PVC fittings, glue
all joints. Glue the provided drain trap as shown in fig
ures 43. Route the condensate line to an open drain.
Condensate line must maintain a 1/4” downward slope
from the furnace to the drain.
FIGURE 35
CONDENSATE TRAP AND PLUG LOCATIONS
(Unit shown in upflow position)
NOTE - In upflow applications where side return
air filter is installed on same side as the conden
sate trap, filter rack must be installed beyond
condensate trap or trap must be re-located to
avoid interference.
Trap
(same on
right side)
Plug
(same on left side)
1-1/2 in.
IMPORTANT
When combining the furnace and evaporator
coil drains together, the A/C condensate drain
outlet must be vented to relieve pressure in or
der for the furnace pressure switch to operate
properly.
5 - Figures 39 and 41 show the furnace and evaporator
coil using a separate drain. If necessary the conden
sate line from the furnace and evaporator coil can
drain together. See figures, 38, 40 and 42.
Upflow furnace (figure 40)
- In upflow furnace applica
tions 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 flood
ed heat exchanger if the combined primary drain line
were to become restricted.
Horizontal furnace (figure 42)
- In horizontal furnace
applications the field provided vent must be a mini
mum 4” to a maximum 5” length above the condensate
drain outlet connection. Any length above 5” may re
sult in a flooded heat exchanger if the combined pri
mary drain line were to become restricted.
NOTE -
In horizontal applications it is recommended to
install a secondary drain pan underneath the unit and
trap assembly.
NOTE
- Appropriately sized tubing and barbed fitting
may be used for condensate drain. Attach to the drain
on the trap using a hose clamp. See figure 36.
FIGURE 36
Tubing
Hose Clamp
Barbed Fitting
Field Provided Drain Components
Elbow
CAUTION
Do
not use copper tubing or existing copper conden
sate lines for drain line.
6 - If unit will be started immediately upon completion of in
stallation, prime trap per procedure outlined in Unit Start-
Up section.
Condensate line must slope downward away from the
trap to drain. If drain level is above condensate trap,
condensate pump must be used. Condensate drain
line should be routed within the conditioned space to
avoid freezing of condensate and blockage of drain
line. If this is not possible, a heat cable kit may be used
