035-17468-001 Rev. A (801)
22
Unitary Products Group
HORIZONTAL VENT APPLICATIONS
If installing a horizontal venting system, it is recommended
that a vent drain be added to the vent pipe to prevent the
accumulation of excess condensate in the inducer motor dur-
ing operational cycles. Refer to Figure 31.
To install the vent drain, complete the following steps:
1.
Place a tee of the proper diameter for the vent system
being installed (2" or 3") in the horizontal run closest to
the furnace.
2.
Place a reducer bushing of proper diameter in the stem
portion of the tee. The recommended size for the
reducer is 5/8”.
3.
Place a piece of 5/8” diameter or other selected size pipe
a minimum of 3" long into the reducer to serve as a
nipple.
NOTE:
Tee, reducer and nipple must be properly cemented
together using the appropriate method and materials speci-
fied in the Combustion Air Intake/Vent Connections section of
these instructions.
4.
Connect a piece of flexible drain tubing such as EPDM
rubber, Vinyl or PVC to the nipple.
5.
Loop the drain tubing to provide a trap.
6.
Connect the discharge end of the drain tube to the con-
densate disposal system externally to the furnace.
CONDENSATE PIPING
The condensate drain connection is packed in the furnace for
field installation. It consists of a formed hose with a 1/2” NPT
male connection. A 1/2” FM x 3/4” PVC slip coupling is
provided.
This drain hose may be installed to allow left or right side con-
densate drain connection. Refer to Figure 33. Cut the hose
to allow for proper fit for left or right exit.
.
To install the drain hose assembly, remove the 7/8” knockout
in the side panel. Remove the conduit nut from the 1/2” male
fitting. Push the male fitting through the hole and reinstall the
nut. The use of the 3/4” PVC coupling is optional.
FIGURE 31 :
Horizontal Vent Drain - Upflow Models
FIGURE 32 :
Horizontal Vent Drain -
Downflow/Horizontal Models
3.00” MINIMUM
LOOP DIA.
ATTACH THIS END
TO CONDENSATE
DRAIN SYSTEM
3.00 MINIMUM
LOOP DIA.
ATTACH THIS END
TO CONDENSATE
DRAIN SYSTEM
FIGURE 33 :
Condensate Piping - Upflow Models
LH DRAIN
RH DRAIN