34
18-CD30D1-20-EN
Installer’s Guide
This tube on downflow units will need to be cut to fit be
-
tween the Inducer and the trap. On upflow units, this tube
may need to be extended, using the tubing shipped with
the furnace.
Connections must be made to an
OPEN / VENTED
DRAIN
. Outdoor draining of the furnace and coil conden-
sate is permissible if allowed by local codes.
s
s
CAUTION
!
Caution should be taken to prevent drains from freezing or causing
slippery conditions that could lead to personal injury. Excessive
draining of condensate may cause saturated ground conditions
that may result in damage to plants.
NOTE:
Use 1/2" or larger PVC or CPVC pipe and fittings as re-
quired for drain connections (fittings, pipe and solvent
cement not provided).
NOTE:
A corrosion resistant condensate pump must be used
if a pump is required for a specific drain system.
IMPORTANT:
The condensate drain should be installed with provisions
to prevent winter freeze-up of the condensate drain line.
Frozen condensate will block drains, resulting in furnace
shutdown. If the drain line cannot be installed in a condi-
tioned space, then UL listed heat tape should be applied
as required to prevent freezing (per manufacturer’s instruc-
tions). The heat tape should be rated at 5 or 6 watts per
foot at 120 volts. Self-regulating (preferred) or thermostati-
cally controlled heat tape is required.
NOTE:
All supplied flexible condensate piping is for internal
use only. All condensate piping external to the unit
must be CPVC or PVC piping.
GAS PIPING
s
s
WARNING
!
FIRE - EXPLOSION HAZARD
DO NOT RUN FLEXIBLE GAS LINE THROUGH THE FURNACE
CABINET WALL OR WITHIN THE FURNACE CABINET. FAILURE TO
FOLLOW THIS WARNING COULD RESULT IN PROPERTY DAMAGE,
SERIOUS PERSONAL INJURY, OR DEATH.
s
s
CAUTION
!
Use a backup wrench on the Gas Valve when installing Gas Piping
to prevent damage to the Gas Valve and Manifold Assembly.
The upflow/ horizontal furnace is shipped standard for left
side installation of Gas Piping. A cutout is provided on the
right side for an alternate Gas Piping arrangement.
The installation of piping shall be in accordance with
piping codes and the regulations of the local gas
company. Pipe joint compound must be resistant to
the chemical reaction with liquefied petroleum gases.
Flexible gas connections, if applied, must not be routed
through the cabinet of the furnace.
Refer to Natural Gas Piping Table 13 for delivery sizes.
NOTE: Refer to local codes and the National Fuel Gas Code,
current edition, for gas pipe requirements.
The furnace and its individual shut-off valve must be
disconnected from the Gas Supply Piping system during
any pressure testing of that system at test pressures in
excess of 1/2 psig (3.5 kPa).
The furnace must be isolated from the Gas Supply Piping
by closing its individual manual shut-off valve during any
pressure testing of the Gas Supply Piping system at test
pressures equal to or less than 1/2 psig (3.5 kPa).
NOTE:
Maximum pressure to the Gas Valve for natural gas is
13.8" W.C. Minimum pressure is 5.0" W.C. Maximum
pressure to the Gas Valve for Propane is 13.8" W.C.
Minimum pressure is 11.0" W.C.
TABLE 13
NATURAL GAS ONLY
TABLE OF CUBIC FEET PER HOUR OF GAS
FOR VARIOUS PIPE SIZES AND LENGTHS
PIPE
SIZE
LENGTH OF PIPE
10
20
30
40
50
60
70
1/2
132
92
73
63
56
50
46
3/4
278
190
152
130
115
105
96
1
520
350
285
245
215
195
180
1-1/4
1050
730
590
520
440
400
370
This table is based on Pressure Drop of 0.3 inch W.C. and 0.6 SP.GR. Gas
All Gas fittings must be checked for leaks using a soapy
solution before lighting the furnace.
DO NOT CHECK
WITH AN OPEN FLAME!
COMBUSTION AND INPUT CHECK
(SEE ALSO HIGH ALTITUDE DERATE)
NOTE: Before checking or adjusting the gas pressure,
make sure the condensate trap has been primed.
1.
Make sure all Gas appliances are off except the fur-
Cut off curved end of
Inducer drain hose
DOWNFLOW (HORIZONTAL)
(
