15
NOTE: Pressure test the gas supply system after the gas supply
piping is connected to the gas valve. The supply piping must be
disconnected from the gas valve during the testing of the piping
systems when test pressure is in excess of 0.5 psig (3450 Pa). Pres-
sure test the gas supply piping system at pressures equal to or less
than 0.5 psig (3450 Pa). The unit heating section must be isolated
from the gas piping system by closing the external main manual
shutoff valve and slightly opening the ground-joint union.
Check for gas leaks at the field-installed and factory-installed
gas lines after all piping connections have been completed. Use
soap-and-water solution (or method specified by local codes
and/or regulations).
NOTE: If orifice hole appears damaged or it is suspected to have
been redrilled, check orifice hole with a numbered drill bit of cor-
rect size. Never redrill an orifice. A burr-free and squarely aligned
orifice hole is essential for proper flame characteristics. See
Fig. 22.
Fig. 22 — Orifice Hole
Step 12 — Install External Condensate Trap and
Line
The unit has one
3
/
4
-in. condensate drain connection on the end
of the condensate pan and an alternate connection on the bot-
tom. See Fig. 23. Unit airflow configuration does not deter-
mine which drain connection to use. Either drain connection
can be used with vertical or horizontal applications.
When using the standard side drain connection, ensure the red
plug in the alternate bottom connection is tight. Do this before
setting the unit in place. The red drain pan can be tightened
with a
1
/
2
-in. square socket drive extension.
To use the alternate bottom drain connection, remove the red
drain plug from the bottom connection (use a
1
/
2
-in. square sock-
et drive extension) and install it in the side drain connection.
The piping for the condensate drain and external trap can be
completed after the unit is in place. See Fig. 24.
Fig. 23 — Condensate Drain Pan (Side View)
Fig. 24 — Condensate Drain Pan Piping Details
All units must have an external trap for condensate drainage.
Install a trap at least 4-in. (102 mm) deep and protect against
freeze-up. If drain line is installed downstream from the exter-
nal trap, pitch the line away from the unit at 1-in. per 10 ft
(25 mm per 3 m) of run. Do not use a pipe size smaller than the
unit connection (
3
/
4
-in.).
Step 13 — Make Electrical Connections
NOTE: Field-supplied wiring shall conform with the limitations
of minimum 63°F (33°C) rise.
FIELD POWER SUPPLY
If equipped with optional Powered Convenience Outlet, the
power source leads to the convenience outlet’s transformer pri-
mary are not factory connected. Installer must connect these
leads according to required operation of the convenience outlet.
If an always-energized convenience outlet operation is desired,
connect the source leads to the line side of the unit-mounted dis-
connect. (Check with local codes to ensure this method is ac-
ceptable in your area.) If a de-energize via unit disconnect switch
WARNING
Failure to follow this warning could result in personal inju-
ry, death and/or property damage.
• Connect gas pipe to unit using a backup wrench to
avoid damaging gas controls.
• Never purge a gas line into a combustion chamber.
• Never test for gas leaks with an open flame. Use a
commercially available soap solution made specifically
for the detection of leaks to check all connections.
• Use proper length of pipe to avoid stress on gas control
manifold.
BURNER
ORIFICE
WARNING
Failure to follow this warning could result in personal inju-
ry or death.
Do not use gas piping as an electrical ground.
Unit cabinet must have an uninterrupted, unbroken electri-
cal ground to minimize the possibility of personal injury if
an electrical fault should occur. This ground may consist of
electrical wire connected to unit ground lug in control com-
partment, or conduit approved for electrical ground when
installed in accordance with NEC (National Electrical
Code); ANSI/NFPA 70, latest edition (in Canada, Canadian
Electrical Code CSA [Canadian Standards Association]
C22.1), and local electrical codes.
DRAIN
(FACTORY-INSTALLED)
PLUG
CONDENSATE PAN (SIDE VIEW)
STANDARD
SIDE DRAIN
ALTERNATE
BOTTOM DRAIN
NOTE: Tr
a
p
s
ho
u
ld
b
e deep eno
u
gh to off
s
et m
a
xim
u
m
u
nit
s
t
a
tic
difference. A 4-in. (102 mm) tr
a
p i
s
recommended.
MINIMUM PITCH
1˝ (25 mm) PER
1
0´
(
3
m) OF LINE
BA
S
E RAIL
OPEN
VENT
TO ROOF
DRAIN
DRAIN PLUG
ROOF
CURB
S
EE NOTE
3
˝ (76 mm)
MIN
