70
Gas Supply
IMPORTANT: Any additions, changes or conversions re-
quired for the furnace to satisfactorily meet the application
should be made by a qualified installer, service agency or
the gas supplier, using factory-specified or approved parts.
IMPORTANT: Connect this furnace only to gas supplied by
a commercial utility or commercial fuel provider.
IMPORTANT: U.L. or CSA recognized fuel gas and carbon
monoxide (CO) detector(s) are recommended in all appli-
cations, and their installation should be in accordance with
the manufacturer’s recommendations and/or local laws,
rules, regulations or customs.
Install the gas piping according to all local codes and regu-
lations of the utility company.
If possible, run a separate gas supply line directly from the
meter to the furnace. Consult the local gas company for
the location of the manual main shut-off valve. The gas
line and manual gas stop must be adequate in size to
prevent undue pressure drop and never smaller than
the pipe size to the gas valve on the furnace. Refer to
Table 12 for natural gas (Table 13 for LP gas) for the rec-
ommended gas pipe size. See Figure 36 for typical gas
pipe connections.
Install a ground joint union within 3 feet of the cabinet
to easily remove the gas valve assembly. Local codes
may dictate the location of the ground joint union. In-
stall a manual shut-off valve in the gas line outside of
the furnace casing and upstream of the ground joint
union. The manual shut-off valve should be readily acces-
sible to turn the gas supply on or off. Install a drip leg in
the gas supply line as close to the furnace as possible. Al-
ways use a pipe compound resistant to the action of lique-
fied petroleum gases on all threaded connections.
IMPORTANT: When making gas pipe connections, use a
back-up wrench to prevent any twisting of the main gas
valve and manifold. Do not overtighten gas valve on pipe.
Any strains on the gas valve can change the position of
the gas orifices in the burners. This can cause erratic fur-
nace operation.
GAS
S
UP
P
L
Y
GA
S
P
I
P
I
N
G
ST-A1205-02-X0 ST-A1205-02-X0
MANUAL SHUT-OF VALVEMANUAL SHUT-OF VALVE
UNION
D
RIP LEG
UNION
DRIP LEG
ST-A1205-02-X0 ST-A1205-02-X0
MANUAL SHUT-OF VALVEMANUAL SHUT-OF VALVE
UNION
DRIP LEG
UNION
DRIP LEG
ST-A1205-02-X0
FIGURE 36
G
AS PIPING INSTALLATION
!
W
A
RNI
NG
THIS FURNACE IS EQUIPPED AT THE FACTORY
FOR USE ON NATURAL GAS ONLY. CONVERSION
TO LP GAS REQUIRES A SPECIAL KIT IS AVAIL-
ABLE AT THE DISTRIBUTOR. FAILURE TO USE THE
PROPER CONVERSION KIT CAN CAUSE FIRE,
CARBON MONOXIDE POISONING, EXPLOSION,
PROPERTY DAMAGE, PERSONAL INJURY OR
DEATH. SEE THE CONVERSION KIT INDEX SUP-
PLIED WITH THE FURNACE. THIS INDEX IDENTI-
FIES THE PROPER LP GAS CONVERSION KIT
REQUIRED FOR EACH PARTICULAR FURNACE.
CONVENTIONAL
ALTERNATE
UPFLOW
(CONTINUED ON NEXT PAGE)
4-5 FEET ABOVE
FLOOR REQUIRED
BY SOME UTILITIES
4-5 FEET ABOVE
FLOOR REQUIRED
BY SOME UTILITIES
To Next Page
Need help?
General