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Piping should be pressure and leak tested in accordance with
NFGC in the United States or NSCNGPIC in Canada, local, and
national plumbing and gas codes before the furnace has been
connected. After all connections have been made, purge lines and
check for leakage at furnace prior to operating furnace.
If pressure exceeds 0.5 psig (14-in. wc), gas supply pipe must be
disconnected from furnace and capped before and during supply
pipe pressure test. If test pressure is equal to or less than 0.5 psig
(14-in. wc), turn off electric shutoff switch located on furnace gas
control valve and accessible manual equipment shutoff valve
before and during supply pipe pressure test. After all connections
have been made, purge lines and check for leakage at furnace prior
to operating furnace.
The gas supply pressure shall be within the maximum and
minimum inlet supply pressures marked on the rating plate with
the furnace burners ON and OFF.
ELECTRICAL CONNECTIONS
ELECTRICAL SHOCK HAZARD
Failure to follow this warning could result in personal injury
or death.
Blower access panel door switch opens 115-v power to
control. No component operation can occur. Do not bypass or
close switch with panel removed.
See Fig. 25 for field wiring diagram showing typical field 115-v
wiring. Check all factory and field electrical connections for
tightness.
Field-supplied wiring shall conform with the limitations of 63°F
(33°C) rise.
ELECTRICAL SHOCK AND FIRE HAZARD
Failure to follow this warning could result in personal injury,
death, or property damage.
The cabinet MUST have an uninterrupted or unbroken ground
according to NEC ANSI/NFPA 70-2002 and Canadian Elec-
trical Code CSA C22.1 or local codes to minimize personal
injury if an electrical fault should occur. This may consist of
electrical wire, conduit approved for electrical ground or a
listed, grounded power cord (where permitted by local code)
when installed in accordance with existing electrical codes.
Refer to the power cord manufacturer’s ratings for proper
wire gauge. Do not use gas piping as an electrical ground.
FURNACE MAY NOT OPERATE
Failure to follow this caution may result in intermitent
furnace operation.
Furnace control must be grounded for proper operation or else
control will lock out. Control must remain grounded through
green/yellow wire routed to gas valve and manifold bracket
screw.
115-V WIRING
Verify that the voltage, frequency, and phase correspond to that
specified on unit rating plate. Also, check to be sure that service
provided by utility is sufficient to handle load imposed by this
equipment. Refer to rating plate or Table 7 for equipment electrical
specifications.
U.S. installations:
Make all electrical connections in accordance
with National Electrical Code (NEC) ANSI/NFPA 70-2002 and
any local codes or ordinances that might apply.
Canadian installations:
Make all electrical connections in accor-
dance with Canadian Electrical Code CSA C22.1 or authorities
having jurisdiction.
FIRE HAZARD
Failure to follow this warning could result in personal injury,
death, or property damage.
Do not connect aluminum wire between disconnect switch
and furnace. Use only copper wire.
Use a separate, fused branch electrical circuit with a properly sized
fuse or circuit breaker for this furnace. See Table 7 for wire size
Table 6—Maximum Capacity of Pipe*
NOMINAL
IRON
PIPE
SIZE
(IN.)
INTERNAL
DIAMETER
(IN.)
LENGTH OF PIPE (FT)
10
20
30
40
50
1/2
0.622
175
120
97
82
73
3/4
0.824
360
250
200
170
151
1
1.049
680
465
375
320
285
1-1/4
1.380
1400
950
770
660
580
1-1/2
1.610
2100
1460
1180
990
900
* Cubic ft of natural gas per hr for gas pressures of 0.5 psig (14–in. wc) or less
and a pressure drop of 0.5–in wc (based on a 0.60 specific gravity gas).
Ref: Table 12.2 ANSI Z223-2002/NFPA 54-2002.
Fig. 21a—Burner and Manifold
A05028
Fig. 21b—Typical Gas Pipe Arrangement
A02035
UNION
SEDIMENT
TRAP
MANUAL
SHUTOFF
VALVE
(REQUIRED
GAS
SUPPLY
19