International comfort products C Series Installation Instructions Manual page 31

INSTALLATION INSTRUCTIONS
WARNING
!
FIRE OR EXPLOSION HAZARD
A failure to follow this warning could result in personal in-
jury, death, and/or property damage.
If local codes allow the use of a flexible gas appliance
connector, always use a new listed connector. Do not use
a connector which has previously served another gas ap-
pliance. Black iron pipe shall be installed at the furnace
gas control valve and extend a minimum of 2--in. (51 mm)
outside the furnace.
CAUTION
!
FURNACE DAMAGE HAZARD
Failure to follow this caution may result in furnace dam-
age.
Connect gas pipe to furnace using a backup wrench to
avoid damaging gas controls and burner misalignment.
Table 10 Maximum Capacity of Pipe
NOMINAL
INTERNAL
IRON PIPE
DIA.
10
SIZE
IN. (MM)
(3.0)
IN. (MM)
1/2 (13)
0.622 (158) 175
3/4 (19)
0.824 (20.9) 360
1 ( 25)
1.049 (26.6) 680
1-1/4 (32)
1.380 (35.0) 1400
1-1/2 (39)
1.610 (40.9) 2100
* Cubic ft of gas per hr for gas pressures of 0.5 psig (14--- in. w.c.) or less and
a pressure drop of 0.5--- in. w.c. (based on a 0.60 specific gravity gas). Ref: Table 10
above, and 6.2 of current edition of the NFPA54/ANSI Z223.1.
An accessible manual equipment shutoff valve MUST be
installed external to furnace casing and within 6 ft. (1.8 M) of
furnace.
Install a sediment trap externally in riser leading to furnace as
shown in Figure 35. Connect a capped nipple into lower end of
tee. Capped nipple should extend below level of furnace gas
controls. Place a ground joint union between furnace gas
control valve and exterior manual equipment gas shutoff valve.
Figure 35 Typical Gas Pipe Arrangement
440 01 4104 07
LENGTH OF PIPE - - FT (M)
20 30 40 50
(6.0) (9.1) (12.1) (15.2)
120 97 82 73
250 200 170 151
465 375 320 285
950 770 660 580
1460 1180 990 900
L10F030
Specifications subject to change without notice.
A 1/8--in. (3 mm) NPT plugged tapping, accessible for test
gauge connection, MUST be installed immediately upstream of
gas supply connection to furnace and downstream of manual
equipment shutoff valve.
Piping should be pressure and leak tested in accordance with
the current edition of the NFGC in the United States, local, and
national plumbing and gas codes before the furnace has been
connected. Refer to current edition of NSCNGPIC in Canada.
After all connections have been made, purge lines and check
for leakage at furnace prior to operating furnace.
NOTE: The furnace gas control valve inlet pressure tap
connection is suitable to use as test gauge connection
providing test pressure DOES NOT exceed maximum 0.5 psig
(14--in. w.c.) stated on gas control valve. (See Figure 36)
Figure 36 Gas Valve (Single Stage)
ON/OFF Switch
1/2" NPT Inlet
1/8" NPT Inlet
Pressure Tap
Representative drawing only, some models may vary.
If pressure exceeds 0.5 psig (14--in. w.c.), 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. w.c.), 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.
Gas entry can be from left or right side, or top panel. (See
Figure 37 and Figure 38)
Gas Pipe Grommet
For direct vent (2-pipe) applications, the knockout for the gas
pipe must be sealed to prevent air leakage. Remove the
knockout, install the grommet in the knockout, then insert the
gas pipe. The grommet is included in the loose parts bag. (See
Figure 37)
Gas Furnace: N9MSB
Regulator Seal Cap
Regulator Adjustment
Regulator Seal Cap under Cap
1/2" NPT Outlet
1/8" NPT Manifold
Pressure Tap
A11153
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